Early repolarization pattern in the general population: Prevalence and associated factors.

OBJECTIVES: To evaluate the prevalence of early repolarization pattern (ERP) in the general rural Chinese population and identify the contributing risk factors.

METHODS: A cross-sectional study of 11,956 permanent residents of Liaoning Province ≥35y of age was conducted between January and August 2013 (response rate 85.3%). ERP was diagnosed if there was J-point elevation of ≥0.1mV in ≥2 leads in the inferior (II, III, aVF) or lateral (I, aVL, V4-6 ) territory, or both. Risk factors for ERP were evaluated with a stepwise logistic regression analysis.

RESULTS: The overall prevalence of ERP was 1.3%, and it was higher in men than women (2.6 vs. 0.2%, P<0.001), decreasing with increasing age. Percent of ERP positive in lateral leads, inferior, and both was 73.0%, 15.3%, and 11.7%, respectively. Stepwise logistic regression demonstrated that independent clinical factors for ERP included age (odds ratio [OR] 0.68; P<0.001), male sex (OR 17.09; P<0.001), systolic blood pressure (SBP) (OR 0.77; P=0.022), stroke (OR 0.14; P=0.055), RR interval (OR 1.27; P=0.001), QTc interval (OR 0.76; P=0.008), QRS duration (OR 0.67; P=0.001), Cornell voltage (OR 0.28; P<0.001), and Sokolow-Lyon voltage (OR 2.03; P<0.001).

CONCLUSIONS: Although the prevalence of ERP in general rural Chinese population is low, younger age, male sex, lower SBP, non-stroke history, longer RR interval, shorter QTc interval, shorter QRS duration, lower Cornell voltage, and higher Sokolow-Lyon voltage are independent risk factors.