Diabetic control and left ventricular ejection fraction during cold stimulation tests in insulin-dependent diabetes.

Abnormal cold stimulation (CS) tests have been reported in diabetic patients compared with normal controls. This result could be influenced by factors such as age, autonomic neuropathy, duration of diabetes and diabetic control and a group of type I (insulin-dependent) diabetic patients were therefore investigated to assess the effect of these factors on the CS test. Fifteen out of 31 patients (48.4%) had an abnormal change in left ventricular ejection fraction (LVEF) during CS. There was no correlation between the change in LVEF and age, autonomic function tests, duration of diabetes or plasma glucose levels during the test. There was a significant negative correlation between the change in LVEF and HbA1 levels (r = 0.42; p = 0.02). We cannot say whether these results indicate a functional abnormality or a structural lesion of the coronary arteries or myocardium. They suggest, however, that diabetic control may influence cardio-vascular responses in diabetic patients.