Are somatic symptoms of depression better predictors of cardiac events than cognitive symptoms in coronary heart disease?

Several recent studies have found that somatic symptoms of depression predict cardiac events in patients with established coronary heart disease but cognitive symptoms of depression do not. However, other studies have not supported this finding, and the research in this area is complicated by methodological differences and inconsistencies in the classification of "cognitive" and "somatic" symptoms. In addition, somatic symptoms are more common than cognitive symptoms in cardiac patients and are often associated with more severe depression. These factors may confound the relationship between somatic symptoms and cardiac outcomes. Some reasons why somatic symptoms may be more common than cognitive symptoms in cardiac patients are considered, as well as whether somatic symptoms are likely to be symptoms of depression or of medical illness. Finally, some directions for future research are proposed.