Risk factor and sex differences in single versus multiple vessel coronary artery disease.

We analyzed 305 patients with either single or multiple vessel disease, as demonstrated by coronary arteriography, to determine risk factor and sex differences. Women accounted for more than one fourth of the patients with single vessel disease (group A), but for only one seventh of the individuals with multiple vessel disease (group B). Group A patients were younger and had fewer risk factors, and fewer abnormalities on chest roentgenogram, ECG, and stress test than those in group B. The better reported prognosis for patients with single (versus multiple) vessel coronary artery disease may be due to (1) slightly younger age, (2) greater representation by women, (3) fewer functional abnormalities as assessed by noninvasive tests, and (4) a lower incidence of cardiac risk factors. The presence of hypertension and diabetes seemed most likely to defeat the biologic advantage enjoyed by women over men in resistance to the development of atherosclerotic heart disease.