Objective: To determine whether T-wave axis on the resting electrocardiogram (ECG) is associated with coronary artery calcification (CAC) score, a measurement of coronary atherosclerosis, in older adults.
Methods: The sample consisted of 2004 adults aged 66 and over participating in the prospective, population-based Age-Gene/Environment Susceptibility-Reykjavik Study. The cohort was divided into gender-stratified quartiles based upon Agatston CAC score derived from computerized tomography. Frontal T-axis deviation from 45 degrees was assessed using surface ECG. Statistical analysis was performed with Tobit regression models adjusted for demographic and cardiovascular risk factors.
Results: In the entire study population, T-axis deviation from 45 degrees was significantly associated with increasing CAC score in men (p<0.001) and women (p=0.03). In men without clinically recognized coronary heart disease (CHD), the association with CAC score remained statistically significant (p=0.02). This association was significant among women without CHD once male CAC cut points were used (p=0.05).
Conclusion: An abnormal T-wave axis is associated with an increasing CAC score in this population of Icelandic older adults. This association remains in the subgroup of subjects without clinical CHD.