Nocturnal Urinary Disorders and Multiple Sclerosis: Clinical and Urodynamic Study of 309 Patients

The aim of this study was to describe nocturia with or without leakage in a population of patients with multiple sclerosis.

This is a retrospective, single center study of 309 patients with multiple sclerosis who were followed at an experienced neurourology center between 2011 and 2013. All patients had daytime urinary symptoms associated with this disorder. Among the patients with nocturia 2 groups were defined, including those with isolated nocturia but without nocturnal urinary incontinence and patients with nocturia associated with nocturnal urinary incontinence. The control group comprised patients without nocturia. The clinical variables and urodynamic data studied were gender, age, EDSS (Expanded Disability Status Scale), the USP (Urinary Symptoms Profile) questionnaire overactive bladder score, bladder capacity, detrusor activity and volume at the first detrusor contraction.

Of our patients 53.3% had nocturia, including 35.7% with nocturnal urinary incontinence. The average ± SD USP overactive bladder score was statistically greater in patients with nocturia than in controls (9.14 ± 4.3 vs 5.1 ± 3.5, p = 8.21E-17). Mean maximum cystometric capacity was statistically higher in the control group than in patients with nocturia (380.17 ± 113.79 vs 313 ± 128.4 ml, p = 5.60E-6). A similar outcome was found for the first contraction (mean 232.58 ± 146.05 vs 181.14 ± 100.11 ml, p = 0.041).

Isolated nocturia or nocturnal urinary incontinence is a frequent problem encountered with multiple sclerosis. Our results suggest that an overactive detrusor is the main mechanism. Further studies are needed to verify the complications arising from nocturia.