Aspirin is fine for headaches but like much of epidemiological correlation that suggests cause and effect, link aspirin to fewer heart attacks has been nothing but a subsidy for companies. New results of the ASPREE trial presented today at ESC Congress 2019 show it doesn't help older people even if they are in the highest risk of cardiovascular disease.

In America, where we have created pre-diabetes to try and convince people they are already ill and need medication, an aspirin regimen is common, due to belief it helps prevent cardiovascular disease. That is not the case in Europe for people who do not have free from cardiovascular disease  because there is increased risk of major bleeding (doi:10.1093/eurheartj/ehw106).

Trials have found it does not help moderate risk patients (ARRIVE - doi: 10.1016/S0140-6736(18)31924-X), diabetic patients (ASCEND -doi: 10.1056/NEJMoa1804988),or people over 70 (ASPREE - doi: 10.1056/NEJMoa1805819).

In that last group, chances of moderation reduction in  cardiovascular disease risk(CVD) were outweighed by increased bleeding hazard.

The primary finding from the ASPREE randomized trial was that in people aged 70 years or over with no known CVD, there was no effect of 100 mg of daily aspirin on the composite primary endpoint of disability-free survival (defined as those not reaching a primary endpoint of dementia or persistent physical disability or death).The primary endpoint was chosen to reflect the reasons for prescribing a preventive drug in an otherwise healthy elderly population.

This analysis examined whether the results for the primary endpoint of disability-free survival might vary by the baseline level of CVD risk. Analyses were also conducted for the secondary endpoints of all-cause mortality, major hemorrhage, and prevention of CVD (defined as fatal coronary heart disease, nonfatal myocardial infarction, fatal or nonfatal stroke, or hospitalization for heart failure). 

The investigators calculated ten-year CVD risk probabilities at baseline for the 19,114 ASPREE participants using the Framingham score (up to 75 years) and the atherosclerotic cardiovascular disease (ASCVD) pooled cohort risk equations (up to 79 years) and divided them into thirds. As there are no CVD risk scores available beyond the age ranges specified in the equations, they also classified participants according to the presence of 0 to 1, 2 to 3, or more than 3 CVD risk factors. Overall rates of disability-free survival, mortality, major bleeding and CVD were examined for each risk group and outcomes were compared for those treated with aspirin or placebo.

For participants in the lowest third of CVD risk, by both Framingham and ASCVD scores, there was no disability-free survival or cardiovascular benefit from aspirin. This group also had the highest likelihood of bleeding.

In contrast, those in the highest third of CVD risk, by both Framingham and ASCVD scores, had significantly lower CVD event rates on aspirin with similar rates of bleeding. Hazard ratios for CVD reduction with aspirin version placebo were 0.72 (95% confidence interval [CI] 0.54-0.95) for the group classified as high risk by the Framingham score and 0.75 (95% CI 0.58-0.97) for those defined as high risk by the ASCVD equations.

However, this reduction in CVD did not translate to a significantly improved disability-free survival. Hazard ratios for disability-free survival with aspirin versus placebo were 0.86 (95% CI 0.62-1.20) for the group designated high risk by the Framingham score and 0.89 (95% CI 0.62-1.28) for those considered high risk by the ASCVD equations.