Underdiagnosis of Depression in Patients with Coronary Artery Disease: The Role of Nonspecific Symptoms

Abstract

Objective: To determine whether the underdiagnosis of major depression (MD) in patients with coronary artery disease (CAD) may be explained by low specificity and mild severity of depressive symptoms in affected patients. Method: The Beck Depression Inventory (BDI) was used to assess depression symptoms in thirty-one patients with both CAD and MD, and eighty-three patients with CAD but without MD. Results: Only ten (48%) of the symptoms were significantly more common in the MD than in the non-MD group, and nine symptoms were present in at least 20 percent of both groups. Of these nine nonspecific symptoms, only one (insomnia) was more severe in the MD patients than in the non-MD group ( p < .006). When all twenty-one symptoms were rank ordered by frequency, the most common symptoms in the MD group were also the most common in the non-MD group ( r = .91, p < .001). Conclusions: The symptoms of major depression were found to be relatively mild and nonspecific in patients with CAD. This may help to explain why depression is underdiagnosed in cardiac patients.