Objective:

To evaluate the prognostic value of the Geriatric Nutritional Risk Index (GNRI) across CKM stages 1–4 and in high-risk patients undergoing percutaneous coronary intervention (PCI).

Approach:

• Discovery Phase: Utilized NHANES data from 16,074 adults with CKM syndrome to assess the association between GNRI and all-cause mortality.
• Validation Phase: Analyzed an external cohort of 2,401 CKM Stage 4 patients undergoing PCI to evaluate GNRI's predictive performance for major adverse cardiovascular events (MACE).

Key Findings:

• In the discovery cohort, Q1 of GNRI was associated with higher hazards of all-cause mortality (HR 1.58; 95% CI 1.32–1.89) and cardiovascular mortality (HR 2.13; 95% CI 1.55–2.93) compared to Q4.
• Each 1-unit increase in GNRI correlated with a lower hazard of all-cause mortality (HR 0.95; 95% CI 0.94–0.97).
• In the validation cohort, Q1 vs. Q4 conferred a significantly increased risk of MACE (HR 2.52; 95% CI 2.03–3.13).
• Adding GNRI to a base clinical model improved Harrell's C-index for MACE (Δ +0.048, P < 0.001).

Interpretation:

Limitations:

• The study primarily focuses on GNRI without considering other potential prognostic factors.
• The findings may not be generalizable beyond the studied populations.

Conclusion:

GNRI provides clinically meaningful incremental risk discrimination in high-risk CKM Stage 4 patients undergoing PCI.