Effect of vitamin D supplementation on benign paroxysmal positional vertigo recurrence: a meta-analysis.

Benign paroxysmal positional vertigo is characterized by recurrence, which exposes patients to repeated vertigo attacks. Vitamin D deficiency has been found to be a risk factor in benign paroxysmal positional vertigo, although effect of its elimination on recurrence reduction remains unknown. To determine the effect of vitamin D supplementation in preventing recurrence of benign paroxysmal positional vertigo patients with vitamin D deficiency using a meta-analysis study. We searched and retrieved relevant articles from several databases, then used the Cochrane evaluation system or Methodological Index for Non-Randomized Studies (MINORS) to assess the quality of studies. We adopted risk-ratio (RR) with corresponding 95% confidence interval (CI) to determine effect sizes, and further performed statistical analyses under a randomized-or fixed-effects model. Seven studies, comprising 602 and 731 participants in the case and control group respectively, met our inclusion criteria, and were therefore included in the meta-analysis. Assessment based on Cochrane evaluation system or...