Resum: |
The strong association of CD4 count at start of combination therapy with subsequent survival in HIV-infected patients diminished during the first 5 years of treatment. After 5 years, lower baseline CD4 counts were not associated with higher mortality. Background. CD4 count at start of combination antiretroviral therapy (ART) is strongly associated with short-term survival, but its association with longer-term survival is less well characterized. Methods. We estimated mortality rates (MRs) by time since start of ART (<0. 5, 0. 5-0. 9, 1-2. 9, 3-4. 9, 5-9. 9, and ≥10 years) among patients from 18 European and North American cohorts who started ART during 1996-2001. Piecewise exponential models stratified by cohort were used to estimate crude and adjusted (for sex, age, transmission risk, period of starting ART [1996-1997, 1998-1999, 2000-2001], and AIDS and human immunodeficiency virus type 1 RNA at baseline) mortality rate ratios (MRRs) by CD4 count at start of ART (0-49, 50-99, 100-199, 200-349, 350-499, ≥500 cells/µL) overall and separately according to time since start of ART. Results. A total of 6344 of 37 496 patients died during 359 219 years of follow-up. The MR per 1000 person-years was 32. 8 (95% confidence interval [CI], 30. 2-35. 5) during the first 6 months, declining to 16. 0 (95% CI, 15. 4-16. 8) during 5-9. 9 years and 14. 2 (95% CI, 13. 3-15. 1) after 10 years' duration of ART. During the first year of ART, there was a strong inverse association of CD4 count at start of ART with mortality. This diminished over the next 4 years. The adjusted MRR per CD4 group was 0. 97 (95% CI,. 94-1. 00; P =. 054) and 1. 02 (95% CI,. 98-1. 07; P =. 32) among patients followed for 5-9. 9 and ≥10 years, respectively. Conclusions. After surviving 5 years of ART, the mortality of patients who started ART with low baseline CD4 count converged with mortality of patients with intermediate and high baseline CD4 counts. |