Association between ventricular repolarization and main cardiovascular risk factors

OBJECTIVE: To assess the association between QT interval, QT dispersion and main cardiovascular risk factors in Tallinn women population aged 50-69 years. DESIGN: A random sample of Tallinn population, 302 women underwent 12-lead rest ECG, echocardiography and laboratory tests. Corrected QT interval and QT dispersion were calculated. RESULTS: The significant correlation coefficients for corrected QT interval and dispersion were observed with systolic, diastolic, pulse pressure, blood pressure value grade, heart rate, left ventricular mass index, and total cardiovascular risk grade. According to the data of multiple logistic regression, risk factors independently associated with prolonged QTc and QTD were arterial hypertension: OR 2.69, p < 0.001 and OR 3.29, p < 0.001, pulse pressure ≥ 60 mm Hg: OR 2.62, p < 0.001 and OR 3.04, p < 0.001, age > 65 years: OR 2.44, p < 0.001 and OR 1.91, p < 0.01, family history of cardiovascular disease: OR 2.02, p < 0.01 and OR 2.48, p < 0.001, left ventricular hypertrophy: OR 2.78, p < 0.001 and OR 5.29, p < 0.001. Multivariable linear regression data showed an independent association between corrected QT interval, QT dispersion and systolic blood pressure: β = 0.32, p < 0.001 and β = 0.39, p=0.003, pulse pressure: β = 0.21, p = 0.004 and β = 0.27, p < 0.001, blood pressure value grade: β = 0.35, p < 0.001 (for QT dispersion only), heart rate: β = 0.21, p < 0.001 and β = -0.19, p = 0.001, left ventricular mass index: β = 0.23, p < 0.001 and β = 0.27, p < 0.001. CONCLUSION: In Tallinn women population, electrocardiographic parameters reflecting ventricular repolarization are associated with systolic blood pressure, pulse pressure, blood pressure value grade, heart rate and left ventricular hypertrophy.