Abstract
OBJECTIVES: To investigate the prevalence, impact on health-related quality of life (HRQOL), and predictive factors of co-existent overactive-underactive bladder (COUB) in women. METHODS: 3088 Japanese women aged ≥ 20 years responding to a nationwide internet survey on lower urinary tract symptoms (LUTS) were included. Participants were divided into COUB, overactive bladder (OAB) alone, underactive bladder (UAB) alone, and non-OAB/UAB groups based on the OAB symptom score and the International Continence Society-Working Group definition of UAB. In addition to the prevalence, we assessed each group's HRQOL and physician visit rates. We further explored predictors of COUB as well as OAB and UAB using multinomial logistic regression analysis. RESULTS: The prevalences of COUB, OAB alone, and UAB alone were 1.6%, 8.2%, and 2.4%, respectively, and all increased significantly with age. The proportions of COUB in OAB and UAB overall were 16.4% and 40.7%, respectively. The proportions of participants who responded that their HRQOL was affected and those visiting physicians were both highest in the COUB group. Multinomial logistic regression analysis showed that age, frailty, neurological disorders, anorectal dysfunction, pelvic organ prolapse, and parity (≥ 3) were independent predictors for COUB, of which age, neurological disorders, and parity were exclusively associated with COUB. CONCLUSIONS: Although not highly prevalent, COUB may have a significant impact on adult women, especially frail and multimorbid elderly women. More attention should be paid to this unique condition for optimal LUTS management.