Influence of diabetes mellitus on early and late outcome after percutaneous transluminal coronary angioplasty.

BACKGROUND

Although patients with diabetes mellitus constitute an important segment of the population undergoing coronary angioplasty, the outcome of these patients has not been well characterized.

METHODS AND RESULTS

Data for 1133 diabetic and 9300 nondiabetic patients undergoing elective angioplasty from 1980 to 1990 were analyzed. Diabetics were older and had more cardiovascular comorbidity. Insulin-requiring (IR) diabetics had diabetes for a longer duration and worse renal and ventricular functions compared with non-IR subjects. Angiographic and clinical successes after angioplasty were high and similar in diabetics and nondiabetics. In-hospital major complications were infrequent (3%), with a trend toward higher death or myocardial infarction in IR diabetics. Five-year survival (89% versus 93%) and freedom from infarction (81% versus 89%) were lower, and bypass surgery and additional angioplasty were required more often in diabetics. In diabetics, only 36% survived free of infarction or additional revascularization compared with 53% of nondiabetics, with a marked attrition in the first year after angioplasty, when restenosis is most common. Multivariate correlates of decreased 5-year survival were older age, reduced ejection fraction, history of heart failure, multivessel disease, and diabetes. IR diabetics had worse long-term survival and infarction-free survival than non-IR diabetics.

CONCLUSIONS

Coronary angioplasty in diabetics is associated with high success and low complication rates. Although long-term survival is acceptable, diabetics have a higher rate of infarction and a greater need for additional revascularization procedures, probably because of early restenosis and late progression of coronary disease. The most appropriate treatment for these patients remains to be determined.