Influence of Concomitant Treatments under Anticoagulants and Statins in Detecting Signals of Adverse Drug Reactions

The aim of the present study was to evaluate the risk of adverse drug reactions (ADRs) of concomitant treatments in patients treated with anticoagulants and statins. The authors performed an observational cross-sectional study in two cohorts of surveyed patients treated with vitamin K antagonists (VKAs) or non-vitamin K antagonist oral anticoagulants (NOACs). Different groups were analyzed based on the drug that each patient was taking, that is, VKAs or NOACs, as well as on the use of HMG CoA reductase inhibitors (statins) versus nonuse of these drugs; they also took into account the potential exposure to other common medications. Descriptive, clinical, and ADR data were reported and analyzed through an adaptation of Bayesian methodology (false discovery rate < 0.05) to detect new signals. Eleven different ADRs in patients on VKAs and statins and 12 in patients on VKAs without statins were found. In evaluating the concomitant therapies, the authors found that analgesics and nonsteroidal anti-inflammatory drugs were the most common therapeutic options, followed by proton pump inhibitors (PPIs). Seven ADRs were observed in patients concomitantly treated with NOACs and statins, whereas NOACs without concomitant statins were associated with a significantly lower risk of bleeding. The risk of observing an ADR among the patients who are concomitantly treated with VKAs and statins is lower than with analgesics or PPI, while the concomitant use of NOACs and statins is associated with both an increment in the number of observed ADRs and increased risk of bleeding.