Socio-economic gradients in health behaviours and overweight among children in distinct economic settings/Les gradients socioeconomiques des habitudes de sante et du surpoids chez des enfants de milieux economiques distincts.

Simen-Kapeu, Aline ; Veugelers, Paul J.

Childhood overweight has become an important public health concern. In Canada, the prevalence of overweight in childhood increased dramatically from 15% in 1977/78 to 26% in 2004. (1) Within Canada, provincial prevalence rates follow a gradient whereby western provinces have the lowest and eastern provinces the highest rates. (1) In 2004, the childhood overweight prevalence was estimated to be 21.5% in Alberta and 30% in Nova Scotia. (1) This gradient parallels the economic gradient according to which western provinces fare better than eastern provinces.

According to social ecological theory, the environment plays an important role in shaping behaviours by supporting or hindering behaviours that occur in settings such as the family, school, community or legislative/policy environments. (2) The family is a prominent element of the social environment where dietary and lifestyle behaviours are enacted and learned. (2,3) Various studies have shown associations of familial socio-economic factors with childhood overweight and its key determinants, healthy eating and physical activity. Relative to socio-economically advantaged families, children from socio-economically disadvantaged families were more likely to be overweight. (4-8) Also, studies have shown that children growing up in deprived neighbourhoods are more likely to be overweight, to have a poor diet and to be physically inactive. (9,10)

The above is consistent with the established socio-economic gradient in health whereby wealth and health coincide. For adults, however, we recently reported that the socio-economic gradient no longer applies to overweight. (11) Specifically, affluent men were reportedly more likely to be overweight, whereas affluence was not associated with overweight among women; higher education was inversely related to overweight among women but not among men. If the socio-economic gradient is fading among adults this may affect the family environment by means of reducing parental support and encouragement for their children to make healthy food choices and to be physically active.

In the present study we sought to determine the socio-economic gradient in overweight and underlying health behaviours among Canadian children in distinct economic settings. We further examined whether the level of parental support and encouragement for healthy eating and physical activity follows a socio-economic gradient.

METHODS

Surveys

The Raising Healthy Eating and Active Living Kids in Alberta (REAL Kids Alberta) survey aims to evaluate a comprehensive initiative by Alberta Health and Wellness to promote healthy body weights among children and youth. A survey conducted in 2008 employed a one-stage stratified random sampling design. Of the 184 randomly selected schools, 148 (80.4%) schools and 3,421 grade five students participated. Observations were weighted such that they represent provincial estimates. (12)

In 2005, the Annapolis Valley Regional School Board in Nova Scotia moved to implement comprehensive school health in all its schools. The present study includes data from all 22 elementary schools that started implementing comprehensive school health in 2005. The study includes observations of 3,009 grade five students in the school years from 2005/2006 to 2008/2009.

In both provinces, grade five students received an envelope with parent/guardian consent information and a survey to take home. The percentage of grade five students that participated following active consent was 61.2% in Alberta. In Nova Scotia, where we had applied a passive consent procedure, participation rates varied by school year between 84.5% and 86.8%.

Body Weight

In both surveys, staff measured standing height to the nearest 0.1 cm after students had removed their shoes, and body weight to the nearest 0.1 kg on calibrated digital scales. Body mass index (BMI) was calculated by dividing weight (in kilograms) by height (in metres) squared. We applied the age- and sex-specific cut-offs developed by the International Obesity Task Force to categorize the measures as normal, overweight or obese. (13)

Physical Activity

In both surveys, we determined physical activity levels of students on the basis of parent/guardian responses to the following questions: What is the 1) frequency of sports or physical activity without a coach and 2) frequency of sports or physical activity with a coach. These two items were summed, and participants engaged in sports or physical activities more than three times a week were classified as being "physically active". (12)

Nutrition

According to students' responses to the Harvard Food Frequency Questionnaire (14) administered in both surveys, we categorized students as meeting the recommendations if their diet included six or more daily servings of vegetables and fruits. (12)

Socio-economic Factors

The questionnaire completed by the parents/guardians provided information on their educational attainment (secondary school or less, community college and graduate university) and household income. As income levels in the two provinces are different, household income was categorized differently: in Alberta household income categories were [less than or equal to] $50,000; $50,001-$75,000; $75,001-$100,000 and [greater than or equal to] $100,001. In the Annapolis Valley survey these were [less than or equal to] $40,000; $40,001-$60,000; $60,001-$80,000 and [greater than or equal to] $80,001.

Parental Support and Encouragement

This information was only available for participants in Alberta. Parents/guardians were asked about 1) personally caring about eating healthy food; 2) encouraging their child in healthy eating; and 3) eating supper in front of TV (as a measure of poor nutritional practice at home). They were also asked about 4) personally caring about staying fit and exercising; 5) encouraging their child to be physically active; and 6) engaging in physical activities together with their grade five child (as a measure of positive practice at home). More details on the surveys are reported elsewhere, (8,12) and the questionnaires used are available at REALKidsAlberta.ca.

Analytic approach

Given the sex-specific socio-economic patterns among adults, (11) we performed sex-stratified analyses. We applied multivariate multi-level logistic regression to assess the associations of socio-economic factors with overweight, nutrition, physical activity, and parental support and encouragement. Multi-level methods accommodate clustering of student observations within their school communities. (8) Analyses pertaining to dietary outcomes were further adjusted for calorie intake, as is recommended for food frequency data. Our regression analyses without stratification were adjusted for the confounding influence of sex. Missing values for income were treated as a separate covariate category. Stata Version 10 (Stata Corp, TX, USA) was used.

RESULTS

In Alberta in 2008, the prevalence of overweight was 28.5% among grade five students, and 6.7% were obese (Table 1). Of Alberta students, 26.7% met the nutrition guidelines and consumed six or more servings of vegetables and fruits per day, and 83.8% reportedly engaged three times or more per week in physical activity. In the 22 Annapolis Valley schools, the prevalence of overweight was 36.1%, and 13.0% of the students were obese. Here, 31.1% met the vegetables and fruit guidelines, and 85.3% engaged three times or more per week in physical activity (Table 1).

The socio-economic gradient of health behaviours and overweight of grade five students is displayed in Table 2. Overweight prevalence decreased with increase in household income, both in Alberta and Nova Scotia. For boys in Nova Scotia, though, the differences by income did not reach statistical significance. The educational attainment of parents was not significantly associated with children's body weights. A pronounced socio-economic gradient for both parental education and income in relation to physical activity was observed in both Alberta and Nova Scotia (Table 2). With respect to nutrition, we did not observe consistent socio-economic gradients. We did observe lower consumption of vegetables and fruits among Albertan girls of parents who reported college education and among Nova Scotian boys of lower income families (Table 2).

Table 3 shows the socio-economic gradient with respect to parental support and encouragement for healthy eating and physical activity. Relative to those with socio-economic disadvantaged backgrounds, parents with better education and higher income did care more about healthy eating, staying fit and exercising, and they encouraged their children more in healthy eating and physical activity. Socio-economically advantaged parents also reported practising healthier eating habits by engaging less in eating supper in front of the TV. In contrast, they engaged less in physical activities with their children as a means to role model active living at home (Table 3).

DISCUSSION

The present study shows for two economically distinct settings a socio-economic gradient whereby children of families with less income were more likely to be overweight. No overweight differentials were observed with respect to parental education. Further, no socio-economic gradient was observed with respect to the number of vegetables and fruits consumed, whereas both increasing levels of household income and parental education were associated with higher activity levels among grade five children.

Our finding regarding the negative association of income and body weight is congruent with studies among children and adolescents in North America (1,8,9,15) and around the world. (5-7) This, presumably, results from income differentials with respect to nutrition and physical activity. Whereas the present study did show a strong positive association of socio-economic status with physical activity, it did not show an association between socio-economic status and consumption of vegetables and fruits. Although several studies have confirmed a positive association between socio-economic status and physical activity, (16,17) others have found no association (18,19) or an inverse association. (20) Previous studies involving Canadian children and youth that have examined the influence of socioeconomic status have revealed that parental education was positively associated with vegetable and fruit consumption. (3,21) Education may provide mothers with knowledge of the role of nutrition in health, awareness of child weight as a health risk factor and an understanding of feeding practices conducive to healthy weight. (22)

Educational attainment and income are widely acknowledged as essential determinants of health. However, we had previously reported that this socio-economic gradient in health does not apply to overweight in adult Canadians, an observation also made in other countries. (11) Specifically, among adult men we found no association between educational attainment and overweight, which is consistent with what we observed for boys in the present study. Among adult women with higher educational attainment we reported lower overweight rates, whereas in the present study we observed only small differences in overweight rates among girls according to parental education. The most striking difference between both studies is that we observed a positive association between household income and body weight among men and a negative association between household income and body weight among boys. Among women we did not observe an association of income with body weight, whereas among girls this association was negative, similar to the one among boys.

Clearly, socio-economic differentials among adults are distinct from those among children. One may speculate that the weight of parents affects their educational messages or that it otherwise affects the family environment in terms of parental support and encouragement for healthy eating and physical activity by their children. However, our study has shown clear socio-economic gradients whereby parents with higher education and earnings provided more support and encouragement to their children with respect to healthy eating and physical activity. The exception was that these parents engaged less in physical activities with their children. The socio-economic differentials in parental support and encouragement may provide targets for public health interventions to promote healthy eating and active living and thus reduce socio-economic disparities in health behaviours and overweight among children.

The present study used a large sample of students with measured heights and weights. Although similar results between objective and self-reported physical activity have been reported, (23) our research could have benefited from the use of objective measures such as pedometers. We used vegetable and fruit consumption as a measure of healthy eating. Other proxies of a healthy diet might reveal somewhat different socio-economic gradients, though healthy eating indices tend to be strongly correlated. Socio-economic status is a construct measured with indicators such as income, educational attainment, occupational status or composite indices. Any gradient may be influenced by the indicator used, and none may capture the full meaning of the construct. Our results, however, are in keeping with recent international data that highlight the impact of socio-economic status on family lifestyle.

In conclusion, we observed a socio-economic gradient for overweight among children with no major differences between boys and girls. The present findings call for strengthening of preventive initiatives aimed at promoting healthy eating and active living among children. These initiatives should acknowledge the distinct needs of populations living in low socio-economic conditions in order to reduce health inequalities and effectively prevent childhood obesity.

Acknowledgements: We thank all of the grade five students, parents, schools and school boards for their participation in the REAL Kids Alberta and Annapolis Valley evaluations. We thank all the research assistants, health promotion coordinators, Jessie-Lee Langille, Caroline Whitby, Connie Lu, Stefan Kuhle and Delone Abercrombie for contributions to the collection and processing of the data.

This research was funded through a contract with Alberta Health and Wellness, an operating grant from the Canadian Population Health Initiative, and through a Canada Research Chair in Population Health and Alberta Innovates Health Solutions Scholarship to Dr. Paul J. Veugelers. All interpretations and opinions in the present study are those of the authors.

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(7.) Li M, Byth K, Eastman CJ. Childhood overweight and obesity by socioeconomic indexes for areas. Med J Aust 2007;187(3):195.

(8.) Veugelers PJ, Fitzgerald AL. Prevalence of and risk factors for childhood overweight and obesity. CMAJ 2005;173(6):607-13.

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(10.) Veugelers P, Sithole F, Zhang S, Muhajarine N. Neighborhood characteristics in relation to diet, physical activity and overweight of Canadian children. Int J Pediatr Obes 2008;3(3):152-59.

(11.) Kuhle S, Veugelers PJ. Why does the social gradient in health not apply to overweight? Health Rep 2009;19(4):6-15.

(12.) Simen-Kapeu A, Kuhle S, Veugelers PJ. Geographic differences in childhood overweight, physical activity, nutrition and neighborhood facilities: Implications for prevention. Can J Public Health 2010;101(1):128-32.

(13.) Cole TJ, Bellizi MC, Flegal KM, Dietz WH. Establishing a standard definition for child overweight and obesity worldwide: International survey. BMJ 2000;320:1240-43.

(14.) Rockett HR, Wolf AM, Colditz GA. Development and reproducibility of a food frequency questionnaire to assess diets of older children and adolescents. J Am Diet Assoc 1995;95:336-40.

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(18.) Riddoch CJ, Mattocks C, Deere K, Saunders J, Kirkby J, Tilling K, et al. Objective measurement of levels and patterns of physical activity. Arch Dis Child 2007;92(11):963-69.

(19.) Dollman J, Ridley K, Magarey A, Martin M, Hemphill E. Dietary intake, physical activity and TV viewing as mediators of the association of socioeconomic status with body composition: A cross-sectional analysis of Australian youth. Int J Obes 2007;31(1):45-52.

(20.) Merchant AT, Dehghan M, Behnke-Cook D, Anand SS. Diet, physical activity, and adiposity in children in poor and rich neighbourhoods: A cross-sectional comparison. Nutr J2007;6:1.

(21.) Veugelers PJ, Fitzgerald AL, Johnston E. Dietary intake and risk factors for poor diet quality among children in Nova Scotia. Can J Public Health 2005;96(3):212-16.

(22.) Saxton J, Carnell S, van Jaarsveld CH, Wardle J. Maternal education is associated with feeding style. J Am Diet Assoc 2009;109(5):894-98.

(23.) Troiano RP, Berrigan D, Dodd KW, Masse LC, Tilert T, McDowell M. Physical activity in the United States measured by accelerometer. Med Sci Sports Exerc 2008;40(1):181-88.

Aline Simen-Kapeu, MD, PhD, Paul J. Veugelers, PhD

Authors' Affiliation

School of Public Health, University of Alberta, Edmonton, AB

Correspondence and reprint requests: Dr. P.J. Veugelers, School of Public Health, University of Alberta, 650 University Terrace, 8303-112 St., Edmonton, AB T6G 2T4, Tel: 780-492-9095, Fax: 780-492-5521, E-mail: paul.veugelers@ualberta.ca

Conflict of Interest: None to declare.

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Le surpoids dans l'enfance est devenu un important probleme de sante publique. Au Canada, la prevalence du surpoids des enfants a bondi de 15% en 1977-1978 a 26% en 2004 (1). A l'interieur du pays, les taux de prevalence provinciaux suivent un gradient est-ouest: les provinces de l'Ouest affichent les taux les plus faibles, et les provinces de l'Est, les taux les plus eleves (1). En 2004, la prevalence du surpoids dans l'enfance etait estimee a 21,5% en Alberta et a 30% en Nouvelle-Ecosse1. Ce gradient est parallele au gradient economique, les provinces de l'Ouest etant plus prosperes que celles de l'Est.

D'apres la theorie de l'ecologie sociale, l'environnement joue un role important dans l'acquisition des comportements, car il appuie ou entrave les comportements qui se manifestent dans des lieux comme la famille, l'ecole, la communaute ou sur le plan des lois et des politiques (2). La famille occupe une place predominante dans l'environnement social, car c'est le lieu ou l'on acquiert et ou l'on manifeste les habitudes de vie et d'alimentation (2,3). Diverses etudes ont note des associations entre les facteurs socioeconomiques familiaux et le surpoids dans l'enfance et ses determinants cles: l'alimentation saine et l'activite physique. Compares aux enfants des familles socioeconomiquement aisees, les enfants des familles socioeconomiquement defavorisees etaient plus susceptibles d'etre en surpoids (4-8). De plus, des etudes ont montre que les enfants qui grandissent dans des quartiers defavorises sont plus susceptibles d'etre en surpoids, d'avoir une mauvaise alimentation et d'etre physiquement inactifs (9,10).

Ce qui precede est conforme au gradient socioeconomique etabli de la sante, selon lequel richesse et sante coincident. Pour les adultes cependant, nous avons recemment indique que le gradient socioeconomique ne s'applique plus au surpoids (11). Plus precisement, les hommes aises sont plus susceptibles d'etre en surpoids, tandis que l'aisance n'est pas associee au surpoids chez les femmes; les etudes superieures sont inversement liees au surpoids chez les femmes, mais pas chez les hommes. Si le gradient socioeconomique s'estompe chez les adultes, ceci pourrait avoir des incidences sur l'environnement familial en reduisant l'appui et l'encouragement des parents a l'alimentation saine et a l'activite physique chez leurs enfants.

Dans la presente etude, nous avons cherche a determiner le gradient socioeconomique du surpoids et les habitudes de sante sousjacentes chez des enfants canadiens de milieux economiques distincts. Nous avons aussi cherche a determiner si le niveau d'appui et d'encouragement des parents a l'alimentation saine et a l'activite physique suit un gradient socioeconomique.

METHODE

Sondages

Le sondage REAL Kids Alberta (Raising Healthy Eating and Active Living Kids in Alberta) visait a evaluer une vaste initiative du ministere albertain de la Sante et du Bien-etre pour promouvoir les poidssante chez les enfants et les jeunes. Ce sondage, mene en 2008, a employe une methode d'echantillonnage aleatoire stratifie en une etape. Sur 184 ecoles selectionnees au hasard, 148 ecoles (80,4%) et 3 421 eleves de 5e annee ont participe a ce sondage. Les observations ont ete ponderees de maniere a representer des estimations provincials (12).

En 2005, le Conseil scolaire regional de la Vallee de l'Annapolis, en Nouvelle-Ecosse, a decide de mettre en ceuvre l'Approche globale de la sante en milieu scolaire dans toutes ses ecoles. La presente etude englobe les donnees des 22 ecoles primaires qui ont amorce la mise en cuvre de cette approche en 2005. L'etude inclut les observations de 3 009 eleves de 5e annee durant les annees scolaires 2005-2006 a 2008-2009.

Dans les deux provinces, les eleves de 5e annee ont recu une enveloppe contenant un formulaire de consentement pour leurs parents ou tuteurs et un questionnaire a remplir a la maison. Le pourcentage d'eleves de 5e annee ayant participe a l'etude avec le consentement actif de leurs parents ou tuteurs etait de 61,2% en Alberta. En Nouvelle-Ecosse, ou nous avions opte pour une methode de consentement passif, les taux de participation ont varie, selon l'annee scolaire, entre 84,5% et 86,8%.

Poids

Dans les deux sondages, le personnel de l'etude a mesure la taille des eleves, debout et sans chaussures, arrondie a 0,1 cm, et leurs poids, arrondi a 0,1 kg, sur des balances numeriques calibrees. L'indice de masse corporelle (IMC) a ete calcule en divisant le poids (en kilogrammes) par la taille (en metres) au carre. Nous avons applique les limites par age et par sexe mises au point par le Groupe de travail international sur l'obesite pour classer les mesures dans trois categories: normal, en surpoids ou obese (13).

Activite physique

Dans les deux sondages, nous avons determine les niveaux d'activite physique des eleves d'apres les reponses de leur parent ou tuteur aux questions suivantes: A quelle frequence votre enfant fait-il du sport ou de l'activite physique 1) sans entraineur et 2) avec un entraineur. Nous avons additionne ces deux items, et les participants pratiquant un sport ou une activite physique plus de trois fois par semaine ont ete classes comme etant << actifs >> (12).

Nutrition

Selon les reponses des eleves au questionnaire Harvard sur la frequence de consommation des produits alimentaires (14), administre dans les deux sondages, nous avons classe les eleves comme res pectant les recommandations si leur regime comportait six portions quotidiennes ou plus de fruits et legumes (12).

Facteurs socioeconomiques

Le questionnaire rempli par les parents ou tuteurs contenait des renseignements sur leur niveau d'instruction (ecole secondaire ou moins, college communautaire et diplome universitaire) et sur le revenu du menage. Comme les niveaux de revenu dans les deux provinces sont differents, le revenu des menages a ete categorise differemment: en Alberta, les categories etaient les suivantes 50 000 $; 50 001 $-75 000 $; 75 001 $-100 000 $ et 100 001 $. Dans le questionnaire de la vallee de l'Annapolis, les categories etaient les suivantes: 40 000 $; 40 001 $-60 000 $; 60 001 $80 000 $ et 80 001 $.

Appui et encouragement parentaux

Cette information n'etait disponible que pour les participants en Alberta. Les parents ou tuteurs devaient repondre a des questions sur: 1) l'importance pour eux de manger des aliments sains; 2) le fait d'encourager leur enfant a avoir une alimentation saine; et 3) le fait de souper devant la television (une mesure des mauvaises habitudes nutritionnelles a la maison). D'autres questions portaient sur: 4) l'importance pour eux de rester en forme et de faire de l'exercice; 5) le fait d'encourager leur enfant a etre actif; et 6) la pratique de l'activite physique avec leur enfant de 5e annee (une mesure des bonnes habitudes a la maison). D'autres renseignements sur ces sondages ont ete publies ailleurs (8,12), et les questionnaires utilises sont disponibles sur le site REALKidsAlberta.ca.

Approche analytique

Etant donne la sexospecificite des tendances socioeconomiques chez les adultes11, nous avons fait des analyses stratifiees par sexe. Nous avons procede par regression logistique multivariee et multiniveau pour evaluer les associations entre les facteurs socioeconomiques et le surpoids, la nutrition, l'activite physique et l'appui et l'encouragement parentaux. Les methodes a niveaux multiples permettent de concentrer les observations des eleves dans leur district scolaire (8). Les analyses afferentes aux resultats nutritionnels ont ete ajustees pour tenir compte des apports en calories, comme on recommande de le faire pour les donnees sur la frequence de consommation des produits alimentaires. Nos analyses de regression sans stratification ont ete ajustees pour tenir compte de l'influence confusionnelle du sexe. Les reponses manquantes sur le revenu ont ete traitees comme une covariable de categorie distincte. Nous avons utilise le logiciel Stata version 10 (Stata Corp, Texas, Etats-Unis).

RESULTATS

En 2008 en Alberta, la prevalence du surpoids etait de 28,5% chez les eleves de 5e annee, et 6,7% etaient obeses (tableau 1). Parmi les eleves de l'Alberta, 26,7% respectaient les consignes de nutrition en consommant six portions ou plus de fruits et legumes par jour, et 83,8% disaient faire de l'activite physique trois fois par semaine ou plus. Dans les 22 ecoles de la vallee de l'Annapolis, la prevalence du surpoids etait de 36,1%, et 13,0% des eleves etaient obeses. Dans cette region, 31,1% respectaient les consignes de consommation de fruits et legumes, et 85,3% faisaient de l'activite physique trois fois par semaine ou plus (tableau 1).

Le gradient socioeconomique des habitudes de sante et du surpoids des eleves de 5e annee est presente au tableau 2. La prevalence du surpoids diminue avec l'augmentation du revenu des menages, tant en Alberta qu'en Nouvelle-Ecosse. Pour les garcons en Nouvelle Ecosse, cependant, les ecarts selon le revenu ne sont pas statistiquement significatifs. Le niveau d'instruction des parents ne presente pas de correlation significative avec le poids des enfants. En Alberta comme en Nouvelle-Ecosse, nous avons observe un gradient socioeconomique prononce pour les niveaux d'instruction et de revenu des parents en rapport avec l'activite physique (tableau 2). En ce qui a trait a la nutrition, nous n'avons pas observe de gradients socioeconomiques coherents. Cependant, la consommation de fruits et legumes est plus faible chez les filles albertaines de parents ayant fait des etudes collegiales et chez les garcons neo-ecossais vivant dans des familles a faible revenu (tableau 2).

Le tableau 3 montre le gradient socioeconomique de l'appui et de l'encouragement parentaux a l'egard de l'alimentation saine et de l'activite physique. Comparativement aux parents de milieux socioeconomiques defavorises, les parents ayant des niveaux d'instruction et de revenu plus eleves se soucient davantage de bien s'alimenter, de rester en forme et de faire de l'exercice, et ils encouragent davantage l'alimentation saine et l'activite physique chez leurs enfants. Les parents socioeconomiquement aises ont aussi des habitudes alimentaires plus saines, du fait de souper moins souvent devant la television. Par contre, ils font moins d'activite physique avec leurs enfants pour donner l'exemple d'une vie active a la maison (tableau 3).

DISCUSSION

La presente etude fait etat, dans deux milieux distincts sur le plan economique, d'un gradient socioeconomique selon lequel les enfants de familles ayant des revenus inferieurs sont plus susceptibles d'etre en surpoids. Aucun ecart relatif au surpoids n'a ete observe en ce qui a trait au niveau d'instruction parental. Aucun gradient socioeconomique n'a ete observe non plus en ce qui a trait au nombre de fruits et legumes consommes, mais les niveaux accrus de revenu du menage et d'instruction des parents sont tous les deux associes a des niveaux d'activite physique superieurs chez les enfants de 5e annee.

Notre constatation sur l'association negative entre le revenu et le poids concorde avec d'autres etudes sur les enfants et les adolescents menees en Amerique du Nord (1,8,9,15) et ailleurs dans le monde (5-7). Cela resulte probablement d'ecarts dans les revenus en ce qui a trait a la nutrition et a l'activite physique. La presente etude fait etat d'une solide association positive entre le statut socioeconomique et l'activite physique, mais elle n'indique aucune association entre le statut socioeconomique et la consommation de fruits et legumes. Bien que plusieurs etudes aient confirme une association positive entre le statut socioeconomique et l'activite physique (16,17), d'autres n'ont trouve aucune association (18,19) ou une association inverse (20). Des etudes anterieures menees aupres d'enfants et de jeunes canadiens et portant sur l'influence du statut socioeconomique ont montre que le niveau d'instruction parental etait lie positivement a la consommation de fruits et legumes (3,21). Il est possible que l'instruction donne aux meres des connaissances sur le role de la nutrition dans la sante, sur le poids des enfants en tant que facteur de risque pour la sante et sur les habitudes alimentaires propices au maintien d'un poids-sante (22).

Le niveau d'instruction et le revenu sont generalement reconnus comme des determinants essentiels de la sante. Toutefois, comme nous l'avons indique dans une etude anterieure, ce gradient socioeconomique de la sante ne s'applique pas au surpoids des Canadiens adultes, une observation qui a aussi ete faite dans d'autres pays11. Plus precisement, chez les hommes adultes, nous n'avons trouve aucune association entre le niveau d'instruction et le surpoids, ce qui est conforme a ce que nous observons chez garcons dans la presente etude. Chez les femmes adultes tres instruites, nous avons fait etat de taux de surpoids moins eleves, tandis que dans la presente etude, nous n'observons que de legeres differences dans les taux de surpoids des filles selon le niveau d'instruction parental. La difference la plus marquee entre nos deux etudes a trait a l'association observee entre le revenu du menage et le poids: cette association est positive chez les hommes et negative chez les garcons. Chez les femmes, nous n'avons pas observe d'association entre le revenu et le poids, tandis que chez les filles, cette association est negative, comme pour les garcons.

Il est clair que les ecarts socioeconomiques entres les adultes ne sont pas les memes qu'entre les enfants. On pourrait penser que le poids des parents influe sur leurs messages educatifs ou qu'il a d'autres effets sur l'environnement familial pour ce qui est de l'appui et de l'encouragement parentaux a l'egard de l'alimentation saine et de l'activite physique des enfants. Or, notre etude fait etat de gradients socioeconomiques evidents, selon lesquels les parents ayant des niveaux d'instruction et de revenu superieurs offrent davantage d'appui et d'encouragement a leurs enfants en ce qui a trait a l'alimentation saine et a l'activite physique. Seule exception: ces parents font moins d'activite physique avec leurs enfants. Les ecarts socioeconomiques dans l'appui et l'encouragement parentaux pourraient etre cibles dans les interventions de sante publique qui favorisent l'alimentation saine et la vie active, ce qui reduirait les disparites socioeconomiques dans les habitudes de sante et le surpoids des enfants.

La presente etude a fait appel a un vaste echantillon d'eleves dont nous avons mesure la taille et le poids. Bien que des resultats semblables entre l'activite physique objective et autodeclaree aient deja ete publies23, notre recherche aurait beneficie de l'utilisation de mesures objectives, comme des podometres. Nous avons utilise la consommation de fruits et legumes comme mesure de l'alimentation saine. D'autres variables substitutives pour l'alimentation saine pourraient reveler des gradients socioeconomiques un peu differents, bien que les indices de l'alimentation saine aient tendance a etre fortement correles. Le statut socioeconomique est un construit mesure par des indicateurs comme le revenu, le niveau d'instruction, la situation professionnelle ou des indices composites. N'importe quel gradient peut etre influence par les indicateurs utilises, et aucun ne peut saisir la pleine signification du construit. Nos resultats sont neanmoins conformes aux recentes donnees internationales qui font ressortir l'incidence du statut socioeconomique sur le mode de vie familial.

En conclusion, nous observons un gradient socioeconomique du surpoids chez les enfants, sans grande difference entre les garcons et les filles. Ces constatations appellent au renforcement des initiatives de prevention qui visent a promouvoir l'alimentation saine et la vie active chez les enfants. De telles initiatives devraient reconnaitre les besoins distincts des populations socioeconomiquement defavorisees afin de reduire les inegalites en sante et de prevenir efficacement l'obesite de l'enfance.

Remerciements: Nous remercions tous les eleves de 5e annee, leurs parents, les ecoles et les conseils scolaires qui ont participe aux evaluations de REAL Kids Alberta et de l'initiative du Conseil scolaire regional de la Vallee de l'Annapolis. Nous remercions aussi tous les adjoints a la recherche et les coordonnateurs de la promotion de la sante, Jessie-Lee Langille, Caroline Whitby, Connie Lu, Stefan Kuhle et Delone Abercrombie, pour leur apport a la collecte et au traitement des donnees.

Cette etude est financee par un contrat avec le ministere albertain de la Sante et du Bien-etre, une subvention de fonctionnement de l'Initiative sur la sante de la population canadienne, ainsi que par la chaire de recherche du Canada en sante des populations et la bourse Alberta Innovates--Health Solutions accordees a Paul J. Veugelers. Toutes les interpretations et opinions exprimees dans la presente etude sont celles des auteurs.

REFERENCES

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(2.) Tinsley BJ. How Children Learn To Be Healthy. Cambridge (Massachusetts), Cambridge University Press, 2003.

(3.) Pearson N, Biddle SJ, Gorely T. Family correlates of fruit and vegetable consumption in children and adolescents: A systematic review. Public Health Nutr 2009;12(2):267-83.

(4.) Lahelma E, Lallukka T, Laaksonen M, Martikainen P, Rahkonen O, Chandola T, et al. Social class differences in health behaviours among employees from Britain, Finland and Japan: The influence of psychosocial factors. Health Place 2010;16(1):61-70.

(5.) O'Dea JA, Dibley MJ. Obesity increase among low SES Australian schoolchildren between 2000 and 2006: Time for preventive interventions to target children from low income schools? Int J Public Health 2009;55(3):185-92.

(6.) Wardle J, Brodersen NH, Cole TJ, Jarvis MJ, Boniface DR. Development of adiposity in adolescence: Five year longitudinal study of an ethnically and socioeconomically diverse sample of young people in Britain. BMJ 2006;332(7550):1130-35.

(7.) Li M, Byth K, Eastman CJ. Childhood overweight and obesity by socioeconomic indexes for areas. Med J Aust 2007;187(3):195.

(8.) Veugelers PJ, Fitzgerald AL. Prevalence of and risk factors for childhood overweight and obesity. JAMC 2005;173(6):607-13.

(9.) Janssen I, Boyce WF, Simpson K, Pickett W. Influence of individual- and area-level measures of socioeconomic status on obesity, unhealthy eating, and physical inactivity in Canadian adolescents. Am J Clin Nutr 2006;83(1):139 45.

(10.) Veugelers P, Sithole F, Zhang S, Muhajarine N. Neighborhood characteristics in relation to diet, physical activity and overweight of Canadian children. Int J Pediatr Obes 2008;3(3):152-59.

(11.) Kuhle S, Veugelers PJ. Why does the social gradient in health not apply to overweight? Health Rep 2009;19(4):6-15.

(12.) Simen-Kapeu A, Kuhle S, Veugelers PJ. Geographic differences in childhood overweight, physical activity, nutrition and neighborhood facilities: Implications for prevention. Rev can sante publique 2010;101(1):128-32.

(13.) Cole TJ, Bellizi MC, Flegal KM, Dietz WH. Establishing a standard definition for child overweight and obesity worldwide: International survey. BMJ 2000;320:1240-43.

(14.) Rockett HR, Wolf AM, Colditz GA. Development and reproducibility of a food frequency questionnaire to assess diets of older children and adolescents. J Am Diet Assoc 1995;95:336-40.

(15.) Zeller MH, Modi AC. Predictors of health-related quality of life in obese youth. Obesity (Silver Spring) 2006;14(1):122-30.

(16.) Kolle E, Steene-Johannessen J, Andersen LB, Anderssen SA. Seasonal variation in objectively assessed physical activity among children and adolescents in Norway: A cross-sectional study. Int J Behav Nutr Phys Act 2009;6:36.

(17.) Mattocks C, Deere K, Leary S, Ness A, Tilling K, Blair SN, Riddoch C. Early life determinants of physical activity in 11 to 12 year olds: Cohort study. Br J Sports Med 2008;42(9):721-24.

(18.) Riddoch CJ, Mattocks C, Deere K, Saunders J, Kirkby J, Tilling K, et al. Objective measurement of levels and patterns of physical activity. Arch Dis Child 2007;92(11):963-69.

(19.) Dollman J, Ridley K, Magarey A, Martin M, Hemphill E. Dietary intake, physical activity and TV viewing as mediators of the association of socioeconomic status with body composition: A cross-sectional analysis of Australian youth. Int J Obes 2007;31(1):45-52.

(20.) Merchant AT, Dehghan M, Behnke-Cook D, Anand SS. Diet, physical activity, and adiposity in children in poor and rich neighbourhoods: A cross-sectional comparison. Nutr J2007;6:1.

(21.) Veugelers PJ, Fitzgerald AL, Johnston E. Dietary intake and risk factors for poor diet quality among children in Nova Scotia. Rev can sante publique 2005;96(3):212-16.

(22.) Saxton J, Carnell S, van Jaarsveld CH, Wardle J. Maternal education is associated with feeding style. J Am Diet Assoc 2009;109(5):894-98.

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Aline Simen-Kapeu, M.D., Ph.D., Paul J. Veugelers, Ph.D.

Affiliation des auteurs

Ecole de sante publique de l'Universite de l'Alberta, Edmonton (Alberta)

Correspondance et demandes de reimpression: Dr. P.J. Veugelers, School of Public Health, University of Alberta, 650 University Terrace, 8303--112 St., Edmonton (Alberta) T6G 2T4, tel.: 780-492-9095, telec.: 780-492-5521, courriel: paul.veugelers@ualberta.ca

Conflit d'interets: Aucun a declarer.

Table 1. Characteristics of Grade Five Students in Alberta
and Nova Scotia

                                                  Alberta   Nova Scotia
                                                     %           %

Overweight                                         28.5        36.1
Meet guidelines for vegetable and                  26.7        31.1
  fruit consumption ([greater than                 83.8        85.3
  or equal to] 6 servings/day)
Physically active with or without a coach          26.5        27.6
  ([greater than or equal to] 3 times a week)      39.9        47.6
Parental educational attainment                    33.6        24.8
  Secondary school or less                         23.4        34.3
  College diploma                                  17.5        26.2
  University degree                                22.2        18.0
Household income *                                 36.9        21.5
  Level 1                                          51.4        50.5
  Level 2                                          87.4        n.a.
  Level 3                                          89.7
  Level 4                                          18.0
Girls                                              73.8
Parental support and encouragement                 83.7
  Care about eating healthy food                    7.8
  Encourage your child to eat healthy food
  Eat supper in front of TV
  Care about staying fit and exercising
  Encourage your child to be physically active
  Engage in physical activities with your child

Table 2. Socio-economic Gradients With Respect to Overweight,
Nutrition and Physical Activity Among Grade Five Students in
Alberta and Nova Scotia

                                             Boys *
                                             OR (95% CI)

Overweight
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            1.04 (0.74, 1.45)
  University degree                          0.77 (0.54, 1.10)
Household income ([double dagger])
  Level 1                                    1.72 (1.16, 2.54)
  Level 2                                    1.11 (0.73, 1.67)
  Level 3                                    1.15 (0.83, 1.60)
  Level 4                                    1.00
Meet guidelines of 6 or more
servings of vegetables and fruits
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            0.78 (0.56, 1.09)
  University degree                          0.98 (0.65, 1.48)
Household income
  Level 1                                    1.09 (0.77, 1.72)
  Level 2                                    0.90 (0.53, 1.54)
  Level 3                                    1.05 (0.68, 1.62)
  Level 4                                    1.00
Physical activity without or
with a coach
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            1.53 (1.00, 2.38)
  University degree                          1.66 (0.92, 2.96)
Household income
  Level 1                                    0.10 (0.05 0.19)
  Level 2                                    0.19 (0.10, 0.42)
  Level 3                                    0.28 (0.13, 0.58)
  Level 4                                    1.00

                                             Girls *
                                             OR (95% CI)

Overweight
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            1.18 (0.89, 1.57)
  University degree                          0.99 (0.69, 1.37)
Household income ([double dagger])
  Level 1                                    1.32 (0.94, 1.85)
  Level 2                                    1.68 (1.06, 2.66)
  Level 3                                    0.98 (0.76, 1.49)
  Level 4                                    1.00
Meet guidelines of 6 or more
servings of vegetables and fruits
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            0.69 (0.54, 0.89)
  University degree                          0.87 (0.67, 1.13)
Household income
  Level 1                                    1.30 (0.88, 1.92)
  Level 2                                    1.06 (0.78, 1.46)
  Level 3                                    0.92 (0.66, 1.28)
  Level 4                                    1.00
Physical activity without or
with a coach
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            1.91 (1.35, 2.70)
  University degree                          1.25 (0.82, 1.92)
Household income
  Level 1                                    0.14 (0.10, 0.26)
  Level 2                                    0.20 (0.11, 0.36)
  Level 3                                    0.47 (0.25, 0.88)
  Level 4                                    1.00

                                             All ([dagger])
                                             OR (95% CI)

Overweight
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            1.11 (0.89, 1.39)
  University degree                          0.86 (0.67, 1.10)
Household income ([double dagger])
  Level 1                                    1.51 (1.16, 1.97)
  Level 2                                    1.37 (1.00, 1.90)
  Level 3                                    1.08 (0.82, 1.41)
  Level 4                                    1.00
Meet guidelines of 6 or more
servings of vegetables and fruits
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            0.74 (0.61, 0.89)
  University degree                          0.92 (0.74, 1.14)
Household income
  Level 1                                    1.22 (0.94, 1.58)
  Level 2                                    0.99 (0.75, 1.30)
  Level 3                                    0.98 (0.74, 1.30)
  Level 4                                    1.00
Physical activity without or
with a coach
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            1.68 (1.25, 2.27)
  University degree                          1.40 (1.05, 1.87)
Household income
  Level 1                                    0.13 (0.10, 0.22)
  Level 2                                    0.21 (0.13, 0.35)
  Level 3                                    0.39 (0.24, 0.64)
  Level 4                                    1.00

                                             Boys *
                                             OR (95% CI)

Overweight
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            0.92 (0.68, 1.24)
  University degree                          0.71 (0.49, 1.03)
Household income ([double dagger])
  Level 1                                    1.23 (0.80, 1.89)
  Level 2                                    1.36 (0.89, 2.10)
  Level 3                                    1.09 (0.68, 1.75)
  Level 4                                    1.00
Meet guidelines of 6 or more
servings of vegetables and fruits
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            0.86 (0.63, 1.17)
  University degree                          0.94 (0.65, 1.36)
Household income
  Level 1                                    0.65 (0.43, 0.99)
  Level 2                                    0.69 (0.45, 1.05)
  Level 3                                    0.79 (0.50, 1.23)
  Level 4                                    1.00
Physical activity without or
with a coach
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            1.06 (0.73, 1.53)
  University degree                          2.38 (1.37, 4.11)
Household income
  Level 1                                    0.42 (0.22, 0.78)
  Level 2                                    0.82 (0.42, 1.60)
  Level 3                                    0.77 (0.37, 1.58)
  Level 4                                    1.00

                                             Girls *
                                             OR (95% CI)

Overweight
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            1.08 (0.82, 1.43)
  University degree                          0.88 (0.62, 1.25)
Household income ([double dagger])
  Level 1                                    1.85 (2.23, 2.80)
  Level 2                                    1.58 (1.02, 2.42)
  Level 3                                    1.23 (0.77, 1.97)
  Level 4                                    1.00
Meet guidelines of 6 or more
servings of vegetables and fruits
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            1.02 (0.76, 1.37)
  University degree                          1.36 (0.95, 1.94)
Household income
  Level 1                                    1.29 (0.86, 1.95)
  Level 2                                    0.98 (0.63, 1.52)
  Level 3                                    1.16 (0.73, 1.83)
  Level 4                                    1.00
Physical activity without or
with a coach
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            1.66 (1.19, 2.32)
  University degree                          3.65 (2.10, 6.34)
Household income
  Level 1                                    0.20 (0.10, 0.41)
  Level 2                                    0.36 (0.17, 0.77)
  Level 3                                    0.44 (0.19, 0.98)
  Level 4                                    1.00

                                             All ([dagger])
                                             OR (95% CI)

Overweight
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            1.00 (0.82, 1.23)
  University degree                          0.80 (0.62, 1.03)
Household income ([double dagger])
  Level 1                                    1.52 (1.13, 2.04)
  Level 2                                    1.47 (1.08, 1.99)
  Level 3                                    1.16 (0.83, 1.61)
  Level 4                                    1.00
Meet guidelines of 6 or more
servings of vegetables and fruits
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            0.94 (0.76, 1.16)
  University degree                          1.16 (0.90, 1.49)
Household income
  Level 1                                    0.92 (0.69, 1.23)
  Level 2                                    0.84 (0.62, 1.13)
  Level 3                                    0.97 (0.71, 1.34)
  Level 4                                    1.00
Physical activity without or
with a coach
Parental educational attainment
  [less than or equal to] Secondary school   1.00
  College diploma                            1.35 (1.06, 1.72)
  University degree                          2.89 (1.97, 4.23)
Household income
  Level 1                                    0.29 (0.18, 0.47)
  Level 2                                    0.55 (0.34, 0.91)
  Level 3                                    0.59 (0.35, 1.00)
  Level 4                                    1.00

* Odds ratios (OR) adjusted for parental education and household
income.

([dagger]) Odds ratios (OR) adjusted for sex, parental education
and household income.

([double dagger]) Alberta: level 1=[less than or equal to] $50,000,
level 2=$50,001-75,000, level 3=$75,001-100,000, level 4 = [greater
than or equal to]$100,001. Nova Scotia: level 1=[less than or equal
to]$40,000, level 2=$40,001-60,000, level 3=$60,001-80,000, level
4=[greater than or equal to] $80,001.

Table 3. Socio-economic Gradients With Respect to Parental Support
and Encouragement of Grade Five Students in Alberta

                                    Boys *              Girls *
                                 OR (95% CI)          OR (95% CI)

Nutrition                      Care about eating healthy food

Parental educational
attainment
  [less than or equal to]      1.00                1.00
    Secondary school
  College diploma              1.03 (0.69, 1.46)   0.91 (0.58, 1.43)
  University degree            1.85 (1.35, 2.45)   1.43 (0.84, 2.42)
Household income
  [less than or equal to]      0.35 (0.19, 0.63)   0.62 (0.38, 1.03)
    $50,000
  $50,001-75,000               0.51 (0.25, 1.00)   1.04 (0.53, 2.03)
  $75,001-100,000              0.55 (0.32, 0.94)   0.77 (0.42, 1.44)
  [greater than or equal to]   1.00                1.00
    $100,001

Physical activity              Care about staying fit and exercising

Parental educational
attainment
  [less than or equal to]      1.00                1.00
    Secondary school
  College diploma              1.73 (1.27, 2.35)   1.32 (0.96, 1.80)
  University degree            1.61 (1.16, 2.22)   1.48 (1.04, 2.10)
Household income
  [less than or equal to]      0.44 (0.28, 0.68)   0.44 (0.30, 0.65)
    $50,000
  $50,001-75,000               0.72 (0.46, 1.12)   0.67 (0.43, 1.03)
  $75,001-100,000              0.52 (0.35, 1.77)   0.78 (0.52, 1.16)
  [greater than or equal to]   1.00                1.00
    $100,001

                                 All ([dagger)          Boys *
                                  OR (95% CI)        OR (95% CI)

                                                   Encourage your
                               Care about eating   child to eat
Nutrition                      healthy food        healthy food

Parental educational
attainment
  [less than or equal to]      1.00                1.00
    Secondary school
  College diploma              1.15 (0.84, 1.57)   1.33 (0.81, 2.18)
  University degree            1.74 (1.22, 2.48)   1.97 (1.08, 3.58)
Household income
  [less than or equal to]      0.51 (0.33, 0.75)   0.50 (0.26, 0.94)
    $50,000
  $50,001-75,000               0.76 (0.48, 1.20)   1.26 (0.51, 3.06)
  $75,001-100,000              0.69 (0.46, 1.04)   0.65 (0.34, 1.25)
  [greater than or equal to]   1.00                1.00
    $100,001
                               Care about          Encourage your
                               staying fit and     child to be
Physical activity              exercising          physically active

Parental educational
attainment
  [less than or equal to]      1.00                1.00
    Secondary school
  College diploma              1.48 (1.19, 1.85)   0.91 (0.61, 1.36)
  University degree            1.53 (1.19, 1.93)   1.00 (0.60, 1.65)
Household income
  [less than or equal to]      0.43 (0.32, 0.59)   0.37 (0.21, 0.65)
    $50,000
  $50,001-75,000               0.69 (0.51, 0.95)   0.76 (0.39, 1.47)
  $75,001-100,000              0.64 (0.48, 0.86)   0.87 (0.51, 1.48)
  [greater than or equal to]   1.00                1.00
    $100,001

                                    Girls *          All ([dagger)
                                  OR (95% CI)         OR (95% CI)

                               Encourage your child to eat healthy
Nutrition                      food

Parental educational
attainment
  [less than or equal to]      1.00                1.00
    Secondary school
  College diploma              0.89 (0.51, 1.57)   1.08 (0.72, 1.61)
  University degree            1.02 (0.55, 1.90)   1.40 (0.91, 2.15)
Household income
  [less than or equal to]      0.56 (0.28, 1.11)   0.53 (0.36, 0.79)
    $50,000
  $50,001-75,000               0.63 (0.29, 1.34)   0.83 (0.49, 1.42)
  $75,001-100,000              0.63 (0.29, 1.33)   0.65 (0.39, 1.08)
  [greater than or equal to]   1.00                1.00
    $100,001

                               Encourage your child to be physically
Physical activity              active

Parental educational
attainment
  [less than or equal to]      1.00                1.00
    Secondary school
  College diploma              1.18 (0.83, 1.69)   1.07 (0.82,1.38)
  University degree            1.26 (0.91, 1.74)   1.22 (0.90,1.67)
Household income
  [less than or equal to]      0.47 (0.30, 0.73)   0.46 (0.32,0.65)
    $50,000
  $50,001-75,000               0.60 (0.36, 0.99)   0.68 (0.48,0.98)
  $75,001-100,000              0.68 (0.42, 1.10)   0.76 (0.55,1.06)
  [greater than or equal to]   1.00                1.00
    $100,001

                                    Boys *              Girls *
                                 OR (95% CI)          OR (95% CI)

Nutrition                      Eat supper in front of TV

Parental educational
attainment
  [less than or equal to]      1.00                1.00
    Secondary school
  College diploma              0.74 (0.51, 1.07)   0.76 (0.55, 1.05)
  University degree            0.60 (0.39, 0.91)   0.59 (0.42, 0.83)
Household income
  [less than or equal to]      2.26 (1.47, 3.46)   2.94 (1.89, 4.58)
    $50,000
  $50,001-75,000               1.20 (0.74, 1.96)   2.14 (1.35, 3.39)
  $75,001-100,000              1.39 (0.90, 2.13)   1.69 (1.08, 2.65)
  [greater than or equal to]   1.00                1.00
    $100,001

                               Engage in physical activities with
Physical activity              your child

Parental educational
attainment
  [less than or equal to]      1.00                1.00
    Secondary school
  College diploma              0.95 (0.61, 1.69)   0.95 (0.55, 1.63)
  University degree            0.65 (0.40, 1.07)   0.63 (0.36, 1.08)
Household income
  [less than or equal to]      1.69 (0.84, 3.37)   2.54 (1.40, 4.63)
    $50,000
  $50,001-75,000               1.11 (0.50, 2.45)   1.49 (0.67, 3.30)
  $75,001-100,000              1.29 (0.67, 2.46)   0.81 (0.42, 1.55)
  [greater than or equal to]   1.00                1.00
    $100,001

                                 All ([dagger)
                                  OR (95% CI)

Nutrition                      Eat supper in front of TV

Parental educational
attainment
  [less than or equal to]      1.00
    Secondary school
  College diploma              0.75 (0.59, 0.96)
  University degree            0.59 (0.45, 0.77)
Household income
  [less than or equal to]      2.56 (1.91, 3.42)
    $50,000
  $50,001-75,000               1.63 (1.14, 2.34)
  $75,001-100,000              1.52 (1.10, 2.09)
  [greater than or equal to]   1.00
    $100,001

                               Engage in physical activities
Physical activity              with your child

Parental educational
attainment
  [less than or equal to]      1.00
    Secondary school
  College diploma              0.96 (0.67, 1.37)
  University degree            0.65 (0.42, 0.99)
Household income
  [less than or equal to]      1.85 (1.16, 2.94)
    $50,000
  $50,001-75,000               1.23 (0.71, 2.14)
  $75,001-100,000              1.00 (0.64, 1.54)
  [greater than or equal to]   1.00
    $100,001

* Odds ratios (OR) adjusted for parental education and household
income.

([dagger]) Odds ratios (OR) adjusted for sex, parental education
and household income.

Tableau 1. Caracteristiques des eleves de 5e annee en Alberta
et en Nouvelle-Ecosse

                                           Alberta   Nouvelle-Ecosse
                                              %            %

En surpoids                                 28,5          36,1
Respectent les consignes de consommation
  de fruits et legumes ([greater than or    26,7          31,1
  equal to] 6 portions/jours)
Actifs avec ou sans entraineur
  ([greater than or equal to] 3 fois par    83,8          85,3
    semaine)
Niveau d'instruction parental
  Diplome d'etudes secondaires ou moins     26,5          27,6
  Diplome collegial                         39,9          47,6
  Diplome universitaire                     33,6          24,8
Revenu du menage *
  Niveau 1                                  23,4          34,3
  Niveau 2                                  17,5          26,2
  Niveau 3                                  22,2          18,0
  Niveau 4                                  36,9          21,5
Filles                                      51,4          50,5
Appui et encouragement parentaux                          n.d.
  Veulent manger des aliments sains         87,4
  Encouragent leur enfant a manger des
    aliments sains                          89,7
  Soupent devant la television              18,0
  Veulent rester en forme et faire de       73,8
    l'exercice
  Encouragent leur enfant a etre actif      83,7
  Font de l'activite physique avec           7,8
    leur enfant

* Alberta : niveau 1 = [less than or equal to] 50 000 $,
niveau 2=50 001 $-75 000 $, niveau 3=75 001 $-100 000 $,
niveau 4=[greater than or equal to] 100 001 $. Nouvelle-
Ecosse : niveau 1 = [less than or equal to] 40 000 $,
niveau 2=40 001 $-60 000 $, niveau 3=60 001 $-80 000 $,
niveau 4=[greater than or equal to] 80 001 $.

n.d.=donnees non disponibles

Tableau 2. Gradients socioeconomiques du surpoids, de la nutrition
et de l'activite physique chez les eleves de 5e annee en Alberta et
en Nouvelle-Ecosse

                                                Alberta

                                                Garcons *
                                                RC (IC 95 %)

En surpoids
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             1,04 (0,74-1,45)
  Diplome universitaire                         0,77 (0,54-1,10)
Revenu du menage ([double dagger])
  Niveau 1                                      1,72 (1,16-2,54)
  Niveau 2                                      1,11 (0,73-1,67)
  Niveau 3                                      1,15 (0,83-1,60)
  Niveau 4                                      1,00
Respectent les consignes de consommation
de 6 portions de fruits et legumes ou plus
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             0,78 (0,56-1,09)
  Diplome universitaire                         0,98 (0,65-1,48)
Revenu du menage
  Niveau 1                                      1,09 (0,77-1,72)
  Niveau 2                                      0,90 (0,53-1,54)
  Niveau 3                                      1,05 (0,68-1,62)
  Niveau 4                                      1,00
Actifs avec ou sans un entraineur
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             1,53 (1,00-2,38)
  Diplome universitaire                         1,66 (0,92-2,96)
Revenu du menage
  Niveau 1                                      0,10 (0,05-0,19)
  Niveau 2                                      0,19 (0,10-0,42)
  Niveau 3                                      0,28 (0,13-0,58)
  Niveau 4                                      1,00

                                                Alberta

                                                Filles *
                                                RC (IC 95 %)

En surpoids
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             1,18 (0,89-1,57)
  Diplome universitaire                         0,99 (0,69-1,37)
Revenu du menage ([double dagger])
  Niveau 1                                      1,32 (0,94-1,85)
  Niveau 2                                      1,68 (1,06-2,66)
  Niveau 3                                      0,98 (0,76-1,49)
  Niveau 4                                      1,00
Respectent les consignes de consommation
de 6 portions de fruits et legumes ou plus
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             0,69 (0,54-0,89)
  Diplome universitaire                         0,87 (0,67-1,13)
Revenu du menage
  Niveau 1                                      1,30 (0,88-1,92)
  Niveau 2                                      1,06 (0,78-1,46)
  Niveau 3                                      0,92 (0,66-1,28)
  Niveau 4                                      1,00
Actifs avec ou sans un entraineur
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             1,91 (1,35-2,70)
  Diplome universitaire                         1,25 (0,82-1,92)
Revenu du menage
  Niveau 1                                      0,14 (0,10-0,26)
  Niveau 2                                      0,20 (0,11-0,36)
  Niveau 3                                      0,47 (0,25-0,88)
  Niveau 4                                      1,00

                                                Alberta

                                                Les deuxt
                                                RC (IC 95 %)

En surpoids
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             1,11 (0,89-1,39)
  Diplome universitaire                         0,86 (0,67-1,10)
Revenu du menage ([double dagger])
  Niveau 1                                      1,51 (1,16-1,97)
  Niveau 2                                      1,37 (1,00-1,90)
  Niveau 3                                      1,08 (0,82-1,41)
  Niveau 4                                      1,00
Respectent les consignes de consommation
de 6 portions de fruits et legumes ou plus
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             0,74 (0,61-0,89)
  Diplome universitaire                         0,92 (0,74-1,14)
Revenu du menage
  Niveau 1                                      1,22 (0,94-1,58)
  Niveau 2                                      0,99 (0,75-1,30)
  Niveau 3                                      0,98 (0,74-1,30)
  Niveau 4                                      1,00
Actifs avec ou sans un entraineur
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             1,68 (1,25-2,27)
  Diplome universitaire                         1,40 (1,05-1,87)
Revenu du menage
  Niveau 1                                      0,13 (0,10-0,22)
  Niveau 2                                      0,21 (0,13-0,35)
  Niveau 3                                      0,39 (0,24-0,64)
  Niveau 4                                      1,00

                                                Nouvelle-Ecosse

                                                Garcons *
                                                RC (IC 95 %)

En surpoids
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             0,92 (0,68-1,24)
  Diplome universitaire                         0,71 (0,49-1,03)
Revenu du menage ([double dagger])
  Niveau 1                                      1,23 (0,80-1,89)
  Niveau 2                                      1,36 (0,89-2,10)
  Niveau 3                                      1,09 (0,68-1,75)
  Niveau 4                                      1,00
Respectent les consignes de consommation
de 6 portions de fruits et legumes ou plus
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             0,86 (0,63-1,17)
  Diplome universitaire                         0,94 (0,65-1,36)
Revenu du menage
  Niveau 1                                      0,65 (0,43-0,99)
  Niveau 2                                      0,69 (0,45-1,05)
  Niveau 3                                      0,79 (0,50-1,23)
  Niveau 4                                      1,00
Actifs avec ou sans un entraineur
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             1,06 (0,73-1,53)
  Diplome universitaire                         2,38 (1,37-4,11)
Revenu du menage
  Niveau 1                                      0,42 (0,22-0,78)
  Niveau 2                                      0,82 (0,42-1,60)
  Niveau 3                                      0,77 (0,37-1,58)
  Niveau 4                                      1,00

                                                Nouvelle-Ecosse

                                                Filles *
                                                RC (IC 95 %)

En surpoids
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             1,08 (0,82-1,43)
  Diplome universitaire                         0,88 (0,62-1,25)
Revenu du menage ([double dagger])
  Niveau 1                                      1,85 (2,23-2,80)
  Niveau 2                                      1,58 (1,02-2,42)
  Niveau 3                                      1,23 (0,77-1,97)
  Niveau 4                                      1,00
Respectent les consignes de consommation
de 6 portions de fruits et legumes ou plus
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             1,02 (0,76-1,37)
  Diplome universitaire                         1,36 (0,95-1,94)
Revenu du menage
  Niveau 1                                      1,29 (0,86-1,95)
  Niveau 2                                      0,98 (0,63-1,52)
  Niveau 3                                      1,16 (0,73-1,83)
  Niveau 4                                      1,00
Actifs avec ou sans un entraineur
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             1,66 (1,19-2,32)
  Diplome universitaire                         3,65 (2,10-6,34)
Revenu du menage
  Niveau 1                                      0,20 (0,10-0,41)
  Niveau 2                                      0,36 (0,17-0,77)
  Niveau 3                                      0,44 (0,19-0,98)
  Niveau 4                                      1,00

                                                Nouvelle-Ecosse

                                                Les deuxt
                                                RC (IC 95 %)

En surpoids
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             1,00 (0,82-1,23)
  Diplome universitaire                         0,80 (0,62-1,03)
Revenu du menage ([double dagger])
  Niveau 1                                      1,52 (1,13-2,04)
  Niveau 2                                      1,47 (1,08-1,99)
  Niveau 3                                      1,16 (0,83-1,61)
  Niveau 4                                      1,00
Respectent les consignes de consommation
de 6 portions de fruits et legumes ou plus
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             0,94 (0,76-1,16)
  Diplome universitaire                         1,16 (0,90-1,49)
Revenu du menage
  Niveau 1                                      0,92 (0,69-1,23)
  Niveau 2                                      0,84 (0,62-1,13)
  Niveau 3                                      0,97 (0,71-1,34)
  Niveau 4                                      1,00
Actifs avec ou sans un entraineur
Niveau d'instruction parental
  [less than or equal to] Diplome secondaire    1,00
  Diplome collegial                             1,35 (1,06-1,72)
  Diplome universitaire                         2,89 (1,97-4,23)
Revenu du menage
  Niveau 1                                      0,29 (0,18-0,47)
  Niveau 2                                      0,55 (0,34-0,91)
  Niveau 3                                      0,59 (0,35-1,00)
  Niveau 4                                      1,00

* Rapports de cotes (RC) ajustes selon le niveau d'instruction
parental et le revenu du menage.

([dagger]) Rapports de cotes (RC) ajustes selon le sexe, le
niveau d'instruction parental et le revenu du menage.

([double dagger])  Alberta : niveau 1=[less than or equal to]
50 000 $ niveau 2=50 001 $-75 000 $ niveau 3=75 001 $-100 000
$ niveau 4=[greater than or equal to] 100 001 $ Nouvelle-Ecosse
: niveau 1=[less than or equal to] 40 000 $ niveau 2=40 001
$-60 000 $, niveau 3=60 001 $-80 000 $, niveau 4=[greater than
or equal to] 80 001 $.

Tableau 3. Gradients socioeconomiques de l'appui et de l'encouragement
des parents d'eleves de 5e annee en Alberta

                               Garcons *           Filles *
                              RC (IC 95 %)       RC (IC 95 %)

Nutrition                   Veulent manger des aliments sains

Niveau d'instruction
parental
  [less than or equal to]   1,00               1,00
    Diplome secondaire
  Diplome collegial         1,03 (0,69-1,46)   0,91 (0,58-1,43)
  Diplome universitaire     1,85 (1,35-2,45)   1,43 (0,84-2,42)
Revenu du menage
  [less than or equal to]   0,35 (0,19-0,63)   0,62 (0,38-1,03)
    50 000 $
  50 001 $-75 000 $         0,51 (0,25-1,00)   1,04 (0,53-2,03)
  75 001 $-100 000 $        0,55 (0,32-0,94)   0,77 (0,42-1,44)
  [greater than or equal    1,00               1,00
    to] 100 001 $

                            Veulent rester en forme et faire
Activite physique           de l'exercice

Niveau d'instruction
parental
  [less than or equal to]   1,00               1,00
    Diplome secondaire
  Diplome collegial         1,73 (1,27-2,35)   1,32 (0,96-1,80)
  Diplome universitaire     1,61 (1,16-2,22)   1,48 (1,04-2,10)
Revenu du menage
  [less than or equal to]   0,44 (0,28-0,68)   0,44 (0,30-0,65)
    50 000 $
  50 001 $-75 000 $         0,72 (0,46-1,12)   0,67 (0,43-1,03)
  75 001 $-100 000 $        0,52 (0,35-1,77)   0,78 (0,52-1,16)
  [greater than or equal    1,00               1,00
    to] 100 001 $

                                Les deux
                               ([dagger])           Garcons *
                              RC (IC 95 %)         RC (IC 95 %)

                            Veulent manger      Encouragent leur
                            des aliments        enfant a manger
Nutrition                   sains               des aliments sains

Niveau d'instruction
parental
  [less than or equal to]   1,00                1,00
    Diplome secondaire
  Diplome collegial         1,15 (0,84-1,57)    1,33 (0,81-2,18)
  Diplome universitaire     1,74 (1,22-2,48)    1,97 (1,08-3,58)
Revenu du menage
  [less than or equal to]   0,51 (0,33-0,75)    0,50 (0,26-0,94)
    50 000 $
  50 001 $-75 000 $         0,76 (0,48-1,20)    1,26 (0,51-3,06)
  75 001 $-100 000 $        0,69 (0,46-1,04)    0,65 (0,34-1,25)
  [greater than or equal    1,00                1,00
    to] 100 001 $

                            Veulent rester en   Encouragent leur
                            forme et faire de   enfant a etre
Activite physique           l'exercice          actif

Niveau d'instruction
parental
  [less than or equal to]   1,00                1,00
    Diplome secondaire
  Diplome collegial         1,48 (1,19-1,85)    0,91 (0,61-1,36)
  Diplome universitaire     1,53 (1,19-1,93)    1,00 (0,60-1,65)
Revenu du menage
  [less than or equal to]   0,43 (0,32-0,59)    0,37 (0,21-0,65)
    50 000 $
  50 001 $-75 000 $         0,69 (0,51-0,95)    0,76 (0,39-1,47)
  75 001 $-100 000 $        0,64 (0,48-0,86)    0,87 (0,51-1,48)
  [greater than or equal    1,00                1,00
    to] 100 001 $

                                                  Les deux
                                Filles *          ([dagger])
                              RC (IC 95 %)       RC (IC 95 %)

                            Encouragent leur enfant a manger des
Nutrition                   aliments sains

Niveau d'instruction
parental
  [less than or equal to]   1,00               1,00
    Diplome secondaire
  Diplome collegial         0,89 (0,51-1,57)   1,08 (0,72-1,61)
  Diplome universitaire     1,02 (0,55-1,90)   1,40 (0,91-2,15)
Revenu du menage
  [less than or equal to]   0,56 (0,28-1,11)   0,53 (0,36-0,79)
    50 000 $
  50 001 $-75 000 $         0,63 (0,29-1,34)   0,83 (0,49-1,42)
  75 001 $-100 000 $        0,63 (0,29-1,33)   0,65 (0,39-1,08)
  [greater than or equal    1,00               1,00
    to] 100 001 $

Activite physique           Encouragent leur enfant a etre actif

Niveau d'instruction
parental
  [less than or equal to]   1,00               1,00
    Diplome secondaire
  Diplome collegial         1,18 (0,83-1,69)   1,07 (0,82-1,38)
  Diplome universitaire     1,26 (0,91-1,74)   1,22 (0,90-1,67)
Revenu du menage
  [less than or equal to]   0,47 (0,30-0,73)   0,46 (0,32-0,65)
    50 000 $
  50 001 $-75 000 $         0,60 (0,36-0,99)   0,68 (0,48-0,98)
  75 001 $-100 000 $        0,68 (0,42-1,10)   0,76 (0,55-1,06)
  [greater than or equal    1,00               1,00
    to] 100 001 $

                               Garcons *           Filles *
                              RC (IC 95 %)       RC (IC 95 %)

Nutrition                   Soupent devant la television

Niveau d'instruction
parental
  [less than or equal to]   1,00               1,00
    Diplome secondaire
  Diplome collegial         0,74 (0,51-1,07)   0,76 (0,55-1,05)
  Diplome universitaire     0,60 (0,39-0,91)   0,59 (0,42-0,83)
Revenu du menage
  [less than or equal to]   2,26 (1,47-3,46)   2,94 (1,89-4,58)
    50 000 $
  50 001 $-75 000 $         1,20 (0,74-1,96)   2,14 (1,35-3,39)
  75 001 $-100 000 $        1,39 (0,90-2,13)   1,69 (1,08-2,65)
  [greater than or equal    1,00               1,00
    to] 100 001 $

                            Font de l'activite physique avec
Activite physique           leur enfant

Niveau d'instruction
parental
  [less than or equal to]   1,00               1,00
    Diplome secondaire
  Diplome collegial         0,95 (0,61-1,69)   0,95 (0,55-1,63)
  Diplome universitaire     0,65 (0,40-1,07)   0,63 (0,36-1,08)
Revenu du menage
  [less than or equal to]   1,69 (0,84-3,37)   2,54 (1,40-4,63)
    50 000 $
  50 001 $-75 000 $         1,11 (0,50-2,45)   1,49 (0,67-3,30)
  75 001 $-100 000 $        1,29 (0,67-2,46)   0,81 (0,42-1,55)
  [greater than or equal    1,00               1,00
    to] 100 001 $

                               Les deux
                               ([dagger])
                              RC (IC 95 %)

Nutrition                   Soupent devant la television

Niveau d'instruction
parental
  [less than or equal to]   1,00
    Diplome secondaire
  Diplome collegial         0,75 (0,59-0,96)
  Diplome universitaire     0,59 (0,45-0,77)
Revenu du menage
  [less than or equal to]   2,56 (1,91-3,42)
    50 000 $
  50 001 $-75 000 $         1,63 (1,14-2,34)
  75 001 $-100 000 $        1,52 (1,10-2,09)
  [greater than or equal    1,00
    to] 100 001 $

                            Font de l'activite physique avec
Activite physique           leur enfant

Niveau d'instruction
parental
  [less than or equal to]   1,00
    Diplome secondaire
  Diplome collegial         0,96 (0,67-1,37)
  Diplome universitaire     0,65 (0,42-0,99)
Revenu du menage
  [less than or equal to]   1,85 (1,16-2,94)
    50 000 $
  50 001 $-75 000 $         1,23 (0,71-2,14)
  75 001 $-100 000 $        1,00 (0,64-1,54)
  [greater than or equal    1,00
    to] 100 001 $