Does structured withdrawal of desmopressin improve relapse rates in patients with monosymptomatic enuresis?

Relapse after cessation of desmopressin is an important problem in treating patients with enuresis. Structured withdrawal of desmopressin tablets has been shown to decrease relapse rates. However, scientific data are lacking on the structured withdrawal of the fast melting oral formulation of desmopressin. We compared relapse rates of structured withdrawal using placebo and direct cessation in a population of patients with enuresis who were desmopressin responders.

Patients diagnosed with enuresis and responding to desmopressin from 13 different centers were involved in the study. Patients were randomized into 4 groups. Two different structured withdrawal strategies were compared to placebo and direct withdrawal. Sample size was estimated as 240 (60 patients in each group), with a power of 0.80 and an effect size of 30%. Randomization was performed using NCSS statistical software (NCSS, Kaysville, Utah) from a single center. The relapse rates of the groups were compared using chi-square testing. Logistic regression analysis was performed to define the independent factors having an effect on relapse rates.

Desmopressin treatment was initiated in 421 patients, and 259 patients were eligible for randomization. Relapse rates were 39 (1%) and 42 (4%) for the structured withdrawal groups, which were significantly less than for direct withdrawal (55, 3%) and placebo (53, 1%). Logistic regression analysis revealed that initial effective dose of 240 μcg, greater number of wet nights before treatment and nonstructured withdrawal were associated with higher relapse rates.

We found that structured withdrawal with the fast melting oral formulation of desmopressin results in decreased relapse rates. Application of a structured withdrawal program was also an independent factor associated with reduced relapse rates, together with lower initial effective dose and number of wet nights per week. Relapse after cessation of desmopressin is an important problem, and in this study structured withdrawal was observed to be associated with decreased relapse rates compared to placebo and direct withdrawal.