Introduction:
The C-reactive protein-albumin-lymphocyte (CALLY) index represents a novel composite biomarker integrating inflammatory, nutritional, and immune parameters. We aim to examine the relationship between CALLY index and chronic kidney disease (CKD) prevalence.

Material and methods:
This cross-sectional analysis utilized data from the National Health and Nutrition Examination Survey. CKD was defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73m² and/or urinary albumin-to-creatinine ratio (UACR) ≥30 mg/g. Multivariable logistic regression and restricted cubic spline (RCS) analyses assessed the relationship between CALLY index and the CKD prevalence. Among CKD patients, Cox proportional hazards models evaluated CALLY index’s associations with all-cause and cardiovascular mortality.

Results:
Among the 26996 participants, 4997 individuals were diagnosed with CKD. Participants with CKD demonstrated lower CALLY index values compared to those without CKD. Multivariable logistic regression indicated compared to the lowest quartile, the highest quartile showed 29.5% reduced CKD risk (OR: 0.705, 95% CI: 0.589-0.845, p<0.001). RCS model demonstrated a significant L-shaped association between CALLY index and the CKD prevalence. Among CKD patients, higher CALLY index significantly predicted better survival outcomes for both all-cause and cardiovascular mortality.

Conclusions:
The CALLY index demonstrates inverse associations with CKD risk and mortality, suggesting its potential utility as a comprehensive biomarker for CKD risk stratification and prognosis assessment.