Assessment of HIV viral load monitoring in remote settings in Vietnam - comparing people who inject drugs to the other patients

Introduction: Increasing access to viral load (VL) monitoring is essential to fight HIV epidemics. In remote settings in Vietnam, using dried blood spot (DBS) sampling for specimen collection could improve the situation. Here, people who inject drugs (PWID) represent many newly antiretroviral therapy (ART)-initiated patients. The goals of this evaluation were to evaluate if access to VL monitoring and the rate of virological failure differed between PWID and non-PWID. Methods: Prospective cohort study of patients newly initiated on ART in remote settings in Vietnam. DBS coverage at 6, 12 and 24 months of ART was investigated. Factors associated with DBS coverage were identified through logistic regression, as were factors associated with virological failure (VL ≥1,000 copies/mL) at 6, 12 and 24 months of ART. Results: Overall 578 patients were enrolled in the cohort, of whom 261 (45%) were PWID. DBS coverage improved from 74.7% to 82.9% between 6 and 24 months of ART (p = 0.001). PWID status was not associated with DBS coverage (p = 0.74), but DBS coverage was lower in patients who were late to clinical visits and in those in WHO stage 4 (p = 0.023 and p = 0.001, respectively). The virological failure rate decreased from 15.8% to 6.6% between 6 and 24 months of ART (p