Abstract 3962: Advanced-Age Marathon Runners Have A Reduced Framingham Risk Score But Their Extent of Coronary Atherosclerosis is Underestimated
Background: Coronary atherosclerosis is the main cause of exercise-associated death in older athletes. Routine screening for cardiovascular disease is, however, currently not recommended. In this study we measured the prevalence and extent of cardiovascular risk factors (RF) and of coronary artery calcium (CAC) in advanced-age marathon runners in comparison to matched controls from an unselected general population.
Methods: Male marathon runners (n=108, inclusion criteria: age >50 yrs, at least 5 marathon races (42.195km) during the previous 5 yrs, no known heart disease, no diabetes) were invited to participate. Standard RF were measured to calculate the Framingham risk score (FRS). CAC (Agatston score) was measured using electron beam CT. Marathon runners were matched 4:1 by age (n=424) and 2:1 by age and RF (n=216) with asymptomatic presumably healthy males from the Heinz Nixdorf Recall Study (HNRS), an ongoing population-based trial on the predictive value of established RF and novel imaging modalities.
Results: The marathon runners (57±7 yrs) had completed 20 marathons starting 9 yrs ago. On 5 exercise sessions per week they covered 55km per week (median values). RFs were improved in marathon runners in comparison to age-matched controls (BMI: 24±2 (-14%), systolic blood pressure: 121±14 (-10%), LDL-cholesterol: 120±29 (-18%), HDL-cholesterol: 74±17 (+42%) (mean±SD (%-reduction vs. HNRS-cohort), p<0.01 each), resulting in a significant reduction of FRS (7.0±3.6 (-49%), p<0.001). Yet, marathon runners had a similar CAC burden as age-matched controls (Q1/median/Q3 = 0/36/217 vs. 3/40/159, p=n.s.). A CAC>100, indicating increased cardiovascular risk, was more frequent in marathon runners (36.2%) than in age- and RF-matched controls (22.2%, p<0.003).
Conclusion: Regular marathon running in males >50 yrs reduces the Framingham risk score by almost 50%. This favourable risk profile did not match the extent of subclinical atherosclerosis but was much higher compared to age- and RF-matched controls from the general population. This unexpectedly high coronary athero-sclerotic burden may account for some of the exercise-related cardiac events in advanced-age marathon runners.