Aspirin has a well-established role in preventing adverse events including heart attack and strokes in patients with known cardiovascular disease. Surprisingly, the benefit of aspirin use in patients without any history of cardiovascular disease is not as clear as one would think, particularly in people with diabetes mellitus, women, and the elderly. Due to ongoing clinical research, recommendations for aspirin use can be confusing, as subtle changes in guidelines often go unnoticed. It is the intention of this review to help clarify the risks, benefits, and optimal use of aspirin in preventing cardiovascular events. I will do this in two separate articles to help simply the current thoughts that have led to current aspirin use recommendations.
Aspirin, also known as acetylsalicylic acid, is an analgesic (painkiller), antipyretic (reduces fevers), and an anti-inflammatory agent, but the most prominent use today is as an agent to treat or prevent cardiovascular events. This is based on the ability of aspirin to decrease or prevent the amount of clotting that can occur inside a blood vessel. It is this anti-clotting properly in the blood is what is responsible for the reduction of heart attacks and strokes. Approximately 50 million people in the United States take aspirin on a daily basis to treat or prevent cardiovascular disease. At least half of these people take more than the recommended amount per day, which reflects the misconception that for aspirin dosage "more is better", which is not true.
From a historical purpose, synthetic aspirin was initially developed to treat fevers and inflammation in 1897. In 1974, first landmark trial of aspirin for the secondary prevention of heart attacks was published. In 1982, a Noble Prize was awarded for the discovery of how aspirin actually works on a biochemical basis. In 1985, the FDA approved aspirin for the treatment and secondary prevention of acute heart attack. Finally, in 1998, the Second International Study of Infarct Survival (ISIS-2) found that giving aspirin to patients with a heart attack within 24 hours of the event led to significant reduction in the number of vascular deaths.
Currently, aspirin use is indicated for any patient with a suspected heart attack. Since there is 600,000 events related to atherosclerotic disease in the heart arteries and 325,000 recurrent events per year in the United States, and the fact that it is also approved to prevent and treat stroke, the need for aspirin will continue to remain great. The biggest issue that most patients and physicians face relates to the amount of aspirin that should be taken and about the appropriate use in specific patient populations. The early prevention trials used a wide range of doses, included few women, few people with diabetes mellitus, and few elderly people. This has made it confusing to summarize simplistic aspirin guidelines for preventing cardiovascular disease and stroke including looking at the risk versus the benefit ratio, to such a diverse patient population.
In the second part of my review, I will give a more in-depth summary of aspirin guidelines for preventing cardiovascular disease and stroke that have been published by the American Heart Association/American College of cardiology, The United States Preventative Services Task Force, and the American Diabetic Association. I will also attempt to outline in easy algorithm for aspirin use in the primary prevention of first cardiovascular events and in the secondary prevention of recurrent cardiovascular events. For more information on this topic or any other topic related to cardiovascular disease, one can visit http://www.lipidcenter.com