Carotid intima-media thickness progression and plaque formation in recreational male endurance athletes - a 10-year follow-up study

Abstract Background Lifelong endurance exercise is associated with increased arteriosclerosis and, in particular, an accelerated rate of coronary artery calcification (CAC) and higher plaque burden. The mechanisms underlying the progression of CAC remain incompletely understood. Purpose We aimed to determine the potential pathomechanism for carotid artery plaque formation or accelerated carotid intima-media thickness (cIMT) progression in recreational male endurance athletes after a follow-up of 10 years. Methods Middle-aged (43±8 years) former participants (healthy male marathon runners) of the Beer, Marathon, Genetics, Inflammation, and the Cardiovascular System (Be-MagIC) study who ran10 km/week or cycled 20 km/week and participated in 5 endurance competitions during the last 10 years underwent baseline and 10-year morphological assessment using carotid ultrasound. Sporting characteristics were assessed via a questionnaire and cardiopulmonary exercise tests. Plaque formation and cIMT progression were defined as follows: Plaque at baseline and/or after 10 years of follow-up. Progression in cIMT was calculated from baseline to 10-year follow-up. Linear and logistic regression analyses were performed to determine the association between age, body fat, resting systolic blood pressure, fasting glucose, total cholesterol at baseline, loading systolic blood pressure max. at 10-year follow-up, km per week during the last 10 years and cIMT progression/plaque formation. Results A total of 96 former male marathon runners were included. Former runners ran for a median of 30 interquartile range, IQR 20-40 km per week and participated in an average of 26 (min-max: 5–508) endurance events during the last 10 years. After 10 years, the V02peak amounted to 42.8±7.9 mL/min/kg. cIMT increased from 0.57mm 0.51 – 0.66mm to 0.62mm 0.55 – 0.73mm (p0.001) after 10 years. Plaque was present in 21% at baseline and 37% after 10 years (p0.001). In total, 20% of the previous plaque-free participants developed new plaque during the 10-year follow-up. No significant association in the progression of cIMT with the investigated variables was observed (Figure 1). Plaque formation showed an independent significant association with age, body fat, and km per week (odds ratio 95%CI: 1.24 1.12 to 1.36, p0.001; 1.15 1.02 to 1.31, p=0.019 and 0.97 0.94 to 0.99, p=0.016, respectively, Figure 1). Furthermore, no indications of non-monotonic correlations were found. Conclusion The mean progression of cIMT in male recreational athletes was 0.05mm per year. The percentage change of plaque in recreational endurance athletes after 10 years was 76%. Furthermore, age, body fat, and km per week were associated with plaque progression during the 10-year follow-up in male endurance athletes.