The effect of clinical characteristics and dietary habits on the relationship between education status and 5-year incidence of cardiovascular disease: the ATTICA study

Objective The aim of this work was to investigate whether clinical characteristics and dietary habits influence the association between education status and 5-year incidence of cardiovascular disease (CVD). Methods From 2001 to 2002, 1,514 men and 1,528 women (> 18 year) without known CVD were enrolled. In 2006, the 5-year follow-up was performed (31% participants were lost to follow-up). Development of fatal or non-fatal CVD (coronary heart disease, acute coronary syndromes, stroke, or other CVD) was defined according to WHO-ICD-10 criteria. Education status was measured in years of school, while baseline dietary habits were assessed through a semi-quantitative food-frequency questionnaire (EPIC-Greek). The Mediterranean-Diet-Score was applied to assess overall adherence to this pattern using scores of 11 food-variables and alcohol, according to the principles of the Mediterranean-diet. Results The 5-year incidence of CVD was 108 (11.0%) cases in men and 62 (6.1%) cases in women (P < 0.001); 32 (1.6%) of these events were fatal (21 in men). People in the low education group had significantly higher prevalence of hypertension, diabetes, and dyslipidemias, were more likely to be sedentary and smokers, compared to high group. Moreover, compared to high, people in low education group had less healthy dietary habits, as assessed using the diet score (P < 0.001). Multi-adjusted analysis revealed that low education was positively associated with 5-year incidence of CVD, after adjusting for age and sex (HR = 1.64; 95%CI 1.05-2.55); however this association lost its significance when clinical characteristics and dietary habits were taken into account (HR = 1.31; 95%CI 0.63-2.74). Conclusions Low education seems to increase CVD risk, an observation that was partially explained by baseline clinical characteristics and unhealthy dietary choices of people belonging into this group.