Associations of vitamin D receptor activators and calcimimetics with falls and effect modifications by physical activity: A prospective cohort study on the Japan Dialysis Outcomes and Practice Patterns Study

Introduction This study aimed to examine the associations of vitamin D receptor activators (VDRA) and calcimimetics use with falls. Methods This is a prospective cohort study on hemodialysis patients in the Japan Dialysis Outcomes and Practice Patterns Study. We excluded those who were unable to walk. The associations of VDRA or calcimimetics use with falls and effect modifications by physical activity were analyzed using marginal structural models. Results In total, 1875 patients were included. VDRA and calcimimetics use was not associated with falls (risk ratio [95% CI]: 1.13 [0.84-1.51] and 1.02 [0.72-1.44]). The risk ratio for falls associated with VDRA use was lower among those with poor physical activity (p for interaction <0.1). Conclusions Although vitamin D receptor activators and calcimimetics use was not associated with falls, the lower risk ratio for falls with vitamin D receptor activators use among those with poor physical activity suggests that vitamin D receptor activators use might be beneficial among these patients.