C-reactive protein-triglyceride-glucose index (CTI) as a predictor of chronic liver disease in adults with macrocytic anemia

Macrocytic anemia is frequently associated with liver dysfunction; however, reliable biomarkers for predicting chronic liver disease (CLD) in this population remain limited. This longitudinal study included 693 individuals with macrocytic anemia from the China Health and Retirement Longitudinal Study (CHARLS). Individuals with a mean corpuscular volume (MCV) > 100 fL were defined as having macrocytic anemia. C-reactive protein-triglyceride-glucose index (CTI) was calculated by the formula of CTI = 0.412×Ln(CRP [mg/L]) + Ln(TG [mg/dL] × FPG [mg/dL])/2. Then, the association between CTI and CLD was assessed using three sequentially adjusted Cox regression models, along with restricted cubic splines and subgroup analyses. Model 1 was unadjusted; Model 2 adjusted for demographic characteristics including age, gender, marital status, education, and BMI; Model 3 further adjusted for smoking, drinking, sleep night, and socioeconomic status (SES) based on the Model 2. Key predictors were selected by Least Absolute Shrinkage and Selection Operator (LASSO) to construct a clinical nomogram. We found that a higher CTI was linked to a greater chance of developing liver disease, which remained robust after sequential adjustment for confounders. In Model 3, the hazard ratio (HR) for CTI was 1.607 (95% confidence interval [CI]: 1.085-2.381; P = 0.018). Restricted cubic spline analysis confirmed a linear positive relationship between CTI and CLD risk. This link was consistent across different ages, genders, and lifestyles. When we built a prediction tool using CTI and other factors like age and marital status, it showed a fair ability to estimate a person's risk. CTI may serve as a simple and potentially useful indicator to identify individuals with macrocytic anemia who are at a higher risk of chronic liver disease, helping guide earlier prevention efforts.