Longitudinal differences in aerobic capacity between children with sickle cell anemia and matched controls

The purpose of this study was to compare longitudinal trajectories of maximal aerobic capacity in children with sickle cell anemia (SCA) and matched healthy controls, and explore whether these trajectories were associated with selected physiologic variables. Children with SCA (n = 33) and healthy controls (n = 30) matched at baseline for race, sex, Tanner stage, height, and weight completed three consecutive annual fitness assessments (VO2peak ). Data were compared between the groups at each time point and within groups over time. Change in VO2peak between the two groups over time was assessed using a linear mixed model with age, sex, fat-free mass (FFM), Tanner stage, and hemoglobin (Hgb) concentration as covariates. At baseline, children with SCA had significantly lower Hgb concentration (8.9 vs. 13.7 g/dL, P < 0.001) and relative VO2peak (24.2 vs. 27.9 ml/kg/min, P = 0.006) than healthy controls. Over time, children with SCA had smaller increases than healthy controls in VO2peak (-0.1 and +4.9 ml/kg/min, P < 0.001), Tanner stage at year 2 (15% and 66% Tanner 4, P < 0.001), and FFM (+4.0 and +6.8 kg, P = 0.02). Changes in Hgb concentration did not differ between groups (+0.03 and +0.09 g/dL, P = 1.0). After adjusting for age,...Continue Reading