Background:
Bedwetting (nocturnal enuresis or enuresis) is the involuntary loss of urine during sleep without being caused by a physical disorder. It can result in social, emotional and psychological problems and lower quality of life. It affects around 15% to 20% of five-year-olds, and can persist in up to 2% of adults. Many different types of drugs have been used to treat bedwetting, both as a single treatment and in combination with other treatments. Tricyclics are antidepressants, which have been used for treating bedwetting since the 1960s. They probably work by their antispasmodic effect on the bladder. This review examines 64 trials of tricyclic drugs, involving 4071 children.
Main findings:
The most commonly used tricyclic for treating bedwetting is imipramine. Compared to placebo, tricyclics reduce bedwetting by about one night per week during treatment and about a fifth of the children achieve 14 dry nights. However, most wet again once the tricyclics are stopped.
Adverse effects:
Tricyclics are just as effective as the other commonly-used drug, desmopressin. However, they have more side effects, such as seizures, effects on the heart, liver and blood including low white cell counts, particularly if overdosed, which can be serious. The available evidence suggests that bedwetting alarms are a more effective treatment for bedwetting than tricyclics, and do not have the side effects. They also have a more sustained effect after stopping, but they require more effort by the child and more support by their families to be effective.
Limitations:
Most of the studies included in the review are old (latest 2008), small and of low quality, with insufficient information to judge the risk of bias. The evidence in this review is current up to 30 November 2015.
There was evidence that tricyclics are effective at reducing the number of wet nights during treatment, but do not have a sustained effect after treatment stops, with most children relapsing. In contrast, there was evidence that alarm therapy has better short- and long-term outcomes. There was some evidence that tricyclics combined with anticholinergics may be more effective that tricyclic monotherapy.
Enuresis (bedwetting) affects up to 20% of five year-olds and 2% of adults. Although spontaneous remission often occurs, the social, emotional and psychological costs can be great. Tricyclics have been used to treat enuresis since the 1960s.
To assess the effects of tricyclic and related drugs compared with other interventions for treating children with enuresis.
We searched the Cochrane Incontinence Group Specialised Trials Register (containing trials identified from the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, MEDLINE in process, ClinicalTrials.gov, WHO ICTRP and handsearching of journals and conference proceedings), on 30 November 2015, and reference lists of relevant articles.
We included all randomised and quasi-randomised trials comparing a tricyclic or related drug with another intervention for treating enuresis. We also included combination therapies that included tricyclics. We excluded trials for treating daytime wetting.
Two review authors independently assessed the quality of the eligible trials, and extracted data. We settled differences by discussion with a third review author.
Sixty-four trials met the inclusion criteria, involving 4071 children. The quality of many trials was poor, with comparisons addressed by single studies. Minor adverse effects were common, and reported in 30 trials. These included dizziness, headache, mood changes, gastrointestinal discomforts and neutropenia. More serious side-effects can occur but were not reported. Seven trials reported no adverse effects.
Tricyclics are more effective than placebo, particularly for short-term outcomes. Compared to placebo, imipramine resulted in one fewer wet nights per week (mean difference (MD) -0.95, 95% confidence interval (CI) -1.40 to -0.50; 4 trials, 347 children), with fewer failing to achieve 14 consecutive dry nights (78% versus 95% for placebo, RR 0.74, 95% CI 0.61 to 0.90; 12 trials, 831 children). Amitriptyline and desipramine were more effective than placebo, but nortriptyline and mianserin showed no difference. Most tricyclics did not have a sustained effect after ceasing treatment, with 96% wetting at follow-up for imipramine versus 97% for placebo.
Imipramine combined with oxybutynin is also more effective than placebo, with 33% failing to achieve 14 consecutive dry nights at the end of treatment versus 78% for placebo (RR 0.43, 95% CI 0.23 to 0.78; 1 trial, 47 children) and 45% wetting at follow-up versus 79% for placebo (RR 0.58, 95% CI 0.34 to 0.99; 1 trial, 36 children).
There was insufficient evidence to judge the effect between different doses of tricyclics, and between different tricyclics. Treatment outcomes between tricyclic and desmopressin were similar, but were mixed when tricyclic was compared with an anticholinergic. However, when imipramine was compared with desmopressin plus oxybutynin (1 trial, 45 children), the combination therapy was more effective, with one fewer wet nights per week (MD 1.07, 95% CI 0.06 to 2.08) and 36% failing to achieve 14 consecutive dry nights versus 87% for imipramine (RR 2.39, 95% CI 1.35 to 4.25). Tricyclics were also more effective or showed no difference in response when compared to other drugs which are no longer used for enuresis.
Tricyclics were less effective than alarms. Although there was no difference in the number of wet nights, 67% failed to achieve 14 consecutive dry nights for imipramine versus only 17% for alarms (RR 4.00, 95% CI 1.06 to 15.08; 1 trial, 24 children). Alarm therapy also had a more sustained effect after ceasing treatment with 100% on imipramine versus 58% on alarms wetting at follow-up (RR 1.67, 95% CI 1.03 to 2.69; 1 trial, 24 children).
Imipramine was more effective than simple behavioural therapies during treatment, with one fewer wet nights per week compared with star chart plus placebo (MD -0.80, 95% CI -1.33 to -0.27; 1 trial, 250 children). At follow-up 40% were wet with imipramine versus 80% with fluids and avoiding punishment (RR 0.50, 95% CI 0.28 to 0.89; 1 trial, 40 children). However, imipramine was less effective than complex behavioural therapies, with 61% failing to achieve 14 consecutive dry nights for imipramine versus 33% for the three-step programme (RR 1.83, 95% CI 1.08 to 3.12; 1 trial, 72 children) and 16% for the three-step programme combined with motivational therapy and computer-led education (RR 3.91, 95% CI 2.30 to 6.66; 1 trial, 132 children) at the end of treatment, with similar results at follow-up.
Tricyclics were more effective than restricted diet, with 99% failing to achieve 14 consecutive dry nights versus 84% for imipramine (RR 0.84, 95% CI 0.75 to 0.93; 1 trial, 147 children).There was insufficient evidence to judge the effect of tricyclics compared to the other miscellaneous interventions studied.
At the end of treatment there were about two fewer wet nights for imipramine plus oxybutynin compared with imipramine monotherapy (MD -2.10, 95% CI -2.99 to -1.21; 1 trial, 63 children) and 48% on imipramine plus oxybutynin failed to achieve 14 consecutive dry nights compared with 74% on imipramine monotherapy (RR 0.68, 95% CI 0.50 to 0.92; 2 trials, 101 children). At follow-up, 45% on imipramine plus oxybutynin were wetting versus 83% on imipramine monotherapy (RR 0.55, 95% CI 0.32 to 0.92; 1 trial, 36 children).
When imipramine combined with desmopressin was compared with imipramine monotherapy, there was no difference in outcomes. However, when imipramine plus desmopressin was compared with desmopressin monotherapy, the combination was more effective, with 15% not achieving 14 consecutive dry nights at the end of treatment for imipramine plus desmopressin versus 40% for desmopressin monotherapy (RR 0.38, 95% CI 0.17 to 0.83; 1 trial, 86 children). Tricyclics combined with alarm therapy were not more effective than alarm monotherapy, alarm combined with desmopressin or alarm combined with nortriptyline. The addition of a tricyclic to other behavioural therapies did not alter treatment response.