Quantitative HIV-1 RNA as a marker of clinical stability and survival in a cohort of 302 patients with a mean CD4 cell count of 300 x 10(6)/l.

Methods: Analysis of progression to AIDS and survival, according to initial and longitudinal viral load (VL) and CD4 cell count measurements was performed by Kaplan-Meier test. Relative risks were calculated by Cox's proportional hazards model.

Results: During a mean follow-up of 444 +/- 309 days, 29 patients developed AIDS and 21 died. Relative risk (RR) of progression related to the group with VL 35,000 was: 10.4 when CD4 > or = 250 x 10(6)/l and VL > or = 35,000 (P = 0.001); and 45.3 when CD4 250 x 10(6)/l and VL > or = 35,000 (P 0.0001). Cumulative probability of progression was: 0%, 0% and 12.3%, at the first, second and third year respectively, for patients with all their sequential VL determinations 60,000; and 13.3%, 34.7% and 79.3% for patients who did not maintain VL values always 60,000 (RR = 23; P 0.0001). The minimum value of VL that reached statistical significance for the survival analysis was 100,000 copies/ml (P 0.0001).

Conclusion: During a mean follow-up of 444 +/- 309 days, 29 patients developed AIDS and 21 died. Relative risk (RR) of progression related to the group with VL 35,000 was: 10.4 when CD4 > or = 250 x 10(6)/l and VL > or = 35,000 (P = 0.001); and 45.3 when CD4 250 x 10(6)/l and VL > or = 35,000 (P 0.0001). Cumulative probability of progression was: 0%, 0% and 12.3%, at the first, second and third year respectively, for patients with all their sequential VL determinations 60,000; and 13.3%, 34.7% and 79.3% for patients who did not maintain VL values always 60,000 (RR = 23; P 0.0001). The minimum value of VL that reached statistical significance for the survival analysis was 100,000 copies/ml (P 0.0001).