Cardiac rehabilitation and physical activity decrease the risk of stroke after acute myocardial infarction: A nationwide cohort study in Sweden

BACKGROUND: Stroke and acute myocardial infarction (AMI) rank among the leading causes of mortality. Physical activity and exercise are recommended as part of rehabilitation after AMI to prevent cardiovascular events, but the importance for stroke prevention has not been investigated using population-based data. OBJECTIVES: To determine associations between participation in exercise-based cardiac rehabilitation (EBCR) and self-reported physical activity with the risk of total stroke, ischemic stroke, and intracerebral hemorrhage after AMI. METHODS: This was a nationwide, double cohort study conducted across all coronary care units in Sweden between 2005 and 2020, combined with registered data from the general population. Participation in EBCR (24 physiotherapist-led sessions over 4 months) and self-reported physical activity were assessed at a median of 55 days (range 28-90) after hospital discharge. Stroke incidence was followed until death or censoring on December 31, 2021. RESULTS: A total of 86,637 people with AMI (mean age 64.0, SD 9.0 years; 26 % female), and 259,911 (1:3) age, sex, and region of birth matched individuals from the general population were included. Participation in EBCR after AMI was associated with a lower risk of total stroke (adjusted hazard ratio, aHR 0.85; 95 % confidence interval, CI 0.80-0.91) compared to non-participants, as was ≥150 min of physical activity per week (aHR 0.79, 95 % CI 0.75-0.83). Those reporting physical activity 6 days per week after AMI did not have an increased risk of total stroke or ischemic stroke compared to the general population (aHR 1.03, 95 % CI 0.87-1.23; and aHR 1.17, 95 % CI 0.97-1.41), and were at lower risk of intracerebral hemorrhage (aHR 0.59, 95 % CI 0.35-0.98). CONCLUSIONS: EBCR and higher levels of physical activity are associated with a decreased risk of stroke after AMI. Cardiac rehabilitation programs and regular and physical activity should be promoted after AMI to decrease the burden of stroke. Swedish Ethical Review Authority Registration number: 2021-03645.