Persistence of antimuscarinic drug use.
OBJECTIVE
Evidence suggests antimuscarinic drugs for the overactive-bladder syndrome only confer modest improvements in quality of life. We wanted to describe the persistence of therapy, including an extended analysis beyond the 1-year follow-up employed in other studies.


METHODS
All prescriptions for drugs in ATC category G04BD were retrieved for the period 1999-2006 from a regional database with complete capture of all reimbursed prescriptions. Kaplan-Meyer curves were generated for duration of treatment for each substance and analyzed for determinants of termination.


RESULTS
With the exception of trospium chloride, all drugs had continuation rates of less than 50% at 6 months, less than 25% at 1 year, and less than 10% at 2 years and longer. Trospium chloride, however, exhibited continuation rates of 46% at 6 months, 36% at 1 year, 22% at 2 years, and 16% at 3 years.


CONCLUSIONS
In a setting of socialized medicine, we found higher continuation rates than previously published. Interestingly, we found that one of the older drugs on the market, trospium chloride, had a strikingly longer retention rate than other drugs.
Brostrøm
Søren
S
Department of Obstetrics and Gynecology, Glostrup Hospital, DK-2600, Glostrup, Denmark. soren@brostrom.dk.
Hallas
Jesper
J
D000368:Aged; D001561:Benzilates; D016208:Databases, Factual; D003718:Denmark; D004334:Drug Administration Schedule; D011307:Drug Prescriptions / Q000706:statistics & numerical data*; D004363:Drug Utilization; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D018727:Muscarinic Antagonists / Q000008:administration & dosage* / Q000627:therapeutic use*; D009662:Nortropanes / Q000627:therapeutic use; D010349:Patient Compliance / Q000706:statistics & numerical data*; D011788:Quality of Life; D053201:Urinary Bladder, Overactive / Q000188:drug therapy*
D001561:Benzilates; D018727:Muscarinic Antagonists; D009662:Nortropanes; C003330:trospium chloride