title: Racial Differences in Electrocardiographic Characteristics and Prognostic Significance in Whites Versus Asians.
abstract: Racial differences in electrocardiographic (ECG) characteristics and prognostic significance among Whites and Asians are not well described.
  
  
  
  We studied 2677 White Framingham Heart Study participants (57% women) and 2972 Asian (64% women) Singapore Longitudinal Aging Study participants (mean age 66 years in both) free of myocardial infarction or heart failure. Racial differences in ECG characteristics and effect on mortality were assessed. In linear regression models, PR interval was longer in Asians compared with Whites (multivariable-adjusted β±SE 5.0±1.4 ms in men and 6.6±0.9 ms in women, both P<0.0006). QT interval was shorter in Asian men (β±SE -6.2±1.2 ms, P<0.0001) and longer in Asian women (β±SE 3.6±0.9 ms, P=0.02) compared to White men and women, respectively. Asians had greater odds of having ECG left ventricular hypertrophy (LVH) compared with Whites (odds ratio [OR] 3.56, 95% confidence interval [CI] 1.36-9.35 for men, OR 1.93, 95% CI 1.35-2.76 for women, both P<0.02). Over a mean follow-up of 11±3 years in Framingham and 8±3 years in Singapore, mortality rates were 24.5 and 13.4 per 1000 person-years among Whites and Asians, respectively. In Cox models, the presence of LVH had a greater effect on all-cause mortality in Asians compared with Whites (hazard ratio [HR] 2.66, 95% CI 1.83-3.88 vs HR 1.30, 95% CI 0.90-1.89, P for interaction=0.02).
  
  
  
  Our findings from two large community-based cohorts show prominent race differences in ECG characteristics between Whites and Asians, and also suggest a differential association with mortality. These differences may carry implications for race-specific ECG reference ranges and cardiovascular risk.
authors.affiliation: Cardiovascular Medicine Section, Department of Medicine, Boston University School of Medicine, Boston, MA.
authors.forename: Rajalakshmi
authors.initials: R
authors.lastname: Santhanakrishnan
authors.affiliation: Data Coordinating Center, Boston University School of Public Health, Boston, MA.
authors.forename: Na
authors.initials: N
authors.lastname: Wang
authors.affiliation: Department of Mathematics and Statistics, Boston University, Boston, MA National Heart, Lung, and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA.
authors.forename: Martin G
authors.initials: MG
authors.lastname: Larson
authors.affiliation: Cardiovascular Medicine Section, Department of Medicine, Boston University School of Medicine, Boston, MA National Heart, Lung, and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA.
authors.forename: Jared W
authors.initials: JW
authors.lastname: Magnani
authors.affiliation: Cardiovascular Medicine Section, Department of Medicine, Boston University School of Medicine, Boston, MA Section of Preventive Medicine and Epidemiology, Boston University School of Medicine, Boston, MA National Heart, Lung, and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA.
authors.forename: Ramachandran S
authors.initials: RS
authors.lastname: Vasan
authors.affiliation: Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University, Nashville, TN.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Wang
authors.affiliation: Department of Cardiology, National Heart Centre Singapore, Singapore.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Yap
authors.affiliation: Duke-NUS Graduate Medical School, Singapore.
authors.forename: Liang
authors.initials: L
authors.lastname: Feng
authors.affiliation: Geriatric Medicine, Ng Teng Fong Hospital, Singapore.
authors.forename: Keng B
authors.initials: KB
authors.lastname: Yap
authors.affiliation: Department of Cardiology, Khoo Teck Puat Hospital, Singapore.
authors.forename: Hean Y
authors.initials: HY
authors.lastname: Ong
authors.affiliation: Yong Loo Lin School of Medicine, Singapore.
authors.forename: Tze P
authors.initials: TP
authors.lastname: Ng
authors.affiliation: Cardiovascular Research Institute, National University Health System, Singapore Christchurch Heart Institute, University of Otago, Christchurch, New Zealand.
authors.forename: Arthur Mark
authors.initials: AM
authors.lastname: Richards
authors.affiliation: Department of Cardiology, National Heart Centre Singapore, Singapore Duke-NUS Graduate Medical School, Singapore.
authors.forename: Carolyn S P
authors.initials: CS
authors.lastname: Lam
authors.affiliation: National Heart, Lung, and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA Cardiovascular Research Center and the Division of Cardiology, Department of Medicine, Massachusetts General Hospital, Boston, MA jho1@partners.org.
authors.forename: Jennifer E
authors.initials: JE
authors.lastname: Ho
mesh_terms: D000200:Action Potentials; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D002318:Cardiovascular Diseases / Q000175:diagnosis* / Q000208:ethnology* / Q000401:mortality / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D054624:Health Status Disparities; D006329:Heart Conduction System / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000175:diagnosis / Q000208:ethnology; D053208:Kaplan-Meier Estimate; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D008404:Massachusetts / Q000453:epidemiology; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors; D012846:Singapore; D013997:Time Factors; D044465:White People
keywords: electrocardiography; epidemiology; left ventricular hypertrophy; mortality; race