Coronary atherosclerosis in Type II diabetes: angiographic findings and clinical outcome

Aims/hypothesis. Prevalence and incidence of coronary heart disease (CHD) a re increased in patients with Type II (non-insulin-dependent) diabetes mell itus; whether this is entirely due to more extensive coronary atheroscleros is is, however, controversial. Methods. We analysed the clinical, angiographic and follow-up data of 2253 consecutive patients undergoing coronary angiography over the decade 1983-1 992. Results. Abnormal coronary arteries (greater than or equal to 50 % stenosis ) were found more frequently in diabetic than in non-diabetic subjects (85 vs 67 %, p < 0.0001), the excess being explained by a higher prevalence of three-vessel disease (36 vs 17 %, p < 0.0001). The sum of all angiographica lly detectable lumen stenoses (atherosclerosis score, ATS) was higher in di abetic than in non-diabetic subjects (352 +/- 232 vs 211 +/- 201 units, p < 0.0001). After adjusting for measured cardiovascular risk factors, diabete s was still associated with an excess ATS (114 units in men and 187 units i n women, p < 0.0001 for both, p < 0.03 for the interaction ATS x sex). With in the diabetic group, the only variable that was independently (of sex and age) associated with ATS was serum cholesterol, whereas plasma glucose con centration, disease duration and type of treatment were not correlated with the severity of coronary atherosclerosis. In contrast, clinical grade prot einuria was not associated with a more diffuse coronary atherosclerosis eit her in diabetic (366 +/- 243 vs 354 +/- 233 units) or non-diabetic subjects (231 +/- 201 vs 207 +/- 197 units). Over a mean follow-up period of 88 mon ths, 19 % of diabetic patients compared with 10 % of non-diabetic patients died of a cardiac cause (age and sex-adjusted odds ratio OR = 1.34 [1.14-1. 57]). In a Cox model adjusting for age, sex and all major risk factors, dia betes was still associated with a significant excess risk of dying of a car diac cause (OR = 1.37 [1.14-1.60]); this excess was similar to, and indepen dent of, that carried by the presence of prior myocardial infarction in the whole population (OR = 1.42 [1.25-1.62]). Proteinuria was associated with a higher risk of cardiac death, particularly in diabetic patients, independ ently of coronary atherosclerosis (adjusted OR = 1.46 [1.03-1.99]). Conclusion/interpretation. In patients undergoing angiography, diabetes, es pecially in women, is associated with more severe and diffuse coronary athe rosclerosis which is not explained by either the traditional risk factors o r the presence of proteinuria. On follow-up, these patients experience an e xcess of cardiac deaths, to which coronary atherosclerosis and proteinuria make independent, quantitative contributions.