The Cardiovascular-Kidney-Metabolic (CKM) syndrome is a newly defined condition that explains how heart, kidney, and metabolic disorders (like diabetes and obesity) are interconnected. Patients with CKM are at a particularly high risk of stroke. The following study, published in the BMC Cardiovascular Disorders, proposes a new CTI index for better predictability of stroke in CKM patients. 

Data was collected from China Health and Retirement Longitudinal Study (CHARLS), a large, nationally representative cohort, which included 5,767 adults. Anyone with a prior stroke at baseline, missing essential lab/clinical data, or incomplete follow-up was excluded. Participants were divided into stages 1-3 of CKM. Stage 0–1 consisted of early risk, no advanced metabolic or organ damage, and patients. Stage 2–3 included moderate to advanced metabolic dysfunction and subclinical heart/kidney injury in patients.

Using this data, the CTI (C-reactive protein–TyG index) was calculated. This index took into account the C-reactive protein, a marker of systemic inflammation, and the TyG index, a marker of insulin resistance. For comparison, METS-IR was also calculated. The outcome targeted for this study was the incidence of stroke during 9 years of follow-up. This data was obtained by self-reported physician diagnosis. 

Analysis of this data revealed the major risk groups, which included older people, those with high BMI,  blood pressure, and worse metabolic risk factors, show more prevalence of diabetes, hypertension, and CKM stage 2–3. This indicated that high CTI reflects a higher cardiometabolic burden. Each 1-unit increase in CTI was associated with approximately 50% higher risk of stroke (HR ≈ 1.5). Restricted cubic spline models showed a linear, positive relationship between CTI and stroke risk. This index also outperformed traditional predictors like TyG, METS-IR, etc.