Combination therapy with desmopressin and an anticholinergic medication for nonresponders to desmopressin for monosymptomatic nocturnal Enuresis: A randomized, double-blind, placebo-controlled trial

Objective. Desmopressin is an approved medical therapy for the treatment of mono-symptomatic primary nocturnal enuresis. In cases of limited response to desmopressin, we have added anticholinergic therapy to desmopressin (combination therapy). To evaluate this treatment strategy, we examined the efficacy of combination therapy for primary nocturnal enuresis in desmopressin- nonresponders. Methods. Only patients with primary nocturnal enuresis refractory to the maximal dosage of desmopressin were enrolled. Children with lower urinary tract symptoms or bowel dysfunction were excluded, on the basis of a 3-day, 24-hour, frequency-volume chart and elimination record. Children continued to take desmopressin and were assigned randomly, in a double-blind manner, to receive either extended- release anticholinergic medication or placebo. Patients were reassessed after 1 month of therapy, with a 1-week nocturnal record. Results. Forty-one desmopressin-nonresponders were enrolled, and 7 patients were excluded because of noncompliance. The treatment groups were equally matched with respect to age, gender, functional bladder capacity, and number of wet nights per week. After 1 month of treatment, there was a significant reduction in the mean number of wet nights in the combination therapy group, compared with the placebo group. With a generalized estimating equation approach, there was a significant 66% decrease in the risk of a wet episode, compared with the placebo group. Conclusions. This study represents the first prospective, placebo-controlled trial examining the effect of desmopressin in combination with long-acting, anticholinergic, bladder-relaxing therapy for monosymptomatic primary nocturnal enuresis.