Correlates of compliance in a randomized exercise trial in myocardial infarction patients.
OBJECTIVE
Exercise-based rehabilitation programs have been associated with decreased morbidity and mortality after myocardial infarction. Unfortunately, attendance is often poor, and information is limited regarding predictors of long-term compliance to such programs. This study examined factors associated with exercise session compliance over 3 yr in male myocardial infarction (MI) survivors.


METHODS
Subjects were participants in the National Exercise and Heart Disease Project, a 3-yr (1976-1979) multicenter, randomized clinical trial (N = 651); 308 men, 30-64 yr of age, were randomized to the exercise treatment group, that met three times/week throughout the study. Compliance was defined as the number of sessions attended/number of sessions conducted. Patient characteristics at enrollment were considered as possible predictors of compliance.


RESULTS
Compliance decreased as time since enrollment increased with the largest decrease observed after the first 8 wk. Compliance correlated positively with exercise test measures [last completed stage (r = 0.17, P < 0.01), peak heart rate (r = 0.11, P = 0.06)], high density lipoprotein (HDL) cholesterol (r = 0.15, P = 0.10), age (r = 0.11, P = 0.07), and inversely with body mass index (r = -0.19, P = 0.001), sum of three skinfolds (r = -0.15, P < 0.01), total cholesterol (r = -0.18, P < 0.01), triglycerides (r = -0.16, P < 0.01), and depression (r = -0.09, P < 0.11). Current smokers were less compliant than former and nonsmokers (r = -0.21, P < 0.001). The correlations with last completed stage, BMI, skinfolds, total cholesterol, and smoking status were statistically significant. The model explained 22.2% of the variance in compliance (r2 = 0.222). Baseline work capacity was among the most consistent predictors of early and late compliance.


CONCLUSIONS
Compliance decreased over time. Men already at high risk for repeat events due to elevated risk factors were less compliant. These findings have important clinical implications regarding screening, intervention, and participation in potential cardiac rehabilitation program dropouts.
Dorn
J
J
Department of Social and Preventive Medicine, University at Buffalo, NY 14214, USA. jdorn@acsu.buffalo.edu
Naughton
J
J
Imamura
D
D
Trevisan
M
M
D000328:Adult; D017677:Age Distribution; D000428:Alcohol Drinking / Q000453:epidemiology; D015992:Body Mass Index; D002784:Cholesterol / Q000097:blood; D003327:Coronary Disease / Q000453:epidemiology; D003863:Depression / Q000453:epidemiology; D005080:Exercise Test / Q000706:statistics & numerical data; D005081:Exercise Therapy / Q000706:statistics & numerical data*; D017079:Exercise Tolerance; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology / Q000534:rehabilitation*; D010349:Patient Compliance / Q000706:statistics & numerical data*; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology; D012959:Socioeconomic Factors; D013223:Statistics as Topic; D013997:Time Factors
D002784:Cholesterol