Socioeconomic inequalities in the incidence and prevalence of type 2 diabetes mellitus in Europe.

Objective: The aim of this study was to analyze socioeconomic position (SEP) inequalities in the prevalence and incidence of type 2 diabetes mellitus (T2DM) in people aged 50 years and over in Europe and to describe the contribution of body mass index (BMI) and other possible mediators.

Methods: This was a cross-sectional and longitudinal study including men and women ≥ 50 years old in 11 European countries in 2004 and 2006 (n = 21,323). The prevalence and cumulative incidence of T2DM were calculated with self-reported T2DM or when the individual took drugs for diabetes. Prevalence ratio (PR) and relative risk (RR) of prevalent and incident T2DM were calculated according to educational level and adjusted by BMI and other possible mediators.

Results: The age-adjusted and country-adjusted prevalence of T2DM in 2004 was 10.2% in men and 8.5% in women. Compared to those with higher education, men and women with lower education had a PR [95% CI] of T2DM of 1.29 [1.12-1.50] and 1.61 [1.39-1.86], respectively. SEP-related inequalities in incidence (RR [95%CI]) were 1.88 [1.35-2.62] in women and 1.04 [0.78-1.40] in men. Adjusting for potential mediators reduced inequalities in the prevalence and incidence of T2DM among women by 26.2% and 21.6%, respectively, and inequalities in prevalence among men by 44.8%.

Conclusions: We observed significant inequalities in the prevalence and incidence (women only) of T2DM as a function of socioeconomic position. These inequalities were mediated by BMI.