Estimating Time in Therapeutic Range in Cardiology and Neurology Patients on Warfarin/Acenocoumarol: Assessing its Association with Clinical Outcomes and Influencing Factors for it’s Reliable Use in General Practice

Introduction

Anticoagulant therapy is a cornerstone in the management of various cardiovascular diseases and neurological disorders, including atrial fibrillation, deep vein thrombosis, pulmonary embolism, and stroke prevention. These medications have well-proven effectiveness for those indications but pose significant challenges including increased bleeding risk due to the narrow therapeutic window and the high variability in patient response.¹ According to several studies, anticoagulants, particularly in ambulatory care, were accountable for 12% of adverse reactions because of their risk of bleeding. Keeping patients within their therapeutic range, which is commonly expressed as time in therapeutic range (TTR), will help to enhance the efficacy of anticoagulant medication.TTR is a critical parameter indicating the proportion of time a patient’s International Normalized Ratio (INR) is within the target range, reflecting effective anticoagulation and minimizing the risk of adverse events and it is important to determine the current standard of anticoagulation care and establish new objectives. It has been found that TTR can strongly predict both bleeding and thromboembolic events.²A greater TTR can improve anticoagulation therapy whereas suboptimal TTR is associated with increased risks of thromboembolic events when INR is too low and hemorrhagic complications when INR is too high.Using these integrated statistics, TTR shows the days with INRs between 2.0 and 3.0 over the total number of days.²Therefore, regular monitoring and appropriate dose adjustments are essential to maintain therapeutic efficacy and safety.The most used method to calculate TTR is the Rosendaal linear interpolation method.^3-4The value is calculated from the number of days within target range divided by the total number of days in the observation period. The cardiology and neurology departments are at the forefront of managing patients requiring anticoagulant therapy due to the high prevalence of cardiovascular and cerebrovascular conditions in these specialties.⁵ A thorough evaluation of TTR and safety audits in these settings can provide valuable insights into current practices, identify areas for improvement, and enhance patient outcomes. The current study aims to evaluate the TTR and conduct a safety audit of anticoagulant therapy in patients attending the cardiology and neurology departments. By analyzing TTR, adverse drug reactions (ADRs), and adherence to clinical guidelines, this research seeks to optimize anticoagulant management, lessen the incidence of complications, and enhance the standard...