Physiological and Psychological Variables Predict Compliance to Prescribed Exercise Therapy in Patients Recovering from Myocardial Infarction

Abstract
Previous research has documented high rates of noncompliance to prescribed medical therapy in patients recovering from myocardial infarction (MI). This study was undertaken to determine if patients who subsequently drop out of a structured cardiac rehabilitation program could be prospectively distinguished from those who remain in the program based upon their initial baseline characteristics. Thirty-five consecutive patients with recent MIs underwent comprehensive physical and psychological assessments at entry into the program, and were followed for a period of 1 year. The 14 patients who dropped out of the program could be distinguished from the compliers on the basis of their reduced left ejection fraction assessed by first pass radionuclide angiography at rest and during peak exercise. In addition, their psychological profiles assessed by the MMPI indicated the dropouts were more depressed, hypochondriacal, anxious, and introverted and had lower ego strength than those who remained in the program. Statistical analysis further indicated that psychological variables were associated with noncompliance independently of physical status. These findings suggest that MI patients who are unlikely to adhere to this form of medical therapy may be prospectively identified based upon their initial physical and psychological characteristics.