Risk factors for benign paroxysmal positional vertigo recurrence: a systematic review and meta-analysis

Benign paroxysmal positional vertigo is one of the most common vestibular diseases, especially in the elderly. Although the treatment of BPPV is relatively successful, many patients suffer recurrence after treatment. Therefore, identifying potential risk factors for BPPV recurrence may help improve treatment outcome and patient prognosis. However, some related risk factors for BPPV recurrence are relatively controversial and poorly studied. This meta-analysis aims to identify potential risk factors associated with BPPV recurrence, thereby reducing the recurrence rate of BPPV and improving the prognosis of patients.

This meta-analysis was conducted through systematically searching PubMed, Embase, and the Cochrane Library for eligible English original studies published up to June 2020. All search results were reviewed based on our inclusion and exclusion criteria. We calculated the pooled odds ratios (ORs) or the mean differences (MDs) with their corresponding 95% confidence intervals (CIs) to evaluate the effects of included risk factors on BPPV recurrence.

A total of 14 studies involving 3060 BPPV patients published between 2010 and 2019 were finally included, including six prospective studies and eight retrospective studies, with a NOS score ranged from 6 to 9. Our pooled results of this meta-analysis suggested that the recurrence of BPPV was closely related to female gender (OR = 1.42; 95% CI 1.17-1.74; P = 0.0004), hypertension (OR = 2.61; 95% CI 1.22-5.59; P = 0.01), diabetes mellitus (OR = 2.62; 95% CI 1.25-5.48; P = 0.01), hyperlipidemia (OR = 1.60; 95% CI 1.23-2.09; P = 0.0006), osteoporosis (OR = 1.72; 95% CI 1.03-2.88; P = 0.04) and vitamin D deficiency (MD = - 3.29; 95% CI - 5.32 to - 1.26; P = 0.001).

This meta-analysis indicated that female gender, hypertension, diabetes mellitus, hyperlipidemia, osteoporosis, and vitamin D deficiency were risk factors for BPPV recurrence. However, the effects of other potential risk factors including advanced age, migraine, head trauma, and Menière's disease on BPPV recurrence need further investigations. Furthermore, most studies included in this meta-analysis were performed in Asia, so our results cannot easily be extended to the whole world population. Therefore, more large-scale prospective studies in different countries are required to further investigate these risk factors.