Predictors of failure on second-line antiretroviral therapy with protease inhibitor mutations in Uganda

Failure on second-line antiretroviral therapy (ART) with protease inhibitor (PI) mutations (VF-M) is on the rise. However, there is a paucity of information on the factors associated with this observation in low-income countries. Knowledge of underlying factors is critical if we are to minimize the number of PLHIV switched to costly third-line ART. Our study investigated the factors associated with VF-M.

We conducted a matched case-control analysis of patients' records kept at the Joint Clinical Research Center, starting from January 2008 to May 2018. We matched records of patients who failed the second-line ART with major PI mutations (cases) with records of patients who were virologically suppressed (controls) by a ratio of 1:3. Data analysis was conducted using STATA Version 14. Categorical variables were compared with the outcomes failure on second-line ART with PI mutations using the Chi-square and Fisher's exact tests where appropriate. Conditional logistic regression for paired data was used to assess the association between the outcome and exposure variables, employing the backward model building procedure.

Of the 340 reviewed patients' records, 53% were women, and 6.2% had previous tuberculosis treatment. Males (aOR = 2.58, [CI 1.42-4.69]), and patients concurrently on tuberculosis treatment while on second-line ART (aOR = 5.65, [CI 1.76-18.09]) had higher odds of VF-M. ART initiation between 2001 and 2015 had lower odds of VF-M relative to initiation before the year 2001.

Males and patients concomitantly on tuberculosis treatment while on second-line ART are at a higher risk of VF-M. HIV/AIDS response programs should give special attention to this group of people if we are to minimize the need for expensive third-line ART. We recommend more extensive, explorative studies to ascertain underlying factors.