NEW ORLEANS — Despite having a higher incidence of metabolic syndrome, women had less obstructive coronary artery disease in a study of 468 patients who presented for elective cardiac catheterization.
Nondiabetic women were significantly more likely to have metabolic syndrome than were their nondiabetic male counterparts (52% vs. 28%), although nondiabetic men had a significantly greater percentage of coronary artery disease (CAD) (42% vs. 18%). Dr. Andrew Weissman and colleagues from Lenox Hill Hospital in New York City reported their findings in a poster at the Southern regional meeting of the American Federation for Medical Research.
The results call into question whether lower cutoffs should be used to identify metabolic syndrome in women or whether the presence of metabolic syndrome itself is truly a risk factor for coronary artery disease, Dr. Weissman said in an interview.
“The goal of identifying metabolic syndrome is to try and pick out those people with a higher risk for coronary artery disease and it doesn't seem to be doing that in nondiabetic females according to the results of our study,” he said.
The study included 277 men (mean age 60 years) and 191 women (mean age 63 years) with no known history of CAD. Metabolic syndrome was evaluated using the National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP III) criteria.
The NCEP criteria recommend that metabolic syndrome be identified if three or more of the following risk factors are present: waist circumference of 102 cm or more in men and 88 cm or more in women; elevated triglyceride level of 150 mg/dL or greater; reduced HDL cholesterol level of less than 40 mg/dL in men and less than 50 mg/dL in women; elevated blood pressure of 135/85 mm Hg or greater; and an elevated fasting glucose of 110 mg/dL or greater.
Diabetes mellitus was present in 79 men (28.5%) and 49 women (25.6%), a difference that was not statistically significant.
Metabolic syndrome was present in 233 of 468 patients and was found in a significantly higher percentage of women (62%) than men (41%).
CAD, defined as the presence of 70% or greater stenosis in one of the three major coronary vessels or 50% stenosis in the left main coronary artery, was present in 48 (25%) women and in 132 (48%) men.
There was no significant difference between patients with and without metabolic syndrome with regard to mean Framingham risk score or for age, tobacco use, or family history of CAD, said Dr. Weissman, a third-year cardiology fellow at Lenox Hill Hospital.
However, both men and women with diabetes were significantly more likely to have CAD than were their nondiabetic counterparts.
There was no significant difference in percentage of CAD between men and women with diabetes (62% vs. 45%). There was a trend toward women with diabetes being more likely to have metabolic syndrome than were men with diabetes (90% vs. 75%), but it was not statistically significant, the authors wrote.
Although diabetes is considered a coronary risk equivalent, the independent significance of metabolic syndrome in practice remains controversial.
“The clinical implication is that our study results do not support the use of metabolic syndrome as a useful risk stratifier for coronary artery disease,” Dr. Weissman said.