Modelling Time to Hypertension Development and Associated Factors Among Patients on First Line Anti Retroviral Therapy in Kenyatta National Hospital

Abstract

INTRODUCTION: Kenya is among Sub Saharan African countries facing the HIV/AIDS epidemic challenge. The introduction of ART in management of this epidemic has yielded good results in terms of viral suppression, reduction on opportunistic infections and boosting the immune system. However, there has been an increased incidence of non-communicable diseases and among them hypertension has been a key factor leading to mortality in these patients. Persons initiated on ART frequently develop hypertension but the duration patients take after being initiated on ART treatment to get hypertension and the factors that may lead to some patients becoming hypertensive earlier than others regardless of being put on same treatment remain incompletely explained. STUDY OBJECTIVES: This study sought to estimate the probabilities of developing hypertension at different time periods in patients initiated on first line ART together with the associated factors. METHODOLOGY: A retrospective cohort study design was applied in conducting the study at the Kenyatta national hospital comprehensive care Centre involving HIV infected patients initiated in to first line ART between 2013- 2018. A sample of 904 patients was obtained using stratified simple random sampling method and followed up for hypertension development. Demographic, clinical and laboratory data of these patients was extracted from the electronic medical records, cleaned and coded in Ms excel. Analysis was done using STATA software version 20. Kaplan Meier was applied in estimating survival functions and Log rank tests in comparison of survival functions between patients based on different ART regimes. Cox proportional model was used to evaluate the associated factors with hypertension among the participants. RESULTS: 904 patients were included in the study, Kaplan meier estimated the median follow up time of the patients to develop hypertension to be 39 months and the log rank failure functions of patients differed significantly by age, diabetes status and smoking status while the hazard ratios of developing hypertension varied significantly with increasing age, BMI and smoking status. CONCLUSION: Efavirenz based ART regimen was detected to have more effects on blood pressure than the Nevirapine based one. More comparative studies need to be conducted to determine the effect of each individual ART drug to blood pressure in order to come up with the right combination with less harm to the patients.