Low physical activity level may confer risk for instant, short-term MI death
Moderate to high physical activity levels were associated with lower risk for instant and 28-day death related to MI, according to results published in the European Journal of Preventive Cardiology.
“Less myocardial stunning, less ischemia-induced arrhythmias, improved left ventricular function and improved survival after a cardiac arrest have been documented in patients hospitalized with MI who experience pre-infarction angina; an equivalent of ischemic preconditioning,” Kim Wadt Hansen, MD, PhD, postdoctoral research fellow in the department of cardiology at Bispebjerg Frederiksberg University Hospital in Copenhagen, Denmark, and colleagues wrote. “Despite this strong biological basis for a cardioprotective effect of physical activity, prospective studies on the relation between physical activity and risk for death during the acute phase of a MI are scarce.”
For a collaborative pooled analysis of 10 European cohort studies, researchers assessed 28,140 patients with an incident MI, a baseline physical activity assessment, conventional CV risk factors and available data on MI and death. The participants were stratified by weekly physical activity level: sedentary (< 7 metabolic equivalents of task [MET] hours), low (7-16 MET hours), moderate (16.1-32 MET hours) or high (> 32 MET hours) based on an individual’s calculated net weekly energy expenditure.
The primary outcome was instant and 28-day fatality related to MI.
Of the 4,976 participants who died within 28 days, 3,101 (62.3%) were classified as instant fatal MI. Participants with low (OR = 0.79; 95% CI, 0.6-1.04), moderate (OR = 0.67; 95% CI, 0.51-0.89) or high (OR = 0.55; 95% CI, 0.4-0.76) levels of physical activity demonstrated lower adjusted odds for instant fatal MI compared with patients with sedentary physical activity levels. The results suggest individuals with moderate and high physical activity levels had a 33% and 45% lower risk for instant MI fatality, the researchers wrote.
Researchers observed similar results for 28-day fatal MI among patients with low (OR = 0.85; 95% CI, 0.71-1.03), moderate (OR = 0.64; 95% CI, 0.51-0.8) or high (OR = 0.72; 95% CI, 0.51-1) levels of physical activity compared with sedentary patients. In the analysis of instant fatal MI, researchers found a low to moderate degree of heterogeneity (I2 = 47.3%) but not in analysis of 28-day fatal MI (I2 = 0%).
According to a press release from the European Society of Cardiology, based on these findings, even a low amount of leisure-time physical activity may be beneficial against fatal MI, but statistical uncertainty prevents the researchers from providing definitive conclusions.
“Our pooled analysis provides strong support for the recommendations on weekly physical activity in healthy adults stated in the 2016 European Guidelines on CVD prevention in clinical practices, especially as we used cutoff values for physical activity comparable to those use in the guidelines,” the researchers wrote. “We believe that our findings may be helpful to all health providers in their consultancy of healthy adults.”