title: Risk of medication-associated initiation of oxybutynin in elderly men and women.
abstract: OBJECTIVE
  To determine whether there is greater risk of initiation of oxybutynin to treat urinary incontinence (UI) after initiation of medicines reported to be associated with UI.
  
  
  METHODS
  Prescription sequence symmetry analysis (PSSA).
  
  
  METHODS
  Administrative claims data from the Australian Government Department of Veterans' Affairs.
  
  
  METHODS
  Individuals who initiated oxybutynin and a medicine reported to be associated with UI in a 12-month period.
  
  
  METHODS
  Between January 1, 2001, and December 31, 2011, the distribution of incident dispensing of medicines reported to be associated with UI (prazosin, diuretics, calcium channel blockers (CCBs), angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), hormone replacement therapy (HRT), opioid analgesics, anticonvulsants, levodopa, antipsychotics, sedatives, selective serotonin reuptake inhibitors (SSRIs), venlafaxine, anticholinesterases) was assessed before and after incident dispensing of oxybutynin (to treat UI). Crude and adjusted sequence ratios (ASRs) with 95% confidence intervals (CIs) were calculated.
  
  
  RESULTS
  Significant associations between initiation of CCBs, ACEIs, ARBs, and hypnotic-sedatives and subsequent initiation of oxybutynin were found. ASRs ranged from 1.28 (95% CI = 1.19-1.39) for ACEIs to 1.59 (95% CI = 1.29-1.96) for verapamil. In women, there was greater risk of initiation of oxybutynin after prazosin (ASR = 1.84, 95% CI = 1.29-2.63) and HRT (ASR = 1.54, 95% CI = 1.42-1.67) initiation. PSSA showed no significant association with initiation of opioids, anticonvulsants, levodopa, SSRIs, venlafaxine, or anticholinesterases and subsequent initiation of oxybutynin.
  
  
  CONCLUSIONS
  This study highlights the potential for initiation of commonly used medicines to be associated with subsequent initiation of oxybutynin to treat UI. Greater awareness of the potential for medicines to contribute to UI is required.
authors.affiliation: Quality Use of Medicines and Pharmacy Research Centre, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Kalisch Ellett
authors.forename: Nicole L
authors.initials: NL
authors.lastname: Pratt
authors.forename: John D
authors.initials: JD
authors.lastname: Barratt
authors.forename: Debra
authors.initials: D
authors.lastname: Rowett
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Roughead
mesh_terms: D058668:Adrenergic alpha-1 Receptor Antagonists / Q000627:therapeutic use; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D006787:Hospitals, Veterans; D006801:Humans; D006973:Hypertension / Q000188:drug therapy; D008297:Male; D008333:Mandelic Acids / Q000008:administration & dosage / Q000009:adverse effects*; D010276:Parasympatholytics / Q000008:administration & dosage / Q000009:adverse effects; D015995:Prevalence; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012737:Sex Factors; D013021:South Australia / Q000453:epidemiology; D014549:Urinary Incontinence / Q000139:chemically induced* / Q000453:epidemiology
chemical_list: D058668:Adrenergic alpha-1 Receptor Antagonists; D008333:Mandelic Acids; D010276:Parasympatholytics; C005419:oxybutynin
keywords: aged; medications; pharmacoepidemiology; urinary incontinence