Association between triglyceride-glucose body mass index and future risk of arthritis in individuals with cardiovascular-kidney-metabolic syndrome stages 0–3: A national prospective cohort study

Cardiovascular-kidney-metabolic (CKM) syndrome encompasses interrelated cardiovascular, renal and metabolic disorders. Arthritis is linked to CKM multimorbidity, but the association between triglyceride-glucose body mass index (TyG-BMI), a surrogate marker of insulin resistance and incident arthritis across the CKM spectrum remains unclear. We analyzed data from the CHARLS cohort, including 5018 participants aged ≥45 years with CKM stages 0 to 3. Analytical approaches included multivariable logistic regression, restricted cubic splines, stratified and mediation analyses. Incident arthritis was defined by self-reported physician diagnosis, without confirmation via medical records. During follow-up, 2307 participants (45.97%) developed incident arthritis. Each one-standard-deviation increase in triglyceride-glucose body mass index (triglyceride-glucose body mass index) was associated with an 11% higher risk of arthritis (odds ratio [OR] = 1.11, 95% confidence interval [CI]: 1.04-1.19), with an approximately linear positive dose-response trend. The association appeared stronger in participants with sleep duration <7 hours (OR = 1.19, 95% CI: 1.08-1.31) and those at CKM stage 1 (OR = 1.57, 95% CI: 1.20-2.05). Exploratory mediation analyses suggested negative mediating roles of HDL-C and, marginally, BUN. Triglyceride-glucose body mass index exhibited an independent positive association with incident arthritis across CKM stages 0 to 3 and may serve as a practical indicator for early risk stratification.