DETERMINANTS OF VO2PEAK IN CHRONIC HEMIPARETIC STROKE PATIENTS

Abstract

2062 Hemiparesis contributes to a loss of muscle mass and a reduction in walking velocity after stroke. Self-selected floor walking speed (SSWS) is an index of gait recovery after stroke. The purpose of this study was to determine whether peak oxygen consumption (VO2PEAK) is associated with body composition and gait recovery in chronic hemiparetic stroke patients approximately 40 months after ischemic stroke. Twenty-six patients (22 males, 5 females), aged 66± 9 years (mean ± SD), completed a progressive graded treadmill test until fatigue to measure VO2PEAK (1.3 ± 0.4 L/min) and a 30 foot walking test to determine SSWS (1.4 ± 0.7 mph). Percent body fat (30.4 ± 10.6%), total lean mass (52.0 ± 9.3 kg), leg lean mass (17.2 ± 3.7 kg), and thigh lean mass (13.2 ± 2.7 kg) were determined by DEXA. VO2PEAK correlated with total lean mass (r=0.60), leg lean mass (r=0.58), affected leg lean mass (r=0.55), thigh lean mass (r=0.64), and SSWS (r=0.53, all p < 0.01). VO2PEAK did not correlate with percent body fat and latency after stroke. In a stepwise linear regression of total lean mass, leg lean mass, thigh lean mass, affected leg lean mass, and SSWS, both thigh lean mass (r=0.61, p<0.001) and SSWS (cumulative r =0.79, p<0.001) were independent predictors of VO2PEAK and explained 67% of the variance. These results indicate that muscle mass and gait recovery are important determinants of physical performance in the older chronic stroke patient. Supported by NIH/NIA P60-AG12583, NIH/NIA 1R29AG14487-01