Depression Predicts Elevated Endothelin-1 in Patients with Coronary Artery Disease

Objectives—Depression carries an independent 2- to 4-fold increased risk of early morbidity and mortality after acute coronary syndrome (ACS). The pathway(s) linking depression to eventfree survival remain to be determined. We examined the relationship of depression severity to circulating endothelin-1 (ET-1), which has previously been linked to plaque rupture and post-ACS survival. Methods—Patients with documented history of coronary artery disease (n=101) provided a resting morning blood sample that was assayed for ET-1, and completed the Beck Depression Inventory (BDI). ET-1 was treated as a log transformed continuous variable (logET-1), and as a dichotomous variable using a post-ACS risk threshold previously reported (≥1.16 fmol/ml). Results—BDI score was related to logET-1 in both unadjusted and adjusted models. In addition, unadjusted and adjusted logistic regression models with dichotomous ET-1 revealed that for each point increase in BDI score there was approximately a 14% increased likelihood of being at or above ET-1 risk threshold. Secondary logistic regression models demonstrated a greater than 3.5fold likelihood of being at or above this risk threshold in association with a BDI score ≥10. Conclusions—Depression symptom severity predicts ET-1 elevation that has previously been linked to post-ACS survival, with the greatest risk of elevation among those with worse depression symptoms. This link may identify a vulnerability to triggered ACS and poorer survival associated with depression. Future research should establish whether the observed relationship of depressive symptoms to ET-1 level mediates the link between depression and survival.