Abstract 2672: Depression is Associated with Decreased Coronary Flow Reserve Detected by Means of Positron Emission Tomography: A Twin Study
INTRODUCTION. Depression is associated with coronary heart disease, but the underlying mechanisms are controversial. Coronary flow reserve (CFR) in response to adenosine is an index of coronary microvascular dysfunction which predisposes to myocardial ischemia. We therefore examined the relationship between depression and
CFR. METHODS. We performed myocardial blood flow quantitation with [13N] ammonia positron emission tomography (PET) at rest and after adenosine stress in 130 male twins from the Vietnam Era Twin Registry who were born between 1946 and 1956 (mean age 54), were free of symptomatic CAD and had normal perfusion scans. CFR was measured as the ratio of maximum flow to baseline flow at rest. Current depressive symptoms were defined as a Beck Depression Inventory (BDI) ≥10. Lifetime history of major depression (MD) was determined with the Structured Clinical Interview for Psychiatry Disorders. Mixed-effect models were used to account for intra-pair variability and separate within- and between-pair effects. RESULTS. Of the participating twins, 21% had a BDI≥10, 25% had a lifetime history of MD, and 8% had both. Compared to non-depressed twins, CFR was lower in depressed twins, particularly those with history of MD: CFR was 2.1±0.8 in non-depressed twins, 1.9±0.6 in twins with BDI≥10 but without MD, and 1.6±0.3 in twins with BDI≥10 and MD (P=0.01). These results were still significant after adjusting for traditional CVD risk factors (systolic blood pressure, BMI, LDL-cholesterol, diabetes, smoking and physical activity). Within pairs, the adjusted CFR was 2.1 in twins with BDI≥10 and 1.6 in co-twins with BDI≥10 (p=0.008).
CONCLUSIONS. Depression is associated with decreased coronary flow reserve in persons without obstructive coronary disease, suggesting that microvascular dysfunction might play a role in increasing CVD risk in depression.