Vitamin D levels and the risk of overactive bladder: a systematic review and meta-analysis

Abstract

Context: Overactive bladder is treated mainly with behavioral and drug therapy, and symptoms of urinary frequency and incontinence are challenging to eliminate. There is thus a continuous unmet need for new drugs with a substitution effect mechanism.

Objective: It not known whether vitamin D deficiency can lead to overactive bladder or urinary incontinence or whether vitamin D supplementation alleviates bladder symptoms. This comprehensive systematic review with meta-analysis was conducted to determine whether overactive bladder is associated with vitamin D deficiency.

Data sources: The PubMed and Cochrane Library databases were searched systematically up to July 3, 2022.

Data extraction: Initially, 706 articles were identified in the literature search, of which 13 were included in the systematic review: 4 randomized controlled trials, 3 cohort studies, 3 cross-sectional studies, and 3 case-control studies.

Data analysis: An increased risk of overactive bladder and urinary incontinence was observed with vitamin D deficiency (odds ratio [OR] = 4.46; 95%CI, 1.03-19.33; P = 0.046 and OR = 1.30; 95%CI, 1.01-1.66; P = 0.036, respectively). Vitamin D levels were relatively low in patients with overactive bladder or urinary incontinence (SMD = -0.33; 95%CI, -0.61 to -0.06, P = 0.019). On the basis of existing data, the risk of urinary incontinence was reduced by 66% after vitamin D supplementation (OR = 0.34; 95%CI, 0.18-0.66; P = 0.001). Egger test was conducted to assess publication bias, and the results were tested for robustness using a sensitivity analysis.

Conclusions: Vitamin D deficiency increases the risk of overactive bladder and urinary incontinence, and vitamin D supplementation reduces the risk of urinary incontinence. The development of new strategies to prevent or alleviate bladder symptoms is crucial. Vitamin D supplementation may be gaining recognition as an effective strategy for prevention or alleviation of bladder symptoms such as overactive bladder and incontinence.

Systematic review registration: PROSPERO registration no. CRD42022351443.

Keywords: meta-analysis; overactive bladder; urinary incontinence; vitamin D levels; vitamin D supplementation.