title: Should resistance testing be performed for treatment-naive HIV-infected patients? A cost-effectiveness analysis.
abstract: BACKGROUND
  Data from the United States and Europe show a population prevalence of baseline drug resistance of 8%-10% among human immunodeficiency virus (HIV)-infected patients who are antiretroviral naive. Our objective was to determine the clinical impact and cost-effectiveness of genotype resistance testing for treatment-naive patients with chronic HIV infection.
  
  
  METHODS
  We utilized a state-transition model of HIV disease to project life expectancy, costs, and cost-effectiveness in a hypothetical cohort of antiretroviral-naive patients with chronic HIV infection. On the basis of a US survey of treatment-naive patients from the Centers for Disease Control and Prevention, we used a baseline prevalence of drug resistance of 8.3%.
  
  
  RESULTS
  A strategy of genotype-resistance testing at initial diagnosis of HIV infection increased per-person quality-adjusted life expectancy by 1.0 months, with an incremental cost-effectiveness ratio of 23,900 dollars per quality-adjusted life-year gained, compared with no genotype testing. The cost-effectiveness ratio for resistance testing remained less than 50,000 dollars per quality-adjusted life-year gained, unless the prevalence of resistance was < or =1%, a level lower than those reported in most regions of the United States and Europe. In sensitivity analyses, the cost-effectiveness remained favorable through wide variations in baseline assumptions, including variations in genotype cost, prevalence of resistance overall and to individual drug classes, and sensitivity of resistance testing.
  
  
  CONCLUSIONS
  Genotype-resistance testing of chronically HIV-infected, antiretroviral-naive patients is likely to improve clinical outcomes and is cost-effective, compared with other HIV care in the United States. Resistance testing at the time of diagnosis should be the standard of care.
authors.affiliation: Division of Infectious Diseases, Brigham and Women's Hospital, Boston, MA 02115, USA. psax@partners.org
authors.forename: Paul E
authors.initials: PE
authors.lastname: Sax
authors.forename: Runa
authors.initials: R
authors.lastname: Islam
authors.forename: Rochelle P
authors.initials: RP
authors.lastname: Walensky
authors.forename: Elena
authors.initials: E
authors.lastname: Losina
authors.forename: Milton C
authors.initials: MC
authors.lastname: Weinstein
authors.forename: Sue J
authors.initials: SJ
authors.lastname: Goldie
authors.forename: Sara N
authors.initials: SN
authors.lastname: Sadownik
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Freedberg
mesh_terms: D000328:Adult; D044966:Anti-Retroviral Agents / Q000494:pharmacology / Q000627:therapeutic use*; D003362:Cost-Benefit Analysis; D024882:Drug Resistance, Viral; D005260:Female; D005838:Genotype; D006678:HIV / Q000187:drug effects / Q000235:genetics; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests / Q000191:economics* / Q000706:statistics & numerical data*
chemical_list: D044966:Anti-Retroviral Agents