The impact of long-term endurance sport participation (on top of a healthy lifestyle) on coronary atherosclerosis and acute cardiac events remains controversial. Some reports in the last decade have indicated that endurance athletes may have more coronary calcification, perhaps from the repeated stress of long exercise sessions.
A different composition of plaque called non-calcified or "soft" plaque is often present and may be more unstable and dangerous. To date no data has been available on the burden of "soft " plaque in endurance athletes compared with average exercises matched overall for clinical features.
A new study from Belgium provides detailed and somewhat shocking data.
The Master@Heart study is a well-balanced prospective observational cohort study. Overall, 191 lifelong master endurance athletes, 191 late-onset athletes (endurance sports initiation after 30 years of age), and 176 healthy non-athletes, all male with a low cardiovascular risk profile, were included. Peak oxygen uptake quantified fitness. The primary endpoint was the prevalence of coronary plaques (calcified, mixed, and non-calcified) on computed tomography coronary angiography. Analyses were corrected for multiple cardiovascular risk factors.
The median age was 55 years in all groups. Lifelong and late-onset athletes had higher peak oxygen uptake than non-athletes as would be expected.
Lifelong endurance sports was associated with having ≥1 coronary plaque, ≥ 1 proximal plaque (potentially more dangerous than a distal plaque), ≥ 1 calcified plaques, ≥ 1 calcified proximal plaque , ≥ 1 non-calcified plaque, ≥ 1 non-calcified proximal plaque (2.8X more likely), and ≥1 mixed plaque as compared to a healthy non-athletic lifestyle.
Lifelong endurance sport participation is not associated with a more favourable coronary plaque composition compared to a healthy lifestyle in men in their mid ages.
Lifelong endurance athletes had more coronary plaques, including more non-calcified plaques in proximal segments, than fit and healthy individuals with a similarly low cardiovascular risk profile.
Longitudinal research is needed to reconcile these findings with the risk of cardiovascular events at the higher end of the endurance exercise spectrum.
Generally, endurance athletes have a lower risk of heart events and good longevity. It is not time to quit or reduce exercise.
At a minimum, a heart calcium CT scan should be performed in endurance athletes by age 45-50, whether male or female. If abnormal, consideration for a coronary CT angiogram, as used in this study, should be entertained. Higher risk athletes can be treated with lifestyle, reversal supplements, and Rx medications if needed.