To evaluate the impact of functional bladder capacity (FBC) on clinical outcomes after a staged neuromodulation procedure.
Adults in our prospective neuromodulation database were evaluated. Data were collected from medical records, voiding diaries (FBC defined as average volume per void), Interstitial Cystitis Symptom/Problem Indices (ICSI-PI), Overactive Bladder Questionnaires (OAB-q), and Global Response Assessments over 3 months. Descriptive statistics, Pearson's Chi-square tests, Wilcoxon rank sum tests, logistic regression, repeated measures analyses and Spearman Correlation Coefficients were performed.
Of 216 patients (mean age 59 years; 84% female), most had urinary urgency/frequency with/without urge incontinence (71%), a sacral lead placed (82%) and implantable pulse generator (IPG) implantation (92%). Baseline FBC was similar between implanted/not implanted patients (p=0.17), however implanted patients had a median 19 ml increase in FBC after lead placement compared to a 2.7 ml decrease in explanted patients (p=0.0014). There was a strong association between percent change in FBC after lead placement and IPG implantation (p=0.021; C-statistic 0.68) but baseline FBC (ml) was not associated. Baseline FBC (ml), or percent change in FBC after lead placement, was not related to symptom improvement. When grouped by baseline FBC <150 and ≥ 150ml, FBC only improved significantly in the <150 group but both demonstrated significant improvements in symptoms.
FBC improvements were associated with IPG implantation but not other symptom measures. Patients with low FBC (baseline FBC < 150) also achieved significant improvements in symptoms.
Urology. 2017 Jan 13 [Epub ahead of print]
Kim A Killinger, Priyanka Gupta, Jason P Gilleran, Jamie Bartley, Michael Ehlert, Judith A Boura, Kenneth M Peters
Beaumont Health, Royal Oak, MI; Oakland University William Beaumont School of Medicine, Rochester, MI. Electronic address: ., University of Michigan, Ann Arbor, MI., Beaumont Health, Royal Oak, MI; Oakland University William Beaumont School of Medicine, Rochester, MI., Metro Urology, Woodbury, MN.