title: Cornell product left ventricular hypertrophy in electrocardiogram and the risk of stroke in a general population.
abstract: Left ventricular hypertrophy (LVH), assessed by ECG, is associated with an increased risk for cardiovascular events among hypertensive subjects. We evaluated the risks of LVH in a Japanese general population including normotensive and prehypertensive subjects. We measured ECG and blood pressure in 10 755 subjects at baseline. The Cornell product (CP) and Sokolow-Lyon (SL) voltage were calculated as markers of LVH (CP >or=2440 mm x ms and SL voltage >or=38 mm). Follow-up was performed for 10 years, and the incidence of stroke and myocardial infarction was evaluated. The prevalence of CP-LVH was 2.7% for normotensives, 5.2% for prehypertensives, and 11.0% for hypertensives, and the prevalence of SL-LVH was 5.0%, 8.2%, and 15.2%, respectively. In all of the subjects, CP-LVH and SL-LVH were both predictors of stroke (CP-LVH: hazard risk: 1.62, 95% CI: 1.19 to 2.20, P=0.002; SL-LVH: hazard risk: 1.29, 95% CI: 0.98 to 1.71, P=0.07) after adjustment for confounding factors but were not predictors of myocardial infarction. The adjusted hazard ratio of CP-LVH predicting stroke was especially high in the normotensives (hazard risk: 7.53; 95% CI: 3.39 to 16.77). In the normotensives, diabetes mellitus and hyperlipidemia were significant determinants of CP-LVH but not of SL-LVH. In all of the hypertensive subgroups (normotensives, prehypertensives, and hypertensives), the c-statistic for the equation predicting stroke increased when CP-LVH was added to the model but not when SL-LVH was added. In conclusion, both CP-LVH and SL-LVH are risk factors for stroke in the Japanese general population. CP-LVH is related to glucose abnormality, and its predictive value for stroke is seen even in normotensives and prehypertensives.
authors.affiliation: Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University, School of Medicine 3311-1, Yakushiji, Shimotsuke, Tochigi 329-0498, Japan. george@jichi.ac.jp
authors.forename: Joji
authors.initials: J
authors.lastname: Ishikawa
authors.forename: Shizukiyo
authors.initials: S
authors.lastname: Ishikawa
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Kabutoya
authors.forename: Tadao
authors.initials: T
authors.lastname: Gotoh
authors.forename: Kazunori
authors.initials: K
authors.lastname: Kayaba
authors.forename: Joseph E
authors.initials: JE
authors.lastname: Schwartz
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Pickering
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Shimada
authors.forename: Kazuomi
authors.initials: K
authors.lastname: Kario
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000503:physiopathology; D017379:Hypertrophy, Left Ventricular / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology*; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology / Q000503:physiopathology; D011237:Predictive Value of Tests; D011379:Prognosis; D012307:Risk Factors; D012680:Sensitivity and Specificity; D020521:Stroke / Q000453:epidemiology* / Q000208:ethnology / Q000503:physiopathology