Physical inactivity is highly associated with mortality, especially in patients with coronary heart disease. We evaluated the effect of perceived health competence, a patient's belief in his or her ability to achieve health-related goals, on cumulative physical activity levels in the Mid-South Coronary Heart Disease Cohort Study. The Mid-South Coronary Heart Disease Cohort Study consists of 2,587 outpatients (32% were female) with coronary heart disease at an academic medical center network in the United States. Cumulative physical activity was quantified in metabolic equivalent (MET)-minutes per week with the International Physical Activity Questionnaire. We investigated associations between the 2-item Perceived Health Competence Scale (PHCS-2) and MET-minutes/week after adjusting for co-morbidities and psychosocial factors with linear regression. Nearly half of participants (47%) exhibited low physical activity levels (<600 MET-minutes/week). Perceived health competence was highly associated with physical activity after multivariable adjustment. A nonlinear relation was observed, with the strongest effect on physical activity occurring at lower levels of perceived health competence. There was effect modification by gender (p = 0.03 for interaction). The relation between perceived health competence and physical activity was stronger in women compared with men; an increase in the PHCS-2 from 3 to 4 was associated with a 73% increase in MET-minutes/week in women (95% confidence interval 43% to 109%, p <0.0001) compared with a 53% increase in men (95% confidence interval 27% to 84%, p <0.0001). In conclusion, low perceived health competence was strongly associated with less physical activity in patients with coronary heart disease and may represent a potential target for behavioral interventions.
Published by Elsevier Inc.