Are predictors of coronary heart disease and lower-extremity arterial disease in type I diabetes the same? A prospective study

In the Type 1 diabetes population, coronary heart disease (CHD) and lower-e xtremity arterial disease (LEAD) are the two common macrovascular complicat ions leading to early mortality and morbidity. However, it is not clear if these two complications share the same risk factors. The Pittsburgh Epidemi ology of Diabetes Complications (EDC) Study prospectively examined and comp ared the risk factors for LEAD and CHD (including CHD morbidity and mortali ty). EDC subjects (332 men and 325 women), all diagnosed at Children's Hosp ital of Pittsburgh between 1950 and 1980, were first examined at baseline ( 1986-1988), and then biennially, for diabetes complications and their risk factors. Data used in the current analysis were from the first 6 years of f ollow-up, 98% provided at least some follow-up data for these analyses. CHD was defined as the presence of angina (diagnosed by the EDC examining phys ician) or a history of confirmed myocardial infarction or CHD death. An ank le-to-arm ratio of less than 0.9 at rest was considered to be evidence of L EAD. Among 635 subjects without CHD at baseline, 57 developed CHD (1.69/100 person-years), and among 579 without LEAD at baseline, 70 developed LEAD ( 2.31/100 person-years). CHD incidence rate was slightly higher in males, wh ile LEAD incidence rate was slightly higher in females. Compared to non-inc ident cases, subjects who developed either complication were older, had a l onger diabetes duration, higher LDL and total cholesterol, and were more li kely to be hypertensive. In multivariate analyses, hypertension, low HDL ch olesterol level, high white cell count, depression, and nephropathy were th e independent risk factors for CHD (including morbidity and mortality). For LEAD, higher HbAl level, higher LDL cholesterol lever and smoking were the important contributing factors. In conclusion, the risk factor patterns di ffer between the two vascular complications. Glycemic control does not pred ict CHD overall but does predict LEAD, while hypertension and inflammatory markers are more closely related to CHD than to LEAD. (C) 2000 Elsevier Sci ence Ireland Ltd. All rights reserved.