New aspects of the classification of nocturia.

Nocturia, one of the most bothersome urologic symptoms, has been poorly classified and understood. Multiple factors may cause nocturia, such as behavioral or environmental factors and pathologic conditions, including cardiovascular disease, diabetes mellitus, lower urinary tract obstruction, anxiety or primary sleep disorders, and sleep apnea. Nocturia caused by any combination of these and other conditions may be attributed to nocturnal polyuria, diminished nocturnal or global bladder capacity, global 24-hour polyuria, or a combination of these factors. Distinction among these classes of nocturia is made by a simple arithmetic analysis of the 24-hour voiding diary. Nocturia has been poorly studied and only recently classified according to its etiology and pathogenesis. After reviewing the current state of knowledge, we present a scheme for rational diagnosis of patients suffering from loss of sleep due to nocturnal micturition. This article reviews the current state of knowledge and presents algorithms for the diagnosis and classification of nocturia.