LAUSR

OBJECTIVE Depression and coronary heart disease (CHD) are highly comorbid conditions. Brain-derived neurotrophic factor (BDNF) plays an important role in cardiovascular processes. Depressed patients typically show decreased BDNF concentrations. We analyzed the relationship between BDNF and depression in a sample of patients with CHD, and additionally distinguished between cognitive-affective and somatic depression symptoms. We also investigated whether BDNF was associated with somatic comorbidity burden, acute coronary syndrome (ACS), or congestive heart failure (CHF). METHODS The following variables were assessed for 225 hospitalized patients with CHD: BDNF concentrations, depression (Patient Health-Questionnaire-9), somatic comorbidity (Charlson Comorbidity Index), CHF, ACS, platelet count, smoking status, antidepressant treatment. RESULTS Regression models revealed that BDNF was not associated with severity of depression: Although depressed patients (PHQ-9 score >7) had significantly lower BDNF concentrations compared to non-depressed patients (p=.04), this was not statistically significant after controlling for confounders (p=.15). Cognitive-affective symptoms and somatic comorbidity burden each closely missed a statistically significant association with BDNF concentrations (p=.08, p=.06, respectively). BDNF was reduced in patients with CHF (p=.02). There was no covariate-adjusted, significant association between BDNF and ACS. CONCLUSION Serum BDNF concentrations are associated with cardiovascular dysfunction. Somatic comorbidities should be considered when investigating the relationship between depression and BDNF.