PS-022 Polypharmacy and drug-drug interactions in adults with human immunodeficiency virus infection

Background Studies demonstrate that human immunodeficiency virus (HIV) patients may be at greater risk of age-related comorbidities, polypharmacy and medicines-related problems, such as drug-drug interactions (DDIs). Purpose To describe the characteristics of polypharmacy and DDIs in HIV patients. Material and methods We performed an observational-retrospective study of the pharmacotherapeutic profile (all drugs) and clinical record (demographic and clinical data) of adult HIV patients on stable antiretroviral treatment (ART, at least 6 months) in a general teaching hospital. We defined polypharmacy as the use ≥5 drugs. To define the impact of DDIs we used the Lexi-Interact drug-interaction database; interactions categorised as D (consider treatment modification) or X (avoid combination) were analysed and further stratified into one of the following groups: Type 1 = ART + non-ART; Type 2 = two non-ARTs; Type 3 = two ARTs. One-way ANOVA was performed to compare interactions by group. Results We evaluated 100 patients (female, 28; median age, 48 years; HCV co-infected, 43; HBV co-infected, 2; HCVH adherence Conclusion There is a medium-high level of polypharmacy and DDIs in our patients. Type 1 DDIs are significantly higher than the others, therefore greater attention to non-ART prescriptions is needed to ensure the safest drugs use in HIV patients. References and/or acknowledgements No conflict of interest.