Abstract
OBJECTIVE: Nocturnal enuresis (NE), also known as bedwetting, is a common urological condition in children that often requires extended treatment. Although numerous studies have examined NE risk factors, the long-term effects of combined clinical and external factors, such as weather variables, remain unexplored. This study aimed to explore composite risk factors for NE and evaluate their long-term effects. METHODS: This was a prospective observational study with unbalanced panel data analyzed using the classification and regression trees (CART) model. The study was conducted in Japan, with clinical and meteorological data collected over 14 months. Nineteen pediatric patients aged 6-15 years diagnosed with NE based on International Pediatric Continence Society guidelines were included. In total, 3194 daily records from 19 participants (after excluding 1 due to excessive missing values) were analyzed. The primary outcome was the presence of incontinence. Factors evaluated included demographic variables, five treatment modalities (vasopressin, solifenacin succinate, vibegron, alarm therapy, and osmotic laxatives), and six meteorological factors (daily average ambient temperature, temperature difference, precipitation, sunshine hours, atmospheric pressure, and humidity). RESULTS: Risk factor analysis incorporating meteorological variables extracted multiple factors potentially contributing to nocturia in over 60% of patients. These included a history of desmopressin treatment without vibegron, fewer than 203 treatment days, absence of alarm therapy, and specific months (January, August, November, and December). Additionally, the presence of more than 82.5 treatment days and a daily average ambient temperature below 13.45°C were contributing factors. Meteorological variables, particularly daily average ambient temperature and calendar month, were selected as composite factors for NE risk via the CART model. Notably, vibegron was proposed to be more effective in reducing NE risk compared with other treatments. CONCLUSIONS: Our findings suggest that effective long-term management of NE may require individualized treatment plans that account for clinical and weather-related variables. Among weather-related variables, consideration of seasonal and environmental factors may be especially important in managing NE.