The Association Between Major Depression and Levels of Soluble Intercellular Adhesion Molecule 1, Interleukin-6, and C-Reactive Protein in Patients With Recent Acute Coronary Syndromes

OBJECTIVE: This study was conducted to determine whether or not depression is associated with higher levels of inflammatory markers in patients recovering from acute coronary syndromes. METHOD: Plasma levels of soluble intercellular adhesion molecule 1 (sICAM-1) and interleukin-6 (IL-6) and the serum level of C-reactive protein were measured in 481 patients 2 months after hospitalization for acute coronary syndromes. Diagnosis of major depression was based on the Structured Clinical Interview for DSM-IV. RESULTS: Depressed patients showed significantly higher sICAM-1 levels, a difference that remained significant after adjustment for potential confounders (gender, smoking, presence of metabolic syndrome). Although there was no significant association between depression and IL-6, there was an interaction between depression and statin therapy for levels of C-reactive protein. Depressed patients not taking statins had markedly higher C-reactive protein levels than did nondepressed patients. There was no relationship with depression in those receiving statins. CONCLUSIONS: These results suggest chronic endothelial activation among depressed patients after acute coronary syndromes. Further research is needed to determine whether or not higher levels of sICAM-1 may identify a subgroup of depressed patients at particularly high risk for cardiac events among patients with established coronary artery disease or among those without previous coronary artery disease.