US study says drugs of limited benefit in treating urine leakage in women
Monday, 16 April 2012- There are few data to show that drugs for urge urinary incontinence improve quality of life or have differences in comparative efficacy, according to a US government-commissioned study.
The review of randomized clinical trials showed that 8.5% to 13% of patients achieved continence with the different drugs, whereas adverse effects led to discontinuation of treatment in as many as 6.3% of cases, according to an article published online in Annals of Internal Medicine.
Inconsistency in the definitions of improvement in symptoms and quality of life complicated data analysis, noted Dr. Tatyana Shamliyan of the University of Minnesota School of Public Health in Minneapolis, and co-authors.
"Since all of the drugs for urgency urinary incontinence have comparable effectiveness, therapeutic choices should consider the harms profile, and women should be informed about possible adverse effects," they wrote. "Benefits from drugs are small, with fewer than 200 cases of continence attributable per 1,000 treated. Compliance rates for prescription drugs are low; discontinuation due to bothersome side effects is common."
"In light of the lack of good evidence about long-term benefits of and adherence to drugs, these should be closely monitored and routinely analyzed in clinical settings," they added.
First-line treatment for urge urinary incontinence includes lifestyle changes and pelvic-floor muscle and bladder training. Additionally, several drugs have been approved for overactive bladder with or without urgency incontinence. Although continence is the most meaningful outcome of treatment, most studies and reviews have focused on changes in urinary frequency. Neither continence nor women's views of treatment success and satisfaction have received much attention, the authors wrote in their introduction.
As part of an evidence report commissioned by the Agency for Healthcare Research and Quality, Shamliyan and colleagues examined the comparative effectiveness of drug therapy for urinary incontinence in women. A systematic literature review identified 94 randomized controlled trials suitable for inclusion in the analysis of data.
Most of the trials were conducted in Western countries, and women accounted for more than 80% of the study populations. Fewer than half of the trials included minorities, and none of the authors reported outcomes by racial subgroups.
The trials included a mix of urinary incontinence subtypes, and more than a third did not report patient distribution by type of incontinence. More than 40% of the studies included women with a history of drug treatment for incontinence, 13% enrolled only patients with no prior drug treatment for incontinence, and 45% of the publications did not state patients' treatment status.
Drugs represented in the review were fesoterodine (Toviaz), tolterodine (Detrol), oxybutynin, solifenacin (Vesicare), and trospium. As compared with placebo, all of the drugs were more effective for achieving continence. Pooled analyses showed that continence rates ranged from 85 per 1,000 treated with tolterodine to 130 per 1,000 with fesoterodine.
Drug treatment was associated with more adverse effects than was placebo. The adverse effect most often associated with drug treatment was dry mouth. Discontinuation rates ranged from 13 per 1,000 treated with solifenacin to 63 per 1,000 with oxybutynin.
The authors identified 21 publications of comparative randomized trials. The results of those trials showed:
• Fesoterodine was more effective than tolterodine for achieving continence and improving incontinence symptoms
• Trospium was more effective than oxybutynin
• Solifenacin was more effective than tolterodine
"Overall, our findings demonstrated good evidence that rates of continence and clinically important improvement in urinary incontinence were greater with drugs than with placebo, but drugs also resulted in treatment discontinuation due to bothersome adverse effects," the authors wrote in the discussion of their findings.
"The drugs examined in well-designed randomized controlled trials were better than placebo with similar effectiveness," they added. "However, with some drugs, more women discontinued treatment due to bothersome side effects."
Source: T. Shamliyan, et al., "Benefits and harms of pharmacological treatment for urinary incontinence in women: a systematic review," Annals of Internal Medicine 2012; epub. MedPage Today.