Document 0388
 DOCN  M9440388
 TI    Tracking of markers and onset of disease among HIV-1 seroconverters.
 DT    9404
 AU    Galai N; Munoz A; Chen K; Carey VJ; Chmiel J; Zhou SY; Department of
       Epidemiology, Johns Hopkins School of Hygiene and; Public Health,
       Baltimore, MD 21205.
 SO    Stat Med. 1993 Nov 30;12(22):2133-45. Unique Identifier : AIDSLINE
       MED/94143616
 AB    Repeated measurements on persons infected with HIV-1 indicate that
       infection has a dynamic impact on several markers of immune suppression
       and activation. The objectives of this report are: (a) to provide a
       statistical model for the correlation structure of serial measurements
       of immunological markers, and (b) to identify features of marker
       profiles associated with the timing of AIDS diagnoses. We analyse data
       obtained from 328 seroconverters participating in the Multicenter AIDS
       Cohort Study on whom the date of HIV-1 seroconversion is known within
       +/- 4.5 months. Immunological markers considered here are CD4 cell
       counts, serum beta 2-microglobulin and serum neopterin. The statistical
       model for HIV-related changes in markers consists of (1) a piecewise
       linear regression model for the trajectories of markers over time and
       (2) a two-parameter autocorrelation function that generalizes Markovian
       and simple random effects autocorrelation structures. Application of
       this model for marker measurements revealed a high degree of tracking,
       as the estimated autocorrelation function exhibited sub-exponential
       decay over time. Though current marker levels are most informative on
       future values, there is substantial information (memory) in previous
       measurements. A feature suggested by the analysis of groups formed
       according to the length of the AIDS-free period, is the sequential
       divergence of the CD4 trajectories where steeper declines occurred with
       a two-year lag prior to AIDS onset. For AIDS cases diagnosed 3-5 and 5-7
       years after seroconversion, the rates of decline compared with those
       free of AIDS for at least 4 years were steeper by 95 and 46 per cent
       respectively at two years prior to AIDS.
 DE    beta 2-Microglobulin/*ANALYSIS  Acquired Immunodeficiency
       Syndrome/*DIAGNOSIS/IMMUNOLOGY  Biopterin/*ANALOGS & DERIVATIVES/BLOOD
       Bisexuality  Cohort Studies  Follow-Up Studies  Homosexuality  Human
       HIV Seropositivity/*DIAGNOSIS/IMMUNOLOGY  *HIV-1/IMMUNOLOGY  *Leukocyte
       Count  Male  Models, Statistical  Monitoring, Immunologic/*METHODS
       Support, U.S. Gov't, P.H.S.  T4 Lymphocytes/*IMMUNOLOGY  JOURNAL ARTICLE
       MULTICENTER STUDY

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).