Introduction and hypothesis: Intradetrusor onabotulinumtoxinA (BTX) and sacral neuromodulation (SNM) are effective treatments for refractory urgency urinary incontinence/overactive bladder (UUI/OAB). BTX carries a risk of urinary tract infection (UTI), which is concerning for the development of multidrug resistant (MDR) UTI. We hypothesized that BTX might carry a higher risk of UTI and MDR UTI compared with SNM and that UTI and MDR UTI risk might increase after repeat BTX injection.
Methods: This retrospective cohort study included women undergoing BTX or SNM for refractory UUI/OAB in 2012-2016. UTI and MDR UTI were assessed up to 1 year post-treatment or until repeat treatment and compared between initial BTX and SNM and between repeat BTX injections. Univariate analyses included Chi-squared and Fisher's exact tests and generalized linear models (GLM) with logit link function. Multivariate analyses used GLM to assess the best predictor variables for any UTI.
Results: One hundred and one patients were included (28 BTX, 73 SNM). Rates of UTI (39.3% [95% CI 21.5, 59.4] BTX vs 37.0% [95% CI 26.0, 49.1] SNM) were similar in the two groups at all time intervals. One MDR UTI occurred after SNM. Risk of UTI did not increase with repeat BTX (11 out of 28 [39.3%], 6 out of 17 [35.3%], and 4 out of 7 [57.1%] after 1, 2, and ≥ 3 treatments respectively; p = 0.62). Multivariate analysis found that history of recurrent UTI (OR 2.5, 95%CI 0.98-6.39) and prolapse repair (OR 4.6, 95%CI 1.23-17.07) had increased odds of UTI.
Conclusions: Rates of UTI were similar in patients undergoing BTX and SNM. MDR UTI was rare. Patients with prior prolapse repair or recurrent UTI may be at a higher risk of UTI after either procedure.
Keywords: Drug resistance; OnabotulinumtoxinA; Sacral neuromodulation; Urgency urinary incontinence; Urinary tract infection.