The Effects of Chronic Depression and Inflammation on Incident Type 2 Diabetes Mellitus in men

Background: Inflammation is a possible aetiological mechanism through which depression increases incident diabetes risk however there are few longitudinal studies. Methods: A cohort of 1,110 men aged 35 years or older underwent venous withdrawal for cardiometabolic risk factors, IL-6, CRP, and e-selectin at baseline and 5 year follow-up. Depression symptoms were assessed by CES-D or BDI-I, respondents were categorized into chronic or remitting depression. Logistic regression determined whether diabetes mellitus was associated with depression chronicity, inflammation, ? inflammation, and their interaction terms. Findings: There were 158 cases of incident diabetes (14.2%). The chronic depression and ? IL-6 interaction term was associated with greater diabetes risk (OR 2.36; 95% CI 1.28 – 4.36, p =.006). Chronic depression and ? e-selectin interaction term also significantly increased diabetes risk (OR 1.08; 95% CI 1.00 – 1.16, p =.05). Conclusions: These data provide support for inflammation as a biological mechanisms through which chronic depression increases diabetes risk.