Background: Neurogenic bladder affects up to 80% of patients with multiple sclerosis (MS) and, in 50% of these patients, it is a significant cause of disability. The current management of neurogenic bladder, based on fluid restriction, anticholinergic agents, intermittent self-catheterization, and, in some cases, surgical intervention, often fails to relieve all symptoms. Furthermore, anticholinergic drugs have significant adverse effects and may be medically contraindicated. Nocturia is a particularly disabling symptom of neurogenic bladder; by disrupting sleep patterns, it aggravates the chronic fatigue of MS, imposes serious demands on caregivers, and can lead to institutionalization. To evaluate a novel approach to the symptomatic management of nocturia in patients with MS, we have conducted a trial of desmopressin acetate (1-desamino-8-D-arginine vasopressin), a synthetic analogue of antidiuretic hormone.
Objective: To evaluate the efficacy and short-term safety of desmopressin therapy in the symptomatic treatment of nocturia in patients with MS.
Methods: Seventeen patients were enrolled in a double-blind, crossover trial of desmopressin administered at bedtime. Patients with both relapsing-remitting and chronic-progressive forms of MS were admitted. Night time voiding diaries were maintained for the 6 weeks of the trial; similarly, serum electrolyte levels and plasma osmolality were measured twice weekly and urinalyses and urine cultures were performed weekly during the trial.
Results: Desmopressin reduced the percentage of nights with nocturia in patients from 97% to 66%. The average number of episodes of nocturia per night in patients decreased from 2.35 to 1.09 and the maximum hours of sleep uninterrupted by nocturia increased from 3.74 to 5.77. These results were highly significant. Four of the 17 patients discontinued participation in the study after developing asymptomatic or minimally symptomatic hyponatremia.
Conclusions: Desmopressin was found effective; no tolerance and only minimal adverse effects have been observed. Our results suggest that desmopressin, either alone or in combination with other therapeutic modalities, is effective in the symptomatic management of nocturia in patients with MS. The only adverse effect attributed to desmopressin was hyponatremia, which occurred in 4 of 17 patients and appeared to be dose related.