Nocturia as a clinical marker of loss of function and resilience or risk factor for frailty in older adults? Results of the Berlin Aging Study II.

The current study examined cross-sectional and longitudinal associations between nocturia and frailty in a cohort of men and women aged 60 years and older, as evidence on this topic was lacking. We analyzed baseline and follow-up data (n = 1671) from the Berlin Aging Study II (BASE-II), a prospective longitudinal cohort study focusing on the factors associated with "healthy" vs. "unhealthy" aging. Self-reported nocturia was dichotomized into < / ≥ 2 micturitions per night, and frailty was assessed using the Fried frailty phenotype. Covariables were identified a priori based on a review of the existing literature. At baseline, 70.2% of the participants were robust, 28.9% were pre-frail, and 0.9% were frail; 254 participants (23.6%) had self-reported nocturia. In longitudinal analyses, the prevalence and incidence of frailty at follow-up significantly increased when nocturia was present at baseline. Over a median follow-up of 7.1 years, there were 41 incident frailty cases (IR 5.6, 95%-CI 3.9-7.2 per 1000 person-years). After adjusting for age, sex, morbidity burden, and baseline frailty status, baseline nocturia was associated with a 2.23-fold increased risk (95%-CI 1.17-4.18) of frailty at follow-up. Nocturia is associated with an increased risk of developing or progressing in frailty in older adults, and may serve as an early clinical marker for the progression of frailty.