Incidence and risk factors of prolonged QTc interval in type 1 diabetes: the EURODIAB Prospective Complications Study.
OBJECTIVE
Corrected QT (QTc) prolongation is predictive of cardiovascular mortality in both the general and diabetic populations. As part of the EURODIAB Prospective Complication Study, we have assessed the 7-year incidence and risk factors of prolonged QTc in people with type 1 diabetes.


METHODS
A total of 1,415 type 1 diabetic subjects, who had normal QTc at baseline, were reanalyzed after the 7-year follow-up period. QTc >0.44 s was considered abnormally prolonged.


RESULTS
Cumulative incidence of prolonged QTc was 18.7%, which is twofold higher in women than in men (24.5 vs. 13.9%, P < 0.0001). At the baseline examination, incident cases were older and less physically active than nonincident cases, had higher mean values of systolic blood pressure and HDL cholesterol, and had higher frequencies of hypertension, coronary heart disease, and distal symmetrical polyneuropathy. In multivariate logistic regression analyses, female sex and higher values of A1C and systolic blood pressure were associated with the risk of prolonged QTc, whereas physical activity and BMI within the range of 21.5-23.2 kg/m2 were protective factors. In women, association with modifiable factors, particularly BMI, was stronger than in men.


CONCLUSIONS
In type 1 diabetic subjects from the EURODIAB cohort, female sex, A1C, and systolic blood pressure are predictive of prolonged QTc, whereas physical activity and BMI within the range of 21.5-23.2 kg/m2 play a protective role. These findings are clinically relevant, as they may help to identify subjects at higher risk for prolonged QTc, as well as provide potential targets for risk-lowering strategies.
Giunti
Sara
S
Department of Internal Medicine, University of Torino, I-10126 Torino, Italy.
Bruno
Graziella
G
Lillaz
Emma
E
Gruden
Gabriella
G
Lolli
Valentina
V
Chaturvedi
Nish
N
Fuller
John H
JH
Veglio
Massimo
M
Cavallo-Perin
Paolo
P
D000328:Adult; D015992:Body Mass Index; D016757:Death, Sudden, Cardiac / Q000453:epidemiology; D003922:Diabetes Mellitus, Type 1 / Q000401:mortality / Q000503:physiopathology*; D003925:Diabetic Angiopathies / Q000453:epidemiology* / Q000401:mortality; D005260:Female; D005500:Follow-Up Studies; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D015994:Incidence; D008133:Long QT Syndrome / Q000453:epidemiology* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012727:Sex Characteristics; D016019:Survival Analysis; D013599:Systole
D006442:Glycated Hemoglobin