Cholecalciferol and muscle strength in hemodialysis patients: results from the randomized VITADIAL trial

Abstract Background Many factors contribute to muscle impairment during chronic kidney disease, within which vitamin D deficiency has been involved. The aim of this study was to analyze if cholecalciferol supplementation in hemodialysis patients with low 25-OH vitamin D (25OHD) concentrations could improve handgrip strength. Methods VITADIAL is a prospective open-labeled French multicenter study in which chronic hemodialysis patients with a 25OHD ≤ 50nmol/L were randomized to receive monthly oral 100.000 IU cholecalciferol or no vitamin D treatment during 6 months to assess if cholecalciferol supplementation in vitamin D deficient hemodialysis patients improves muscle strength as measured with handgrip strength (HGS). The main objective of the study was to analyze if a 6-month period of oral cholecalciferol improved the muscle strength of hemodialysis patients with low 25OHD levels. Results Within the 270 hemodialysis patients from 10 hemodialysis centers included in the study 143 patients with 25OHD ≤ 50nmol/L were randomized: 70 were allocated to the cholecalciferol group and 73 to the control group. The two groups were comparable at inclusion. The cholecalciferol supplemented group’s 25OHD raised to 89.78±33.43 nmol/L at 6 months and remained ≤50 nmol/L for most patients of the control group, but HGS did not change significantly between randomization and end of the study in both groups (0.07±3.40kg and -0.19±3.35kg respectively, p-value 0.682). No difference was found neither in terms of autonomy and frailty. Conclusions This highly powered study did not find any effect of cholecalciferol supplementation in muscle strength of hemodialysis patients with low 25OHD.