Voiding DysfunctionRepeated Botulinum Toxin Type A Injections for Refractory Overactive Bladder: Medium-Term Outcomes, Safety Profile, and Discontinuation Rates
Introduction
Injections of botulinum toxin type A (BoNTA) into the bladder is an effective treatment for patients with idiopathic detrusor overactivity (IDO) and symptoms of overactive bladder (OAB). Over the last 5 yr, data from several randomised, double-blind, placebo-controlled trials have demonstrated its safety and efficacy after one injection [1], [2], [3]. A large, phase 2, dose-escalation, industry-sponsored study confirmed its efficacy in doses of ≥100 U compared with placebo, with significant improvement in OAB symptoms, urodynamic parameters, and quality of life (QoL) [4], [5]. A European consensus group gave a grade A recommendation for BoNTA use in IDO and a recent systematic review suggested its use for refractory OAB is well justified [6], [7].
Many patients have come to rely on repeated injections for continued control of OAB symptoms. To date there have only been few small series reporting the outcomes of repeated injections in patients with IDO [8], [9]. In this study we seek to expand on our previous work by reporting outcomes in our first 100 patients with a particular focus on efficacy, safety, and the proportion of patients who chose to discontinue BoNTA injections as a long-term strategy and the reasons for their choice.
Section snippets
Patients and methods
Patients were adults (>18 yr) of both sexes who had OAB symptoms and IDO. All patients had failed treatment with at least one antimuscarinic medication (often multiple antimuscarinics had been tried for at least 4–6 wk unless there were tolerability issues) and had urodynamics performed within 12 mo of injection. All urodynamic procedures were performed as recommended by the International Continence Society [10]. OnabotulinumtoxinA injections were first offered in our unit as part of a clinical
Results
Between 2004 and 2010, 207 injections were performed in 100 patients. Median age at first injection was 55 yr (range: 22–85 yr); 76 patients were female. Table 1 outlines the number of injections each patient received, the number of patients who chose to discontinue injections, and the reasons they gave for stopping. After the first and second injections, 25 patients (25%) and 12 patients (22%), respectively, did not undergo further injections at our institution. Subsequently, the vast majority
Discussion
In this study we have reported our clinical experience of onabotulinumtoxinA as a medium-term management strategy for IDO. Our data reflect the outcomes for 100 patients who commenced their therapy with onabotulinumtoxinA in a staggered fashion over a reporting period of approximately 6 yr. Therefore, one would not expect all 100 patients to have had the same number of repeat injections and thus we saw a decreasing number of patients at each stage. The key question is whether this represents a
Conclusions
To our knowledge, this is the largest series to date reporting on repeated onabotulinumtoxinA injections in patients with refractory IDO. The data suggest that the toxin can provide an efficacious and safe repeated therapy for managing refractory OAB symptoms in the medium term. Discontinuation rates are most likely related to poor efficacy and the need to perform CISC. Further research into optimum delivery and dosage according to individual patient information may improve the number of
References (19)
- et al.
Efficacy of botulinum toxin-A for treating idiopathic detrusor overactivity: results from a single center, randomized, double-blind, placebo controlled trial
J Urol
(2007) - et al.
Refractory idiopathic urge urinary incontinence and botulinum A injection
J Urol
(2008) - et al.
Outcome of a randomized, double-blind, placebo controlled trial of botulinum A toxin for refractory overactive bladder
J Urol
(2009) - et al.
Efficacy and safety of onabotulinumtoxinA for idiopathic overactive bladder: a double-blind, placebo controlled, randomized, dose ranging trial
J Urol
(2010) - et al.
Recommendations on the use of botulinum toxin in the treatment of lower urinary tract disorders and pelvic floor dysfunctions: a European consensus report
Eur Urol
(2009) - et al.
Contemporary management of lower urinary tract disease with botulinum toxin A: a systematic review of Botox (onabotulinumtoxinA) and Dysport (abobotulinumtoxinA)
Eur Urol
(2011) - et al.
What a patient with refractory idiopathic detrusor overactivity should know about botulinum neurotoxin type a injection
J Urol
(2009) - et al.
Repeated injections of botulinum toxin-A for idiopathic detrusor overactivity
Urology
(2010) - et al.
Neurogenic detrusor overactivity treated with English botulinum toxin A: 8-year experience of one single centre
Eur Urol
(2008)