The Incidence of Adverse Drug Reaction Among Adult Patients on Antiretroviral Therapy in Ethiopia: Frailty Model

INTRODUCTION: Adverse drug reactions are a major global public health concern and an important cause of hospitalization, discontinuation of the drug, morbidity and mortality. Even though the prevalence in Ethiopia was declining at a moderate rate, still, far too many people are suffering and dying unnecessarily due to adverse drug reactions. OBJECTIVE: The aim of this study was to determine the incidence of adverse drug reaction and its predictors among adult patients on antiretroviral therapy. METHODS: A retrospective follow-up study was conducted at Nigist Elleni Mohamed Memorial Comprehensive Specialized Hospital, Southern Ethiopia. Data were extracted from patients’ medical records. The Weibull model with gamma frailty distribution was fitted. Statistical significance was employed at a 5% level of significance and adjusted hazard ratio with 95% confidence interval was used. RESULTS: Out of the total 376 participants followed for 1988 person years of observations, 96 developed adverse reaction with the incidence rate of 4.820/100 per (95%CI: 4.102–5.317). The univariate frailty was statistically significant (theta=0.306, 95%CI: 0.102–0.521). Baseline CD4 count (AHR: 0.997, 95%CI: 0996–0.998), fair adherence (AHR: 2.358, 95%CI: 1.133–4.904), poor adherence (AHR: 3.069, 95%CI: 1.730–5.445), HIV/TB coinfection (AHR: 2.069, 95%CI: 1.115–3.843), WHO stage II (3.128, 95%CI: 1.414–6.916), WHO stage III (AHR: 2.709, 95%CI: 1.048–7.025) and WHO stage IV (1.516, 10.352) were associated with the incidence adverse reaction. CONCLUSION: Most of the ADR cases occurred within two years after initiation of ART. Advanced clinical stage, TB coinfection, CD4 count, and poor adherence were predictors of ADRs. Continuous counseling for clients in advanced clinical stage and patients with TB coinfection need to get close follow-up to prevent the associated ADRs by the concerned parties.