The effect of walking and vitamin B supplementation on quality of life in community-dwelling adults with mild cognitive impairment: a randomized, controlled trial

OBJECTIVES: To examine the effect of walking and vitamin B supplementation on quality-of-life (QoL) in community-dwelling adults with mild cognitive impairment. METHODS: One year, double-blind, placebo-controlled trial. Participants were randomized to: (1) twice-weekly, group-based, moderate-intensity walking program (n = 77) or a light-intensity placebo activity program (n = 75); and (2) daily vitamin B pills containing 5 mg folic acid, 0.4 mg B12, 50 mg B6 (n = 78) or placebo pills (n = 74). QoL was measured at baseline, after six and 12 months using the population-specific Dementia Quality-of-Life (D-QoL) to assess overall QoL and the generic Short-Form 12 mental and physical component scales (SF12-MCS and SF12-PCS) to assess health-related QoL. RESULTS: Baseline levels of QoL were relatively high. Modified intention-to-treat analyses revealed no positive main intervention effect of walking or vitamin supplementation. In both men and women, ratings of D-QoL-belonging and D-QoL-positive affect subscales improved with 0.003 (P = 0.04) and 0.002 points (P = 0.06) with each percent increase in attendance to the walking program. Only in men, SF12-MCS increased with 0.03 points with each percent increase in attendance (P = 0.08). CONCLUSION: Several small but significant improvements in QoL were observed with increasing attendance to the walking program. No effect of vitamin B supplementation was observed. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number Register, 19227688, http://www.controlled-trials.com/isrctn/.