title: Early or deferred zidovudine therapy in HIV-infected patients without an AIDS-defining illness.
abstract: OBJECTIVE
  To do a meta-analysis on the efficacy of early or deferred zidovudine monotherapy in patients with human immunodeficiency virus (HIV) infection but not the acquired immunodeficiency syndrome (AIDS).
  
  
  METHODS
  Articles on zidovudine monotherapy published through May 1994.
  
  
  METHODS
  Double-blind, randomized, placebo-controlled trials addressing the efficacy of zidovudine monotherapy in HIV-infected persons without an AIDS-defining illness.
  
  
  METHODS
  Progression to any primary trial end point; any clinical end point; and AIDS or death. Data were stratified according to disease stage at study entry and duration of follow-up (short-term, < 14 months; long-term, > 21 months).
  
  
  RESULTS
  Early initiation of zidovudine therapy was of short-term benefit for all the end points evaluated (for example, the risk ratio for progression to any primary end point was 0.51; 95% CI, 0.41 to 0.64). Long-term trials showed a marginally significant trend of decreased progression to any primary end point (risk ratio, 0.73; CI, 0.52 to 1.03). The trend was not significant for other end points. With further stratification according to disease stage, progression to AIDS or death in the short term was significantly decreased for both symptomatic and asymptomatic patients with CD4 cell counts of less than 500 x 10(6)/L (risk ratios, 0.26 [CI, 0.13 to 0.56] and 0.43 [CI, 0.30 to 0.64], respectively). A regression analysis indicated a larger relative benefit in short-term trials and symptomatic patients than in long-term trials and asymptomatic patients.
  
  
  CONCLUSIONS
  Early initiation of zidovudine therapy offers a benefit that decreases over time. Symptomatic patients experience a larger benefit than asymptomatic patients. The implications beyond 3 years of follow-up remain unknown.
authors.affiliation: Tufts University School of Medicine, Boston, Massachusetts, USA.
authors.forename: J P
authors.initials: JP
authors.lastname: Ioannidis
authors.forename: J C
authors.initials: JC
authors.lastname: Cappelleri
authors.forename: J
authors.initials: J
authors.lastname: Lau
authors.forename: P R
authors.initials: PR
authors.lastname: Skolnik
authors.forename: B
authors.initials: B
authors.lastname: Melville
authors.forename: T C
authors.initials: TC
authors.lastname: Chalmers
authors.forename: H S
authors.initials: HS
authors.lastname: Sacks
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000188:drug therapy; D018450:Disease Progression; D015658:HIV Infections / Q000188:drug therapy* / Q000401:mortality; D006801:Humans; D016017:Odds Ratio; D016032:Randomized Controlled Trials as Topic; D012044:Regression Analysis; D013997:Time Factors; D015215:Zidovudine / Q000627:therapeutic use*
chemical_list: D015215:Zidovudine