DEPRESSION AND THE COURSE OF CORONARY-ARTERY DISEASE

Literature and folk wisdom have long linked depression and death; howe ver, only recently have scientific studies examined the relation betwe en them. Beginning in the 1970s, investigators compared mortality amon g patients treated for major depression and the general population. Ni ne of ten studies found an increased mortality from cardiovascular dis ease among depressed patients. However; such studies confound the rela tion between depression and ifs treatment. Community surveys circumven t this difficulty, but as these studies began to appear, other investi gations revealed the strong association between depression and cigaret te smoking, which made obvious a need to control for smoking. The firs t study to do this appeared in 1993, and not only did a relation betwe en depression and mortality persist, but a relation between depression and the development of ischemic disease was revealed. In the past 2 y ears, six more community surveys have followed populations initially f ree of disease, and five have observed an increased risk of ischemic h eart disease among depressed persons. Another research strategy is to start with subjects who have preexisting cardiovascular disease. Here, too, depression has consistently been associated with a worse outcome . In one well-designed study, patients with depression in the period i mmediately after a myocardial infarction were 3.5 times more likely to die than nondepressed patients. The basis of this association remains speculative. However, it is likely that the changes in the autonomic nervous system and platelets that are seen in depression account for a substantial portion of the association.