Predictive value of viral load and other markers for progression to clinical AIDS after CD4+ cell count falls below 200/microL. SEROCO & HEMOCO Study Group.
BACKGROUND
To assess the predictive value of biological and clinical events for progression to AIDS (1993 European classification) when the CD4+ cell count falls below 200/microL (CD4 threshold) in different exposure groups. To investigate whether such markers remain predictive independently of the serum HIV-1 RNA level at the CD4 threshold.


METHODS
The predictive value of biological and clinical events occurring during the 24 months prior to the occurrence of CD4 threshold (n = 333) was quantified in a Cox model. Another Cox model was carried out in a subset of 77 patients in whom viral load from stored sera was available. Furthermore, changes in viral load during the 24 months preceding the CD4 threshold were assessed in a mixed model according to subsequent development of AIDS.


RESULTS
Among the 333 patients, the slope of the CD4+ cell counts, the emergence of p24 antigen, persistent thrush, and age at the CD4 threshold were independent predictors of progression to clinical AIDS (44.7%). Among the subset of 77 patients, the HIV-1 RNA level at the CD4 threshold, persistent thrush and age remained independent predictors of progression to AIDS (45.5%). The increase of the HIV-1 RNA level was moderate, both in non-progressors (24.0% per year) and in those who subsequently developed AIDS (27.1% per year), (P = 0.93). Viral load was consistently higher in the latter group (P = 0.002).


CONCLUSIONS
At a late stage of infection, age and persistent thrush remain predictive of progression to AIDS, independently of viral load.
Carré
N
N
INSERM U292, Secteur Bleu Pierre-Marié Porte 26, Hôpital de Bicêtre, Le Kremlin-Bicêtre, France.
Boufassa
F
F
Hubert
J B
JB
Chavance
M
M
Rouzioux
C
C
Goujard
C
C
Laurian
Y
Y
Meyer
L
L
D000163:Acquired Immunodeficiency Syndrome / Q000453:epidemiology*; D000328:Adult; D018791:CD4 Lymphocyte Count; D018450:Disease Progression; D005260:Female; D015497:HIV-1 / Q000235:genetics; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012367:RNA, Viral / Q000032:analysis; D019562:Viral Load
D012367:RNA, Viral