Classification of nocturia by analyzing frequency volume chart and relations with international prostate symptom score in male patients with lower urinary tract symptoms in Korea

PURPOSE: To evaluate the categories of nocturia and relationships with the international prostate symptom score (IPSS) in Korean men with lower urinary tract symptoms (LUTS) accompanying nocturia. MATERIALS AND METHODS: Five hundred twenty-one male patients from five different hospitals, aged ≥18 years, were included. The 3-day frequency volume chart was used to identify nocturia. We also used the IPSS and The International Consultation on Incontinence Modular Questionnaire-Nocturia (ICIQ-N) module to verify the correlation between nocturia and quality of life. RESULTS: The distribution of nocturia events varied from 1 to 11, and 2 nocturia events were most prevalent (48.4%). Across the various numbers of nocturia events, the mean age, first sleep period, functional bladder capacity (FBC), nocturnal polyuria index (NPI), nocturia index (NI), predicted number of nightly voids, and nocturnal bladder capacity index (NBCI) were statistically different. Patients with pure nocturnal polyuria showed different night lengths, nocturnal urine volume, FBC, NPI, NI, and predicted number of nightly voids than those without nocturnal polyuria. Patients with severely reduced NBCI were prominent in the IPSS >20 group, and the degree of vexation increased with the number of nocturia events. The IPSS storage symptom score and ICIQ-N symptom score positively correlated with nocturia events. CONCLUSIONS: In Korean male LUTS patients with nocturia, mixed-type nocturia was prominent, and patients with a high IPSS had a much poorer sleep quality than those with a low IPSS.