Evaluation of the relationship between diagonal earlobe crease and coronary artery disease in postmortem cases

Cardiovascular diseases are the most common cause of morbidity and mortality today. Frank's Sign can be defined as a diagonal earlobe crease (DELC) that starts from the tragus and extends from top to bottom, medially to laterally, and front to back. Previous studies have indicated that Frank's Sign may be associated with coronary artery disease (CAD). This study aimed to evaluate the relationship between DELC and coronary artery stenosis by retrospectively examining images from 287 consecutive autopsies conducted at the Department of Forensic Medicine at Fırat University Faculty of Medicine in the years 2021-2022, along with toxicological/histopathological reports and records indicating the cause of death. Data were collected and analyzed regarding the subjects' gender, age, height, weight, BMI, heart weight, presence (none, unilateral (right/left), and bilateral) and degree of DELC (Grade 1, 2a, 2b, 3), presence and degree of coronary artery sclerosis (none, insignificant: <25%, mild: 25-50%, moderate: 50-70%, severe: >70%), history of coronary stent/bypass, and cause of death (CAD, non-CAD cardiovascular diseases, other natural diseases, trauma). The subjects were 80.5% male and 19.5% female, with ages ranging from 18 to 88 years and an average age of 46.4±17.45 years. When natural deaths were considered separately, CAD constituted 54%. The male/female ratio in deaths due to cardiovascular diseases was higher (5.7:1) compared to the general sample group (4.12:1). Cases with a BMI≥25 accounted for 63.1%. The average heart weight was 381.4±111.0 grams for the entire sample group and 466.5±102.48 grams for deaths due to CAD. The frequency of DELC was observed at 52.6% (bilateral 40.1%, unilateral 12.6%), with 52.8% in males and 51.8% in females, and 87.8% in deaths due to CAD. Sensitivity for DELC was found to be 0.84; specificity: 0.80; positive predictive value (ppv): 0.81; negative predictive value (npv): 0.83, with sensitivity and ppv increasing with age while specificity and npv decreased with age. The predictive power and discriminative capacity of DELC for coronary artery stenosis (narrowing >25%) were assessed using the ROC curve; AUC: 0.828 (0.778-0.879) with a cut-off value of 1.5 (Grade 2a, 2b, and 3). Logistic regression analyses revealed that in univariate analysis, the Odds Ratio (OR) was; for age: 1.333, heart weight: 1.012, BMI=25-30: 2.292, BMI>30: 6.507, CAD: 10.705, coronary artery narrowing (>%25): 21.582; in multivariate analysis, OR was; for age: 1.100, BMI>30: 5.941, CAD: 8.209. The study concluded that DELC could be used as a simple, cost-effective, and easily applicable physical examination finding to determine the risk of CAD. These findings will lay the groundwork for future research and will guide clinical practice in terms of early diagnosis and treatment. In order to definitively determine the mechanism underlying the relationship between DELC and CAD, it would be beneficial to support it with prospective studies covering larger populations.