 Aspirin is a blood thinner, so it affects platelet function, so it affects clotting and increases the risk of bleeding. Dr. Ashish Saraju with Cleveland Clinic is one of the authors of a new study looking at daily aspirin use across the U.S. since the recommendation changed. They found that in 2021, about one in three patients 60 and older who did not have a history of heart disease were still taking aspirin every day for prevention.