ICTM logo
Temporal trends in postseroconversion CD4 cell count and HIV viral load

08 February 2007

CASCADE is a network of epidemiologists, statisticians, virologists and clinicians from lead HIV institutions in 15 European countries, Australia and Canada. CASCADE’s main aim is to monitor individuals newly infected with HIV and those already enrolled in studies, covering the entire duration of HIV infection.

Their latest results on temporal trends in postseroconversion CD4 cell count and HIV load have been published in the February edition of the Journal of Infectious Diseases.

The authors looked at individuals seroconverting between 1985 and 2002 to determine whether early postseroconversion CD4 cell counts and HIV loads have changed over time. They focused on individuals who had the first CD4 cell count (n=3687) or HIV load (n=1584) measured within 2 years of seroconversion and before antiretroviral use.

They found that the CD4 cell count following seroconversion decreased by an average of 6.33 cells/ mu L per year of seroconversion (95% confidence interval [CI], -8.47 to -4.20 cells/ mu L/year; P<.001), and HIV load increased by 0.044 log(10) copies/mL per year (95% CI, +0.034 to +0.053 log(10) copies/mL/year).

The probability of progressing to a CD4 cell count of <500 cells/ mu L by 24 months from seroconversion increased from 0.66 (95% CI, 0.63-0.69) for individuals who seroconverted before 1991 to 0.80 (95% CI, 0.75-0.84) for those who seroconverted during 1999-2002.

The authors concluded "these data suggest that, in Europe, there has been a trend of decrease in the early CD4 cell count and of increase in the early HIV load. Additional research will be necessary to determine whether similar trends exist in other geographical areas."

Reference: Dorrucci M, Rezza G, Porter K, Phillips A, Concerted Action on Seroconversion to AIDS and Death in Europe Collaboration. Temporal Trends in Postseroconversion CD4 Cell Count and HIV Load: The Concerted Action on Seroconversion to AIDS and Death in Europe Collaboration, 1985-2002. J Infect Dis. 2007 Feb 15;195(4):525-34.