title: Zidovudine and stavudine sequencing in HIV treatment planning: findings from the CHORUS HIV cohort.
abstract: BACKGROUND
  Optimal sequencing of zidovudine and stavudine in antiretroviral therapy has not been elucidated.
  
  
  OBJECTIVE
  To examine the impact of the sequence of therapeutic regimens containing zidovudine and stavudine on HIV-1 RNA and CD4 lymphocyte counts over 12 months.
  
  
  METHODS
  Observational, multicenter, longitudinal cohort study.
  
  
  METHODS
  Four large outpatient, HIV practices participating in the community-based Collaborations in HIV Outcomes Research-U.S. (CHORUS) cohort study.
  
  
  METHODS
  940 HIV-infected patients.
  
  
  METHODS
  Comparison of HIV-1 RNA and CD4 lymphocyte responses in patients sequenced from zidovudine to stavudine or from stavudine to zidovudine using repeated measures regression models fit to outcomes by application of generalized estimating equation (GEE) methodology.
  
  
  RESULTS
  Patients treated with zidovudine prior to stavudine (n = 834) achieved a greater mean drop from baseline HIV-1 RNA (p = .01) and higher proportion of undetectable HIV-1 RNA results (p = .05) over 12 months than those sequenced from stavudine to zidovudine (n = 106). CD4+ lymphocyte increases did not differ between the groups (p = .6).
  
  
  CONCLUSIONS
  Prior zidovudine therapy was not associated with long-term attenuation of HIV-1 RNA or CD4 response to subsequent stavudine-containing regimens. Zidovudine before stavudine may have benefit in a strategic long-term therapeutic plan.
authors.affiliation: Pacific Horizon Medical Group, San Francisco, California 94115, USA. SLBecker@mindspring.com
authors.forename: S L
authors.initials: SL
authors.lastname: Becker
authors.forename: S R
authors.initials: SR
authors.lastname: Raffanti
authors.forename: N I
authors.initials: NI
authors.lastname: Hansen
authors.forename: J S
authors.initials: JS
authors.lastname: Fusco
authors.forename: G P
authors.initials: GP
authors.lastname: Fusco
authors.forename: G H
authors.initials: GH
authors.lastname: Slatko
authors.forename: E F
authors.initials: EF
authors.lastname: Igboko
authors.forename: N M
authors.initials: NM
authors.lastname: Graham
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019380:Anti-HIV Agents / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D018791:CD4 Lymphocyte Count; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology / Q000821:virology; D015497:HIV-1 / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D006716:Homosexuality; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral / Q000032:analysis / Q000235:genetics; D018894:Reverse Transcriptase Inhibitors / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D018119:Stavudine / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D013936:Thymidine / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000627:therapeutic use; D044465:White People; D015215:Zidovudine / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D019380:Anti-HIV Agents; D012367:RNA, Viral; D018894:Reverse Transcriptase Inhibitors; D015215:Zidovudine; D018119:Stavudine; D013936:Thymidine