Seasonal Changes in Lower Urinary Tract Symptoms in Japanese Men With Benign Prostatic Hyperplasia Treated With α(1)-Blockers

PURPOSE: To investigate whether seasonal changes occurred in lower urinary tract symptoms (LUTS) in patients with benign prostatic hyperplasia (BPH). METHODS: Patients aged 50 years and older with BPH treated with α(1)-blockers were enrolled. The International Prostate Symptom Score (IPSS), quality of life (QoL) score, maximum and average flow rate, voided volume, and postvoid residual volume were measured in summer and winter. RESULTS: A total of 164 patients were enrolled. The total IPSS and QoL index did not show a significant difference between the 2 seasons. When the IPSS was divided into storage symptoms and voiding symptoms, storage symptoms in winter were substantially but nonsignificantly higher than those in summer (P=0.056). Of the 7 individual symptoms in the IPSS, a significant seasonal difference was observed only for nocturia, with a higher score in winter. Moreover, none of the uroflowmetric parameters showed a seasonal change. Voided volume had significant correlations with each symptom (urgency and nocturia) and overall subjective scores (storage, total IPSS, and QoL) exclusively in summer, while this correlation remained only for nocturia in winter. CONCLUSIONS: As it has generally been assumed that LUTS deteriorate in winter, the present study corroborated that the severity of storage symptoms was higher in winter than in summer, even in patients treated with α(1)-blockers. In contrast, a seasonal difference was not observed in the uroflowmetric parameters, which may be partly due to the loss of the correlation between subjective and objective measurements of storage symptoms in winter.