Treatment of Overactive Bladder with Onabotulinumtoxin-A in Elderly Patients With Central Nervous System Disorders

Onabotulinumtoxin-A (BoNT-A) is prescribed to treat both overactive bladder (OAB) and urinary incontinence due to detrusor overactivity associated with neurologic conditions in adult patients who have had an inadequate response to treatment with anticholinergic medication. Although the drug is frequently given
to older adults for these indications, there is limited data about treatment outcomes and safety specifically among elderly persons with dementia, Parkinson’s disease, and chronic cerebrovascular accidents (CVAs).

At ICS 2014, Chun-Hou Liao, department of urology, Cardinal Tien Hospital and School of Medicine, Fu-Jen Catholic University, New Taipei, Taiwan, and colleagues presented the results of a study that investigated safety and efficacy of BoNT-A in a cohort of 40 elderly patients (mean age, 74.6 years) with OAB due to CVAs, Parkinson’s disease, and dementia. In these patients, OAB was refractory to antimuscarinic therapy. The mean duration of central nervous system (CNS) lesions from diagnosis was 4.3 years. An age-matched cohort of 160 patients (mean age, 74 years) with OAB without CNS lesions served as the control group. Both groups received BoNT-A 100 U injected into the bladder sub-urothelium at 20 sites. Clinical outcomes were assessed at baseline and 3 months after treatment. Urgency episodes and urgency urinary incontinence were identified using a voiding diary that patients kept for 3 days and an urgency severity score (USS) questionnaire; an improvement on this questionnaire of 1 or more points was considered an improvement in OAB symptoms.

The results showed no statistically significant differences in voiding diaries, USS, and urodynamic parameters between the patient groups at 3 months after treatment, and long-term success rates were comparable between the patient groups. With regard to safety, patients with CNS lesions did not experience increased risk of acute urinary retention or urinary tract infection; however patients with CVA experienced an increased rate of straining (73.9%).

The authors of the study concluded that although adverse events were acceptable and long-term effects were comparable in both groups, “the possibility of long-standing urinary retention and chronic catheterization need careful evaluation for this very vulnerable population before choosing intravesicle BoNT-A treatment.” The study was published in PLoS One. The authors reported no relevant financial relationships and no sources of support or funding.

—Allison Musante