Coronary artery disease is common in nonuremic, asymptomatic type 1 diabetic islet transplant candidates.
OBJECTIVE
Coronary artery disease (CAD) is the most common cause of death in patients with type 1 diabetes. Asymptomatic CAD is common in uremic diabetic patients, but its prevalence in nonuremic type 1 diabetic patients is unknown. The prevalence of CAD was determined by coronary angiography and the performance of noninvasive cardiac investigation evaluated in type 1 diabetic islet transplant (ITX) candidates with preserved renal function.


METHODS
A total of 60 consecutive type 1 diabetic ITX candidates (average age 46 years [mean 24-64], 23 men, and 47% ever smokers) underwent coronary angiography, electrocardiographic stress testing (EST), and myocardial perfusion imaging (MPI) in a prospective cohort study. CAD was indicated on angiography by the presence of stenoses >50%. Models to predict CAD were examined by logistic regression.


RESULTS
Most subjects (53 of 60) had no history or symptoms of CAD; 23 (43%) of these asymptomatic subjects had stenoses >50%. CAD was associated with age, duration of diabetes, hypertension, and smoking. Although specific, EST and MPI were not sensitive as predictors of CAD on angiography (specificity 0.97 and 0.93, sensitivity 0.17 and 0.04, respectively) but helped identify two of three subjects requiring revascularization. EST and MPI did not enhance logistic regression models. A clinical algorithm to identify low-risk subjects who may not require angiography was highly sensitive but was applicable only to a minority (n = 8, sensitivity 1.0, specificity 0.27, negative predictive value 1.0).


CONCLUSIONS
Nonuremic type 1 diabetic patients with hypoglycemic unawareness and/or metabolic lability referred for ITX are at high risk for asymptomatic CAD despite negative noninvasive investigations. Aggressive management of cardiovascular risk factors and further investigation into optimal cardiac risk stratification in type 1 diabetes are warranted.
Senior
Peter A
PA
Clinical Islet Transplant Program, University of Alberta, 8215 112th St., Edmonton, Alberta, Canada T6G 2C8. petersenior@ualberta.ca
Welsh
Robert C
RC
McDonald
Charlotte G
CG
Paty
Breay W
BW
Shapiro
A M James
AM
Ryan
Edmond A
EA
D000328:Adult; D000368:Aged; D001364:Awareness; D001794:Blood Pressure; D002096:C-Peptide / Q000097:blood; D017023:Coronary Angiography; D003327:Coronary Disease / Q000453:epidemiology*; D023921:Coronary Stenosis / Q000453:epidemiology; D003922:Diabetes Mellitus, Type 1 / Q000601:surgery*; D003925:Diabetic Angiopathies / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007003:Hypoglycemia / Q000503:physiopathology; D016381:Islets of Langerhans Transplantation / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology; D011237:Predictive Value of Tests; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012907:Smoking
D002096:C-Peptide