Purpose: We measured extracoronary atherosclerotic plaque burden and its association with cardiovascular risk factors and with coronary atherosclerosis in male marathon runners.
Methods: We studied 100 male presumably healthy runners, aged 50-75 yr, who completed at least five marathons during the preceding 3 yr. Presence of plaque in the carotid, abdominal, and lower limb arteries was imaged using B-mode ultrasound. In all runners, traditional cardiovascular risk factors and the electron beam computed tomography-based coronary artery calcium (CAC) score were determined.
Results: Ten runners were free from any plaque in the carotid or peripheral arteries. Runners with plaque were older (58 ± 6 vs 54 ± 5 yr, P = 0.04), had a higher 10-yr Framingham risk score (7.2 ± 3.8 vs 5.0 ± 1.9, P = 0.026), and tended to have a higher prevalence of CAC (76.7% vs 50.0%, P = 0.07) compared with those without. Runners with CAC ≥ 100 had larger peripheral artery diameters (aorta and iliac and common femoral arteries) but smaller lumen than runners with CAC < 100, indicating atherosclerotic remodeling. A stepwise model selection process to predict CAC on the basis of age and peripheral atherosclerosis yielded a model as follows: log2(CAC + 1) = 0.181 age (yr) + 0.435 maximum carotid plaque thickness (mm) − 6.487, with a coefficient of determination of 22.8%. However, positive and negative predictive values were too low to predict CAC ≥ 100 with sufficient accuracy.
Conclusions: The prevalence of carotid and peripheral atherosclerosis in marathon runners is high and is related to cardiovascular risk factors and the coronary atherosclerotic burden. Remodeling of peripheral arteries is greatest in runners with the most evidence of atherosclerosis. These data support an increased awareness of atherosclerosis prevalence and cardiovascular risk factors in marathon runners.