Energy drink consumption and associations with demographic characteristics, drug use and injury among adolescents.
Hamilton, Hayley A. ; Boak, Angela ; Ilie, Gabriela 等
First introduced in the US and Canada in the 1990s, the popularity
of energy drinks has increased rapidly, with consumption in the US
estimated at 6 billion energy drinks in 2010 compared to 2.3 billion in
2005. (1) In addition, sales of energy drinks reached approximately $9
billion in the US in 2011, a 16% increase over the previous year. (2)
Caffeine is the primary active ingredient in energy drinks, but the
level of caffeine content varies widely across the many brands sold.
(1,3) The caffeine content per 250 mL of an energy drink is usually
80-140 mg or the equivalent of two cans of cola or a 6-oz to 8-oz cup of
coffee. (3-5) There are, however, energy drinks with caffeine content of
up to 500 mg per can. (3,4) Additional ingredients include amino acid,
vitamins, herbs, and other supplements purported to boost energy,
alertness, and mental performance. (6) The short- and long-term health
effects of many of these ingredients, and energy drink consumption in
general, are for the most part unknown. (1,7-9)
Energy drinks are often aggressively marketed to adolescents
through carefully crafted campaigns, including sponsorship of events
that appeal to this age group (e.g., snowboarding), and product
placement in video games and social media. (4,10,11) Easy access from a
convenience store, appealing names (e.g., Red Bull[R], Rockstar[R], Full
Throttle[R]), product claims of greater stamina, alertness and energy,
(12) and perceptions of energy drinks as a "legal drug", (13)
make these drinks particularly appealing to adolescents. Reports
indicate that the main consumers of energy drinks are adolescents and
young adults, (6,7) with between 30% and 50% of adolescents and young
adults consuming energy drinks. (7,11) Yet, there is relatively little
empirical data on the health and behavioural effects of energy drinks.
There is research indicating that energy drink consumption helps to
improve attention, maintain or improve performance on some difficult
activities, and decrease reaction times. (14,15) There is also evidence
of adverse consequences such as seizures, difficulty sleeping, cardiac
arrhythmia, and even death. (1,6,7) In the US, there was a twofold
increase in the number of visits to emergency departments between 2007
(10,068 visits) and 2011 (20,783 visits) that involved energy drinks,
with 12-17 year olds accounting for 11.4% and 7.2% of those visits in
2007 and 2011, respectively. (16)
In addition to questions about the health effects of energy drinks,
there are questions about the demographic, social, and behavioural
correlates of energy drink consumption among adolescents. The sparse
research that has been conducted suggests that the consumption of energy
drinks is correlated with heavy alcohol use, licit and illicit drug use,
impulsivity, and risk-taking behaviours, including fighting and risky
sexual behaviours. (7,10,17-19) Much of this research, however, has
focused on consumption among college or university students and involves
samples that are non-generalizable. (7,10,17) Despite attention from
media and regulatory agencies that highlight concerns about energy
drinks, there is a gap in the research literature with regard to
consumption among adolescents. This study will address this gap by
investigating demographic factors, academic performance, substance use,
sensation-seeking, and injury as correlates of energy drink consumption.
The study will
also examine whether these associations vary for males and females.
METHODS
Data
Data were derived from the 2011 Ontario Student Drug Use and Health
Survey (OSDUHS), a representative province-wide survey of 9,288 students
in grades 7 through 12. (20) The OSDUHS is a biennial cross-sectional
survey, ongoing since 1977, that monitors students' substance use,
gambling, mental and physical health, and delinquent behaviour. The
survey is based on a stratified two-stage cluster design (school, class)
and sampled students from 40 school boards, 181 schools, and 581
classrooms. The student participation rate was 62%. Absenteeism
accounted for 12% of the non-participation rate and parental refusal or
unreturned consent forms accounted for 26%. (20) The rate of student
participation was above average for a student survey that required
active consent from a parent or guardian. (21,22) The survey consisted
of two versions of the questionnaire, with about one half of the content
common to both. Within each classroom, one half of the students were
randomly assigned questionnaire Form A and the other half were assigned
questionnaire Form B. The blank questionnaires were presorted into A, B,
A, B, etc. prior to being distributed to students within each classroom.
Energy drink consumption was included in only one version of the
questionnaire and thus analyses to be presented are based only on this
random half sample of 4,472 students. Analyses were also restricted to
individuals ages 12 to 19. Greater detail about the study design and
methods are described elsewhere. (20) The 2011 OSDUHS received research
ethics approval from the Centre for Addiction and Mental Health and from
York University.
Measures
Dependent Variable
Energy drink consumption was determined from a question that asked
students how often they drank "a can of a high-energy caffeine
drink, such as Redbull, Rockstar, Full Throttle, Monster, etc.?"
Response categories referred to consumption in the last 7 days
(differentiating between 1 time, 2 to 4 times, 5 to 6 times, once each
day, or more than once each day); no consumption in the last 7 days, but
some consumption in the last 12 months; and no consumption in the last 7
days or in the last 12 months. A dichotomous measure was also
constructed to represent consumption (1) and non-consumption (0) of
energy drinks in the last 12 months.
Independent Variables
Several factors, in addition to sex and grade, were included as
covariates within the analyses. Cannabis use was a dichotomous measure
of use (coded 1) or non-use in the last 12 months. Tobacco use was a
dichotomous measure representing smoked (coded 1) or did not smoke
cigarettes in the last 12 months. Binge drinking was a dichotomous
measure reflecting the consumption (coded 1) or non-consumption of five
or more drinks of alcohol on the same occasion over the previous 4
weeks. (23) Non-medicinal use of prescription drugs was a dichotomous
measure defined as use (coded 1) or non-use (0) of ADHD drugs, other
stimulants, OxyContin, other opioid pain relievers, or
tranquillizers/sedatives in the last 12 months without a doctor's
prescription. These measures within the survey were adapted from another
large-scale adolescent survey. (24)
Academic performance was assessed through a question that asked
students to indicate their average marks in school. Response categories
ranged from 1 "90%-100%" to 6 "below 50%". A
dichotomous measure was constructed to represent average marks of less
than 80% (coded 1) and 80% or higher (0). Adolescent work was derived
from a question asking students to indicate the number of hours they
spent per week working for pay outside the home during the academic
year. A dichotomous measure was constructed to represent work (coded 1)
versus did not work for pay (0).
A measure of injury and treatment was based on a question that
asked students to report the number of times in the last 12 months they
were "hurt or injured, and had to be treated by a doctor or
nurse?" (25) Responses ranged from 1 (was not treated) to 5 (4 or
more times). A dichotomous measure representing treated (coded 1) versus
not treated (coded 0) for an injury was used for analysis.
Sensation-seeking was measured using the 4-item Brief Sensation
Seeking Scale. (26) Students were asked the extent to which they agree
or disagree with the following statements: "I like new and exciting
experiences, even if I have to break the rules", "I prefer
friends who are exciting and unpredictable", "I like to
explore strange places", and "I like to do frightening
things". Response categories ranged from 1 (strongly agree) to 4
(strongly disagree), but were recoded such that higher total scores
reflected higher sensation-seeking. A test of reliability indicated a
Cronbach's alpha of .79. High sensation-seeking was a dichotomous
measure defined as summed scores of 14 or higher across the four items
(coded 1), which reflects the mean of the summed scores + 1 standard
deviation.
Ethnicity was derived from a question that asked students to select
one or more response categories that best described their ethnic
background. The 12 response categories were similar to those used in the
2006 Canadian Census. (27) For purposes of analysis, individuals who
selected only one ethnic background were grouped into five categories:
White, Black, East or Southeast Asian, South Asian, and Other.
Individuals who selected multiple ethnic backgrounds (7.5% of the
sample) were coded as Other.
Data analysis
Taylor series methods within Stata 12 were utilized for analyses to
account for the complex survey sample design and obtain unbiased
variances and point estimates. (28) Analyses included population weights
to adjust for the unequal probability of selection. (20) Logistic
regression was used to examine the associations between various
independent variables and energy drink consumption. Separate two-way
interactions were used to test interactions involving the independent
variables and sex. Missing data were handled through listwise deletion.
Missing values did not exceed 4.8% for any of the variables examined and
the probability of energy drink consumption did not significantly differ
between missing and non-missing cases.
RESULTS
Demographic and behavioural characteristics of the sample are
outlined in Table 1 along with the prevalence of energy drink
consumption. Almost one half the sample was female, over 60% identified
themselves as White, and the average age of the sample was 15 years. One
half of adolescents reported that they consumed at least one energy
drink in the past 12 months--30.5% reported consumption in the past 12
months but not in the last 7 days, and an additional 19.1% indicated
consumption in the last 7 days. Those who drank one can or more each day
of the last 7 days represented 1.5% of the sample.
The results of bivariate analyses presented in Table 1 indicate
significant variations in energy drink consumption by each of the
demographic and behavioural characteristics examined. A slightly greater
percentage of males (22.6%) than females (15.2%) consumed energy drinks
in the last 7 days. Consumption also varied significantly by school
grade, with a greater proportion of adolescents in more senior grades
using energy drinks than those in more junior grades. In addition, there
were variations in consumption by ethnic background, with lower
percentages of adolescents who reported East, Southeast or South Asian
backgrounds consuming energy drinks. Energy drink consumption, both
12-month and 7-day, was more prevalent among adolescents who were
employed during the school year, who reported binge drinking, and who
used tobacco, cannabis, and non-medicinal prescription drugs than among
adolescents who did not engage in such behaviours. There were also
variations in consumption by sensation-seeking and injuries--e.g., 38.8%
of those who reported high sensation-seeking and 27.9% of those who
reported being injured and treated in the previous year had consumed
energy drinks in the previous week compared to 15.5% and 12.9% of those
who did not report high sensation-seeking and injury, respectively.
Results from multivariate logistic regression analyses that
examined energy drink consumption as a dichotomous measure of consumed
versus not consumed in the past year are outlined in Table 2. Model 1
included all covariates with the exception of sensation-seeking and
injury variables; model 2 included sensation-seeking and other
covariates, but not tobacco, cannabis, prescription drug use, and binge
drinking; and model 3 included all covariates. Findings were
substantively similar across models, with the exception of findings for
age that were not significant when drugs and alcohol were considered
within the model, but were significant when they were not included; and
East and Southeast Asian ethnic background which was no longer
significantly different from White after adjusting for all covariates in
model 3. Generally, model 3 results, with adjustments for all
covariates, indicate that neither age nor sex was significantly
associated with energy drink consumption. Analyses with grade level as a
covariate, instead of age, also indicated no significant association
with energy drink consumption (not presented). All other covariates,
however, were significantly associated with energy drink consumption.
The odds of energy drink consumption were significantly greater among
adolescents with less than an 80% average in school (OR=1.54, 95% CI
1.23-1.92), and among adolescents who worked for pay during the school
year (OR=1.38, CI 1.05-1.81), used tobacco (OR=1.74, CI 1.14-2.67), used
cannabis (OR=1.92, CI 1.34-2.75), used prescription drugs for
non-medicinal purposes (OR=1.54, CI 1.05-2.24), reported binge drinking
(OR=2.17, CI 1.58-2.98), reported high sensation-seeking behaviour
(OR=1.89, CI 1.38-2.59), and reported being hurt or injured and treated
medically in the past year (OR=1.56, CI 1.32-1.84). There was also a
significant association between ethnic background overall and
consumption (F(4, 163)=6.18, p<0.001), which is highlighted by
findings that adolescents of South Asian (OR=0.48, CI 0.32-0.72)
background were at significantly lower odds of consuming energy drinks
than were adolescents who reported being White.
Results from analyses testing differences in the correlates of
energy drink consumption for males and females were not statistically
significant, and thus these results are not presented.
DISCUSSION
Our findings indicate that 1 in 2 adolescents consumed at least one
can of energy drink within the previous year. This exceeds general
reports that approximately one third of adolescents consume energy
drinks, (11) but is generally consistent with prevalence reported among
college students. (19) The increasing popularity of energy drinks in the
last few years (1,2) would suggest that past-year use found in the
current study more accurately reflects current use. Almost 1 in 5
adolescents were found to have consumed energy drinks within the
previous week, a general indication of more frequent use.
Findings of this study indicate that, after adjusting for other
demographic and behavioural factors, the odds of consuming energy drinks
did not vary by sex or age. Consumption did, however, vary by ethnicity.
The odds of consuming energy drinks were lower among adolescents who
reported South Asian ethnic background compared to those who indicated
that they were White. Previous research on US college students also
indicated higher consumption among White students, but the comparison
was with Black students only. (17)
Adolescents who reported tobacco use, cannabis use or non-medicinal
use of prescription drugs in the previous year, or reported binge
drinking in the previous month, were at greater odds of having consumed
an energy drink. These findings are consistent with findings from
studies of college students that indicate that substance use behaviours
tend to cluster within individuals. (7,10,17-19) Although it cannot be
determined from these data whether binge drinking and energy drink
consumption occurred at the same time, about one third of adolescents
who reported binge drinking in the previous month also reported energy
drink consumption in the previous week, compared to only 14% of those
who did not report binge drinking. This highlights concerns about the
practice of mixing energy drinks with alcohol. Energy drinks, because of
their high caffeine content, are increasingly being mixed with alcohol,
often in an attempt to reduce feelings of alcohol intoxication. (11,29)
There is also evidence of mixing energy drinks with cannabis and
prescription drugs--13% of overall visits to US emergency departments
that related to energy drinks involved the mixing of energy drinks with
alcohol and 10% involved mixing with illicit drugs such as cannabis.
(16)
Current findings that high sensation-seeking (reported by 16% of
respondents) and recent injuries (reported by 42%) are associated with
energy drink consumption are consistent with research on college
students that found greater jock identity and risk-taking behaviours
among individuals who consume energy drinks. (10) Given the images of
extreme sports often portrayed in the marketing of energy drinks to
adolescents, these findings are of particular concern and should be the
focus of further research to determine the extent to which injury and
energy drink consumption coincide. This is of particular concern for
adolescents who may confuse energy drinks with sports drink--the latter
reduces dehydration, whereas the former may worsen it. (7,30)
Although the data for this study were derived from a province-wide
survey of adolescents in grades 7 through 12, there are several
limitations that are worth noting. First, the study is based on
cross-sectional data and so temporal order cannot be determined. Thus,
it is not clear whether substance use and other risk behaviours precede
energy drink consumption or vice versa. Second, the sample only consists
of students within the regular school system and thus approximately 7%
of adolescents are not represented. It may be that this excluded group
of adolescents, mostly from private and alternate schools, differs with
respect to energy drink consumption.
Given targeted marketing of energy drinks to adolescents, the ease
of availability, increasing popularity, and the association of energy
drink consumption with risky behaviours, there is an important need for
information about these beverages. (16) Safe levels of energy drink
consumption have not been established for adolescents, (5,7) although
some countries have taken steps to limit the level of caffeine in energy
drinks. (31) Whereas most adolescents who consume energy drinks are
unlikely to experience serious adverse effects, (17) the association
between energy drink consumption and injuries as well as drug use
indicates a need for greater awareness, particularly among parents and
health care providers, of the extent of energy drink consumption among
individual adolescents. In addition, there needs to be greater awareness
among the general public of the potential for associated health and
behavioural risks among adolescents who consume energy drinks.
Conflict of Interest: None to declare.
REFERENCES
(1.) Wolk BJ, Ganetsky M, Babu KM. Toxicity of energy drinks. Curr
Opin Pediatr 2012;24(2):243-51.
(2.) Meier B. F.D.A. posts injury data for 3 drinks. The New York
Times. November 15, 2012.
(3.) Reissig CJ, Strain EC, Griffiths RR. Caffeinated energy
drinks--A growing problem. Drug Alcohol Depend 2009;99(1-3):1-10.
(4.) Macdonald N, Stanbrook M, Hebert PC. "Caffeinating"
children and youth. CMAJ 2010;182(15):1597.
(5.) Health Canada. Food and nutrition: Caffeine in foods. Ottawa,
ON: Health Canada, 2012.
(6.) Babu KM, Church RJ, Lewander W. Energy drinks: The new
eye-opener for adolescents. Clin Pediatr EmergMed 2008;9(1):35-42.
(7.) Seifert SM, Schaechter JL, Hershorin ER, Lipshultz SE. Health
effects of energy drinks on children, adolescents, and young adults.
Pediatrics 2011;127(3):511-28.
(8.) Macdonald N, Hamilton R, Malloy P, Moride Y, Shearer J. Report
by the expert panel on caffeinated energy drinks. Ottawa: Health Canada,
2010.
(9.) Arria AM, O'Brien MC. The "high" risk of energy
drinks. JAMA 2011;305(6):600-1.
(10.) Miller KE. Wired: Energy drinks, jock identity, masculine
norms, and risk taking. J Am Coll Health 2008;56(5):481-90.
(11.) Simon M, Mosher J. Alcohol, Energy Drinks, and Youth: A
Dangerous Mix. San Rafael, CA: Marin Institute, 2007.
(12.) Sepkowitz KA. Energy drinks and caffeine-related adverse
effects. JAMA 2013;309(3):243-44.
(13.) Popkin B. The World Is Fat: The Fads, Trends, Policies, and
Products That Are Fattening the Human Race. New York, NY: Penguin Group,
2002.
(14.) Alford C, Cox H, Wescott R. The effects of Red Bull energy
drink on human performance and mood. Amino Acids 2001;21:139-50.
(15.) Smit HJ, Cotton JR, Hughes SC, Rogers PJ. Mood and cognitive
performance effects of "energy" drink constituents: Caffeine,
glucose and carbonation. Nutr Neurosci 2004;7(3):127-39.
(16.) Substance Abuse and Mental Health Services Administration,
Center for Behavioral Health Statistics and Quality. The DAWN Report:
Update on Emergency Department Visits Involving Energy Drinks: A
Continuing Public Health Concern. Rockville, MD: Drug Abuse Warning
Network, 2013.
(17.) Miller KE. Energy drinks, race, and problem behaviors among
college students. J Adolesc Health 2008;43(5):490-97.
(18.) Arria AM, Caldeira KM, Kasperski SJ, O'Grady KE, Vincent
KB, Griffiths RR, Wish ED. Increased alcohol consumption, nonmedical
prescription drug use, and illicit drug use are associated with energy
drink consumption among college students. J Addict Med 2010;4(2):74-80.
(19.) Arria AM, Caldeira KM, Kasperski SJ, Vincent KB, Griffiths
RR, O'Grady KE. Energy drink consumption and increased risk for
alcohol dependence. Alcohol Clin Exp Res 2011;35(2):365-75.
(20.) Paglia-Boak A, Adlaf EM, Mann RE. Drug Use Among Ontario
Students, 1977-2011: Detailed OSDUHS Findings (CAMH Research Document
Series No. 32). Toronto, ON: Centre for Addiction and Mental Health,
2011.
(21.) Courser MW, Shamblen SR, Lavrakas PJ, Collins D, Ditterline
P. The impact of active consent procedures on nonresponse and
nonresponse error in youth survey data: Evidence from a new experiment.
Eval Rev 2009;33:370-95.
(22.) White VM, Hill DJ, Effendi Y. How does active parental
consent influence the findings of drug-use surveys in schools? Eval Rev
2004;28(3):246-60.
(23.) Wechsler H, Nelson TF. Binge drinking and the American
college student: What's five drinks? Psychol Addict Behav
2001;15:287-91.
(24.) Johnston LD, O'Malley PM, Bachman JG, Schulenberg JE.
Monitoring the Future: National Survey Results on Drug Use, 1975-2010:
Volume I, Secondary School Students. Ann Arbor, MI: Institute for Social
Research, University of Michigan, 2011.
(25.) Freeman JG, King M, Pickett W, Craig W, Elgar F, Janssen I,
Klinger D. The Health of Canada's Young Children: A Mental Health
Focus. Ottawa: Public Health Agency of Canada, 2011.
(26.) Stephenson MT, Hoyle RH, Palmgreen P, Slater MD. Brief
measures of sensation seeking for screening and large-scale surveys.
Drug Alcohol Depend 2003;72:279-86.
(27.) Statistics Canada. Census 2006-2B (Long Form). Ottawa, 2006.
(28.) StataCorp. Stata Statistical Software: Release 12.0 [computer
program]. College Station, TX: StataCorp, 1985-2011.
(29.) Azagba S, Langille D, Asbridge M. The consumption of alcohol
mixed with energy drinks: Prevalence and key correlates among Canadian
high school students. CMAJ OPEN 2013;E19-E26.
(30.) Fogger S, McGuinness TM. Update on energy drinks and youth. J
Psychosoc Nurs Ment Health Serv 2011;49(12):17-19.
(31.) Health Canada. Health Canada's proposed approach to
managing caffeinated energy drinks. Ottawa, ON: Health Canada, 2011.
Available at: http://www.hc-sc.gc.ca/fn-an/legislation/pol/energy-drinks-boissons-energisantes-eng.php (Accessed March 25, 2013).
Received: April 17, 2013
Accepted: October 17, 2013
Hayley A. Hamilton, PhD, [1,2] Angela Boak, MA, [1] Gabriela Ilie,
PhD, [3,4] Robert E. Mann, PhD [1,2]
[1.] Centre for Addiction and Mental Health, Toronto, ON
[2.] Dalla Lana School of Public Health, University of Toronto,
Toronto, ON
[3.] St. Michael's Hospital, Toronto, ON
[4.] Department of Psychology, University of Toronto, Toronto, ON
Correspondence: Hayley Hamilton, Centre for Addiction and Mental
Health, 33 Russell St., Toronto, ON M5S 2S1, Tel: 416-535-8501, ext.
6353, Fax: 416-595-6068, E-mail: hayley.hamilton@camh.ca
Table 1. Energy Drink Consumption by Demographic and
Behavioural Characteristics
Not in Last Last 12
12 Months Months, but
n=2396 Not Last 7
Days n=1210
Sex F(1.38, 228.98)
= 3.6 *, ([dagger])
Male 47.8% 29.6%
Female 53.5 31.4
Grade F(4.46, 740.79) =
3.1 *, ([dagger])
7 65.7 20.5
8 58.2 23.4
9 51.4 28.1
10 51.0 29.1
11 43.4 35.1
12 41.7 39.3
Ethnicity F(5.38, 892.26) =
4.2 ***, ([dagger])
White 46.6 31.7
Black 55.6 27.3
East/SE Asian 64.1 25.4
South Asian 68.9 20.4
Other 49.1 31.4
Average school F(1.80, 299.16) =
marks 17.8 ***, ([dagger])
[greater 58.3 28.1
than or
equal to] 80%
<80% 41.8 33.0
Paid work F(1.80, 298.63) =
during school 16.9 ***, ([dagger])
No 55.5 28.2
Yes 40.6 35.1
Tobacco use F(1.87, 310.72) =
last 12 months 53.9 ***, ([dagger])
No 53.9 29.5
Yes 17.9 38.5
Cannabis use F(1.55, 257.42) =
last 12 months 84.6 ***, ([dagger])
No 58.9 27.0
Yes 23.7 41.4
Non-medicinal F(1.64, 271.57) =
use of prescription 24.9 ***, ([dagger])
drugs last 12 months
No 54.2 28.5
Yes 31.9 40.0
Binge drinking F(1.82, 302.84) =
last 4 weeks 56.7 ***, ([dagger])
No 58.8 27.5
Yes 23.1 40.2
High sensation- F(1.34, 221.62) =
seeking 24.0 ***, ([dagger])
No 54.3 30.2
Yes 28.3 32.8
Injured and F(1.96, 325.30) =
treated last 46.4 ***, ([dagger])
12 months
No 57.9 29.2
Yes 39.8 32.2
Age F(2,165) = 16.4 ***,
([double dagger])
Mean M=14.8 M=15.5
(95% CI) (14.7-15.0) (15.3-15.7)
Total % 50.4 30.5
(95% CI) (47.1-53.7) (28.2-32.8)
Last 7 Overall
Days Percent
n=736 of Sample
n=4342
Sex
Male 22.6% 53.2%
Female 15.1 46.8
Grade
7 13.8 13.3
8 18.4 13.9
9 20.5 16.7
10 19.9 16.8
11 21.5 16.3
12 19.1 23.0
Ethnicity
White 21.7 64.3
Black 17.2 5.8
East/SE Asian 10.5 10.5
South Asian 10.6 6.6
Other 19.5 12.9
Average school
marks
[greater 13.5 51.7
than or
equal to] 80%
<80% 25.2 48.3
Paid work
during school
No 16.3 65.0
Yes 24.2 35.0
Tobacco use
last 12 months
No 16.5 90.6
Yes 43.6 9.4
Cannabis use
last 12 months
No 14.1 76.6
Yes 35.0 23.4
Non-medicinal
use of prescription
drugs last 12 months
No 17.3 83.5
Yes 28.1 16.5
Binge drinking
last 4 weeks
No 13.8 76.8
Yes 36.6 23.2
High sensation-
seeking
No 15.5 84.0
Yes 38.8 16.0
Injured and
treated last
12 months
No 12.9 58.0
Yes 27.9 42.0
Age
Mean M=15.3 M=15.1
(95% CI) (15.0-15.6) (15.0-15.2)
Total % 19.1
(95% CI) (17.0-21.4)
*** p<0.001, ** p<0.01, * p<0.05.
([dagger]) Pearson Chi-Square adjusted for the survey design
and transformed into an F-statistic.
([double dagger]) Adjusted Wald test.
Table 2. Logistic Regression of Energy Drink Consumption (ED)
in Previous Year by Demographic and Behavioural Factors (n=3939)
(1) (2)
ED Regressed on ED Regressed on
Demographics Demographics,
and Drug Use Sensation-seeking
and Injury
Odds Ratio (95% CI) Odds Ratio (95% CI)
Age 1.00 (0.93-1.06) 1.12 (1.04-1.21)
Sex
Male 1.00 1.00
Female 0.77 (0.58-1.02) 0.84 (0.64-1.12)
Ethnicity
White 1.00 1.00
Black 0.81 (0.42-1.59) 0.75 (0.44-1.26)
East/SE Asian 0.63 (0.44-0.92) 0.57 (0.39-0.83)
South Asian 0.46 (0.31-0.70) 0.46 (0.30-0.70)
Other 0.85(0.55-1.31) 0.90 (0.57-1.41)
Average school
marks (<A)
[greater than 1.00 1.00
or equal
to] 80%
<80% 1.50 (1.19-1.89) 1.85 (1.47-2.32)
Paid work during
school year
No 1.00 1.00
Yes 1.46 (1.10-1.93) 1.46 (1.15-1.84)
Tobacco use
last 12 months
No 1.00
Yes 1.84 (1.20-2.80)
Cannabis use
last 12 months
No 1.00
Yes 2.15 (1.48-3.11)
Non-medicinal
use of prescription
drugs last 12 months
No 1.00
Yes 1.73 (1.23-2.44)
Binge drinking
last 4 weeks
No 1.00
Yes 2.35 (1.72-3.22)
High sensation-
seeking
No 1.00
Yes 2.71 (2.02-3.65)
Injured and
treated last
12 months
No 1.00
Yes 1.82 (1.56-2.12)
Constant 0.61 (0.23-1.63) 0.09 (0.03-0.28)
(3)
ED Regressed on
Demographics,
Drug Use,
Sensation-seeking
and Injury
Odds Ratio (95% CI)
Age 1.01 (0.95-1.08)
Sex
Male 1.00
Female 0.79 (0.60-1.04)
Ethnicity
White 1.00
Black 0.82 (0.43-1.58)
East/SE Asian 0.68 (0.46-1.00)
South Asian 0.48 (0.32-0.72)
Other 0.87 (0.57-1.34)
Average school
marks (<A)
[greater than 1.00
or equal
to] 80%
<80% 1.54 (1.23-1.92)
Paid work during
school year
No 1.00
Yes 1.38 (1.05-1.81)
Tobacco use
last 12 months
No 1.00
Yes 1.74 (1.14-2.67)
Cannabis use
last 12 months
No 1.00
Yes 1.92 (1.34-2.75)
Non-medicinal
use of prescription
drugs last 12 months
No 1.00
Yes 1.54 (1.05-2.24)
Binge drinking
last 4 weeks
No 1.00
Yes 2.17 (1.58-2.98)
High sensation-
seeking
No 1.00
Yes 1.89 (1.38-2.59)
Injured and
treated last
12 months
No 1.00
Yes 1.56 (1.32-1.84)
Constant 0.37 (0.14-1.01)
