Clinical Medicine Insights: Cardiology

Objective: To assess the effects of exercise on resting heart rate (RHR), weight, lipid profile, and blood pressure. We hypothesized that the participants who increased their physical activity would show improvement in their cardiovascular risk factors compared to those who did not.

Design: Retrospective chart review over the mean duration of 4.9 years of follow-up.

Setting: Healthy Heart Program Prevention Clinic at St. Paul's Hospital, Vancouver, British Columbia, Canada.

Participants: We reviewed 300 charts of patients randomly selected from those who attended the Prevention Clinic between 1984 and 2009. 248 (82.7%) patients were referred for primary prevention and 52 (17.3%) for secondary prevention.

Primary and secondary outcome measures: Weight, RHR, lipid profile, and blood pressure were recorded at the initial and last visit.

Results: During a mean of 4.9 years of follow-up, 55% of participants improved their exercise. The mean decrease in the RHR for these patients (group 1) was 5.9 beats per minute (bpm) versus the mean increase of 0.3 bpm for the “no change” group (group 2) (P < 0.01). The mean net weight increase in group 1 was 0.06 kg/year versus 0.25 kg/year in group 2. Because of medications, all patients had a significant improvement in their lipid profiles. Furthermore, there was a statistically significant greater reduction in Framingham Risk Score (FRS) in group 1 versus group 2 (11.8% versus 15.1%, P < 0.01).

Conclusion: Participation in the program significantly reduces modifiable risk factors for cardiovascular disease. Improved exercise regimen results in lower RHR and greater reduction in FRS. However, even in a Prevention Program, despite strong advocacy of the importance of exercise, a significant percentage of participants does not improve their exercise habits.