Objective: To evaluate the prevalence of nocturia and its effects, with and without concomitant overactive bladder (OAB, i.e. urgency, frequency, urge incontinence and nocturia), on health-related quality of life (HRQoL) and sleep.
Subjects and methods: A national survey was conducted in the USA to assess the prevalence of OAB and nocturia. A nested case-control study was conducted among respondents with OAB symptoms and age- and gender-matched controls, with participants completing a series of questionnaires on HRQoL (OAB-q, Short Form-36, and Medical Outcomes Study (MOS) sleep scale). Descriptive analyses, t-tests, analysis of variance with post hoc comparisons and multivariate regressions were used to analyse the data.
Results: In all, 5204 people participated in the survey, with 919 in the nested case-control study. The sample population had a mean age of 45.8 years, was 52.6% female and 80% Caucasian. In the community sample, 31% reported > 1 void/night and 14.2% reported > 2 voids/night. The prevalence of nocturia increased with age, with no gender differences. For OAB cases, 66.8% reported > 1 void/night and 42.2% reported > 2. In the case-control cohort there were significant HRQoL differences (P < 0.01), with increasing episodes of nocturia in all OAB-q subscales except social interaction. The amount of sleep per night was significantly correlated with the sleep, concern and social interaction OABq subscale scores. The number of nocturia episodes/night was also significantly (P = 0.02) associated with the number of hours of sleep/night.
Conclusion: Nocturia is widely prevalent and increases with age, affecting men and women equally. Incremental increases in the number of voids/night have further negative effects on sleep, symptom bother, and HRQoL.