Electrocardiographic repolarization complexity and abnormality predict all-cause and cardiovascular mortality in diabetes: the strong heart study.
Type 2 diabetes is associated with increased risk of cardiovascular (CV) and all-cause mortality. Although electrocardiographic measures of repolarization abnormality and complexity stratify risk in the general population, their prognostic value in diabetes has not been well characterized. Digital electrocardiogram (ECG) readings were acquired for 994 American Indians with type 2 diabetes. ST segment depression (STD) >/=50 micro V and rate-corrected QT interval (QTc) >460 ms were examined as measures of repolarization abnormality. The principal component analysis (PCA) of the ratio of the second to first eigenvalues of the T-wave vector (PCA ratio) (>32.0% in women and >24.6% in men) was examined as a measure of repolarization complexity on the ECG. After a mean follow-up of 4.7 +/- 1.0 years, there were 56 CV deaths and 155 deaths from all causes. In univariate analyses, STD, QTc, and the PCA ratio predicted CV and all-cause mortality. After multivariate adjustment for age, sex, and other risk factors, STD (hazard ratio 3.68, 95% CI 1.70-7.96) and PCA ratio (2.61, 1.33-5.13) remained predictive of CV mortality and both STD (2.36, 1.38-4.02) and QTc (2.03, 1.32-3.12) predicted all-cause mortality. Computerized ECG measures of repolarization abnormality and complexity predict CV and all-cause mortality in type 2 diabetes, supporting their use to identify high-risk individuals with diabetes.
Okin
Peter M
PM
Department of Medicine, Division of Cardiology, Cornell Medical Center, New York, New York, USA. pokin@med.cornell.edu
Devereux
Richard B
RB
Lee
Elisa T
ET
Galloway
James M
JM
Howard
Barbara V
BV
D000704:Analysis of Variance; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000401:mortality*; D002423:Cause of Death; D003924:Diabetes Mellitus, Type 2 / Q000401:mortality*; D003925:Diabetic Angiopathies / Q000453:epidemiology / Q000401:mortality*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007198:Indians, North American; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015995:Prevalence; D017741:Survivors; D013997:Time Factors
D008055:Lipids