Depressive symptoms and sub-clinical atherosclerosis in Africans: role of metabolic syndrome, inflammation and sympathoadrenal function

Depressive symptoms have been consistently associated with sub-clinical atherosclerosis and future risk of coronary heart disease events. However, the pathways linking depression and coronary atherosclerosis are poorly understood. These types of data are particularly sparse in sub-Saharan Africa, which is presently experiencing an exponential rise in CVD. We examined the association between depressive symptoms and mean carotid intima media thickness (mCIMT), and the extent to which this association could be explained by sympathoadrenal function, inflammatory, and metabolic pathways. A sample of 186 black (aged 44.0 ± 8.0 years) and 203 Caucasians (aged 44.8 ± 10.8 years) were recruited as part of the Sympathetic Activity and Ambulatory Blood Pressure in Africans (SABPA) study — presently the only study in sub-Saharan Africa focusing on the contribution of the psychosocial risk factors to cardiovascular health. Depressive symptoms were assessed using the self administered 9-item Patient Health Questionnaire. After adjusting for age, sex, ethnicity, and anti-hypertensive drugs use, participants with severe depressive symptoms had higher mCIMT in comparison to participants with no symptoms (β = 0.038 mm, 95% CI, 0.001 to 0.074 mm). Metabolic syndrome was the only significant mediator of the association between depressive symptoms and mCIMT, and accounted for approximately 21% of the effect. In summary, depressive symptoms were associated with an excess burden of sub-clinical vascular disease. Treatment of metabolic syndrome in patients with depression may partly reduce the risk of sub-clinical vascular disease development