Nocturia ≥ 3/Night and 5‐Year Fragility Fracture Risk in Older Urology Outpatients
Kunihisa Nezu, Maiko Yamashita, Shingo Myoen, Naoki KawamoritaABSTRACT
Aim
To evaluate whether nocturia ≥ 3/night stratifies 5‐year fragility‐fracture risk in older urology outpatients and to explore its prognostic performance alongside the N‐QoL and IPSS.
Methods
We conducted a retrospective cohort study of urology outpatients aged ≥ 65 years at Hachinohe City Hospital, Japan, between 2015 and 2024. After exclusion of patients with prior fragility fracture, bone metastasis, or pathological fracture, and application of a 3‐month landmark, 2290 participants were included. The primary outcome was first non‐pathological fragility fracture. Bone metastasis and death were treated as competing events. Fine–Gray subdistribution hazard models were adjusted for age, sex, hypertension, and diabetes. To complement effect estimates, standardized 5‐year cumulative incidence was estimated using model‐based standardization.
Results
Over a median follow‐up of 48.1 months, 98 fragility fractures occurred; 42 bone metastases and 18 deaths were treated as competing events. Nocturia ≥ 3/night was associated with higher fracture risk than nocturia < 3/night (subdistribution hazard ratio [sHR] 2.11, 95% confidence interval [CI] 1.41–3.17). Impaired N‐QoL was also associated with higher risk (sHR 1.92, 95% CI 1.12–3.30), whereas severe IPSS showed a weaker association (sHR 1.79, 95% CI 1.00–3.22). The standardized 5‐year fracture risk was 9.8% for nocturia ≥ 3/night and 4.8% for nocturia < 3/night, corresponding to an absolute difference of 5.0 percentage points.
Conclusions
Nocturia ≥ 3/night was associated with higher 5‐year fragility‐fracture risk and may prompt consideration of falls and bone‐health assessment in older urology outpatients.