Nocturia: A Highly Prevalent Disorder With Multifaceted Consequences.

Nocturia is a bothersome, multifactorial condition with many underlying causes and contributing factors. Nocturnal polyuria (NP; overproduction of urine at night) is a frequent component. The prevalence of nocturia increases with age; specific estimates of prevalence are influenced by frequency thresholds used to define it. There is a tendency toward higher prevalence in young women than young men, which is reversed in later life. The association between frequency of nocturnal voiding and sleep disruption is well-documented. Nocturia correlates strongly with shorter sleep during the first part (2-4 hours) of the night, during which the first nocturnal void often occurs. A short time to first void after sleep onset (often referred to as "first uninterrupted sleep period") is associated with increased daytime dysfunction and decreased sleep quality and/or sleep efficiency. Adverse health consequences related to nocturia include poor sleep, depression, reduced quality of life, and increased risk of morbidity, mortality, falls, and fractures; studies have been able to establish a causal role for nocturia in only some of these. The potential impact of nocturia on health increases with age. By age 80, 80% of people will rise at least once per night to void. Despite its associated bother, nocturia is often accepted as a natural consequence of aging and many people do not seek help. Women, in particular, may be reluctant to report nocturia. This article reviews the prevalence of nocturia, possible impact on sleep, mortality and morbidity, and falls, and its importance in the elderly/frail population and women.