Background and Aims: Physical activity recognized as both a modifiable and independent risk factor for coronary heart disease (CHD). Most cardiac patients are insufficiently active to meet Canadian guidelines for aerobic exercise. The Tracking Exercise After Cardiac Hospitalization (TEACH) study identified that the rate of decline in physical activity is greatest between 2 and 6 months post-hospital discharge and plateaus thereafter. Good intervention designs require knowledge of the behavioral factors that influence participation in physical activity in this patient population over time. Knowledge of these factors and their relative importance could help tailor interventions appropriately at strategic time points. Therefore, the present study examined behavioral predictors of activity energy expenditure (AEE) at 2, 6 and 12 months post-discharge in CHD patients.
Methods: Eight hundred and one CHD patients (61.4 years; 75% males, 25% females) who participated in the TEACH study were included in the present study. Predictors of activity (outcome expectations, perceived competence, task and barrier self-efficacy, social support, anxiety, depression) and AEE (physical activity recall) were assessed in-hospital, and 2, 6 and 12 months after hospitalization.
Results: Zero-order correlations were performed between AEE and demographic variables using the Bonferonni correction method. Results showed that age, gender, education, employment, income, co-morbidities and cardiac rehabilitation participation were significantly related to AEE. Next, a hierarchal liner regression was performed. The demographics were entered into block 1 and the AEE predictors into block 2. Predictors accounted for 6.3%, 8.1% and 8.6% of the variation in AEE respectively at 2, 6 and 12 months. Specifically, task self-efficacy (B=.13, p<.05) and friend companionship (B=-.01, p<.05) at 2 months, barrier self-efficacy (B=-.10, p<.05) at 6 months and outcome expectations (B=.10, p<.05), barrier self-efficacy (B=-.10, p<.05), expert esteem (B=.16, p<0.5) and inhibitive support (B=-.16, p<0.1) at 12 months had a unique association with AEE.
Conclusions: Results from the current study highlight the varying effect of behavioral predictors in AEE. Noting that the greatest decline in AEE is between 2 and 6 months and plateaus thereafter, interventions should be intensified during these time points specifically focusing on the identified predictors above. Health care professionals assisting patients post cardiac diagnosis should capitalize on these time points and predictors of AEE in an effort to improve physical activity levels in this population.