Conclusion
This review looked to see if there is a significant association between the presence of a diagonal ear lobe crease (DELC) and coronary artery disease (CAD). We found that DELC is associated with CAD independently of other known cardiovascular risk factors including age and that patients with DELC appear to have an increased risk of CAD (OR 4.61) and this may be higher for patients with bilateral DELC. The variety of groups included in the selected studies suggest that this finding is relevant to the wider population. The sign does not have sufficient specificity or sensitivity to be used as a diagnostic test but instead it should be considered as a risk marker. For this reason we believe it is an important quick sign for clinicians to be aware of particularly those who more frequently examine ears. Histology studies have also indicated a feasible mechanism for atherosclerosis to cause DELC and explain this finding.