Association of early repolarization pattern with cardiovascular outcomes in middle-aged population: A cohort study

Background Large cohort studies provide conflicting evidence regarding the prognostic value of early repolarization pattern (ERP) in the general population, complicated by the complex or heterogeneous definitions of ERP applied in different studies. Hypothesis We hypothesized that ERP was associated with increased cardiovascular risk with the definition of ERP recommended by the expert consensus statements. Methods A total of 13673 middle-aged subjects from the prospective, population-based Atherosclerosis Risk in Communities (ARIC) study were included in this analysis. Cox models were used to estimate the hazard ratios (HRs) adjusted for possible confounding factors. ERP was defined as ST-segment elevation >= 0.1mV at the end of the QRS or J wave on the QRS downstroke in two or more contiguous leads. Results Compared with those without ERP, subjects with ERP had a significantly increased risk of developing sudden cardiac death (SCD) (HR, 1.48; 95% CI, 1.08-2.04) and death from coronary heart disease (CHD) (HR, 1.45; 95% CI, 1.10-1.92) after a median follow-up of 20.1 years. ERP was significantly predictive of SCD in females, whites, younger people, and subjects with relatively low cardiovascular risk. ERP with ST-segment elevation appeared to indicate poor cardiovascular outcomes. ERP was associated with an absolute risk increase of 93.3 additional SCDs per 100 000 person-years. Conclusions Our findings suggest that ERP was an independent predictor of SCD and CHD death in the middle-aged biracial population.