QTc interval prolongation and QTc dispersion in children and adolescents with type 1 diabetes.
OBJECTIVE
To evaluate whether QT interval, QT interval corrected for heart rate (QTc), and QTc dispersion changes are already present in children and adolescents with diabetes.


METHODS
QT interval, QTc, and QTc dispersion were measured on a 12-lead surface electrocardiogram in 60 children and adolescents with stable type 1 diabetes and in 63 sex- and age-matched control subjects. Differences were evaluated by using the Kolmogorov-Smirnov Z test. The number of patients with QTc > 440 ms was compared in the two groups. The possible influence of age, sex, diabetes duration, and glycosylated hemoglobin (HbA(1c)) was examined by using Spearman correlation analysis.


RESULTS
Diabetic children had significantly longer QTc intervals and a significantly larger QTc dispersion. The number of individuals with a QTc >440 ms was significantly higher in the diabetic group (14/60) than in the control group (2/63). The effect of age on R-R interval and QTc dispersion in healthy children was less pronounced in children with diabetes. HbA(1C) values did not significantly correlate with any of the parameters.


CONCLUSIONS
QTc prolongation and a larger QTc dispersion are already present in a significant proportion of children and adolescents with diabetes.
Suys
Bert E
BE
Department of Pediatrics, University Hospitals, Antwerp and Ghent, Belgium.
Huybrechts
Sophie J A
SJ
De Wolf
Daniel
D
Op De Beeck
Lieve
L
Matthys
Dirk
D
Van Overmeire
B
B
Du Caju
Marc V l
MV
Rooman
Raoul P A
RP
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001342:Autonomic Nervous System Diseases / Q000150:complications* / Q000175:diagnosis; D001530:Belgium / Q000453:epidemiology; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000150:complications*; D003929:Diabetic Neuropathies / Q000150:complications* / Q000175:diagnosis; D005260:Female; D006801:Humans; D008133:Long QT Syndrome / Q000453:epidemiology* / Q000209:etiology*; D008297:Male; D012737:Sex Factors; D018709:Statistics, Nonparametric