Behavioral differences and effects of cardiac rehabilitation in diabetic patients following cardiac events

PURPOSE: TO describe the incidence of depression and other behavioral disorders in diabetic coronary patients following major cardiac events and to assess the impact of cardiac rehabilitation. PATIENTS: 291 consecutive coronary patients (70 with diabetes mellitus). METHODS: Patients were prospectively enrolled in comprehensive phase II cardiac rehabilitation 4 to 6 weeks following a major cardiac event. Depressive symptoms and other behavioral characteristics (anxiety, somatization, hostility), as well as parameters of quality of life, were assessed by validated questionnaires at entry and upon completion (12 weeks, 36 sessions) of cardiac rehabilitation. RESULTS: Diabetic patients made up 24% of the cohort and were more likely to be female (P = 0.08), hypertensive (P = 0.05), and obese (P = 0.08). Additionally, diabetic patients had a reduced exercise capacity (P = 0.008), lower high-density lipoprotein cholesterol (P = 0.008), lower low-density lipoprotein cholesterol (P = 0.02), and increased triglyceride (P = 0.04) levels. Diabetic patients had a higher incidence of depression (26% versus 14%; P < 0.03), demonstrated more symptoms of somatization (P < 0.06), and exhibited lower scores for components of quality of life. Following cardiac rehabilitation, the incidence of depression was reduced in diabetic patients by 67% (P = 0.01) and ultimately equaled the 9% prevalence found in the non-diabetic group. CONCLUSIONS: Diabetic coronary patients demonstrate a higher incidence of depression than non-diabetic patients following major cardiac events. In addition to improving traditional cardiac risk factors, cardiac rehabilitation reduces depression in this high-risk group.