OBJECTIVE: This study aimed for a comprehensive evaluation of major depressive disorder (MDD) in stable coronary heart disease (CHD) patients, excluding all other potential psychiatric comorbidities, and including associations with cardiac biomarkers such as C-reactive protein (CRP), troponin T (TnT), and amino-terminal pro-B-type brain natriuretic peptide (NT-proBNP). METHODS: Cross-sectional study of a consecutive series of 72 stable CHD outpatients (n=30 with MDD, n=42 with no psychiatric disorder). Psychiatric diagnoses were established by using the Structured Clinical Interview for DSM-IV (SCID), and psychiatric assessment was performed on Axis I, Axis III, Axis IV, and Axis V. Regression analyses were performed including CRP, TnT, and NT-proBNP as dependent variables, and MDD, demographics, and comorbid medical conditions as independent variables. RESULTS: Stepwise multiple regression analyses showed a significant association between MDD and CRP (beta=0.262, P=.02), excluding all other demographic and medical variables from the models, except age (beta=0.266, P=.02). In addition, the results described a significant relationship between type II diabetes mellitus and TnT (beta=0.267, P=.02), and age and NT-proBNP levels (beta=0.374, P=.001). CONCLUSION: Major depressive disorder was associated with elevated CRP levels in a consecutive series of stable CHD patients.