Title : The impact of enteric coating of aspirin on aspirin responsiveness in patients with suspected or newly diagnosed ischemic stroke: Prospective cohort study: Results from the (ECASIS) study
Abstract:
Background and purpose: Uncertainty remains regarding the impact of enteric-coated aspirin (EC-ASA) on secondary prevention of ischemic stroke compared to plain aspirin (P-ASA). Hence, this study was designed to investigate the efect of EC formulation on ASA response via evaluating thromboxane B2 (TXB2) levels in patients with suspected or newly diagnosed stroke.
Methods: A prospective cohort study on suspected or newly diagnosed ischemic stroke patients who are aspirin-naive was conducted. Patients were received either EC aspirin or plain aspirin for at least 3 days. The primary outcome was the proportion of aspirin non-responsiveness between two groups (level of residual serum TXB2 associated with elevated thrombotic risk (3.1 ng/ml) within 72 h after three daily aspirin doses, while secondary outcomes were the incidence of early gastrointestinal tract (GIT) bleeding with the various aspirin preparations. (Trial registration: Clinicaltrials.gov NCT04330872 registered on 02 April 2020).
Results: Of 42 patients, ischemic strokes were confrmed in both P-ASA (81%) and EC-ASA (67%) arms. ASA non-responsiveness showed no signifcant diference between the two formulations (P-ASA vs. EC-ASA; 28.6% vs 23.8%; P=0.726). Univariate and multivariate logistic regression analysis showed that patients treated with EC-ASA were more likely to have a lower rate of non-responders compared to P-ASA (unadjusted OR 0.78; 95% CI 0.20, 3.11); with the risk highest in type 2 diabetic patients with HBA1c>6.5% (adjusted OR 6; 95% CI 1.02, 35.27; P=0.047). No incidence of GIT bleeding observed throughout the study.
Conclusion: A signifcant proportion of ASA non-responsiveness was recorded regardless of ASA formulation administered. The increased risk of ASA non-responsiveness in diabetic patients needs further exploration by larger prospective studies.
Keywords: Plain aspirin; Enteric-coated aspirin; Aspirin response; Thromboxane B2; Stroke
