Difference in clinical implications of CD4 counts among HIV-infected homosexual men and injection drug using men and women.
While the relationship between CD4 counts and clinical symptoms is well established among homosexual men, the same is not true for injection drug using men and women (IDUM and IDUW). In this paper we investigate whether CD4 counts have the same clinical implications for IDUM and IDUW as for homosexual men. We estimated the CD4 counts at which 50 per cent of the HIV-infected but AIDS-free population has AIDS related complex (ARC) based on three biannually measured CD4 counts. The analyses involve interval, right and left censored threshold data. We took the parametric approach, assuming that the threshold values for ARC arise from a family of distributions that includes symmetric, left or right skewed distributions, in which the logistic and extreme value distributions are embedded as special cases. The resulting estimates of median thresholds of CD4 counts for ARC were 249, 424 and 755 for homosexual men, IDUM, and IDUW, respectively. The results were robust with respect to the assumptions on the underlying distribution.
Division of Biostatistics, School of Public Health, Columbia University, NY, NY, 10032, USA.
M C
MC
Paik
M D
MD
Begg
W
W
el-Sadr
J
J
Gorman
Z
Z
Stien
D000386:AIDS-Related Complex / Q000276:immunology; D000163:Acquired Immunodeficiency Syndrome / Q000175:diagnosis / Q000276:immunology; D000328:Adult; D018791:CD4 Lymphocyte Count; D016001:Confidence Intervals; D005260:Female; D005500:Follow-Up Studies; D006679:HIV Seropositivity / Q000175:diagnosis / Q000276:immunology*; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D015233:Models, Statistical; D012016:Reference Values; D015819:Substance Abuse, Intravenous / Q000276:immunology*