Anticholinergic therapy and onabotulinumtoxinA appear equally effective for urgency urinary incontinence

Oral anticholinergic therapy and injection onabotulinumtoxinA appear to be equally effective for treating urgency urinary incontinence, according to a new trial.

To compare these two treatments, researchers performed a double-blind, double placebo-controlled, randomized trial of women who reported having five or more episodes of idiopathic urgency urinary incontinence per three-day period. For six months, women were randomly assigned to receive an oral anticholinergic daily (5 mg of solifenacin with potential to escalate to 10 mg or subsequently switch to 60 mg of trospium XR if necessary) plus an intradetrusor saline injection, or to receive a single 100-U intradetrusor injection of onabotulinumtoxinA, a form of purified botulinum toxin type A, plus an oral placebo daily. Study participants kept three-day diaries of urinary incontinence episodes and submitted them monthly.

The study's primary outcome measure was reduction from baseline in mean urgency urinary incontinence episodes per day over six months, according to the diaries. Secondary outcomes were resolution of incontinence, catheter use, adverse events and quality of life. The study results were published Oct. 4 by the New England Journal of Medicine.

Two hundred forty-nine women were randomly assigned to a treatment group, 247 were treated, and data from 241 were included in the primary outcome analysis. At baseline, 41% reported never having received previous anticholinergic therapy. The baseline average of urgency urinary incontinence episodes was 5.0 per day, and the mean reduction per day over six months was 3.4 in the anticholinergic group and 3.3 in the onabotulinumtoxinA group (P=0.81). Both groups showed similar improvement in quality of life. Thirteen percent of women in the anticholinergic group and 27% in the onabotulinumtoxinA group reported complete resolution of urinary incontinence (P=0.0003). Dry mouth was more common in the anticholinergic group (46% vs. 31%; P=0.02), but catheter use at two months (0% vs. 5%; P=0.01) and urinary tract infections (13% vs. 33%; P<0.001) were less common.

The authors noted that they studied the effects of only one injection of one type of botulinum toxin A and that they could not discount the possibility of a placebo effect. However, they concluded that both treatments led to similar reductions in episodes of urgency urinary incontinence, with different side effects.

“The choice between these therapies should take into account the differing regimens and routes of administration and the side-effect profiles, including more frequent occurrence of dry mouth with anticholinergic medication and higher risks of intermittent catheterization and urinary tract infection with onabotulinumtoxinA,” the authors wrote.