Introduction and hypothesis: Our objective was to estimate the prevalence and sociodemographic factors associated with anticholinergic medication use by adult women for overactive bladder (OAB) in the United States.
Methods: We conducted a cross-sectional study using the 2009 National Ambulatory Medical Care Survey database (NAMCS). We included women aged 18 years and older and identified visits for which anticholinergic medications for OAB were in active use. We evaluated the prevalence of medications used and estimated the use of short-acting versus long-acting drugs. We also assessed variables associated with anticholinergic use, (age, race/ethnicity, insurance, geographic location) using survey weights in the analysis to estimate national data.
Results: In 2009, adult women made 516.8 million outpatient office visits. Of these, 8.1 million (1.6 %) were associated with an OAB anticholinergic medication (annual rate 68 per 1,000 women). Women who used anticholinergics were predominantly insured by Medicare (61.0 %) and were older than those not using anticholinergic medications (70.0 ± 1.1 vs. 53.0 ± 0.5, p < 0.001). No racial or ethnic differences were evident between the two groups. Tolterodine (33.8 %) and oxybutynin (33.1 %) were the most commonly reported medications, followed by solifenacin (19.5 %), darifenacin (9.3 %), and trospium (4.4 %). Long-acting anticholinergics were used more often than short-acting medications (53.8 % vs. 46.3 %, respectively, p < 0.001).
Conclusions: Annually, more than 8 million outpatient visits occur in which adult women in the United States are using an OAB anticholinergic medication. Despite the abundance of newer-generation medications, tolterodine and oxybutynin remain the most commonly prescribed anticholinergic drugs for OAB. Solifenacin is the most popular newer-generation anticholinergic drug.