Sleep and quality of life in nocturia and nocturnal polyuria

Abstract

Nocturia, waking up at night to void, is a highly prevalent disorder in the elderly, with a profound impact on life expectancy, health, and quality of life (QoL). Elderly persons with nocturia are troubled by sleep impairment because of involuntary awakenings, increased nightmares, and a general feeling of insufficient and non-restorative sleep. Consequently, their daytime performance is impaired and they are more inclined to daytime sleepiness and napping than the elderly in general. Particularly, waking up three or more times a night to void is related to a steep increase in sleep disturbances. Giddiness both at night and during the daytime is another common consequence, since in three cases of four nocturia is due to nocturnal urine overproduction, causing a negative fluid balance. Nocturia may be attributable to nocturnal polyuria (nocturnal urine overproduction), a diminished nocturnal bladder capacity, or a combination of the two. In some elderly people, a disorder of the vasopressin system, with very low or undetectable levels of vasopressin at night and in some cases throughout the entire 24-h period may cause an increase in nocturnal urine output, which in most extreme cases will account for 85% of the 24-h diuresis. The increased urine output can be treated with desmopressin orally at bedtime, in generally low doses. Nocturia is also more prevalent in association with reduced bladder capacity. Antimuscarinic drugs may be administered to depress involuntary bladder contractions. This chapter emphasizes the importance of correctly diagnosing and treating nocturia in order to improve the patients' sleep and, in turn, to reduce the risk of fall injuries and their detrimental consequences and to improve health and QoL. © 2008 Humana Press, Totowa, NJ.