title: Impact of Employer-Sponsored Onsite Pharmacy and Condition Management Programs on Medication Adherence.
abstract: BACKGROUND
  Poor medication adherence is associated with worsened health outcomes and higher health care expenditures. An increasing number of employers are sponsoring wellness initiatives designed to support healthy lifestyles, improve productivity, and offer a return on investment. Onsite pharmacies may facilitate higher medication adherence rates by providing employees a convenient, low-cost option for filling prescriptions that is integrated with other onsite health services.
  
  
  OBJECTIVE
  To (a) assess the impact of an employer's onsite pharmacy on health plan members' medication adherence using multiple measures of medication adherence and persistence, including medication possession ratio (MPR), average number of days until discontinuation (60-day gap in coverage), and percentage of members without a 30-day gap in coverage, and (b) evaluate these outcomes between those members who participated in condition management programs and those who did not.
  
  
  METHODS
  A retrospective analysis of a self-insured employer's claims data was undertaken. Medication adherence was assessed among the self-insured employer's health plan members, which included subscribers and their dependents who filled an asthma, depression, diabetes, hypertension, or hyperlipidemia medication at an onsite pharmacy, compared with those who used a community pharmacy. Multiple standard measures of medication adherence were considered. These measures included MPR, which was assessed for 1- and 2-year time periods. MPR was chosen because it is one of the most commonly referenced formulas in the literature and represents adherence over a fixed period of time. In addition, medication persistence was estimated by 30-day gaps in coverage and discontinuation of treatment. To assess the impact of onsite pharmacy use and account for covariate effects, the linear mixed model approach was applied with the logit transformed MPR as the response variable. An analysis of MPR among condition management participants was also performed.
  
  
  RESULTS
  In total, 2,498 subscribers and their dependents were included in the analysis. The average MPR at 365 days was significantly higher (P  <  0.0001) among onsite pharmacy users for all medication types, ranging from 13% higher for depression medications to 20% higher for hypertension medications. This trend persisted at 730 days (P  <  0.001), with average MPRs ranging from 6% higher for hyperlipidemia medications to 11% higher for hypertension medications. A mixed model analysis indicated that members who used the onsite pharmacy were 3.44 times more likely to demonstrate medication adherence (95% CI = 2.84-4.16; P  <  0.0001) at 365 days. Likewise, at 180 and 365 days, onsite pharmacy users were less likely to have 30-day gaps in treatment. The average number of days until discontinuation (defined as a 60-day gap) was also significantly longer (P  <  0.0001) among onsite pharmacy users, ranging from an average of 56 additional days for depression medications to 105 additional days for hypertension medications. While the average MPR tended to be higher among those subscribers and their dependents who participated in condition management programs, this trend was not statistically significant for all medication types.
  
  
  CONCLUSIONS
  Based on multiple measures, onsite pharmacy use was associated with higher medication adherence, while the results were inconclusive for condition management participation.
authors.affiliation: Cerner Research Consulting, 600 Corporate Pointe, Ste. 320, Culver City, CA 90230. Kat.Aguilar@cerner.com.
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Aguilar
authors.forename: Qingjiang
authors.initials: Q
authors.lastname: Hou
authors.forename: Ross M
authors.initials: RM
authors.lastname: Miller
mesh_terms: D000328:Adult; D019033:Delivery of Health Care, Integrated; D011307:Drug Prescriptions; D005260:Female; D006801:Humans; D016018:Least-Squares Analysis; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D055118:Medication Adherence; D008875:Middle Aged; D009786:Occupational Health Services; D010593:Pharmaceutical Services; D015397:Program Evaluation; D012189:Retrospective Studies; D013997:Time Factors; D017132:Workplace