OBJECTIVE: To identify the optimal CD4 cell count at which cART should be initiated.
DESIGN: Prospective observational data from the HIV-CAUSAL Collaboration and dynamic marginal structural models were used to compare cART initiation strategies for CD4 thresholds between 0.200 and 0.500 × 10(9) cells/L.
SETTING: HIV clinics in Europe and the Veterans Health Administration system in the United States.
PATIENTS: 20, 971 HIV-infected, therapy-naive persons with baseline CD4 cell counts at or above 0.500 × 10(9) cells/L and no previous AIDS-defining illnesses, of whom 8392 had a CD4 cell count that decreased into the range of 0.200 to 0.499 × 10(9) cells/L and were included in the analysis.
MEASUREMENTS: Hazard ratios and survival proportions for all-cause mortality and a combined end point of AIDS-defining illness or death.
RESULTS: Compared with initiating cART at the CD4 cell count threshold of 0.500 × 10(9) cells/L, the mortality hazard ratio was 1.01 (95% CI, 0.84 to 1.22) for the 0.350 threshold and 1.20 (CI, 0.97 to 1.48) for the 0.200 threshold. The corresponding hazard ratios were 1.38 (CI, 1.23 to 1.56) and 1.90 (CI, 1.67 to 2.15), respectively, for the combined end point of AIDS-defining illness or death.
LIMITATIONS: CD4 cell count at cART initiation was not randomized. Residual confounding may exist.
CONCLUSION: Initiation of cART at a threshold CD4 count of 0.500 × 10(9) cells/L increases AIDS-free survival. However, mortality did not vary substantially with the use of CD4 thresholds between 0.300 and 0.500 × 10(9) cells/L.
METHODS: Factors associated with survival and failure were analyzed using Cox proportional hazards and discrete time conditional logistic models.
RESULTS: TDR, found in 60 (4.1%) of 1471 Asian treatment-naive patients, was one of the significant predictors of failure. Patients with TDR to >1 drug in their regimen were >3 times as likely to fail compared to no TDR.
CONCLUSIONS: TDR was associated with failure in the context of non-fully sensitive regimens. Efforts are needed to incorporate resistance testing into national treatment programs.
METHODS: HIV-positive patients enrolled in the TREAT Asia HIV Observational Database who had used second-line ART for ≥6 months were included. ART use and rates and predictors of second-line treatment failure were evaluated.
RESULTS: There were 302 eligible patients. Most were male (76.5%) and exposed to HIV via heterosexual contact (71.5%). Median age at second-line initiation was 39.2 years, median CD4 cell count was 146 cells per cubic millimeter, and median HIV viral load was 16,224 copies per milliliter. Patients started second-line ART before 2007 (n = 105), 2007-2010 (n = 147) and after 2010 (n = 50). Ritonavir-boosted lopinavir and atazanavir accounted for the majority of protease inhibitor use after 2006. Median follow-up time on second-line therapy was 2.3 years. The rates of treatment failure and mortality per 100 patient/years were 8.8 (95% confidence interval: 7.1 to 10.9) and 1.1 (95% confidence interval: 0.6 to 1.9), respectively. Older age, high baseline viral load, and use of a protease inhibitor other than lopinavir or atazanavir were associated with a significantly shorter time to second-line failure.
CONCLUSIONS: Increased access to viral load monitoring to facilitate early detection of first-line ART failure and subsequent treatment switch is important for maximizing the durability of second-line therapy in Asia. Although second-line ART is highly effective in the region, the reported rate of failure emphasizes the need for third-line ART in a small portion of patients.
METHODS: Children enrolled in the TREAT Asia Pediatric HIV Observational Database who had SM (weight-for-height or body mass index-for-age Z score less than -3) at ART initiation were analyzed. Generalized estimating equations were used to investigate poor weight recovery (weight-for-age Z score less than -3) and poor CD4% recovery (CD4% <25), and competing risk regression was used to analyze mortality and toxicity-associated treatment modification.
RESULTS: Three hundred fifty-five (11.9%) of 2993 children starting ART had SM. Their median weight-for-age Z score increased from -5.6 at ART initiation to -2.3 after 36 months. Not using trimethoprim-sulfamethoxazole prophylaxis at baseline was associated with poor weight recovery [odds ratio: 2.49 vs. using; 95% confidence interval (CI): 1.66-3.74; P < 0.001]. Median CD4% increased from 3.0 at ART initiation to 27.2 after 36 months, and 56 (15.3%) children died during follow-up. More profound SM was associated with poor CD4% recovery (odds ratio: 1.78 for Z score less than -4.5 vs. -3.5 to less than -3.0; 95% CI: 1.08-2.92; P = 0.023) and mortality (hazard ratio: 2.57 for Z score less than -4.5 vs. -3.5 to less than -3.0; 95% CI: 1.24-5.33; P = 0.011). Twenty-two toxicity-associated ART modifications occurred at a rate of 2.4 per 100 patient-years, and rates did not differ by malnutrition severity.
CONCLUSION: Trimethoprim-sulfamethoxazole prophylaxis is important for the recovery of weight-for-age in severely malnourished children starting ART. The extent of SM does not impede weight-for-age recovery or antiretroviral tolerability, but CD4% response is compromised in children with a very low weight-for-height/body mass index-for-age Z score, which may contribute to their high rate of mortality.