title: Comparison of prognostic importance of latest CD4+ cell count and HIV RNA levels in patients with advanced HIV infection on highly active antiretroviral therapy.
abstract: The comparative prognostic importance of latest plasma HIV RNA levels (viral loads) and CD4+ cell counts among patients prescribed highly active antiretroviral therapy (HAART) has not been well characterized.
  
  
  METHODS
  We assessed the prognostic value of latest CD4+ cell counts and latest viral loads for progression to AIDS or death and explored their interaction among 432 HIV-infected persons with advanced HIV who were prescribed a protease inhibitor (PI) as their first HAART regimen.
  
  
  RESULTS
  Pre-HAART median CD4+ cell count and viral load were 41 cells/mm3 and 126,331 copies/mL, respectively. After 12 months of HAART, the median CD4+ cell count was 154 cells/mm3; 39% of patients had a viral load of 400 copies/mL or lower. Over a median follow-up of 33 months, 109 (25%) of the 432 patients experienced an AIDS event or died. The hazard ratio for AIDS or death for those with latest CD4+ cell count <50 cells/mm3 versus > or =200 cells/mm3 was 13.9 (95% CI 6.5 to 29.7) without adjustment for latest viral load measurements and 9.5 (95% CI 4.0 to 22.5) after adjustment for latest viral load. In contrast, the hazard ratio for AIDS or death for those with viral load > or =100,000 versus <400 copies/mL was 4.2 (95% CI 2.3 to 7.7) without adjustment for latest CD4+ level and 1.2 (95% CI 0.6 to 2.4) with adjustment for latest CD4+ cell count.
  
  
  CONCLUSIONS
  We conclude that when latest CD4+ cell count and viral load are considered separately, both are significantly related to AIDS or death; when these markers are jointly considered, the association of viral load with AIDS or death is substantially diminished. Latest CD4+ levels are more strongly related to AIDS or death than latest viral load levels in patients on HAART.
authors.affiliation: Wayne State University, University Health Center, Detroit, Michigan 48201, USA. rmacarthur@med.wayne.edu
authors.forename: Rodger D
authors.initials: RD
authors.lastname: MacArthur
authors.forename: George
authors.initials: G
authors.lastname: Perez
authors.forename: Sharon
authors.initials: S
authors.lastname: Walmsley
authors.forename: John D
authors.initials: JD
authors.lastname: Baxter
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Mullin
authors.forename: James D
authors.initials: JD
authors.lastname: Neaton
mesh_terms: D000328:Adult; D023241:Antiretroviral Therapy, Highly Active; D018791:CD4 Lymphocyte Count; D018450:Disease Progression; D005260:Female; D006678:HIV / Q000235:genetics*; D015658:HIV Infections / Q000188:drug therapy / Q000276:immunology* / Q000821:virology; D017320:HIV Protease Inhibitors / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012367:RNA, Viral / Q000097:blood*
chemical_list: D017320:HIV Protease Inhibitors; D012367:RNA, Viral