Alarms for Nocturnal Bed-Wetters Help Keep Children Dry

EDMONTON, Alberta, June 9 - Enuresis alarms proved safe and reasonably effective for helping children keep a dry bed, according to an "umbrella" review of several hundred trials.

Among pharmacological interventions, the hormone desmopressin took second place for safely improving night-time continence in children ages five to 16. These results came from an analysis of seven systematic reviews of 230 trials reported in the first issue of the newly launched Evidence-Based Child Health: A Cochrane Review Journal.

However, all therapies for children with this distressing problem had disadvantages and limitations, according to Cochrane review authors Kelly Russell, project coordinator of the Evidence Based Practice Center, and Darcie Kiddoo, M.D., both at the University of Alberta here.

Alarm therapy to awaken the sleeping child (as well as the rest of the family) as urine starts to leak proved most effective and, unlike drug therapy, the benefits were likely to last after treatment stopped, the researchers said. Once activated by micturition, the alarm sounds, the child is supposed to awaken, inhibit urination, and use the toilet to complete voiding.

In a database search of seven randomized or quasi-randomized reviews that included studies of any treatment for nocturnal enuresis, the researchers synthesized the results for the following treatments: behavioral therapy, bed-alarm therapy, desmopressin treatment, and pharmacologic therapy with tricyclics or drugs such as Indocin (indomethacin), Voltaren (diclofenac), and Valium (diazepam). Complementary treatments such as hypnosis were also included in the review.

The methodological quality of the included studies was "generally poor," Russell and Dr. Kiddoo said.

The findings were as follows:

• Enuresis alarms were the most successful. When compared with placebo or no treatment, the alarms resulted in approximately three more dry nights a week (WMD -3.34 [95% CI -4.14, -2.55]), and the relative risk for not achieving 14 consecutive dry nights was significantly less among the alarm-treated children (RR 0.38 [CI 0.33, 0.45]).

• The difference was maintained when children were assessed at follow-up, but sufficient evidence precluded a comparison of alarms to behavioral therapy or drug treatment.

• Desmopressin is a hormone that induces an anti-diuretic effect with the subsequent risk of water intoxication. But at any dose compared with placebo, desmopressin resulted in more dry nights, although the optimal dose or route of delivery could not be established.

However, there was no evidence to suggest that the effectiveness of desmopressin lasts once treatment is completed, and the effect of adding an alarm to desmopressin remains unclear. Also, there was not enough evidence to compare desmopressin with behavioral methods.

• Tricyclics compared with placebo eliminated one wet night a week (WMD -1.19 [CI -1.56, -0.82]). However, the benefits did not last beyond treatment, and the most effective drug and dose could not be determined. Alarms, however, were found superior in one study both during and after treatment, while results for tricyclics versus desmopressin were conflicting.

• Placebo trials were limited for Indocin, Voltaren, and Valium although in the few trials available, these drugs outdid placebo.* Simple behavioral therapy (such as reward systems for dry nights, lifting, and waking) proved helpful but could not be evaluated because of limited evidence. However, these interventions appear to be safe, although labor intensive.

• Complex behavior interventions (dry-bed training in which the child is awakened every hour, clean-up training, and repeated practice getting up and going to the toilet) did not appear to be any better than no treatment. However, when combined with an alarm there were significantly fewer failures compared with no treatment.

• Among complementary and other interventions, hypnosis and psychotherapy appeared to help. However, there were too few studies to determine the appropriateness of these interventions or diet and food restriction.

Summarizing the results, Russell and Dr. Kiddoo wrote that in practice the alarm was most successful. However, if the child does not wake up while the rest of the house does, family members may decide that the intervention has failed. The treatment should not be abandoned, the researchers advised, because if properly instructed, families can work together to help the child respond.

Desmopressin also improved nocturnal continence, suggesting that only those children with polyuria would benefit from the medication, they said. For this reason, some centers record nightly output prior to beginning treatment with desmopressin in order to predict failure.

The tricyclics, while useful in some patients, are potent medications and are losing favor with most physicians. "Concern over the potential for overdose and the less promising results as seen in this umbrella review make these medications undesirable," Russell and Dr. Kiddoo wrote.

The evidence for the other drugs looks promising, but again, like the tricyclics, these medications are not benign. Bed alarms and desmopressin are safer treatments, they said.

Behavioral treatments, such as rewarding the child for dry nights, are well tolerated and help improve the child's self-image. Unfortunately, the researchers wrote, lack of evidence makes it difficult to support these time-intensive measures. Still, many parents start out with them, seeking help only if they fail.

While the etiologies remain speculative for the cause of bed-wetting, the researchers wrote, newer studies of nocturnal bladder physiology point to a complex interaction between the urinary tract and the nervous system. A certain percentage of children go undiagnosed who actually have daytime symptoms but don't present because of frequent voiding. It is therefore unlikely, they concluded, that one treatment will be helpful for all children.