Desmopressin for nocturnal enuresis in children.

BACKGROUND: Enuresis (bedwetting) is a socially disruptive and stressful condition which affects around 15-20% of five year olds, and up to 2% of young adults. Although there is a high rate of spontaneous remission, the social, emotional and psychological costs to the children can be great.

OBJECTIVES: To assess the effects of desmopressin on nocturnal enuresis in children, and to compare desmopressin with other interventions.

SEARCH STRATEGY: The following electronic databases were searched: MEDLINE to June 1997; AMED; ASSIA; BIDS; BIOSIS Previews (1985-1996); CINAHL; DHSS Data; EMBASE (1974 to June 1997); PsycLIT and SIGLE. Organisations, manufacturers, researchers and health professionals concerned with enuresis were contacted for information. The reference sections of obtained studies were also checked for further trials. Date of the most recent search: July 1997.

SELECTION CRITERIA: All randomised trials of desmopressin for nocturnal enuresis in children were included in the review. Trials were eligible for inclusion if: children were randomised to receive desmopressin compared with placebo, other drugs or other conservative interventions for nocturnal bedwetting; participants with organic causes for their bedwetting were excluded; and baseline assessments of the level of bedwetting were reported. Trials focused solely on daytime wetting were excluded.

DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed the quality of the eligible trials, and extracted data.

MAIN RESULTS: Twenty one randomised trials involving 948 children treated with desmopressin, met the inclusion criteria. The quality of many of the trials was poor. Desmopressin was compared with a tricyclic drug in two trials, and with alarms in one. Desmopressin was effective in reducing bedwetting in a variety of doses and forms. Each dose of desmopressin reduced bedwetting by at least one night per week during treatment (eg 20microg: 1.56 fewer wet nights per week, 95% CI -1.94 to -1.19). Participants on desmopressin were 4.6 times more likely to achieve 14 consecutive dry nights (95% CI 1.38 to 15.02) compared with placebo. However, there was no difference after treatment was finished. There was no apparent dose-related effect of desmopressin, but the evidence was limited. Data which compared oral and nasal administration were too few to be conclusive. Desmopressin and imipramine (a tricyclic drug) were equally effective in one small trial. Amitriptyline (another tricyclic) was not consistently better than desmopressin either alone or when used as a supplement. In a single trial, desmopressin was initially superior to using an alarm in reducing the number of wet nights per week: WMD -1.7 (95% CI: -2.96 to -0.45), but this result was not sustained; after three months of treatment, patients using the alarm had 1.4 fewer wet nights per week than with desmopressin: (95% CI: 0.14 to 2.65). Participants receiving the alarm intervention were also nine times less likely to relapse than those given desmopressin: RR 9.2 (95% CI: 1.28 to 65.9). Combining alarm and drug therapy was found to be superior to alarm treatment alone. The addition of desmopressin to an alarm schedule resulted in one less wet night per week: (95% CI: -1.55 to -0.45).

REVIEWER'S CONCLUSIONS: Desmopressin rapidly reduced the number of wet nights per week, but there was some evidence that this was not sustained after treatment stopped. Comparison with alternative treatments suggested that desmopressin and tricyclics had similar clinical effects, but that alarms produced more sustained benefits. However, based on the available evidence, these conclusions can only be tentative. There was some evidence of minor side effects of desmopressin in the included trials, such as nasal irritation and nose bleeds. However, the risk of water intoxication associated with over-drinking before bedtime has been reported. Patients and their families need to be warned of potential adverse effects and advise