Depression and platelet activation in outpatients with stable coronary heart disease: Findings from the Heart and Soul Study

Depression is associated with increased morbidity and mortality in patients with coronary heart disease (CHD). Increased platelet activation has been proposed as a potential mechanism by which depression may lead to adverse cardiovascular outcomes. In this cross-sectional study, we measured platelet activation in 104 patients with stable CHD, including 58 with a current episode of major depression and 46 without past or current major depression. Participants were instructed not to take aspirin for 7 days prior to the study appointment. Platelet activation was measured by plasma concentrations of platelet factor 4 (PF4) and beta-thromboglobulin (β-TG), and by 24-h urinary concentrations of 11-dehydro-thromboxane B₂ (TBXB2). We observed no differences in the mean levels of PF4, B-TG or TBXB2 in patients with and without major depression. Results were unchanged after adjustment for age, smoking, use of aspirin, and use of any psychotropic medication. We found no evidence of an association between major depression and platelet activation as measured by plasma concentrations of PF4 and β-TG, or urinary TBXB2 in 104 outpatients with stable CHD. These findings do not support a role for platelet activation in the association between depression and cardiovascular disease among patients with stable CHD.