Increased QT interval dispersion predicts 15-year cardiovascular mortality in type 2 diabetic subjects: the population-based Casale Monferrato Study.
OBJECTIVE
To evaluate the predictive role of increased corrected QT (QTc) and QT interval dispersion (QTd) on all-cause and cardiovascular mortality in a large, unselected type 2 diabetic population.


METHODS
The prospective study included 1,357 type 2 diabetic patients from the Casale Monferrato Study. At baseline, QTc intervals >0.44 s and QTd intervals >0.08 s were considered abnormally prolonged. Both all-cause and cardiovascular mortality were assessed 15 years after the baseline examination.


RESULTS
During the follow-up period, 862 subjects per 12,450 person-years died. Multivariate analysis showed that the hazard ratio (HR) of cardiovascular mortality was significantly increased in subjects with prolonged QTd (1.26 [95% CI 1.02-1.55]) and was only slightly reduced after multiple adjustments. Conversely, prolonged QTc did not increase the HRs for all-cause or cardiovascular mortality.


CONCLUSIONS
Increased QTd predicts cardiovascular mortality after a long-term follow-up period in a large, unselected population of type 2 diabetic subjects.
Department of Internal Medicine, University of Turin, Turin, Italy. sara_giunti@katamail.com
Sara
S
Giunti
Gabriella
G
Gruden
Paolo
P
Fornengo
Federica
F
Barutta
Cristina
C
Amione
Giuseppe
G
Ghezzo
Paolo
P
Cavallo-Perin
Graziella
G
Bruno
D001145:Arrhythmias, Cardiac / Q000401:mortality / Q000503:physiopathology; D002318:Cardiovascular Diseases / Q000401:mortality / Q000503:physiopathology; D003924:Diabetes Mellitus, Type 2 / Q000401:mortality* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D011446:Prospective Studies