HIV-1 CRF01_AE subtype and HIV-1 DNA level among patients with chronic HIV-1 infection: a correlation study.

Background: The impact of HIV-1 subtype (CRF01_AE and non-CRF01_AE) on HIV-1 DNA levels in HIV-1 chronically infected patients with suppressive antiretroviral therapy (ART) remains poorly understood. To evaluate the correlation of HIV-1 subtype with DNA level, and identify baseline predictors of HIV-1 DNA decay.
Methods: ART-naïve HIV-1-infected patients from two large multi-center studies in China were classified into CRF01_AE and non-CRF01_AE subtype groups. Peripheral blood samples were collected at baseline and week 12, 24, 48 and 96 after ART initiation and total HIV-1 DNA levels were quantified by real-time PCR. HIV-1 DNA levels at week 96 were categorized into high, moderate, and low levels, reflecting HIV-1 DNA ≥ 3, 2-3, ≤ 2 log ₁₀ copies/10 ⁶ PBMCs, respectively, and the corresponding proportion of CRF01_AE and non-CRF01_AE subtype were compared. The baseline predictors of low HIV-1 total DNA levels (≤ 2 log ₁₀ copies/10 ⁶ PBMCs) at week 96 were evaluated using a logistic regression model.
Results: Compared to the non-CRF01&#95;AE subtypes (n = 185), patients with CRF01&#95;AE subtype (n = 188) harboured a higher level of HIV-1 DNA (median: 3.19 vs. 2.95 log ₁₀ copies/10 ⁶ PBMCs, P < 0.001) prior to treatment. After 96 weeks of ART, HIV-1 DNA levels remained higher in the CRF01&#95;AE subtype group (median: 2.63 vs. 2.39 log ₁₀ copies/10 ⁶ PBMCs, P = 0.002). There was no significant difference in the proportion of patients achieving high (22.3% vs. 14.6%, P = 0.054), moderate (59.6% vs. 60.5%, P = 0.849) and low levels (18.1% vs 24.9%, P = 0.111) between CRF01&#95;AE and non-CRF01&#95;AE groups. In the multivariable analysis, baseline HIV-1 DNA level and CD4 ⁺ T cell count but not the subtype were independent risk factors for achieving HIV-1 DNA level ≤ 2 log ₁₀ copies/10 ⁶ PBMCs.
Conclusion: HIV-1 CRF01&#95;AE subtype is neither correlated with HIV-1 DNA reservoir decline nor a prognostic factor for achieving lower HIV-1 DNA levels (≤ 2 log ₁₀ copies/10 ⁶ PBMCs) after ART. However, higher HIV-1 DNA level in HIV-1 CRF01&#95;AE patients should be aroused much attention and strengthen surveillance during ART.