"Major" Depressive Disorder, coronary heart disease, and the DSM-IV threshold problem

Seventy-seven patients with documented coronary heart disease (CHD) were evaluated for demographic/risk factor characteristics, Major Depressive Disorder (MDD) according to the Patient's Health Questionnaire (PHQ - Diagnostic and Statistical Manual IV criteria), and emotional distress by the Symptom Checklist 90-Revised (SCL-90-R). Early age at initial diagnosis for coronary heart disease (AAID) was used as a proxy for disease malignancy because early AAID is a known predictor of early mortality. MDD was unrelated to early AAID despite being strongly associated with all the scales of the SCL-90-R. Several of the SCL-90-R scales were significantly associated with early AAID in the sample as a whole (Depression, Interpersonal Sensitivity, Anxiety, Paranoia, and Psychoticism) and after removal of the patients meeting criteria for MDD (residual N = 54). Our results suggest a new criterion for determining whether depression, or any mental disorder, is "major": onset or aggravation of serious medical illness.