Epicardial Fat Thickness: A Cardiometabolic Risk Marker in Rheumatoid Arthritis.

Background: Rheumatoid arthritis (RA) is a chronic, systemic, inflammatory disorder of unknown etiology which mainly involves synovial joints. However, the corresponding systemic inflammation may result in disorders of multiple other organ systems. Several organs and organ systems are potentially involved in RA, particularly in severe diseases. The organs most involved are the lung, heart, eyes, and nervous system. Extra-articular manifestations of RA may develop even before the onset of arthritis. Emerging epidemiological evidence shows that cardiovascular disease (CVD) accounts for near about 50% of RA-associated death. Epicardial fat thickness (EFT) has recently emerged as a new marker of cardiometabolic risk. Although Epicardial fat (EF) is needed for heart muscle function, given its intrinsic inflammatory status, EFT displays the potential to serve as a therapeutic target in patients with RA.

Objectives: To evaluate EFT using echocardiography in RA patients compared to age and sex-matched control and to find the factors associated with EFT in RA patients.

Materials And Methods:  This current study was conducted in the Department of Medicine, Postgraduate Institute of Medical Education & Research. The study was conducted from November 2016 to March 2018. Patients with BMI ≥ 30 kg/m, diabetes mellitus, primary hyperlipidemia, and uncontrolled hypertension were particularly excluded. Thirty patients of age and sex-matched controls were also taken for the study. All the patients and controls selected for the study were subjected to detailed history taking and clinical examination. They were subjected to lab investigations and echocardiography. The 30 RA patients included in the study were diagnosed according to the 2010 ACR-EULAR criteria. Disease activity was measured by the disease activity score (DAS28) index.

Results:  Group 1 included 30 patients with RA and group 2 included 30 age and sex-matched controls. Pearson correlation analysis was done between EFT and other variables. Only HDL, erythrocyte sedimentation rate (ESR), high-sensitivity C-reactive protein (hS-CRP), rheumatoid factor (RF), anti-cyclic citrullinated peptide (anti-CCP), DAS28, and disease duration were found to have a significant correlation with EFT.

Conclusion:  In patients with RA, EFT, left ventricular mass, and diastolic dysfunction are increased in RA patients compared to healthy controls. Out of the conventional CVD risk factors, only HDL was associated with increased EFT in RA patients. In RA patients, DAS28, disease duration, RF, anti-CCP, and markers of inflammation (ESR, hs-CRP) were also associated with increased EFT.