title: The rate of CD4 decline as a determinant of progression to AIDS independent of the most recent CD4 count. The Italian Seroconversion Study.
abstract: The data of two cohort studies of HIV-infected individuals were used to examine whether the rate of CD4 decline is a determinant of HIV progression, independent of the most recent CD4 count. Time from seroconversion to clinical AIDS was the main outcome measure. Rates of CD4 decline were estimated using the ordinary least squares regression method. AIDS incidences were compared in individuals who had previously experienced either a steeper or a less steep rate of CD4 decline. Cox proportional hazards model including a time-dependent covariate for the rate of CD4 decline was performed. The rate of prior CD4 decline was significantly associated with the risk of developing AIDS independently from the most recent CD4 count, with a 2% increase in hazard of AIDS (P < 0.01) for a difference of 10 cells/mm3 in the estimated yearly drop in CD4 count. This finding gives scientific credit to the belief that individuals with a prior steeper CD4 decline consistently have a higher subsequent risk of developing AIDS than those with a less steep prior decline.
authors.affiliation: Royal Free Centre for HIV Medicine and Department of Primary Care and Population Sciences, Royal Free and University College Medical School, University College London, UK.
authors.forename: A
authors.initials: A
authors.lastname: Cozzi Lepri
authors.forename: C A
authors.initials: CA
authors.lastname: Sabin
authors.forename: A N
authors.initials: AN
authors.lastname: Phillips
authors.forename: C A
authors.initials: CA
authors.lastname: Lee
authors.forename: P
authors.initials: P
authors.lastname: Pezzotti
authors.forename: G
authors.initials: G
authors.lastname: Rezza
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D018791:CD4 Lymphocyte Count; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D015658:HIV Infections / Q000276:immunology; D006679:HIV Seropositivity / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012307:Risk Factors