Relation of Early Repolarization (J Point Elevation) to Mortality in Blacks (from the Jackson Heart Study)

Conflicting data exist regarding the associations of early repolarization (ER) with electrocardiogram (ECG) and clinical outcomes in blacks. We examined the association of ER defined by J point elevation (JPE) and all-cause mortality, and heart failure (HF) hospitalization in blacks in the Jackson Heart Study (JHS) cohort. We included JHS participants with ECGs from the baseline visit coding JPE and excluded participants with paced rhythms or QRS duration ≥120 ms. We compared the cumulative incidence of 10-year all-cause mortality and 8-year HF hospitalization by presence of JPE ≥0.1 mV in any ECG lead at baseline using Kaplan-Meier estimates and multivariable Cox models. Of the 4,978 participants, 1,410 (28%) had JPE at baseline: anterior leads 97.8%, lateral leads 8.3%, and inferior leads 2.9%. Compared with participants without JPE, those with JPE were younger, more likely to be male and current smokers, and less likely to have hypertension. Over a median follow-up of 8 years, there were no significant differences in the cumulative incidence or multivariable-adjusted hazards of all-cause mortality or HF hospitalization in participants with and without JPE in any lead (adjusted hazard ratio 0.97, 95% confidence interval 0.89 to 1.52, and adjusted hazard ratio 1.18, 95% confidence interval 0.9 to 1.54, respectively). Of the 2,523 participants who completed Exam 3 without JPE at baseline, 246 (10%) developed JPE over follow-up. In conclusion, JPE on ECG was not associated with long-term mortality or HF hospitalization in a large prospective black community cohort, suggesting that ER may represent a benign ECG finding in blacks.