[Value of HIV-1 viral load and CD4 lymphocyte count as determinants of progression to AIDS and survival].
BACKGROUND
HIV-1 viral load is regarded as a better surrogate marker for progression and death than CD4+ cell counts. Both markers are analysed in a cohort of patients with unknown seroconversion date and advanced HIV infection.


METHODS
Retrospective cohort analysis of 421 patients, most on antiretroviral therapy, with a median initial CD4+ cell count of 209 x 10(6)/l and a median initial viral load of 4.7 log copies/ml. One thousand two hundred and eighty-six samples were analysed. Univariate and bivariate analysis were performed with initial and sequential CD4+ cell counts and viral load values to estimate the risk of progression and death by Cox regression models.


RESULTS
After a median follow up of 763 days, 124 patients developed AIDS and 117 died. Relative risks of progression related to the group that maintained viral load values always < 35,000 copies/ml were: 5-fold (95% CI: 1.4-17.0; p < 0.05) for patients with any viral load value > 35,000 copies/ml but always < 200,000 copies/ml; and 13.6 fold (95% CI: 5.4-34.2; p < 0.0001) for patients who could not maintain viral load < 200.000 copies/ml. CD4+ counts = 100 x 10(6)/l and viral load = 220,000 copies/ml were the threshold values that best fitted to estimate the probability of survival by a bivariate analysis.


CONCLUSIONS
The maintenance of sequential viral load values < 35.000 copies/ml is associated with a lower risk of progression. The maintenance of sequential viral load values < 150,000 copies/ml is associated with higher short-term survival rates.
Romeu
J
J
Hospital de Día VIH (Servicio de Medicina Interna, Badalona, Barcelona.
Balagué
M
M
Ruiz
L
L
Marfil
S
S
Puig
T
T
Arnó
A
A
Veny
A
A
Tural
C
C
Sirera
G
G
Clotet
B
B
D000163:Acquired Immunodeficiency Syndrome / Q000401:mortality / Q000503:physiopathology; D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use; D018791:CD4 Lymphocyte Count; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000188:drug therapy / Q000401:mortality / Q000503:physiopathology*; D015497:HIV-1; D006801:Humans; D008297:Male; D012044:Regression Analysis; D012189:Retrospective Studies; D015996:Survival Rate; D019562:Viral Load
D019380:Anti-HIV Agents