confirmed aspirin resistance confers increased rates of poorer outcomes in cardiovascular and neurovascular diseases. Although the majority of research conducted has surrounded cardiovascular and neurovascular, there is emerging research into the risk of aspirin resistance after orthopaedic surgery where aspirin is used for venous thromboembolism prophylaxis. Aspirin resistance in orthopaedic surgery, specifically after total hip and knee arthroplasties, is of interest as risk factors for aspirin resistance are also risk factors for venous thromboembolisms and osteoarthritis; the sequalae of requiring a total hip or knee arthroplasty. Some of these risk factors include obesity, advancing age, diabetes mellitus, dyslipidaemia and inflammatory diseases. Dosages Adult aspirin tablets are produced in standardised sizes, which vary slightly from country to country, for example 300mg in Britain and 325mg (or 5 grains) in the United States. Smaller doses are based on these standards, e.g., 75mg and 81mg tablets. The tablets are commonly called "baby aspirin" or "baby-strength", because they were originallybut no longerintended to be administered to infants and children. No medical significance occurs due to the slight difference in dosage between the 75mg and the 81mg tablets. The dose required for benefit appears to depend on a person's weight. For those weighing less than , low dose is effective for preventing cardiovascular disease; for patients above this weight, higher doses are required. In general, for adults, doses are taken four times a day for fever or arthritis, with doses near the maximal daily dose used historically for the treatment of rheumatic fever. For the prevention of myocardial infarction (MI) in someone with documented or suspected coronary artery disease, much lower doses are taken once daily. March 2009 recommendations from the USPSTF on the use of aspirin for the primary prevention of coronary heart disease encourage men aged 45–79 and women aged 55–79 to use aspirin when the potential benefit of a reduction in MI for men or stroke for women outweighs the potential harm of an increase in gastrointestinal hemorrhage. The WHI study of postmenopausal women found that aspirin resulted in a 25% lower risk of death from cardiovascular disease and a 14% lower risk of death from any cause, though there was no significant difference between 81mg and 325mg aspirin doses. The 2021 ADAPTABLE study also showed no significant difference in cardiovascular events or major bleeding between 81mg and 325mg doses of aspirin in patients (both men and women) with established cardiovascular disease.