Treatment failure and associated factors among individuals on second line antiretroviral therapy attending Mbale regional referral hospital :

Abstract

Background: ART failure is a growing public health problem and a major threat to the progress of HIV/AIDS control. In Uganda however, little is documented on treatment outcomes and their associated factors among individuals on second line ART regimen. The rapid scale-up of ART over the past has resulted in substantial reductions in morbidity and mortality. However, as millions of people must be maintained on ART for life, individuals with ART treatment failure are increasingly encountered and the numbers are expected to rise. This could be attributed to factors such as sub-standard regimens, limited access to routine viral load monitoring, treatment interruptions, suboptimal adherence, among others. The purpose of this study was to estimate five-year cumulative treatment failure and the associated factors among individuals on second line ART regimen attending Mbale regional referral hospital. Materials and methods: A retrospective analysis of 541 records of HIV positive individuals, switched to second line ART regimen from Jan 2012 to Dec 2017. Inferential statistics including the Chi square test and multivariable logistic regression analysis was applied to determine associations of treatment failure against of the selected demographic, laboratory and clinical factors was performed. Associations between treatment failure and the predictors was based on a p-value of less than 5% and confidence intervals level of 95%. Results We reviewed 541 records of individuals on second line ART regimen, of which 350 (64.7%) were female, 226 (41.8%) were married, and 197 (36.4%) were older than 35 years. The mean age at ART initiation was 30 years (SD=14. 8), while the mean weight at ART initiation was 47kgs (SD=18.6), (range 4-97 kgs). The overall proportion of treatment failure was 23%. The cumulative mortality risk for five years was 12.4% and the mortality rate was 2.5 deaths per 100 individuals per year. The odds of developing treatment failure among individuals switched to ATV/r-based regimen were 44 % lower as compared to individuals who were switched to LPV/r (ORadj0.56, 95% CI 0.35-0.90, p=0.016). while the odds of experiencing treatment failure among individuals that used AZT at ART initiation were 43% lower as compared to individuals that used a TDF based regimen at ART initiation (ORadj0.57, 95% CI 0.33-0.98, p=0.041). Conclusion: The five year cumulative incidence of treatment failure in a cohort of 541 individuals was 23%. The type of protease inhibitor (PI) used in second line regimen and use of AZT at ART initiation were significantly associated with treatment failure. Our study also shows that the cumulative mortality risk while on second line ART regimen was 12.4% while the mortality rate was 2.5 deaths per 100 individuals per year. Recommendations: The Ministry of Health should consider adopting early resistance testing for persons with viral loads beyond the threshold so as to facilitate early identification of resistance and subsequent regimen switch to higher regimens. According to the 2018 HIV prevention and treatment guidelines, third line ART regimen is only issued at the regional referral hospitals. We recommend that an alternative third-line ART regimen be availed for those individuals in district hospitals who are on a failing second-line regimen given the high level of treatment failure among individuals on 2nd line ART regimen,