Association of lower urinary tract symptoms and hip fracture in adults aged ≥ 50 years

Abstract

Aim: Lower urinary tract symptoms (LUTS) result in morbidities; however, their association with the occurrence of hip fracture is relatively unknown in the context of Asian studies. The purpose of the study was to investigate this link with the hip fracture risk in Taiwanese men and women aged 50 years and above.

Materials and methods: From 2000 through 2012, a population-based retrospective cohort study was conducted; claims data of 18,976 patients diagnosed with LUTS (dysuria, urinary retention, incontinence, and increased urinary frequency and urgency) were retrieved from Taiwan's National Health Insurance Research Database. The patients were compared with 1:2 age, sex, and index year-matched controls (comparison group, n = 37,952). The incidence and hazard ratios of the hip fracture risk were calculated by the Cox proportional hazard regression models.

Results: The mean age was 66.2 ± 9.7 years, and the proportion of men was 58.1% in both study groups. Fractures occurred in 772 patients and 1,156 control subjects. The corresponding incidences were 7.0 and 5.0/1000 person-years. Compared to the control subjects, the patients with LUTS had an increased hip fracture risk [adjusted hazard ratio (aHR) = 1.29; 95% confidence interval (CI): 1.17-1.42]. LUTS was independently associated with an increased hip fracture risk in both men (aHR = 1.24; 95% CI: 1.08-1.42) and women (aHR = 1.34; 95% CI: 1.18-1.53) (p for interaction = 0.557). Similarly, the subgroup effect of age on hip fracture risks was not found (p for interaction = 0.665).

Conclusion: The study found LUTS was associated with an increased risk of hip fracture. Large-scale prospective studies in diverse populations are required to investigate causalities.

Fig 1. Study flow chart.

Fig 2. Cumulative incidence curves with 95% confidence intervals (colored zone) of hip fracture in LUTS patients and the comparison group.