Low-dose aspirin therapy is a reasonable approach to prevent a first myocardial infarction or stroke among patients with diabetes at high risk for cardiovascular disease, according to a joint statement released by the American Diabetes Association, American College of Cardiology and American Heart Association.

Patients with diabetes eligible for low-dose aspirin therapy, based on this guideline, include most men aged 50 years or older and most women aged 60 years or older who have additional CV risk factors and no excess bleeding risk. 

“Because the relative risk reduction appears to be modest, the panel felt that we are on strongest ground recommending aspirin for those at increased CVD risk, defined by the age categories and risk factors mentioned or by a calculation of CVD risk,” Michael Pignone, MD,  chief of the general medicine division and professor of medicine at the University of North Carolina, Chapel Hill, said in a press release. “We felt that the benefits were likely to exceed the downsides, such as gastrointestinal bleeding, for the groups mentioned. There will be some younger people with sufficient risk to warrant aspirin, but many who are not at sufficient risk.”

The statement was published online in the Journal of the American College of Cardiology, Diabetes Care and Circulation: Journal of the American Heart Association.

Previous research

The authors said scientific evidence to support aspirin therapy depends on the underlying CVD risk. Overall, data suggest that aspirin moderately reduces this risk; however, more research is needed to better define the specific effects of aspirin on diabetes.

For the recommended target group, those with the highest CV risk should experience the greatest benefits, according the statement. However, the use of aspirin therapy depends on the use of other treatments, such as cholesterol-lowering medications, blood pressure control and smoking cessation.

In 2007, the ADA and AHA issued a joint recommendation for 75 mg to 162 mg aspirin per day for men and women aged 40 years or older with a major risk factor for CVD, such as family history, hypertension, smoking, hypercholesterolemia or proteinuria.

“The new recommendations only address primary prevention,” Craig Williams, PharmD, associate professor of pharmacy and medicine at Oregon Health Sciences University, Portland, said in a press release. “All three organizations continue to strongly recommend low-dose aspirin for all patients who have previously had a heart attack or stroke, so-called secondary prevention.”

Low-dose aspirin is not recommended for CV prevention for men younger than 50 years and women younger than 60 years with diabetes and no major additional CV risk factors because the potential adverse events from gastrointestinal bleeding offset potential benefits of treatment, according to the statement. It is estimated that as many as one in five excess events occur per 1,000 patients per year. Intracranial bleeding is another previously noted major adverse effect of aspirin therapy.

Two ongoing studies are expected to provide additional information on the role of low-dose aspirin for the prevention of CV events, particularly in those with diabetes. – by Jennifer Southall and Katie Kalvaitis

The most recent scientific statement from the ACC/ADA/AHA indicates that men older than 50 years and women older than 60 years with diabetes should use low-dose aspirin for CV risk reduction. The authors admit that the data are not very strong for primary prevention, but feel that since the CV risk associated with diabetes is much higher than the general population it is warranted. This group of experts looked at all of the available data, including recent meta-analyses that indicate, in general, no significant benefit in these age groups and yet no significant increase in risk for bleeding. So, this recommendation is not based on A-level evidence, but rather the understanding, as they clearly state, that those at higher risk for CV events may benefit without a substantial increase in untoward effects. Those younger than 50 years clearly do not achieve benefit from low-dose aspiring and, hence, the statement does not recommend its use in this group.

The recommendation for low-dose aspirin seems generally reasonable and, as always, using agents that do not have A- or even strong B-level evidence leaves one a little unsure. Hence, we need to individualize therapy based on the CV risk of a given patient rather than taking a global recommendation.

– George Bakris, MD
Endocrine Today Editorial Board member