Depression as a risk factor for cardiac events in established coronary heart disease: a review of possible mechanisms.

Depression is highly prevalent in patients with coronary heart disease (CHD) and is associated with excess medical morbidity and mortality. This article reviews the mechanisms which may mediate the relationship between depression and cardiac events in these patients. Research in this area is at an early stage of development. However, there is evidence that altered autonomic tone, smoking, hypertension, and, at least in older patients, poor adherence to the cardiac treatment regimen may be responsible for the adverse cardiac effects of depression.