['To characterize nocturia in men based on frequency volume chart data and symptom profiles assessed using the Core Lower Urinary Tract Symptom Score and Athens Insomnia Scale questionnaires.', 'The Core Lower Urinary Tract Symptom Score and Athens Insomnia Scale questionnaires were administered to 299 consecutive treatment naïve men with nocturia (≥one time per night). Frequency volume chart data were recorded for 2\u2009days. Correlations between nocturia and clinical characteristics including symptom scores, clinical diagnosis, Charlson Comorbidity Index, estimated glomerular filtration rate, uroflowmetry and prostate volume were analyzed.', 'Patients were divided into five groups: one time (n\u2009=\u200936), two times (n\u2009=\u200965), three times (n\u2009=\u200985), four times (n\u2009=\u200978) and five times (n\u2009=\u200934) of nocturia. Age, prevalence or severity of chronic kidney disease, hyperlipidemia, low bladder capacity, nocturnal polyuria, urgency, bladder pain and sleep disorders were significantly correlated with the severity of nocturia. The Spearman correlation analysis identified eight possible independent factors for nocturia: age, estimated glomerular filtration rate, urgency, bladder pain, sleep quality, sleepiness during the day, average voided volume and nocturnal volume divided by body weight. Logistic regression analysis showed that nocturnal volume divided by body weight was the strongest factor of nocturia, and ≥7, 9 and 9.7\u2009mL/kg were practical cut-off values of three, four and five times per night of nocturia, respectively.'] Is nocturia in men a chaotic condition dominated by nocturnal polyuria?