AUTONOMIC FUNCTION IN A COHORT OF CHILDREN WITH DIABETES

129 diabetic children in Avon County participated in a longitudinal st udy of the evolution of microvascular disease together with 129 age-an d sex-matched controls, Diabetic children had mean (+/-SD) age 12.7 (/-3.4) years (range: 3.7-16.8), mean (+/-SD) diabetes duration 3.9 (+/ -3.2) years (range: 0.1-13.4) and mean (+/-SD) HbA(1) 11.1% (+/-2.2) ( range: 6.5-18.2), Cardiovascular autonomic function was studied by fou r heart rate (HR) tests using a computerized system of HR monitoring, As a group, diabetic children had higher mean HR (p = 0.0004) and redu ced max/min HR ratio while standing (p=0.001), compared with the contr ol children, HR ratio while standing was the only variable related to diabetes duration (r = -0.20, p=0.018), while no correlation of HR var iables with glycaemic control was found, Twenty diabetic children (15. 5%) had one abnormal HR test. Ten diabetic children (7.7%) demonstrate d abnormality in two or more HR tests, When compared with the other di abetic children in the cohort, these ten children were found to be you nger in age (mean age: 9.4 vs 12.0 yr, p=0.05), but did not otherwise differ in terms of diabetes duration or glycaemic control, No pubertal or sex effect in the development of diabetic autonomic neuropathy was detected, These findings suggest that autonomic function may be impai red early in childhood diabetes, independent of the duration of the di sease or the quality of glycaemic control.