title: Cost comparison of drug-drug and drug-condition interactions in patients with painful diabetic peripheral neuropathy treated with pregabalin versus duloxetine.
abstract: OBJECTIVE
  The frequency and financial impact of potential drug-drug interactions (DDIs) and drug-condition interactions (DCIs) in patients with painful diabetic peripheral neuropathy (DPN) treated with either pregabalin or duloxetine were compared.
  
  
  METHODS
  This retrospective cohort study was conducted using a large U.S. administrative claims database. Patients selected for study inclusion had a diagnosis of DPN and were newly initiated on either pregabalin or duloxetine between July 1, 2008, and October 1, 2010. Data on potential DDIs and DCIs were collected. Health care costs were measured as the sum of gross covered payments for all medical and prescription claims incurred during the six months after the index date.
  
  
  RESULTS
  The study sample comprised 2499 pregabalin users and 1354 duloxetine users. Among pregabalin users, 48 (1.8%) had at least one potential pregabalin DCI; none had potential pregabalin DDIs. Among duloxetine users, 966 (71%) had at least one potential duloxetine DDI or DCI. The frequencies of potential DDIs and DCIs differed significantly between pregabalin and duloxetine users (p < 0.001). Potential duloxetine DDIs and DCIs were associated with a significant increase in mean health care costs in duloxetine users (p = 0.002). Potential pregabalin DDIs and DCIs were not associated with additional health care costs in pregabalin users.
  
  
  CONCLUSIONS
  Among patients with painful DPN treated with either pregabalin or duloxetine, the frequency of potential duloxetine DDIs and DCIs was substantially higher than that of pregabalin. Potential DDIs and DCIs were associated with significantly increased health care costs in duloxetine users.
authors.affiliation: Stephen S. Johnston, M.A., is Research Leader, Truven Health Analytics, Bethesda, MD. Margarita Udall, M.P.H., is Associate Director; and Joseph C. Cappelleri, M.P.H., Ph.D., is Senior Director, Pfizer, New York, NY. Barbara H. Johnson, M.B.A., is Analyst Manager; George Shrady, M.S., is Programmer; and Bong-Chul Chu, Ph.D., is Senior Statistician, Truven Health Analytics. Stuart L. Silverman, M.D., FACP, FACR, is Medical Director, Bone Health Center, Cedars-Sinai Medical Center, Los Angeles, CA.
authors.forename: Stephen S
authors.initials: SS
authors.lastname: Johnston
authors.forename: Margarita
authors.initials: M
authors.lastname: Udall
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Cappelleri
authors.forename: Barbara H
authors.initials: BH
authors.lastname: Johnson
authors.forename: George
authors.initials: G
authors.lastname: Shrady
authors.forename: Bong-Chul
authors.initials: BC
authors.lastname: Chu
authors.forename: Stuart L
authors.initials: SL
authors.lastname: Silverman
mesh_terms: D000368:Aged; D000700:Analgesics / Q000009:adverse effects / Q000191:economics / Q000627:therapeutic use*; D015331:Cohort Studies; D016208:Databases, Factual; D003929:Diabetic Neuropathies / Q000188:drug therapy* / Q000191:economics; D000068736:Duloxetine Hydrochloride; D005260:Female; D017048:Health Care Costs; D006801:Humans; D008297:Male; D008875:Middle Aged; D000069583:Pregabalin; D012189:Retrospective Studies; D013876:Thiophenes / Q000009:adverse effects / Q000191:economics / Q000627:therapeutic use*; D014481:United States; D005680:gamma-Aminobutyric Acid / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000191:economics / Q000627:therapeutic use
chemical_list: D000700:Analgesics; D013876:Thiophenes; D000069583:Pregabalin; D005680:gamma-Aminobutyric Acid; D000068736:Duloxetine Hydrochloride