title: New start versus continuing users on aripiprazole: implications for policy.
abstract: OBJECTIVE
  To evaluate utilization of 90-day-supply prescriptions of aripiprazole.
  
  
  METHODS
  One year (April 1, 2011, to March 31, 2012) retrospective cohort study from the Veterans Affairs San Diego Healthcare System.
  
  
  METHODS
  The primary outcome was to determine the difference in adherence for new starts versus continuing users on aripiprazole, as determined by medication possession ratio (MPR). Secondary outcomes included odds of adherence and refilling at least once associated with being a new start. Adherence was defined as MPR ≥ 0.8. Separate regression models (linear and logistic) were run for the entire population, as well as a subgroup analysis of 90-day prescription patients only.
  
  
  RESULTS
  A total of 749 patients, 328 of whom were new starts, were included in the analysis. Both new starts (41.2%) and continuing users (69.1%) had a large portion who received 90-day supplies. New-start patients had significantly lower MPR than continuing users (-0.13; 95% CI, -0.18 to -0.08). Logistic regressions showed that new starts also had lower odds of adherence (odds ratio [OR], 0.46; 95% CI, 0.33-0.65) and of refilling at least once (OR, 0.43; 95% CI, 0.28-0.66) compared with continuing users.
  
  
  CONCLUSIONS
  Patients who were continuing users of aripiprazole were more likely to be adherent and refill their medication. Overutilization of 90-day supplies of high-cost agents, particularly in new starts, may lead to waste. It is recommended that patients newly started on high-cost agents should initially be provided a 30-day-supply prescription until it is established that effectiveness and tolerance have been achieved.
authors.affiliation: Veterans Affairs San Diego Healthcare System, 3350 La Jolla Village Dr (119), San Diego, CA 92161. E-mail: rashid.kazerooni@va.gov.
authors.forename: Rashid
authors.initials: R
authors.lastname: Kazerooni
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Nguyen
authors.forename: Mark
authors.initials: M
authors.lastname: Bounthavong
authors.forename: Michael H
authors.initials: MH
authors.lastname: Tran
authors.forename: Nermeen
authors.initials: N
authors.lastname: Madkour
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D014150:Antipsychotic Agents / Q000008:administration & dosage*; D000068180:Aripiprazole / Q000008:administration & dosage*; D002140:California; D015331:Cohort Studies; D004363:Drug Utilization / Q000331:legislation & jurisprudence*; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology; D008875:Middle Aged; D011050:Policy Making; D012044:Regression Analysis; D012189:Retrospective Studies; D018570:Risk Assessment; D012737:Sex Factors; D013997:Time Factors; D014481:United States; D014493:United States Department of Veterans Affairs / Q000331:legislation & jurisprudence; D014728:Veterans / Q000706:statistics & numerical data; D016903:Drug Monitoring
chemical_list: D014150:Antipsychotic Agents; D000068180:Aripiprazole