The Impact of Nocturia on Falls and Fractures: A Systematic Review and Meta-Analysis.

PURPOSE: Although nocturia is associated with various comorbidities, its impact on falls and fractures remains unclear. We performed a systematic review and meta-analysis to evaluate the association between nocturia and falls and fractures as a prognostic and as a causal risk factor. MATERIALS AND METHODS: We searched PubMed®, Scopus®, CINAHL (Cumulative Index to Nursing and Allied Health Literature) and abstracts of major urological meetings up to December 31, 2018. We conducted random effects meta-analyses of adjusted relative risks of falls and fractures. We applied the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach to rate the quality of evidence for nocturia as a prognostic and causal factor of falls and fractures. RESULTS: Among 5,230 potential reports 9 observational longitudinal studies provided data on the association between nocturia and falls or fractures (1 for both, 4 for falls, 4 for fractures). Pooled estimates demonstrated a risk ratio of 1.20 (95% CI 1.05-1.37, I2=51.7%, annual risk difference 7.5% among the elderly) for association between nocturia and falls and 1.32 (95% CI 0.99-1.76, I2=57.5%, annual risk difference 1.2%) for association between nocturia and fractures. Subgroup analyses showed no significant effect modification by age, gender, followup time, nocturia case definition or risk of bias. We rated the quality of evidence for nocturia as a prognostic factor as moderate for falls and low for fractures, and as very low as a cause of falls/fractures. CONCLUSIONS: Nocturia is probably associated with an approximately 1.2-fold increased risk of falls and possibly an approximately 1.3-fold increased risk of fractures.