Effect of monthly vitamin D on diverticular disease hospitalization: Post-hoc analysis of a randomized controlled trial

Summary Background & aims Some studies have linked low vitamin D status and high risk of diverticular disease, but the causal relationship between vitamin D and diverticular disease remains unclear; clinical trial data are warranted. The objective was to assess the efficacy of vitamin D3 supplementation on diverticular disease hospitalization. Methods Post-hoc analysis of a community-based randomized double-blind placebo-controlled trial (RCT) with 5108 participants randomized to receive monthly 100,000 IU vitamin D (n=2558) or identical placebo (n=2550). The outcome was time to first diverticular disease hospitalization from randomization to the end of intervention (July 2015), including a prespecified subgroup analysis in participants with baseline deseasonalized 25-hydroxyvitamin D (25(OH)D) levels Results Over a median of 3.3 years follow-up, 74 participants had diverticular disease hospitalization. There was no difference in the risk of diverticular disease hospitalization between vitamin D supplementation (35/2558=1.4%) and placebo (39/2550=1.5%) groups (adjusted hazard ratio [HR]=0.90; p=0.65), although in participants with deseasonalized 25(OH)D Discussion Monthly 100,000 IU vitamin D3 does not reduce the risk of diverticular disease hospitalization in the general population. Further RCTs are required to investigate the effect of vitamin D supplementation on the diverticular disease in participants with low 25(OH)D levels.