April 11, 2012 — Women with urinary incontinence (UI) who choose to take medication for the condition should consider the specific drug’s adverse effects as well as her own preferences when choosing the medical treatment, according to a new systematic review of randomized controlled trials on the safety and efficacy of drugs used to treat urgency.
Tatyana Shamliyan, MD, from the University of Minnesota School of Public Health, Minneapolis, and colleagues found that drugs available in the United States were more effective than a placebo in achieving continence and improving UI.
Such improvements, however, were small, and patients frequently discontinued treatment because of bothersome adverse effects, according to the authors.
The study was published online April 10 in the Annals of Internal Medicine.
"Our review has implications for clinical practice," the researchers write. "Since all drugs for urgency UI have comparable effectiveness, therapeutic choices should consider the harms profile, and women should be informed about all possible adverse effects."
The research will form the basis of upcoming guidelines developed by the American College of Physicians on treating UI.
Lifestyle changes and pelvic floor muscle and bladder training are standard treatments for women with urgency UI, the authors write. In addition, a few drugs have also been approved for adults who have loss of bladder control with or without urgency UI.
Researchers reviewed 94 published randomized controlled trials to determine the safety and efficacy of drugs available in the United States to treat urgency UI in community-dwelling adult women. They found the studies, published between 1996 and 2011, on MEDLINE and the Cochrane Central Register of Controlled Trials, among other data sources.
The authors chose to focus on continence and quality of life as the primary outcome measures, in part because previous reviews in this area have not emphasized continence or women’s perceptions of treatment success and satisfaction. A "clinically important" response to treatment was defined as a 50% or more decrease in episodes of daily UI.
The researchers also examined how adverse effects and adverse events influenced women’s decisions to stop treatment, as well as how the characteristics of women, including demographics, comorbidities, and type and severity of UI, can modify how effective a treatment is.
Data Are Lacking
There were only a few studies that compared 1 drug to another. In 1 study, fesoterodine was found to be more effective than tolterodine in terms of achieving continence and improving UI. Women were more likely to stop treatment because of adverse events when using fesoterodine or oxybutynin, however, rather than tolterodine, the authors note. In addition, 5 mg of the drug solifenacin was found to have the lowest rate of treatment discontinuation.
"Women with urgency UI whose prior treatments failed may benefit from solifenacin; however, they would not benefit from increasing the dose of the drug," the authors write.
They also found that oxybutynin, trospium, and darifenacin improved UI in older women, and trospium reduced the number of urgency UI episodes regardless of concomitant medications
"Adverse effects were more common in those taking seven or more concomitant medications," the authors note.
The researchers also found that evidence about long-term adherence and safety of drug treatments is lacking. They suggest that future research try to clarify which characteristics of women are associated with the greatest treatment benefits and the fewest adverse events. Such characteristics should include age, race, genitourinary characteristics, and comorbidities.
They go on to suggest that researchers design future studies to assess the long-term treatment success of drugs and make the primary outcome measure centered on women.
Outcomes should look at how likely a woman is to continue on the medication long term, whether episodes of UI are reduced by 50% to 70%, and whether there is any clinically important improvement in scales measuring the severity of UI and how it affects a woman’s quality of life, they write.
Upcoming research should also look at the safety of these drugs in populations of older women and populations of women with comorbidities, concomitant medications, and who have not had success with prior treatments, they note.
"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," the authors conclude.
This study is derived in part from work done for an evidence report commissioned by the US Agency for Healthcare Research and Quality. Three coauthors have received grants from the Agency for Healthcare Research and Quality. Full disclosures can also be viewed at http://www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=M11-1480.
Annals Intern Med. Published online April 9, 2012. Full text