Association of the C-reactive protein-triglyceride-glucose index with incident abdominal aortic aneurysm: a prospective cohort study from the UK Biobank

Abstract:

Background and Aims Abdominal aortic aneurysm (AAA) is a life-threatening vascular disease closely associated with chronic inflammation and insulin resistance (IR). The C-reactive protein-triglyceride-glucose index (CTI), a novel composite biomarker integrating inflammatory and metabolic status, has shown prognostic value in cardiovascular diseases. However, its association with AAA risk remains unclear. This study aimed to investigate the relationship between CTI and incident AAA using data from the UK Biobank.Methods A total of 315 003 participants free of aneurysmal disease at baseline with available CTI data were included from the UK Biobank cohort. Incident AAA was defined as the primary outcome. Kaplan-Meier analysis was used to estimate the cumulative incidence of AAA across CTI levels, while multivariable regression models and restricted cubic spline (RCS) analysis were employed to evaluate the association between CTI and incident AAA risk and to assess the dose-response relationship. Subgroup and sensitivity analyses were conducted to assess the robustness of the findings.Results During a median follow-up of 16.37 years, 1 343 participants developed AAA. Kaplan-Meier curves demonstrated a progressive increase in cumulative AAA incidence across CTI quartiles. In the fully adjusted model, each standard deviation increase in CTI was associated with a 39% higher risk of AAA (HR=1.39, 95% CI=1.30-1.48). Compared with the lowest CTI quartile, participants in the highest quartile had a significantly elevated risk of AAA (HR=2.15, 95% CI=1.73-2.66; P_trend<0.001). RCS analysis revealed a significant nonlinear association between CTI and AAA risk (P_non-linear=0.008). The association was more pronounced among current or former smokers, participants with HbA1c<48 mmol/mol, and those without hypertension, diabetes, coronary heart disease, or lipid-lowering medication use (all P_interaction<0.05). Sensitivity analyses yielded consistent results.Conclusion Elevated CTI was independently associated with an increased risk of incident AAA in a dose-dependent manner. CTI may serve as a readily available biomarker for early risk identification and risk stratification of AAA.