0458: TyG-BMI Index as a Serological Biomarker for Carotid Plaque and Cardiac Function Changes in Rheumatoid Arthritis

Background/Purpose: The Triglyceride-Glucose-BMI index (TyG-BMI) is a reliable method for detecting insulin resistance (IR), with effectiveness comparable to the gold standard. Elevated TyG-BMI levels have been associated with subclinical atherosclerosis and cardiac dysfunction. Both IR and rheumatoid arthritis (RA) promote a state of hyperglycemia. Therefore, the use of TyG-BMI as a screening tool for CV risk assessment in this population is proposed, offering a practical and effective alternative for screening. For this reason, we aim to evaluate the association of the TyG-BMI Index with carotid plaque (CP), left ventricular geometry, and subclinical cardiac dysfunction in patients with RA.

Methods: A Cross-sectional, descriptive, comparative study was conducted. Patients aged 30 to 75 with RA criteria were included. Those with CV disease history were excluded. Carotid ultrasound and transthoracic echocardiogram were performed in 297 and 238 participants, respectively. CP was defined as a diffuse carotid intima-media thickness (IMT) ≥1.2 mm or focal thickness ≥0.8 mm. The echocardiographic assessment included left ventricular mass index (LVMI), relative wall thickness (RWT), tricuspid annular plane systolic excursion (TAPSE), and left ventricular ejection fraction (LVEF). Subclinical diastolic dysfunction (SDD) was defined according to the 2016 American College of Cardiology classification, and subclinical systolic dysfunction (SSD) of the left ventricle (LV) was defined as a global longitudinal strain (GLS) >-18%.

To calculate the TyG-BMI index, serum triglyceride (TG) levels, fasting blood glucose (FBG), and body mass index (BMI) were used with the following formula: TyG-BMI Index = Ln [TG (mg/dL) × FBG (mg/dL)/2] × BMI.

Participants were categorized into tertiles based on the TyG-BMI. Group distribution was evaluated using the Kolmogorov-Smirnov test. Comparisons were made using the Chi-square test, ANOVA, or Kruskal-Wallis test. A p-value ≤0.05 was considered statistically significant.

Results: Most patients with RA were women aged between 53 and 57 years. Among the 297 patients who underwent carotid ultrasound (Table 1), a higher prevalence of diabetes, hypertension, and obesity was observed in the third tertile. However, the prevalence of CP was similar across all groups and was not statistically significant.
Regarding the 238 patients who underwent transthoracic echocardiography (Table 2), a similar prevalence of CV risk comorbidities was observed. From the second tertile onward, there was an increase in the prevalence of subclinical diastolic dysfunction and concentric remodeling changes, although these differences were not statistically significant.

Conclusion: The TyG-BMI index was not associated with the presence of CP, significant changes in echocardiographic parameters. However, higher TyG-BMI levels were related to traditional CV risk comorbidities. Despite these findings, studies with larger sample sizes are needed to confirm these associations. Integrating echocardiographic and carotid ultrasound assessments into CV risk evaluation remains essential for the early detection of structural and functional abnormalities.