Depression and coronary heart disease: observations and questions.

The evidence that depressive symptomatology precedes the onset of the acute coronary syndromes and influences the course of disease after their manifestation is accumulating. However, we still are far short of proof that depression has a causal role in the etiology and pathogenesis of coronary heart disease (CHD). Some unsolved questions concern the causes and the nature of the depression preceding a first or recurrent cardiac event, the biological mechanisms relating depression and CHD, the time window of the exposure-disease association, and the power of therapy programs for depression to reduce the risk of a first or recurrent cardiac event.