An observational prospective study that was conducted in accordance with the principles established by the 18th World Medical Assembly Helsinki (1964) [8], International Council for Harmonization guidelines for good clinical practice, and in compliance with all national and international laws and regulations. Written informed consent was obtained from all participants in this study.
Five hundred patients attending Kasr Al-Ainy MS Clinic, Neurology Department, Cairo University Hospitals, Egypt, from December 2016 to March 2018, were evaluated for MS diagnosis and the presence of bladder dysfunction symptoms. Clinically definite multiple sclerosis (CDMS) according to the revised McDonald criteria (2010) [9] was verified in subjects; 228 of them had voiding dysfunction during their disease course. Eventually, 120 eligible subjects accepted to sign the informed consent (Fig. 1). Patients with other diagnoses such as history of diabetes mellitus, bladder neck surgery, prostate enlargement and fracture spine, and urinary tract infection at time of assessment were excluded.
Full history and neurological examination were carried out via a specialized neurologist, with assessment of disease severity using Expanded Disability Status Scale (EDSS) [10] at baseline and at the end of 1-year follow-up. A careful analysis of urological symptoms was done by a urologist from the “voiding dysfunction unit” Urology Department, Cairo University Hospitals, with the severity of symptoms rated by the American Urological Association Symptom Score (AUASS) [11] at baseline, 3, 6, and 12 months. The AUASS range from 0 to 35, where 0–7 points are considered mild, 8–19 are moderate, and 20–35 are severe.
MRI brain and spinal cord (cervical and dorsal) with and without contrast were done for all patients using 1.5-T MRI machine (Achiva, Philips Medical system, the Netherlands) during the period of patient admission with the following sequences: Axial T1WI, T2WI, Sagittal T1WI, coronal T2WI, and Fluid Attenuated Inversion Recovery (FLAIR).
Post voiding abdominal and pelvic ultrasound, where a residual urine volume ≥ 100 ml is considered significant [12], ascending cystography, renal functions, and urine analysis were evaluated for all patients at baseline.
Urodynamic assessment (Laborie, Delphis KT, version 12 with ilist reporting system, Canada 2010) was done for all patients initially at baseline including filling cystoflowmetry, pressure flow study, and EMG of external sphincter, and the assessment was recorded by a computer-based device that consists of similar input sensors and amplification with the cystoflowmetry in the standing position or sitting in a urodynamic chair using 6- or 7-Fr dual-lumen urethral catheter along with either a rectal or vaginal catheter to assess extravesical pressure fluctuations. Urodynamic changes including the bladder volume at the first desire to void (ml), maximum bladder volume (ml), PdetQmax (cmH2O), postvoiding residual (PVR) (ml), electromyographic, Qmax (ml/s), and bladder compliance were measured. Detrusor overactivity, detrusor-sphincter dyssynergia, detrusor hypocontractility, and areflexia were defined according to the standardized definitions of lower urinary tract function by the international continence society (ICS) [13].
The patients were prescribed pharmacological treatment based on the nature of their symptoms and the therapeutic plan was modified according to patient’s responses, and interventions as clean intermittent catheterization (CIC) and botulinum toxin-A (Botox) were used whenever needed.
Statistical methods
Data was analyzed using the computer program Statistical package for the Social Science (SPSS version 22, IBM Corp, Armonk, NY, USA) released 2013 for Microsoft Windows. Mean and standard deviation (± SD) was used for numerical data while frequency and percentage for non-numerical data. Student t test was used to assess the statistical significance of the difference between means of the two studied groups. Mann-Whitney test (U test) was used to assess the statistical significance of the difference of a non-parametric variable between the two studied groups. Correlation analysis (using Pearson’s and Spearman’s rho method) assessed the strength of association between two quantitative variables. The correlation coefficient (r) defines the magnitude and direction (+ or −) of the linear relationship between two variables. Multivariate logistic regression analysis was done to test for the significant independent predictors of abnormal urodynamic, and linear model was used to test for the significant independent predictors of the urinary symptoms severity score. The probability/significance value (P value) ≥ 0.05 is not statistically significant and < 0.05 is statistically significant.