Purpose: To assess the nature, severity, predictability and preventability of adverse drug reactions (ADRs) and to identify risk factors for antiretroviral ADRs.
Methods: Enrolled ambulatory patients were intensively monitored for ADRs. Spontaneously reported ADRs by clinicians were also included. Predictability was assessed based on history of previous exposure to the drug or literature incidence of ADRs. Preventability was assessed using Schumock and Thornton criteria and severity was assessed using modified Hartwig and Siegel scale. Bivariate analysis and subsequently multivariate logistic regression were used to identify the risk factors for ADRs. Data from spontaneous reporting was assessed using Bayesian neural network method for possible ADR signals.
Results: Monitoring by active surveillance indentified 159 (52.82%) ADRs from 400 patients. One hundred and forty-two (47.17%) reactions were spontaneously reported. Anaemia and vomiting were the most commonly observed ADRs. The ADRs were severe in 10.9% of cases. A total of 88% ADRs were definitely/probably preventable. Use of Zidovudine+Lamivudine with Nevirapine or Efavirenz, CD4 <200 cells/microl, female gender, tuberculosis and illiteracy were observed as risk factors for ADRs by bivariate analysis. Concurrent tuberculosis was the only influential risk factor for development of ADRs identified by multivariate logistic regression.
Conclusion: Prevalence of ADRs in intensively monitored patients was found to be 39.7%. Tuberculosis in HIV patients is an influential risk factor for occurrence of ADRs. With the increasing access to antiretrovirals in India, ADRs to antiretrovirals require monitoring and reporting.