title: Dispensing channel and medication adherence: evidence across 3 therapy classes.
abstract: OBJECTIVE
  To examine the association of mail order versus retail pharmacy dispensing channels with medication adherence for patients on diabetes, hypertension, or high blood cholesterol medications, controlling for prior adherence behavior (PAB) and days of supply.
  
  
  METHODS
  Retrospective analysis using de-identified pharmacy claims data from a large national pharmacy benefits manager between April 2009 and December 2011.
  
  
  METHODS
  Continuously eligible patients with an antidiabetic, antihypertensive, or antihyperlipidemic prescription claim between October and December 2009 were identified and followed over a 2-year period. Multivariate logistic regression was used to evaluate the impact of dispensing channel on medication adherence, controlling for differences in demographics, disease burden, and drug use pattern. Patients with a medication possession ratio of 80% or greater were considered adherent. The analysis controlled for PAB by using patients' adherence status in 2010.
  
  
  RESULTS
  Overall, patients using the mail order channel had higher adherence rates than their retail counterparts across all 3 therapeutic classes. In 2011, the likelihood of a mail order patient being adherent was approximately 1.15 times higher than that of a retail patient for antidiabetics, 1.11 times higher for antihypertensives, and 1.19 times higher for antihyperlipidemics. PAB was the strongest contributor to the odds of a patient being adherent across all 3 therapy classes: odds ratios ranged from 5.87 to 9.49.
  
  
  CONCLUSIONS
  After adjusting for PAB, differential days of supply, and differences in demographics and disease burden, patients who use mail order have a greater likelihood of being adherent than patients who use a retail pharmacy.
authors.affiliation: Research and New Solutions, Express Scripts, 4600 N Hanley Rd, PTIC08, St Louis, MO 63134. E-mail: rniyengar@express-scripts.com.
authors.forename: Reethi
authors.initials: R
authors.lastname: Iyengar
authors.forename: Rochelle
authors.initials: R
authors.lastname: Henderson
authors.forename: Jay
authors.initials: J
authors.lastname: Visaria
authors.forename: Sharon
authors.initials: S
authors.lastname: Glave Frazee
mesh_terms: D000293:Adolescent; D000328:Adult; D002908:Chronic Disease / Q000188:drug therapy*; D006801:Humans; D007345:Insurance Claim Review; D016015:Logistic Models; D055118:Medication Adherence; D008875:Middle Aged; D010593:Pharmaceutical Services; D010594:Pharmacies; D011177:Postal Service; D012189:Retrospective Studies; D055815:Young Adult