title: Medication adherence, healthcare costs and utilization associated with acne drugs in Medicaid enrollees with acne vulgaris.
abstract: BACKGROUND
  Acne vulgaris is a common chronic disease that may require long-term treatment. Medication adherence is critical to acne management; non-adherence is a common reason for treatment failure and can lead to poor quality of life.
  
  
  OBJECTIVE
  The aim of the study was to examine medication adherence, healthcare costs, and utilization associated with acne drugs among acne patients in the USA.
  
  
  METHODS
  This was a retrospective cohort study from January 2004 to December 2007 using the Marketscan Medicaid Database, a national healthcare claims database. The study followed acne patients aged 0-64 years for 90 days after the first acne drug prescription to measure acne medication adherence, acne-related outpatient visits, and total acne-related healthcare costs. Adherence was measured among different acne drug classes using medication possession ratio (MPR). Multivariate regression analyses were conducted to assess the outcomes.
  
  
  RESULTS
  The study included 24,438 eligible patients, of whom 89.39 % were under 18 years old. The average adherence rate to acne drugs (MPR) was 0.34, and only 11.74 % of the patients were adherent (MPR ≥0.80). Patients with drug refills had a higher adherence rate (MPR = 0.74) than who those without refills (MPR = 0.27). Factors significantly associated with adherence were age, comorbidity, gender, number of drug refills and number of drug classes used. Patients were more adherent to oral retinoids than any other acne drug classes (MPR = 0.78, 57 % adherent). Patients were less adherent to oral antibiotics (MPR = 0.21) and topical retinoids (MPR = 0.31). After controlling for medication use behavior, the use of oral antibiotics decreased the number of acne-related outpatient visits by 50.9 % (p < 0.001) and lowered acne-related total costs by 51.7 % (p < 0.001).
  
  
  CONCLUSIONS
  Medication non-adherence is generally prevalent among young acne patients enrolled in Medicaid. The combination of a topical retinoid and an antibiotic agent may be a good choice given their associated healthcare outcomes and costs. However, adherence to these agents is not satisfactory. Therefore, developing specific strategies to improve adherence to these drugs among teenage acne patients is warranted.
authors.affiliation: Department of Clinical, Social and Administrative Sciences, College of Pharmacy, University of Michigan, 428 Church Street, CCL Building Office 3571, Ann Arbor, MI 48109, USA. tanxi@umich.edu
authors.forename: Xi
authors.initials: X
authors.lastname: Tan
authors.forename: Amir
authors.initials: A
authors.lastname: Al-Dabagh
authors.forename: Scott A
authors.initials: SA
authors.lastname: Davis
authors.forename: Hsien-Chang
authors.initials: HC
authors.lastname: Lin
authors.forename: Rajesh
authors.initials: R
authors.lastname: Balkrishnan
authors.forename: Jongwha
authors.initials: J
authors.lastname: Chang
authors.forename: Steven R
authors.initials: SR
authors.lastname: Feldman
mesh_terms: D000152:Acne Vulgaris / Q000188:drug therapy*; D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D016015:Logistic Models; D008297:Male; D008484:Medicaid / Q000191:economics / Q000706:statistics & numerical data; D008875:Middle Aged; D012176:Retinoids / Q000627:therapeutic use*; D012189:Retrospective Studies; D014481:United States; D055815:Young Adult; D016903:Drug Monitoring
chemical_list: D000900:Anti-Bacterial Agents; D012176:Retinoids