C ‐Reactive Protein–Triglyceride–Glucose Index and Coronary Artery Calcium Progression: A Prospective Cohort Analysis

ABSTRACT Objective The C ‐reactive protein–triglyceride–glucose index (CTI) reflects systemic inflammation and insulin resistance, but its relationship with coronary artery calcium (CAC) progression remains unclear. This study examined the association between CTI and CAC progression in a longitudinal cohort. Methods Participants from the Coronary Artery Risk Development in Young Adults (CARDIA) study with CAC measurements at years 15, 20, and 25 were included. CTI was calculated from fasting blood samples at year 15 and categorized into quartiles. CAC was quantified using standardized computed tomography. CAC progression was defined as incident CAC > 0 for those with baseline CAC = 0, an annualized CAC increase ≥ 10 units for those with baseline CAC: 0–100, or an annualized percent increase ≥10% for those with baseline CAC ≥ 100. Cox proportional hazards models estimated hazard ratios (HRs), adjusting for cardiovascular risk factors. Results Among 2655 participants (mean age 40.3 ± 3.6 years; 44.7% men), 704 (26.5%) experienced CAC progression over 8.9 ± 2.0 years. After adjustment, individuals in the highest CTI quartile had a 38% higher risk of CAC progression compared with the lowest quartile (HR = 1.380; 95% CI: 1.072–1.775). Subgroup analyses by age, sex, race, body mass index, and baseline CAC status were consistent, and results remained robust after excluding participants with baseline diabetes or lipid‐lowering medication use. Conclusions Higher CTI was independently associated with increased CAC progression, supporting its potential utility as a biomarker for identifying individuals at elevated risk of subclinical atherosclerosis. Trial Registration URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00005130.