[Impact of body mass index on lower urinary tract disorders in multiple sclerosis]

Introduction: Lower urinary tract symptoms (LUTS), and principally overactive bladder, are common in multiple sclerosis (MS). However, their origin is not necessarily unique. Obesity is widely recognized as a risk factor for stress urinary incontinence (SUI) and overactive bladder (OAB) in the general population. We wanted to evaluate the influence of body mass index (BMI) on LUTS in the MS population.

Materials and methods: We conducted an uncontrolled monocentric retrospective study in 260 subjects classified into 4 BMI groups: underweight, normal weight, overweight, obese people. Comparisons by Mann-Whitney test were made between different BMI groups, in the overall population and then by gender. LUTS (SUI, OAB, BOO (bladder outlet obstruction) were assessed using USP questionnaire.

Results: In women, the mean OAB score was higher for obese women, 10.27 (SD=4.5) than for normal weight women, 7.96 (SD=4.58), P=0.024. The SUI score was lower for normal weight, 1.69 (SD=2.38) than for overweight, 3.19 (SD=2.91), P=0.002 and obese subjects, 3.80 (SD=3.23), P=0.0005. As in the overall population, the BOO score was higher in subjects with normal weight, 4.09 (SD=3.33) than in subjects with overweight, 1.91 (SD=2.03), P=0.0003 and in obese subjects, 2.33 (SD=2.37), P=0.013. The same comparisons in men were not significant.

Conclusion: In this series, increased BMI was associated with higher OAB and SUI USP questionnaire scores, in women presenting with MS.

Level of evidence: 4.