title: Evaluation of Abuse-Deterrent or Tamper-Resistant Opioid Formulations on Overall Health Care Expenditures in a State Medicaid Program.
abstract: BACKGROUND
  The development of abuse-deterrent opioid prescription medications is a priority at the national level. Pharmaceutical manufacturers have begun marketing new formulations of currently available opioids that meet higher abuse resistance standards. Little information is available regarding the impact of these formulations on overall health care expenditures.
  
  
  OBJECTIVE
  To (a) examine the relationship between health care expenditures and use of brand abuse-deterrent or tamper-resistant (ADTR) extended-release opioids versus standard dosage form (SDF) extended-release opioids in a state Medicaid population, and (b) determine whether this relationship was influenced by member-specific characteristics.
  
  
  METHODS
  The study is a cross-sectional review of Oklahoma Medicaid members (aged ≥ 21 years) with at least 1 paid pharmacy claim for long-acting opioids between September 2013 and August 2014. Members who were adherent to extended-release opioid products were classified into ADTR and SDF opioid groups. The relationship between health care expenditures (prescription, medical, and overall) and opioid groups was examined using multiple linear regression models. The impact of member-specific characteristics (age, sex, race, urban classifications, and various comorbidities) on this relationship was examined.
  
  
  RESULTS
  Prescription spending ($9,265,554) accounted for 35% of overall health care expenditures ($26,304,693) among 938 members during the 12-month reference period. Total prescription expenditures were higher among ADTR than SDF user groups, and the difference in median expenditures between these 2 groups was larger among members with more comorbidities, as measured by the Charlson Comorbidity Index score. Overall, ADTR users had higher median total health care and medical expenditures, and the difference in median expenditures was dependent on whether a member had comorbidities of addiction or not (higher expenditures were observed among members with comorbidities of addiction).
  
  
  CONCLUSIONS
  The abuse and misuse of medically prescribed opioid products is a growing health epidemic. A variety of attempts have been made to reduce the potential of abuse and misuse of these products, including changes to product formulations. The results of this study indicate that both prescription spending and physician and pharmacy spending combined may be increased with the use of these new products because of higher pricing. Study findings also suggest that the use of ADTR opioids among members with comorbidities of addiction may be related to slightly lower overall health care and medical expenditures than those among members without comorbidities of addiction. Further research is required to answer questions regarding the comparative effectiveness of existing opioid prescription formulations.
  
  
  BACKGROUND
  No outside funding supported this research. Nesser is employed by the Oklahoma Health Care Authority, and Keast is a contractual employee for the Oklahoma Health Care Authority. The authors declare no other conflicts of interest. Study design was primarily contributed by Keast, along with Nesser and Farmer. Keast took the lead in data collection, while data interpretation was primarily performed by Owora, along with Keast and assisted by Nesser and Farmer. The manuscript was written and revised by all authors equally.
authors.affiliation: 1 Assistant Professor, University of Oklahoma College of Pharmacy, Oklahoma City, Oklahoma.
authors.forename: Shellie L
authors.initials: SL
authors.lastname: Keast
authors.affiliation: 2 Research Biostatistician, University of Oklahoma College of Pharmacy, Oklahoma City, Oklahoma.
authors.forename: Arthur
authors.initials: A
authors.lastname: Owora
authors.affiliation: 3 Pharmacy Director, Oklahoma Health Care Authority, Oklahoma City, Oklahoma.
authors.forename: Nancy
authors.initials: N
authors.lastname: Nesser
authors.affiliation: 4 Professor, University of Oklahoma College of Pharmacy, Oklahoma City, Oklahoma.
authors.forename: Kevin
authors.initials: K
authors.lastname: Farmer
mesh_terms: D000328:Adult; D000701:Analgesics, Opioid / Q000008:administration & dosage* / Q000009:adverse effects / Q000191:economics; D002626:Chemistry, Pharmaceutical; D015897:Comorbidity; D003430:Cross-Sectional Studies; D003692:Delayed-Action Preparations; D004345:Drug Industry / Q000191:economics; D005260:Female; D005102:Health Expenditures; D006801:Humans; D016014:Linear Models; D008297:Male; D008484:Medicaid / Q000191:economics; D008875:Middle Aged; D009825:Oklahoma; D009293:Opioid-Related Disorders / Q000517:prevention & control*; D063487:Prescription Drug Misuse / Q000517:prevention & control*; D012189:Retrospective Studies; D014481:United States
chemical_list: D000701:Analgesics, Opioid; D003692:Delayed-Action Preparations