Abstract 19338: Marathon Runners Have Increased Arterial Stiffness and Intima-Media Thickness: Implications for Cardiovascular Risk
Objective: Marathon running represents an aerobic, vigorous and competitive exercise. Aortic stiffness and wave reflections are independent predictors of cardiovascular risk. Increased Intima Media Thickness represents an early marker for development of structural changes of the arterial wall. We assessed the effect of marathon running on the elastic properties of the large arteries and on IMT.
Methods: A subgroup of the study comprised 49 marathon runners (14.97±3.67 hours/week for 11.6±9.1 years) (42 males, mean age: 38±9yrs) and 46 matched controls (aerobic exercise <3 hours/week), (40 males, mean age: 37±5yrs). Aortic stiffness was evaluated with carotid-femoral pulse wave velocity (PWV) and wave reflections with augmentation index (AIx) of the aortic pressure waveform. Another subgroup comprised 23 marathon runners (13.5±2.5 hours/week for 10.4±7.2 yrs) (19 males, mean age: 38±9 yrs) and 23 matched controls (aerobic exercise <3 hours/week) (19 males, mean age: 39±7 yrs). IMT was measured with high resolution B-mode ultrasonography of the common carotid wall.
Results: Marathon runners had significantly higher systolic, diastolic, pulse (aortic and brachial) and mean pressures compared to controls (p<0.05 for all). Heart rate was reduced in athletes (P=0.05). PWV was increased in athletes (6.9±1 vs. 6.3±1, P<0.01), indicating increased aortic stiffness. AIx and AIx corrected for heart rate did not differ among the two groups (13.8% vs 13.9% and 8.2% vs 10.3% respectively, p=NS). In multivariable regression analysis mean pressure and intensity of exercise were independent determinants of PWV (adjusted R2=0.293, p<0.001 and p<0.05 respectively), indicating that higher intensity of training increases arterial stiffness. Athletes exhibited higher carotid IMT compared to controls (0.62±0.11 mm vs 0.56±0.07 mm, P=0.03).
Conclusions: Marathon runners have increased aortic stiffness, increased central and peripheral haemodynamic parameters, as well as increased carotid IMT compared to controls. The latter may represent an adaptive process following the long-term exposure to elevated systemic pressures during intense exercise. These findings could contribute to precisely assess the overall cardiovascular risk in marathon runners.
- © 2010 by American Heart Association, Inc.