This next study is from the same Barcelona group that published the Mont et al. paper and the Elosua et al. one. This, however, is an entirely different cohort of subjects.
Participants in the 1990 Barcelona marathons were invited to participate in a health survey (unrelated to the topic of atrial fibrillation). A total of 252 runners agreed. Age range at entry was 20-60. Of these, 183 agreed to participate in a follow-up examination in 2002-03, on average 11 years after the initial marathon.
The controls were selected from a near contemporaneous, unrelated study of 802 subjects (age range 25-74) performed in the Barcelona region. All subjects who were sedentary (< 305 kcal/day of leisure activity) were selected. That made up a group of 305 subjects. Of these, 290 agreed to respond at the 2003-03 follow-up. The study design is below:
Click to enlarge
Despite being younger and leaner than the control group, the group of marathoners had a higher rate of atrial fibrillation (prevalence ~ 5% among marathon runners). Note: consumption of alcohol was greater among marathon runners…
Click to enlarge
The authors then compared the marathon runners with AF compared to those without AF. There was no identifiable clinical or echocardiographic difference at the baseline visit. At the follow-up visit, LA dimension was greater in the fibbers (chicken or egg?).
The data tables are below.
Main take-home lesson: the study solidifies the increased risk of AF in athletes. Still no distinguishing predictive baseline characteristics and no real handle on whether any monitoring can identify athletes on the verge of developing significant AF (the paper by Furlanello et al. suggested AF could be reversed if caught early and activity level is decreased)
Click to enlarge
Click to enlarge
Print This Post
I’m convinced that there is an increase in af in endurance athletics as much as I would like the data to be otherwise.
James
I agree, James. It is also apparent (particularly if you look at the 3 major studies: Finnish orienteer, Tour de Suisse, and this one) that although AF can and does occur at a relatively young age, prevalence increases with age, so we’re probably not just dealing with a subset of subjects who are susceptible to AF, but there is also a cumulative effect over time.
In the Tour de Suisse study there was no increase in PAC’s or “proto-SVT’s” in the athletes compared to the control group, which suggests (but does not rule out) that periodic monitoring may not be all that helpful. There are additional studies coming up that look more at atrial size. We’ll see…