QTc interval prolongation is a predictor of future strokes in patients with type 2 diabetes mellitus.
OBJECTIVE
QTc interval prolongation is a predictor of cardiovascular morbidity and mortality in general populations and in patients with diabetes. The aim of this study was to investigate the predictors of stroke in patients with type 2 diabetes, with particular emphasis on the independent role of QT interval parameters.


METHODS
We carried out a long-term follow-up study with 471 type 2 diabetics. Several clinical, laboratory, ECG, and echocardiographic variables were recorded at baseline. Predictive factors for stroke were evaluated by Kaplan-Meier estimation of survival curves and by univariate and multivariate Cox survival analyses.


RESULTS
After a median follow-up of 57 months (range, 2 to 84 months), 40 incident strokes were observed. QTc interval prolongation (>or=470 ms1/2) was an independent predictor of stroke, with adjusted hazard ratios ranging from 2.2 to 2.9 (95% confidence intervals, 1.1 to 6.0). Other independent factors associated with stroke were older age; the presence of cerebrovascular disease at baseline; increased 24-hour proteinuria, serum triglycerides, and left ventricular mass; and decreased high-density lipoprotein cholesterol. Excluding patients with previous cerebrovascular disease from the analysis did not change the results significantly.


CONCLUSIONS
QTc interval prolongation is a predictor of future stroke in patients with type 2 diabetes. Intervention studies are needed to assess whether this factor could be modified.
Cardoso
Claudia R L
CR
Department of Internal Medicine, Clementino Fraga Filho University Hospital, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. claudiacardoso@hucff.ufrj.br
Salles
Gil F
GF
Deccache
Waldemar
W
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000503:physiopathology*; D003928:Diabetic Nephropathies / Q000150:complications / Q000175:diagnosis; D018572:Disease-Free Survival; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000150:complications / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012307:Risk Factors; D020521:Stroke / Q000209:etiology*; D016019:Survival Analysis; D013995:Time