Study of antiretroviral mutants in HIV patients with treatment failures and the effect of risk factors in the virological failures

Determinants of Virologic Failure among Adult HIV Patients on First-Line Antiretroviral Therapy at Waghimra Zone, Northern Ethiopia: A Case-Control Study

Introduction. The primary goal of antiretroviral therapy (ART) is to reduce the viral load in HIV-infected patients to promote quality of life, as well as to reduce HIV-related morbidity and mortality. A high rate of virologic failure was reported in Waghimra Zone, Northwest Ethiopia, in viral load assessment conducted among HIV-infected patients on ART in the Amhara region. However, there is limited evidence on the determinants of virological failure in the study area. This study aimed to identify the determinants of virological failure among HIV-infected patients on antiretroviral therapy in Waghimra zone, Northern Ethiopia, 2019. Methods. An institutional-based unmatched case-control study was conducted from May 21 to June 30, 2019. Cases were people living with HIV (PLHIV) on ART who had already experienced virological failure; controls were those without virological failure. Data were extracted from 92 cases and 184 controls through chart review using a pretested and structured checklist. The data were entered using Epi Info version 7 and exported to SPSS version 20 for analysis. A multivariate logistic regression analysis was carried out to identify factors associated with virological failure, and variables with a P value <0.05 were considered statistically significant. Results. This study revealed that poor adherence to ART (adjusted odds ratio (AOR) = 4.24, 95% confidence interval (CI): 2.17, 8.31), taking ART for longer than five years (AOR = 3.11, 95% CI: 1.17, 8.25), having drug toxicity (AOR = 3.34, 95% CI: 1.54, 7.23), age of PLHIV ≥ 35 years (AOR = 2.45, 95% CI: 1.29,4.64), and recent CD4 count <200 cells/mm³ (AOR = 3.06, 95% CI: 1.52, 6.13) were factors associated with virologic failure. Conclusion and Recommendation. This study showed that poor adherence to treatment, longer duration on ART, experiencing drug toxicity, older age, and recent CD4 <200 cell/mm³ are factors that increase the risk of virologic failure.

Factors associated with virological failure in a cohort of combination antiretroviral therapy-treated patients managed at a tertiary referral centre

BACKGROUND

Recent antiretroviral regimens are potent and better tolerated, resulting in a low prevalence of treatment failure. It is important to identify the drivers of virological failure, so that patients at risk can be identified early and prevention strategies implemented.

METHODS

We performed a retrospective case-control study of HIV-positive patients on antiretroviral therapy and managed at The Alfred Hospital during 2010 to evaluate the predictors of virological failure. Controls were matched 3:1 to cases by gender, and by clinical review in the same week as the diagnosis of virological failure in the case. Predictors of virological failure were identified by multivariate conditional logistic regression.

RESULTS

Thirty-nine patients were identified with treatment failure. In the multivariate model, characteristics associated with virological failure were missed clinic appointments in 1 year before virological failure (odds ratio (OR)=13.1, 95% confidence interval (CI): 2.8-61.1), multiple previous combined antiretroviral therapy regimens (OR =4.2, 95% CI:1.2-15.3), current hepatitis C infection (OR=8.6, 95% CI: 1.9-38.7), older age at HIV diagnosis (OR=1.1, 95% CI: 1.0-1.2), younger age at time of virological failure (OR=0.9, 95% CI: 0.8 to 1.0), and CD4 cell count at virological failure (OR=0.7, 95% CI: 0.5 to 0.9).

CONCLUSIONS

Targeted and appropriate adherence support should be provided to treatment-experienced patients, particularly those who have missed clinical appointments and those with hepatitis C coinfection. Further elucidation of the barriers to clinic attendance may optimise linkage and retention in care.