Physical performance and Vitamin D in elderly black women-the PODA randomized clinical trial

Context: There is limited information on the influence of vitamin D on physical performance in black Americans. Objective: To determine if maintenance of serum 25(OH)D>75 nmol/L prevents a decline in physical performance. Design: The Physical Performance, Osteoporosis and Vitamin D in African American Women (PODA) trial had a prospective, randomized, placebo controlled, double-dummy design with two arms: one of which is placebo vitamin D₃ adjusted to maintain serum 25(OH)D >75 nmol/L. Patients: The target population was healthy elderly black women with serum 25(OH)D between 20 and 65 nmol/L. The trial was 3 years in duration with measurement of physical performance every 6 months: grip strength, Short Physical Performance Battery (SPPB), 10 chair rises, and 6-minute walk distance. A total of 260 women entered the study and 184 completed 3 years. Mean age was 68.2 years. Baseline 25(OH)D was 53 nmol/L; total SPPB was 11 (10 to 12). Setting: Research center in an academic health center. Main Outcomes Measure: Prevention of decline in physical performance measures. Intervention: Participants were randomly assigned to placebo or active vitamin D. Vitamin D3 dose was adjusted to maintain serum 25(OH)D >75 nmol/L. Results: There was a decline with time in grip strength and the 6-minute walk test. The SPBB increased with time. There were no substantial differences between the placebo and active vitamin D₃ groups with respect to the temporal patterns observed for any of the performance measures. Conclusion: There is no benefit of maintaining serum 25(OH)D>75 nmol/L in preventing the decline in physical performance in healthy black American women.