Among people with chronic kidney disease (CKD), vitamin D therapy does not lower all-cause mortality in comparison with placebo, according to a systematic review and meta-analysis of randomized controlled trials (RCTs). In addition, whether supplementation with the vitamin affected fracture or cardiovascular or kidney outcomes was uncertain.
“Overall, 128 studies involving 11,270 participants were included,” the authors write. “Compared with placebo, vitamin D therapy probably had no effect on all-cause death (relative risk [RR], 1.04; 95% CI, 0.84-1.24); and uncertain effects on fracture (RR, 0.68; 95% CI, 0.37-1.23) and cardiovascular death (RR, 0.73; 95% CI, 0.31-1.71). Compared with placebo, vitamin D therapy lowered serum parathyroid hormone and alkaline phosphatase, but increased serum calcium.”
Editorial: “The next chapters of the vitamin D story must move the field of [chronic kidney disease–mineral and bone disorder (CKD-MBD)] beyond a stalemate of equivocal treatment effects,” editorialists write. “[This meta-analysis] is a sobering reminder that despite more than 100 RCTs involving >10,000 participants, the kidney community has yet to decisively conclude whether one of the most ubiquitous treatments for a common complication is effective in CKD. With substantial time and money spent on CKD-MBD care worldwide, identifying optimal strategies for vitamin D use in CKD could have a large impact on morbidity, mortality, and cost.”