Background: This study examined whether mild-to-moderate depressive symptoms are associated with increased high-sensitivity C-reactive protein (hsCRP) and interleukin 6 (IL-6) levels in apparently healthy individuals at high risk for coronary artery disease. We investigated in individuals whether: (1) current depressive symptoms were associated with increased hsCRP and IL-6 levels; (2) persistent depressive symptoms at two time points 6 months apart were associated with hsCRP and IL-6; and (3), sex-based differences in inflammation were a function of depressive symptoms. Methods: We measured depressive symptoms (twice), hsCRP, and IL-6 (follow-up time point) in 84 apparently healthy individuals (52% women) at high cardiac risk. Results: Patients with persistent depressive symptoms had higher hsCRP, compared to participants without persistent symptoms (5.55 vs. 1.70 mg/l, p < 0.05, 95% CI 0.11 to 1.09, d = 0.67). Participants with current depressive symptoms had higher hsCRP (3.99 vs. 1.70 mg/l, p = 0.059) than those without symptoms. Findings remained unchanged after controlling for covariates. Women had higher adjusted hsCRP than men (2.91 vs. 1.87 mg/l, p < 0.001). When we entered depressive symptoms, the model remained significant, with a significant interaction between sex and symptoms: women with depressive symptoms had higher hsCRP than men with depressive symptoms and than women without symptoms (6.75 vs. 1.11 mg/l). The hypothesized differences were not observed with respect to IL-6, after controlling for body mass index (95% CI−0.77 to 0.73). Conclusions: Before a first ischaemic coronary event, persistent mild-to-moderate depressive symptoms were associated with increased hsCRP. Women with depressive symptoms had higher hsCRP than men with symptoms.
Serum Myeloperoxidase Levels Are Associated With the Future Risk of Coronary Artery Disease in Apparently Healthy Individuals
