A Research Letter was published in last week's Journal of the American Medical Association that provided updated information about the French experience with sports-related sudden cardiac death (SCD) in the general population. I've talked here at the blog previously about reporting by this group of investigators on their comprehensive study from 2011.
Last week's report focused on the time period from 2005 to 2010. The investigators identified cases of SCD during moderate to vigorous exercise among athletes who were primarily recreational, rather than competitive, athletes. Overall, 775 incidents of SCD were identified.
The incidence of sports-related SCD per million participants per year was:
2.96 for athletes aged 15-34
6.63 for athletes aged 35-54
7.51 for athletes aged 55-75.
and
5.45 for all athletes, overall.
But looking at gender, the incidence of sports-related SCD per million participants per year was:
10.07 for men
and only
0.51 for women.
During the study period, the 3 most common sports activities for women were cycling, jogging, and swimming. For those sports, the incidence of sports-related SCD per million participants per year were all less than 0.5. In contrast, the incidence of SCD for men in those sports was 6.5, 4.7, and 0.9, respectively.
Implications
There are at least a couple possible explanations. First, there may just be something different about men and women when it comes to predisposition to SCD. One obvious difference is the greater prevalence of coronary artery disease in adult men compared to women, but there may be other such differences as well. Another possibility is that, on a population basis, the intensity of exertion during participation might be different for men and women.
Regardless of the explanation, though, there is an implication with respect to screening. One of the criticisms of routine cardiac screening for young competitive athletes--yet alone, for recreational athletes--has been the limited resources and associated costs of physical examinations and diagnostic tests such as EKG's or echocardiograms. Knowing that the risk of sports-related SCD may be 10+ times greater for men than for women and several-fold greater for athletes older (rather than younger) than 35 years might help us focus our screening efforts on the portion of the recreational athlete population that is at greatest risk.