The C-reactive protein-albumin-lymphocyte (CALLY) index as a predictor of mortality in patients undergoing carotid artery stenting.

BACKGROUND

Accurate risk stratification remains important in patients undergoing carotid artery stenting (CAS). The C-reactive protein-albumin-lymphocyte (CALLY) index integrates inflammatory, nutritional, and immunological parameters; however, data regarding its prognostic value after CAS remain limited.

OBJECTIVE

To evaluate the association between the CALLY index and 30-day all-cause mortality in patients undergoing CAS and to assess its discriminatory performance.

METHODS

This retrospective observational study included 436 patients who underwent CAS at a tertiary care center between January 1, 2022, and January 1, 2026. The CALLY index was calculated as albumin (g/dL) × lymphocyte count (10⁹/L) / C-reactive protein (mg/L) using preprocedural laboratory measurements. The primary outcome was 30-day all-cause mortality. CALLY-specific analyses were performed as complete-case analyses in 339 patients with available CALLY values. Discriminatory performance was assessed using receiver operating characteristic curve analysis. Because untransformed CALLY did not satisfy the linearity assumption for logistic regression, natural-log-transformed CALLY [ln(CALLY)] was used in a parsimonious multivariable model adjusted for creatinine.

RESULTS

Eleven of 436 patients (2.5%) died within 30 days. All 11 deaths had available CALLY values; therefore, CALLY-specific analyses included 339 patients (11 deaths and 328 survivors). The CALLY index yielded an area under the curve of 0.798 (95% CI, 0.642-0.953). The data-derived cutoff of CALLY ≤ 2.65 identified using the Youden index had a sensitivity of 72.73% (95% CI, 39.03%-93.98%) and a specificity of 81.71% (95% CI, 77.09%-85.74%). In multivariable analysis, ln(CALLY) was associated with 30-day all-cause mortality (OR, 0.379; 95% CI, 0.225-0.638; P<.001), whereas creatinine was not statistically significant (OR, 1.308; 95% CI, 0.636-2.690; P=.465). The model had an AUC of 0.804 and a McFadden R² of 0.175.

CONCLUSION

Lower CALLY index values were associated with 30-day all-cause mortality after CAS and showed potentially useful discriminatory ability. However, only 11 deaths occurred, resulting in considerable uncertainty around the performance estimates. The findings should therefore be considered exploratory, and the prognostic performance and data-derived cutoff require validation in larger independent cohorts before clinical application.