January 11, 2006

Type 2 diabetics should have cardiac stress test

NEW YORK (Reuters Health) - Contrary to current guidelines,
"aggressive" efforts to detect coronary artery disease are
worthwhile in asymptomatic patients with type 2 diabetes, even
those with only one or no cardiovascular risk factors, a study
conducted in Italy suggests.

Current coronary artery disease screening guidelines from
the American Diabetes Association (ADA) recommend testing
asymptomatic patients with diabetes and two or more additional
risk factors. The guidelines state that asymptomatic diabetic
patients with none or only one other coronary artery disease
risk factor do not require cardiac testing, Dr. Roldano
Scognamiglio and colleagues from the University of Padua
Medical School note the American College of Cardiology.

In an attempt to "verify the effectiveness" of these
guidelines, the researchers studied 1,899 asymptomatic type 2
diabetic patients 60 years old or younger. They divided
patients into two groups: group A included 1,121 patients with
two or more coronary artery disease risk factors, and group B
included 778 patients with no or only one coronary artery
disease risk factor.

All of the subjects underwent cardiac stress tests and
those with coronary defects in blood flow underwent
angiography, which involves threading a catheter through a vein
into the heart and then injecting dye into the coronary blood
vessels. A series of X-rays are then taken to identify any

According to the team, the prevalence of abnormal stress
test findings was similar in group A and group B (59.4 percent
vs. 60 percent), as was the prevalence of significant coronary
artery disease (64.6 percent vs. 65.5 percent).

This suggests that a "substantial number of asymptomatic
diabetic patients with few risk factors might have occult
coronary artery disease," Scognamiglio and colleagues point
out. "These patients might have been missed on the basis of
current ADA guidelines."

Moreover, "patients with coronary artery disease unmasked
by an 'aggressive' approach had a more favorable angiographic
anatomy of coronary vessels," the team reports.

Patients in group B, they explain, were more apt to have
one-vessel disease and less likely to have three-vessel
disease, diffuse disease or occlusion. Based on the coronary
anatomy picture, revascularization was not an option in 45
percent of patients with two or more risk factors.

The researchers note that in this study the screening
criterion of two or more risk factors "did not help to identify
asymptomatic patients with a higher percentage of coronary
artery disease and is only related to a more severe coronary
artery disease with unfavorable coronary anatomy."

SOURCE: Journal of the American College of Cardiology,
January 3, 2006.