The status of depression associated with macrovascular and microvascular comorbidities in patients with long-duration type 2 diabetes

Background Psychologic distress, including depression, is a common problem in patients with type 2 diabetes mellitus (T2DM). However, how depression severity relates to vascular complications in T2DM remains uncertain. Methods This study analyzed 1187 patients with long-duration T2DM (mean diabetes duration: 14.0 ± 8.5 years) and 3289 newly diagnosed T2DM patients from the Taiwan Diabetes Registry. Depression severity was assessed using the self-report Patient Health Questionnaire-9, categorized into minimal (score 0–4), mild (score 5–9), and moderate to severe (score ≥ 10). Diabetes associated vascular complications were evaluated through medical record reviews and physical examinations, and their associations with depression severity were analyzed using logistic regression analysis. Results In patients with long-duration T2DM, higher depression severity was associated with an increased prevalence of cardiovascular disease, peripheral arterial occlusive disease (PAOD), and neuropathy (p -values of 0.002, 0.025, and 0.003, respectively). After adjusting for multiple variables, mild and moderate to severe depression were both linked to a heightened risk of cardiovascular disease and PAOD, with adjusted odds ratios (OR) of 2.92 (95% CI: 1.45 to 5.86) and 2.91 (95% CI: 1.24–6.83), respectively. Mild depression was linked to polyneuropathy (OR: 1.89, 95% CI: 1.23–2.88). In newly diagnosed T2DM patients, depression prevalence was lower, and moderate to severe depression was associated with microvascular risks, specifically retinopathy (adjusted OR: 1.78, 95% CI: 1.16–2.76) and nephropathy (adjusted OR: 1.48, 95% CI: 1.04–2.09). Conclusion In T2DM, depression associates with macrovascular and neuropathic complications in long-duration disease, but microvascular conditions at diagnosis. Psychological screening should be tailored to disease duration.