Atherosclerosis in Early Rheumatoid Arthritis Patients Using Atherogenic Index of the Plasma and Carotid Intima Media Thickness

Atherogenic Index of Plasma and Carotid Intima-media Thickness as Predictors of Preclinical Atherosclerosis in Early Rheumatoid Arthritis Patients Younger Than 50 Years of Age

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease primarily affecting the peripheral joints, yet its extra-articular burden particularly on the cardiovascular (CV) system has emerged as its most consequential long-term complication . Cardiovascular disease (CVD) accounts for 40% of all deaths in RA patients, making it the leading cause of mortality .This excess CV risk is estimated to be 1.5 to 2 times higher than in the general population .The overall CV risk conferred by RA has been linked in magnitude to that of diabetes mellitus, underscoring RA as an independent cardiovascular risk factor formally recognised in the 2021 European Society of Cardiology Guidelines on CVD prevention .

In this context, the non-invasive detection of preclinical atherosclerosis before the onset of clinical CV events has become clinical priority. Carotid intima-media thickness (CIMT), measured by high-resolution B-mode ultrasonography, is a well-validated surrogate marker of early structural arterial wall changes that independently predicts future myocardial infarction and stroke .Multiple studies have documented significantly elevated CIMT in RA patients compared with age- and sex-matched controls; studies found higher CIMT values across all age groups in RA, with values increasing in proportion to disease severity as assessed by the Disease Activity Score in 28 joints .

The atherogenic index of plasma (AIP) defined as the base-10 logarithm of the triglyceride-to-HDL-cholesterol ratio has emerged as a calculated composite biomarker reflecting lipoprotein particle atherogenicity, particularly the preponderance of small, dense LDL particles .A high AIP (>0.21) has been independently associated with major adverse cardiovascular events beyond the predictive capacity of conventional lipid panels .

Inclusion Criteria:

for cases (Rheumatoid Arthritis patients)

• Patients fulfilling the 2010 American College of Rheumatology / European League Against Rheumatism (ACR/EULAR) classification criteria for RA
• Disease duration of ≤6 months from the onset of symptoms (early RA)

For Controls (Healthy Subjects):

• Healthy volunteers aged 18 to 49 years with no known inflammatory, autoimmune, or chronic disease.
• Age- and sex-matched (within ±2 years) to case subjects

Exclusion Criteria:

• Established cardiovascular disease (coronary artery disease, prior myocardial infarction, stroke, peripheral arterial disease, or heart failure).
• Diabetes mellitus, Hypertension, and Dyslipidaemia on lipid-lowering therapy (statins, fibrates, niacin, or omega-3 agents), as these agents directly modify AIP values.
• Chronic kidney disease (eGFR <60 mL/min/1.73 m²) and Hepatic disease, thyroid dysfunction, or any other significant endocrine disorder.
• Pregnancy or lactation.
• Other connective tissue diseases (systemic lupus erythematosus, systemic sclerosis, Sjögren's syndrome).
• Other inflammatory arthropathies (psoriatic arthritis, ankylosing spondylitis, reactive arthritis).