FACTORS ASSOCIATED WITH DURABILITY OF THERAPEUTIC BOTULINUM TOXIN A INJECTION FOR OVERACTIVE BLADDER
Sources of Funding: None
Introduction
Patients suffering from overactive bladder (OAB) without response to behavioral and pharmaceutical intervention may opt for third?line therapy with botulinum toxin A injection. Botulinum injections have shown success in treating OAB urinary symptoms, but require repeat injections at an interval of 4?12 months. This study seeks to identify factors associated with the durability of this therapeutic effect.
Methods
Patients undergoing treatment for OAB at Lahey Hospital and Medical Center between 2004 and 2016 were identified. Demographic, clinical and treatment data were extracted from patient charts. Patients were included if they had at least 1 botulinum injections. Time from initial to second botulinum injection was defined as therapeutic durability; time from initial injection to last clinic follow?up was defined and time to event analyses were employed: univariate analysis via log?rank method and multivariate Cox proportional hazards were used to identify associations with therapeutic durability. The multivariate Cox model comprised univariate factors with p values below 0.1 and a priori clinical variables. Significance was defined at the ?= 0.05 level.
Results
Of the available patients, 54 patients met inclusion criteria. Median time to repeat injection for those who had a second injection was 259 days (8.6 months). Kaplan?Meier survival estimated that 50% of patients required reinjection at 330 days (11 months). On univariate analysis, history of spinal cord injury (p = 0.041), prostate cancer (p < 0.001), history of stroke/CVA (p=0.037), and history of UTI (p=0.013) were significantly associated with lower therapeutic durability. On multivariate analysis, only prostate cancer (OR 50.2, 95% CI 2.95?854, p = 0.0068) and history of UTI (OR 4.11, 95% CI 1.10?15.3, p = 0.035) were associated with lower therapeutic durability.
Conclusions
Botulinum injection showed a median durability of roughly 9 months. Patients with prostate cancer or a history of UTI had a statistically significantly lower durability of botulinum injection. Further study is warranted to identify further etiologic origins of these connections or elucidate other associated cofactors.
Funding
None
Jay Vance
Bennett Sluis
Jared Schober
Arthur Mourtzinos
Lara Maclachlan