Hypothesis / aims of study
Overactive bladder (OAB) is a common condition in patients older than 70 years of age and its prevalence increases with age. AUA guidelines recommend oral anticholinergics and b-3 agonists as second line therapy. However, these medications have been associated with negative cognitive effects and may negatively affect the blood pressure in elderly respectively. Furthermore, b-3 agonists do not have an acceptable formulary medication coverage, additional concern for elderly with limited insurance coverage. Currently there is lack of evidence assessing the outcomes of OnabotulinomtoxinA (BTX-A) injection as a third line OAB therapy, evaluating its efficacy and safety in the elderly population.
Study design, materials and methods
A retrospective chart review of patients seen at the Urology and Urogynecology clinic who underwent intradetrusor BTX-A from May 2015 to September 2021 was obtained. Patients older than 70 years of age at the time of their first injection were selected. Baseline characteristics, assessment of overactive bladder symptoms based on self-reported symptoms before and after injection were retrieved.
Results
141 patients over 70 years of age who had intradetrusor BTX-A were selected. 124 (88%) were female. Prior to injection 94% (132) were voiding spontaneously. Urinary urgency was the most common symptom in 97.3%, followed by urinary incontinence, daytime frequency in 93% and 85% respectively. The most common medications initially prescribed were anticholinergic in 74%, followed by b-3 agonist in 19%. The amount of BTX-A injected was 100U (89%) and 200U (6%).
Subgroup analysis by OAB symptom domain after BTX-A showed that patients noted a significant improvement in 73% for incontinence, 77% for urinary urgency, 72.5% daytime urinary frequency and 68% in nighttime frequency. Temporary de novo intermittent catheterization was initiated in four patients and one needed indwelling catheter placement. 57% returned for repeated injections due to good symptom response. Twenty-six (18%) had a symptomatic UTI at follow-up and 73% were not needing OAB medications after follow-up.
Subgroup analysis of patients who were over 80 years of age (n= 26/141) at the time of first BTX-A injection was performed. Twenty-two (85%) were female, 92% were voiding spontaneously, on initial presentation urinary urgency was reported in 26 (100%), urinary incontinence 96%, daytime urinary frequency in 73%. Medications initially prescribed were Anticholinergics in 50% and Beta 3 Agonists in 38%. The most common cause for undergoing BTX-A was no response to oral medications. Urinary urgency showed marked improvement on 81% and urinary incontinence of 73% of patients after injection. Symptomatic urinary tract infection was seen in 3 (12%) of this group of patients.
Interpretation of results
BTX-A is well tolerated in patients older than 70 with significant improvement in all OAB symptom domains and significant reduction of their oral OAB medication needs. This provides an option for patients to limit oral medications with unwanted side effects for this special population potentially at an earlier time in the OAB management algorithm.