Increased risk of virological failure to the first antiretroviral regimen in HIV-infected migrants compared to natives: data from the ICONA cohort.

Introduction: Aim of the study was to evaluate possible disparities in access and/or risk of virological failure (VF) to the first antiretroviral (ART) regimen for migrants compared to Italian-born patients and to assess determinants of failure for the migrants living with HIV.

Methods: All native and migrant naïve patients enrolled in ICONA in 2004-2014 were included. Firstly, variables associated to ART initiation were analyzed. In a second analysis, the primary endpoint was time to failure after at least six months of ART, defined as: (a) VF (first of two consecutive viral load (VL) >50 and >200 copies/mL); (b) treatment discontinuation (TD) for any reason; and (c) treatment failure (TF: confirmed VL >200 cp/mL or TD). A Poisson multivariable analysis was performed to control for confounders.

Results: A total of 5777 HIV-pos ART-naïve patients (1179 migrants and 4598 natives) were evaluated. Most migrants were from sub-Saharan Africa (35.3%) and South-Central America/Caribbean (29%). Median duration of residency in Italy was five years (IQR 1-10). Baseline characteristics significantly differed between the two groups (Table 1); in particular, lower CD4 counts and higher frequency of AIDS events were observed in migrants vs natives. When adjusting for baseline confounders, migrants presented a lower chance to initiate ART compared to natives (OR 0.78, 95% CI 0.65-0.93, p=0.006). After ART initiation, the incidence rate of VF >50 cp/mL was 15.5 per 100 person-years (95% CI 12.8-18.8) in migrants and 8.9 in natives (95% CI 7.9-9.9), respectively. By multivariable analysis, migrants had a significantly higher risk of VF, both >50 cp/mL (OR 1.50, 95% CI 1.17-1.193, p=0.001) and >200 cp/mL (OR 1.59, 95% CI 1.23-2.05, p<0.001), and of TF (OR 1.15, 95% CI 1.00-1.32, p=0.045), while no differences were observed in TD risk. Among migrants, variables associated with a higher VF risk were age (for 10-year increase, OR 0.96, 95% CI 0.93-0.98, p=0.002), unemployment (OR 1.96, 95% CI 1.20-3.20, p=0.007) and use of a boosted PI based-regimen (OR 2.04, 95% CI 1.25-3.34, p=0.005 vs NNRTI-based), while pregnancy was associated with TD (OR 3.73, 95% CI 2.36-5.90, p<0.001) and TF (OR 3.13, 95% CI 02.00-4.89, p<0.001).

Conclusions: Despite the use of more potent and safer antiretroviral drugs in the last 10 years, and even in a setting of universal access to ART, migrants living with HIV still present barriers to ART initiation and increased risk of VF compared to natives.