Socio-economic differences in diabetes mortality: a Brussels-Capital Region follow-up study (2001-05)

Hadewijch Vandenheede, Vrije Universiteit Brussel
Lies Lammens, Vrije Universiteit Brussel
Patrick Deboosere, Vrije Universiteit Brussel

Objective The aim of this study is to identify socio-economic (SE) differences in premature diabetes mortality in men and women aged 25 to 74. To capture the real burden of diabetes, both death certificates with diabetes as underlying (UCOD) and multiple (MCOD) cause of death (any mention of diabetes) are analysed. Methods The data consist of a cohort study linking the 2001 census to emigration and mortality data for the period 2001-05. The study population comprises all inhabitants of the Brussels-Capital Region aged 25-74 (N=598,578). The total number of diabetes-related deaths is 720. Indicators of socio-economic status (SES) are educational attainment (immaterial dimension) and housing quality (material dimension). Age-adjusted mortality rates are calculated using direct standardisation. Diabetes mortality rate ratios (MRR) are obtained through Poisson regression models. Results Overall, a lower SES is associated with higher diabetes mortality. According to the indicator of SES used, the strength of the association differs. In men, an inverse educational gradient is observed. Men with primary or no formal education have a MRRMCOD of 2.4 (95% CI 1.8-3.3) compared to those who attained higher education. In women, the lowest educated - primary or no formal education - have a 6 times higher RR of dying from diabetes compared to women with higher education (RRMCOD=6.0; 95% CI 3.2-11.3). However, the relation between education and diabetes mortality is not linear. Further analyses point in the direction of an exclusion mechanism. A linear gradient between housing quality and diabetes mortality is observed for both men and women. In women, the gradient is steeper than in men. Conclusion The results of this study show considerable SE differences in diabetes mortality. Health interventions targeting both the gradient and the most disadvantaged groups are necessary to avoid premature diabetes mortality.