Low-dose aspirin for the prevention of atherothrombosis across the cardiovascular risk continuum

Abstract

Professor Junbo Ge welcomed speakers and attendees both present (25, 600) and virtual (120,000) to the International Aspirin Foundation (IAF) Symposium at the Oriental Congress of Cardiology (OCC). He introduced aspirin as the cornerstone of antiplatelet therapy with evidence for its efficacy and safety in cardiovascular disease (CVD) prevention accumulating since the 1970s. Aspirin works by irreversibly inactivating the cyclooxygenase (COX) activity of the ubiquitous bifunctional enzyme, prostaglandin (PG)G/H-synthase, which catalyzes the conversion of arachidonic acid to PGG 2 (through its COX activity) and PGH 2 (through its peroxidase activity) 1 . PGH 2 is a common intermediate in the biosynthesis of different prostanoids (e.g., PGE 2 , thromboxane [TX] A 2 and prostacyclin [PGI 2 ]), through the action of tissue-specific isomerases and synthases. three clinical case studies to illustrate his perspectives on aspirin’s role in the prevention of cardiovascular events using data from both primary and secondary prevention trials. For secondary prevention of CVD, in those with known atherosclerotic disease prior myocardial infarction the that risk of in serious thrombotic atrial clear benefits for low-dose aspirin. Two of Professor Gaziano’s case studies illustrated the types of people benefiting from aspirin for the secondary prevention of CVD. There are over 13.7 million new strokes worldwide each year, with individuals having a lifetime risk of 20%. TIA and minor stroke comprise 70% of all acute cerebrovascular events and often herald an impending major stroke, with seven-day risk of major stroke as high as 10% 1,2 . However, urgent medical assessment and treatment are very effective in preventing early recurrent major stroke. The EXPRESS study showed urgent investigation/treatment after TIA and minor stroke reduced the 90-day risk of major recurrent stroke by about 80% - one of the most effective interventions in medicine 3,4 . This benefit was achieved by changing care from non-urgent general practice prescribing to urgent assessment and treatment using existing medications. Other studies show similar feasibility and results 5 . However, the EXPRESS Study intervention was multifactorial, including aspirin, other antiplatelet drugs in high-risk patients, BP-lowering drugs and statins, and it was uncertain which component had reduced stroke risk. Aspirin was given to all patients, but the effect of aspirin on recurrent stroke risk had long been considered modest, based on trials in acute major stroke and in long-term prevention after TIA/minor stroke. By detailed re-analysis of individual patient data from these trials, it was shown the acute benefits of aspirin in TIA/minor stroke had been considerably underestimated, showing that aspirin alone reduced 90-day risk of disabling recurrent stroke by 80% and of all stroke by 60% 6 . Despite patients given benefits of aspirin. this, Professor Rothwell has with guideline writers recommend low-dose aspirin immediately after TIA and minor stroke, assessment/ investigation 7-9 . First-line (e.g. paramedics, recommendations for Aspirin has been shown to reduce the risk of cardiovascular disease (CVD) and increase the risk of bleeding including gastrointestinal (GI) bleeding in clinical trials and cohort studies 1 . As a result, the United States Preventative Task Force gave a grade B recommendation for taking low-dose aspirin for the primary prevention of CVD in adults aged 50 to 59 years at 10% risk for CVD over a ten years and low risk for bleeding 1-2 . Aspirin causes mucosal injury through prostaglandin-dependent topical and systemic mechanisms 3,4 . quantify bleeding risk with low-dose aspirin . In ASPREE, participants were to either 100mg There a aspirin and primary outcomes were death from any cause, dementia or persistent physical disability. for this composite the purposes of understanding bleeding risk the results showed that there were 162 major bleeding events in the aspirin arm compared with 102 the placebo arm GI GI it quantifies risk in older patients 6 .