Depression and 24-hour urinary cortisol in medical outpatients with coronary heart disease: The Heart and Soul Study

Background In patients with coronary heart disease (CHD), depression leads to worse cardiovascular outcomes. Depression has been associated with increased cortisol in medically healthy patients, suggesting that cortisol may act as a mediator in the pathway between depression and cardiovascular events. However, it is not known whether depression is associated with elevated cortisol levels in patients with CHD. Methods We examined the association between depression (assessed by the Computerized Diagnostic Interview Schedule) and 24-hour urinary cortisol in 693 medical outpatients with known CHD. Results Of 693 participants, 138 (20%) had current depression. Depressed participants had greater mean cortisol levels than those without depression (42 ± 25 vs. 36 ± 20 μg/day, p< .01). With each increasing quartile of cortisol concentration the frequency of depression increased (p< .01). Participants in the highest quartile of cortisol had a twofold increased odds of having depression, compared with those in the lowest quartile (odds ratio [OR] 2.1, 95% confidence interval [CR] 1.2-3.6, p = .01). This association remained strong after adjusting for potential confounding variables (OR 2.4, 95% CI 1.3-4.4, p< .01). In this cross-sectional analysis, elevated cortisol was not associated with worse cardiac function. Conclusions In patients with CHD,depression is associated with elevated cortisol levels.