摘要：Objectives. We assessed the impact of education level on the association between self-rated health and cardiovascular risk factors (blood pressure, glycosylated hemoglobin level, and total cholesterol and triglyceride levels). Methods. We used data from the National Health and Nutrition Examination Survey for the years 2001 through 2004 (4015 men and 4066 women). Multivariate analyses were performed with a logistic regression model. Results. After adjustment for age and ethnicity, among women with high glycosylated hemoglobin levels, the most-educated women had poorer self-rated health compared with the least-educated women (odds ratio [OR] = 4.61; 95% confidence interval [CI] = 2.90, 7.34 vs OR = 2.59; 95% CI = 1.60, 4.20, respectively; interaction test, P = 0.06). The same was true among women with high cholesterol levels (OR = 2.23; 95% CI = 1.40, 3.56 vs OR = 1.13; 95% CI = 0.85, 1.49, respectively; interaction test, P = 0.06). Among men, the impact of education level on the association between self-rated health and any cardiovascular risk factors (measured or self-reported) was not significant. Conclusions. The impact of cardiovascular risk factors on self-rated health was higher for highly educated women, which could lead to underestimation of health inequalities between socioeconomic groups when self-rated health is used as an indicator of objective health. Self-rated health is a useful measure of health status because it is a consistent predictor of mortality, is easy for researchers to use, and refers to a broad, multidimensional definition of health. 1 As a result, it is commonly used to study social inequalities in health 2 ; however, this use can be problematic. The way people rate their health depends on their expectations of what their health should be, which in turn may be associated with their socioeconomic status. In many instances, researchers have reported that people are more likely to compare themselves with people they are socially similar to. 3 , 4 Studies have reported that socially advantaged groups might have higher expectations about their quality of life and health 5 ; they may therefore feel that a particular illness has a greater negative impact on their health than do less socially advantaged people, for whom expectations are lower. This phenomenon could lead to an underestimation of the health inequalities that exist between socioeconomic groups when self-rated health is used as an indicator of health. In a study comparing socioeconomic inequalities in health across 22 European countries, Mackenbach et al. showed that although the relative index of inequality (defined as the ratio of the estimated mortality or morbidity prevalence among people with the lowest education level to that among people with the highest education level, where education level is a proxy for socioeconomic status) was greater than 1 for both mortality and self-assessed health, it was higher for mortality (almost 2.2 for men and 1.8 for women) than for self-reported health (only about 1.4 for both men and women). 6 When mortality rather than self-assessed health was used as the outcome, the magnitude of the variations in the index of inequality across countries was also higher. Three recent reports have shown some evidence for a modifying effect of socioeconomic status on the relationship between self-rated health and mortality. 7 – 9 Studies on this topic are still uncommon, 10 however, and to our knowledge, little work has investigated how socioeconomic status might modify the association between objective health status and self-rated health. One of the main challenges in conducting this kind of study is the definition and measure of “objective” health status, which is frequently measured from self-reports—making health status not truly objective—and is potentially influenced by how questions are answered in the same way as self-rated health. 11 We assessed the overall impact of level of education on the link between self-rated health and health status as evaluated by biological indicators (blood pressure, glycosylated hemoglobin level, and cholesterol and triglyceride levels) in a representative sample of the noninstitutionalized US population.
