Determinants of viral load suppression failure among HIV adults on ARV attending health care facilities: a retrospective study in Tanga region, Tanzania.

Background: Availability and accessibility of Antiretroviral drugs (ARV's) improve the lives of People living with HIV (PLHIV) by improving client's immune system to overcome infections and prevent the development of AIDS and other HIV complications. Combination therapy, early initiation of ART, newer ART drugs, single dosage and drug affordability significantly contribute in the reduction of viral multiplication and suppression of HIV to undetectable plasma levels.

Methods: A retrospective longitudinal study design study was conducted from 1 October, 2018 to 30 June 2022 in all supported HIV care and treatment health facilities in Tanga region which were supported by Amref Health Africa, Tanzania. The participants were HIV adult patients aged 15 years and above on ART and attended the clinic at least once after ART initiation. Viral load suppression levels are defined with viral load <1,000 HIV RNA copies/ml (viral load suppression). Cox proportional hazard regression models were employed to identify risk factors for virological failure. P values were two-sided, and we considered a P<0.05 to be statistically significant.

Results: Fifty-nine thousand five hundred three adult clients >15 years whom were on ART were included in the analysis to determine the level of plasma Viral Load suppression after being on ART. Female 41,304 (69.4%) and male 18,199 (30.6%). Only four percent (2,290) were found to be unsuppressed i.e having plasma Viral Load >1,000cp/ml while 96% (57,213) were virally suppressed. Several factors were independently associated with virologic failure that included; age between 15 - <25 years (HR: 2.82, 95% CI 1.96 - 4.04), BMI <18.5 (HR: 1.69, 95% CI 1.23 - 2.30), advanced WHO stage IV (HR: 1.60, 95% CI 1.12 - 2.24), CD4 cell count <350 (HR: 2.61, 95% CI 2.12 - 3.23), poor adherence (HR: 1.98, 95% CI 1.80 - 2.18) and not using DTG based drug (HR: 11.8, 95% CI 9.74 - 14.3).

Conclusion: Virologic failure was observed in this study among clients with young age, advanced WHO stage IV, not using DTG based regimen, poor drug adherence and second line regime. To improve Viral Load Suppression among these clients; the existing HIV intervention strategies should be taken care by targeting the identified risk factors.