Physical Activity and Mortality among Male Survivors of Myocardial Infarction

Physical Activity and Mortality among Male Survivors of Myocardial Infarction: Purpose

An inverse association between physical activity (PA) and risk of coronary heart disease has been seen in many studies, but evidence for benefits of PA after myocardial infarction (MI) in reducing mortality is limited.

Methods

Using data from the Health Professionals Follow-up Study cohort, we followed male survivors of MI. Short term and long term changes in PA from before to after MI were calculated, and participants without ambulation impairment were classified into maintained low, decreased, increased, or maintained high PA categories. Cox models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for mortality across PA and PA change categories.

Results

During a mean of 14 years of follow-up of 1651 incident non-fatal MI cases, we documented 678 deaths, 307 were due to CVD. Adjusted HRs for all-cause mortality comparing ≥ 21 with ≤ 1.5 METs/week of PA before MI was 0.73; (95% CI, 0.59-0.89; Ptrend=0.03). Compared with men who maintained low PA before and after MI, men who maintained high PA had a 39% (95% CI, 25-50) lower risk of all-cause mortality, and those who had a long-term increase in PA from before to after MI had a 27% (95% CI, 6-43) lower risk. Walking for ≥ 30 minutes/day after MI was associated with a 29% lower mortality (HR=0.71; 95% CI, 0.58-0.84), independent of walking pace, and walking pace after MI was inversely associated with mortality (HR=0.67; 95% CI, 0.49-0.92).

Conclusions

Maintaining a high PA or having a long-term increase in PA from before to after MI was associated with lower mortality among male MI survivors. Walking time and walking pace after MI were each inversely associated with mortality.

Correspondence to: Walter C. Willett, MD, Dr.Ph, Department of Nutrition, Harvard T.H. Chan School of Public Health, 655 Huntington Avenue, Boston, MA 02115, USA, Phone: 617.432.4680. Email: wwillett@hsph.harvard.edu

The cohorts were supported by grants of UM1 CA167552, and R01 HL35464 from the National Institutes of Health. The results of the study are presented clearly, honestly, and without fabrication, falsification, or inappropriate data manipulation. The authors assume full responsibility for analyses and interpretation of these data. The results of the present study do not constitute endorsement by ACSM. Laila Al-Shaar received research support from the American Heart Association (17PRE33660133).

Conflict of Interest: The authors have no conflict of interest.

Accepted for Publication: 3 February 2020.

© 2020 American College of Sports Medicine