The impact of treatment choices on potential drug–drug interactions in hypertensive patients

Abstract

Aims: The aim of this study was to analyse potential drug–drug interactions (pDDIs) and their potential adverse drug reactions (ADRs) among hypertensive patients. Moreover, we investigated the possibility of reducing pDDIs with different treatment choices. Methods: This was a cross-sectional study including all outpatients with hypertension and two or more medications, treated in a university hospital in Serbia. Lexicomp Interact (Lexi-Comp, Inc., Hudson, OH) was used for identification of pDDIs and potential ADRs. Treatment choices were explored according to patient characteristics, treatment guidelines and the interacting potential of drugs. Data were analysed using descriptive analysis and multiple logistic regression. Results: A total of 350 patients were included in this study, with average age (77 [36–98] years and 6.1 [2.5]) medications. The majority of patients (86.0%) had at least one clinically significant pDDI, and the average was 3.78 (3.90) (range 1–25). Suggestions for treatment change aimed mainly at eliminating drug duplications, reducing the use of thiazide diuretics, sulfonylureas, alpha-lipoic acid and pentoxifylline and increasing the use of calcium-channel blockers, when appropriate. pDDIs would have decreased to 2.10 (2.52), P <.001, yet male gender, ≥6 medications, cardiovascular diseases, diabetes, benign prostatic hyperplasia, would be predictive of two or more pDDIs. The main potential adverse outcomes of pDDIs were hypotension, renal failure, hypoglycaemia, bradycardia and lactic acidosis. Conclusion: Careful choice of drugs can reduce but not eliminate pDDIs and their potential ADRs in hypertensive patients. Close monitoring for hypotension, renal failure, hypoglycaemia, bradycardia and lactic acidosis is necessary.