Educational inequalities in the metabolic syndrome and coronary heart disease among middle-aged men and women

Background: Previous studies have shown socioeconomic inequalities in the metabolic syndrome and coronary heart disease (CHD), but it is not known whether educational disparities in the metabolic syndrome explain educational inequalities in CHD. We investigated this question in a prospective study of middle-aged men and women. Methods: Baseline data were collected in 1992 in Finland from 864 men and 1045 women aged 45-64 years without history of CHD. A total of 113 new CHD cases were identified by the end of 2001. Logistic and Cox regression models were used in data analysis. Results: The metabolic syndrome defined by NCEP criteria was less prevalent in subjects with university education (21% in men and 14% in women) compared with basic level education (41% and 27%, respectively). Adjusting for health behavioural factors had only a slight effect on the educational gradient in the metabolic syndrome. An educational gradient in CHD incidence was clear [hazard ratio (HR) = 0.67 95% confidence interval (CI) 0.48-0.94, men and women combined]. Adjustment for the metabolic syndrome attenuated this gradient only slightly, but when individual components of the metabolic syndrome were included as covariates the attenuation was more substantial (HR = 0.73 95% CI 0.52-1.04). Conclusions: Educational differences in the metabolic syndrome and CHD incidence are clear. Metabolic risk factors explain the gradient in CHD incidence partly, but only when they are treated as independent risk factors. Screening for the metabolic syndrome alone is not sufficient to account for socioeconomic inequalities in cardiovascular disease.