The effect of nocturia on sleep quality and daytime function in patients with lower urinary tract symptoms: a cross-sectional study

BACKGROUND Nocturia has been proven to have a negative impact on the quality of life and sleep quality in general elderly population. However, there are limited studies on the quantitative effect of nocturia on sleep quality and daytime dysfunction, specifically in patients with lower urinary tract symptoms. PATIENTS AND METHODS During March 1, 2015 to December 31, 2015, a total of 728 patients who visited our urology department due to voiding dysfunction and experienced nocturia at least once per night were enrolled. Three questionnaires were administered to them after obtaining their written consents. Pittsburgh Sleep Quality Index (PSQI) questionnaire, Epworth Sleepiness Scale (ESS) questionnaire, and International Prostate Symptom Score (IPSS) questionnaire were applied to evaluate their sleep quality, daytime dysfunction, and voiding problems, respectively. Statistical analysis of the impact of nocturia on sleep quality and daytime dysfunction was performed. RESULTS The mean age of patients was 61 years, with a male-to-female ratio of 2.7. The mean nocturia number was 3.03. The IPSS, PSQI, and ESS scores were 17.56, 8.35, and 8.22, respectively. The nocturia number increased with age and was significantly correlated to ESS score (daytime dysfunction) and PSQI total score (sleep quality) in overall group. Among subgroups divided by age and sex, there was a significant correlation between nocturia number and daytime dysfunction in male patients or patients younger than 65 years. CONCLUSION In patients with lower urinary tract symptoms, nocturia number increased with age and was significantly correlated with poor sleep quality. Nocturia plays an important role in patients younger than 65 years in daytime dysfunction.