To evaluate whether depression
is associated with whole blood serotonin
in outpatients with stable coronary heart disease
is associated with incident CHD and with adverse cardiovascular outcomes. Dysregulation of peripheral serotonin, common to both depression
and CHD, may contribute to this association.
We performed a cross-sectional study of 791 participants with stable CHD enrolled in the Heart and Soul Study and not taking antidepressant medication. We assessed major depression
using the Computerized Diagnostic Interview Schedule (CDIS-IV) and measured whole blood serotonin
(WBS) from fasting venous samples.
Of the 791 participants, 114 (14%) had current (past month) major depression
, 186 (24%) had past (but not current) major depression
, and 491 (62%) had no history of depression
. Age-adjusted mean WBS was higher in participants with current major depression
(139 ± 6.5 ng/ml) than in those with past depression
(120 ± 5.0 ng/ml) or no history of depression
(119 ± 3.1 ng/ml) (p
= .02). This association was unchanged after adjustment for demographic characteristics, medical comorbidities, medication use, and cardiac disease severity (p
= .02). When serotonin was analyzed as a dichotomous variable, current depression
was associated with a 70% greater odds of having WBS in the highest quartile (adjusted odds ratio = 1.71; 95% Confidence Interval = 1.03–2.83; p
In this sample of patients with stable CHD, current major depression
was independently associated with higher mean WBS levels. Future studies should examine whether elevated WBS may contribute to adverse outcomes in patients with depression
CHD = coronary heart disease; CDIS = computerized diagnostic interview schedule; HPLC = high pressure liquid chromatography; LVEF = left ventricular ejection fraction; MI = myocardial infarction; WBS = whole blood serotonin; 5-HT1 = 5-hydroxytryptophan 1; 5-HT2 = 5-hydroxytryptophan 2.