Determinants of mortality and survival time among HIV infected patients on antiretroviral therapy in Machakos county, Kenya

Abstract

ABSTRACT Human Immunodeficiency Virus (HIV) remains one of the world's most significant public health concerns. Anti-retroviral treatment (ART) is meant to suppress replication of the virus, consequently improving health outcomes by improving immunity and delaying mortality. Despite policy interventions expanding antiretroviral treatment (ART) services rendering their provision in Kenyan public health facilities free, there exists limited data on survival outcomes in the ART program. Machakos having been listed as a medium epidemic county with no data on ART survival outcomes, it is worthwhile undertaking this study in the area. The aim of this study was to estimate survival time and identify survival predictors of patients on ART using data obtained from government hospitals drawn from five sub-counties in Machakos County. Records of 5,393 adult and paediatric patients initiating ART between January 2011 to December 31, 2015 were included in the retrospective cohort study. Kaplan-Meier methods were used to assess survival probabilities and patterns of HIV-infected patients receiving antiretroviral treatment and log rank tests to compare survival distributions. The Cox-proportional hazard model was used to identify predictors of mortality among ART taking HIV infected patients. The median survival time among ART receiving HIV infected patients was 55 months (95% CI: 51.046-59.986) months with 932 (17.3%) patients having died during the study period. Females exhibited better survival than the males 58months (95% CI: 51.790-59.546) vs. 48 months (95%CI=44.398-53.479) while young adults aged between 20 to 24 years registered lower survival time of 24 months(95%CI: 21.654-28.140). The most important determinants of survival at 5% significance were patients receiving ART in Machakos, patients aged between 20 to 24 years, BMI of less than 18.5, TB infection, advanced disease progression at initiation of therapy (WHO stage 4 ) and CD4 count less than 100 gm/ul. Based on the findings, it can be concluded that interventions around monitoring of patients receiving treatment in Machakos sub-county, aged between 20 to 24 years ,exhibiting low CD4 cell counts, advanced WHO stages, confection with TB should be carefully tailored to improve the survival of HIV infected patients. Similar studies in the future need to additionally consider ascertaining the status of the lost to follow up patients prior to undertaking survival analysis of HIV infected patients on antiretroviral.