심지영, 박성하, 최동훈, 양우인, 조인정, 고영국, 장양수, 정남식, 하종원 |
Background: Although obesity is associated with arterial stiffening, the dynamic changes of arterial stiffness during exercise in overweight subjects have not been studied. We hypothesized that overweight would be associated with a dynamic arterial stiffening during exercise.
Methods: The multistage (25 Watt, 3 minutes increments), symptom-limited, supine bicycle exercise testing was performed in 44 overweight women, defined as a body mass index (BMI) between 25 and 30 kg/m2, and 48 lean women (BMI < 25.0 kg/m2). Central arterial hemodynamics including central aortic pressure and augmentation index (AIx) were obtained at rest as well as at peak exercise using radial artery tonometry.
Results: At rest, there were no significant differences in the augmentation pressure (lean vs. overweight; 18±10 vs. 20±8, p = 0.290), AIx (37.5±11.7 vs. 38.2±10.2 %, p = 0.754) and AIx normalized for heart rate 75/min (AIx@75; 32.5±11.7 vs. 33.3±9.3 %, p = 0.716) between 2 groups. Despite similar exercise duration, however, the augmentation pressure (10±9 vs. 18±12, p < 0.001), AIx (17.7±14.5 vs. 27.7±13.9 %, p = 0.001) and AIx@75 (28.4±13.7 vs. 35.5±9.3 %, p = 0.018) at peak exercise were significantly higher in the overweight women. In simple correlation analysis, BMI revealed significant correlations with augmentation pressure, AIx, and AIx @75 at peak exercise whereas no relationship was found with the resting parameters. Multiple regression analysis showed that BMI was an independent determinant of AIx at peak exercise (β = 0.21, p = 0.028). In aspects of left ventricular remodeling, overweight women showed a high prevalence of left ventricular hypertrophy (40.9 vs. 14.6 %, p = 0.020) than lean subjects.
Conclusion: Overweight is related with dynamic arterial stiffening during exercise and left ventricular remodeling in nondiabetic women.
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