The correlation among QTc interval, hyperglycaemia and the impaired autonomic activity.
BACKGROUND
The QT interval reflects the duration of the intracellular action potential. Little is known on the interval QT duration in non diabetic insulin-resistant subjects.


OBJECTIVE
The aims of the current study were to evaluate the QTc interval in three groups of non diabetic insulin-resistant subjects and the possible correlation between QTc and the autonomic nervous system's activity.


METHODS
90 subjects were divided in subjects with impaired fasting glycaemia (IFG) and, by the results of OGTT, according to the criteria of ADA, in subjects with normal glucose regulation (NGR) and impaired glucose tolerance (IGT). Insulin resistance was evaluated by the homeostasis model assessment-index (HOMA-I). Heart rate variability and Qtc were calculated.


RESULTS
QTc interval is correlated with SDNN, LF n.u. and LF/HF.


CONCLUSIONS
We have observed that the QTc interval is prolonged in insulin-resistant subjects with associated impaired glucose metabolism, while no difference was reported between insulin-resistant and non insulin-resistant subjects with normal glucose regulation. We hypothesize that hyperglycaemia could play a major role than hyperinsulinemia on the QTc prolongation.
Fiorentini
Alessandra
A
UO Geriatria, Hospital of Montefiascone POC, Viterbo, Italy. fiorentini-a@libero.it
Perciaccante
Antonio
A
Valente
Rosita
R
Paris
Alberto
A
Serra
Pietro
P
Tubani
Luigi
L
D000328:Adult; D000704:Analysis of Variance; D001342:Autonomic Nervous System Diseases / Q000150:complications*; D001786:Blood Glucose / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D004562:Electrocardiography; D005260:Female; D007839:Functional Laterality; D005951:Glucose Tolerance Test / Q000379:methods; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D006943:Hyperglycemia / Q000150:complications*; D007333:Insulin Resistance / Q000502:physiology; D008133:Long QT Syndrome / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013223:Statistics as Topic; D013997:Time Factors
D001786:Blood Glucose