Moving Toward a Greater Focus on
Cardiovascular Disease in Diabetes

William Herman, MD, MPH

Cardiovascular disease is the leading cause of mortality and morbidity in people with diabetes.¹ In 1990, about half of all diabetes-related deaths had major cardiovascular disease listed as the underlying cause. In 1990, there were 2.8 million diabetes-related hospital discharges accounting for 24.5 million days of hospital stay. The most frequently listed primary diagnosis among diabetes-related discharges was diseases of the circulatory system (33% of discharges).

The American Diabetes Association’s (ADA’s) position statement "Aspirin Therapy in Diabetes," which is reprinted on the following two pages, represents a major step forward in recognizing and addressing the substantial burden of cardiovascular disease in diabetes.

In a technical review that was published with this new position statement when it originally appeared in the journal Diabetes Care, Colwell reviews the rationale for the use of aspirin in diabetes and the evidence on efficacy, safety, and dosage.² The evidence is unassailable for the efficacy of aspirin as a secondary prevention of vascular events (nonfatal myocardial infarctions [MIs], nonfatal stroke, or vascular death) in patients with acute MI, unstable angina, past history of MI, transient ischemic attack or stroke, and in those having coronary vascular procedures, stable angina, peripheral vascular disease, atrial fibrillation, or valvular heart disease.³ Both the proportional reduction in risk and, perhaps more importantly, the absolute reduction in risk were large.³

The evidence is less clear for the efficacy of aspirin as a primary prevention of vascular events, especially among younger people. The largest primary prevention trial to include a diabetic subanalysis, the U.S. Physicians’ Health Study, found that aspirin reduced the risk of MI, but only among those who were 50 years of age and older.⁴ In the diabetic subanalysis, aspirin reduced the risk of MI from 10.1% to 4.0%, but the effect was not assessed by age, and the trial only enrolled subjects 40 years of age and older.

The ADA recommends considering aspirin therapy as a primary prevention strategy in all people with diabetes and any other cardiovascular risk factor, including family history of coronary heart disease, obesity, hypertension, dyslipidemia, cigarette smoking, or albuminuria, regardless of age. This seems reasonable, but it goes beyond the available evidence and must be considered expert opinion.

This position statement must also be put into the larger context of cardiovascular disease prevention and control. Primary prevention must also focus on aggressive efforts to detect and treat hypertension, dyslipidemia, and tobacco abuse. Secondary interventions must address these risk factors and the appropriate use of ß-blockers following MI and ACE-inhibitors for patients with left-ventricular dysfunction and congestive heart failure.

A greater focus on cardiovascular disease in diabetes and implementation of the recommendations outlined in the position statement, as well as other proven primary and secondary interventions for cardiovascular disease, will have an important impact on the health of people with diabetes.

References

¹Centers for Disease Control and Prevention: Diabetes Surveillance, 1993. Atlanta, GA, U.S. Department of Health and Human Services, Public Health Service, 1993.

²Colwell JA: Technical review: Aspirin therapy in diabetes. Diabetes Care 20:1767-71, 1997.

³Antiplatelet Trialists’ Collaboration: Collaborative overview of randomised trials of antiplatelet therapy-I: prevention of death, myocardial infarction, and stroke by prolonged antiplatelet therapy in various categories of patients. Br Med J 308:81-106, 1994.

⁴Steering Committee of the Physicians’ Health Study Research Group: Final report on the aspirin component of the ongoing Physicians’ Health Study. N Engl J Med 321:129-35, 1989.

William Herman, MD, MPH, is an associate professor of internal medicine in the Division of Endocrinology and Metabolism at the University of Michigan in Ann Arbor. He is an associate editor of Clinical Diabetes.