title: Survival benefit of initiating antiretroviral therapy in HIV-infected persons in different CD4+ cell strata.
abstract: BACKGROUND
  Optimal timing of antiretroviral therapy (ART) initiation for HIV-infected persons remains unclear.
  
  
  OBJECTIVE
  To assess survival benefit of initiating ART at different CD4+ cell counts.
  
  
  METHODS
  Prospective observational study.
  
  
  METHODS
  U.S. clinics in the HIV Outpatient Study (HOPS).
  
  
  METHODS
  HIV-infected patients with CD4+ cell counts, plasma HIV RNA viral load, and ART use recorded from January 1994 through March 2002.
  
  
  METHODS
  Before initiation of ART, patients were grouped by their CD4+ cell counts into three subgroups: 0.201 to 0.350 x 10(9) cells/L (n = 399), 0.351 to 0.500 x 10(9) cells/L (n = 327), and 0.501 to 0.750 x 10(9) cells/L (n = 122). We compared mortality rates for each CD4+ subgroup among patients who initiated ART and patients who delayed ART until reaching a lower CD4+ subgroup.
  
  
  RESULTS
  Mortality rates for 340 patients who initiated ART and 59 who delayed ART in the CD4+ subgroup of 0.201 to 0.350 x 10(9) cells/L were 15.4 and 56.4 deaths per 1000 person-years, respectively (rate ratio, 0.27 [95% CI, 0.14 to 0.55]; P < 0.001). For the CD4+ subgroup of 0.351 to 0.500 x 10(9) cells/L, mortality rates for 240 patients who initiated ART and 887 who delayed ART were 10.0 and 16.6 deaths per 1000 person-years, respectively (rate ratio, 0.61 [CI, 0.22 to 1.67]; P = 0.17). For the CD4+ subgroup of 0.501 to 0.750 x 10(9) cells/L, mortality rates in 55 patients who initiated ART and 67 who delayed ART were 7.5 and 3.1 deaths per 1000 person-years, respectively (rate ratio, 1.20 [CI, 0.17 to 8.53]; P > 0.2). Patients in the 0.201 to 0.350 x 10(9) cells/L and 0.351 to 0.500 x 10(9) cells/L CD4+ subgroups who initiated ART were more likely than those who delayed ART to achieve an undetectable HIV viral load (P = 0.03 and 0.04, respectively).
  
  
  CONCLUSIONS
  Among HIV-infected persons with CD4+ cell counts of 0.201 to 0.350 x 10(9) cells/L, initiating ART is associated with reduced mortality compared with delaying such therapy. Survival benefits of earlier ART initiation (at CD4+ cell counts of 0.351 to 0.500 x 10(9) cells/L) are possible.
authors.affiliation: Division of Infectious Diseases, The Feinberg School of Medicine, Northwestern University, 676 North Saint Clair, Suite 200, Chicago, Illinois 60611, USA. f-palella@northwestern.edu
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Palella
authors.forename: Maria
authors.initials: M
authors.lastname: Deloria-Knoll
authors.forename: Joan S
authors.initials: JS
authors.lastname: Chmiel
authors.forename: Anne C
authors.initials: AC
authors.lastname: Moorman
authors.forename: Kathleen C
authors.initials: KC
authors.lastname: Wood
authors.forename: Alan E
authors.initials: AE
authors.lastname: Greenberg
authors.forename: Scott D
authors.initials: SD
authors.lastname: Holmberg
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage*; D023241:Antiretroviral Therapy, Highly Active / Q000379:methods; D018791:CD4 Lymphocyte Count; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology / Q000401:mortality* / Q000821:virology; D006801:Humans; D008297:Male; D016016:Proportional Hazards Models; D011446:Prospective Studies; D015996:Survival Rate; D019562:Viral Load
chemical_list: D019380:Anti-HIV Agents