Friday, March 26, 2010

ASPIRIN IN THE PRIMARY PREVENTION OF HEART ATTACKS - UPDATE

In the 90's it was seemed well established that aspitrin had an important role in the prevention of heart attacks. The results of numerous anti-platelet trialist collaborations seemed to established that. In fact, we were all wondering whether we should all take a bit of aspirin? That went on for 10 years. Then in 2009, the " Aspirin Treatment Trialist Collaboration " group reviewed 6 mega-aspirin trials, including the US physician health study, the Women's Health study, the British Doctors study, the Thrombosis Prevention study, the Primary Prevention Project and also the HOT study, and found that the small benefit in the use of aspirin was far aoutweight by the significant side effects with aspirin. The ATTC was a meta-analysis of the mega-trials. That was 2009. Before I forget, they also reviewed the data for secondary prevention and found that aspirin was very useful in the secondary prevention. The event reduction was much more ( then primary prevention ), so that the small number of side effects was acceptable.
At the just concluded ACC Annual Scientific Meeting at Atlanta, Georgia, Dr Jay Das and group re-reviewed the ATTC data, plus another three aspirin trials ( the JPAD, POPADAD, AAA ) and also concluded basically, that althought there was some small benefit with aspirin, there was a significant level of side effects. They concluded that there was no role for aspirin in the primary prevention of heart attacks.
What has changed between the 90's and now for this turn around?
Thinking hard over it, it looks like the cohort of subjects studied in the 90's and new millenium ( the cohort studied by the trials used by the ATTC group ), are also taking statins and beta-blockers, resulting in more protection against heart attacks. Therefore the effects of aspirin was muted, when compared to the cohort of the 70's and 80's which form the cohort of the earlier Anti-platelet Trialist Collaborations of the 80's. This again showing that with clinical trials, the meieu and target is ever-changing and results have to be viewed with in the context of the trials.
Be that as it may, in the year 2010, it does looks like aspirin helps little, in the primary prevention of heart attacks, and does do harm, in terms of bleeging and gastric toxicity. Therefore there is no role for aspirin in the primary prevention of heart attacks. However, there is a very definite role for aspirin in the secondary pevention of heart attacks.
I wonder if 10 years from now, I will have to revise this position again.

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