Estimating Aspirin Overuse for Primary Prevention of Atherosclerotic Cardiovascular Disease (from a Nationwide Healthcare System).

The American College of Cardiology and American Heart Association recently published guidelines narrowing the indications for low-dose aspirin use. The suitability of the electronic health record (EHR) to identify patients for low-dose aspirin deprescribing is unknown. To apply the 3 low-dose aspirin guidelines to EHR data, the guidelines were deconstructed into components from their narrative text and assigned computer-interpretable definitions based on electronic data interchange standards. These definitions were used to search EHR data to identify patients for aspirin deprescribing. To verify EHR records for low-dose aspirin, we then compared the records with a survey of patients' self-reported use of low-dose aspirin. Of the 3 aspirin guidelines, only 1 had a definition suitable for EHR implementation. The other 2 contained difficult-to-implement phrases (e.g., "higher ASCVD risk", "increased bleeding risk"). An EHR search with the single implementable guideline identified 86,555 people for possible aspirin deprescribing (2% of 5,598,604). Only 676 of 1,135 (60%) patients who self-reported taking low-dose aspirin had an active EHR record for low-dose aspirin at that time. Limitations exist when using EHR data to identify patients for possible low-dose aspirin deprescribing such as incomplete EHR capture of and the interpretation of non-specific terminology when translating guidelines into an electronic equivalent. In conclusion, data show many people unnecessarily take low-dose aspirin.