The Geriatric Nutritional Risk Index as an Alternative to the EuroSCORE II in Estimating Cardiac Surgery Risk

Area of Science:

• Cardiology
• Geriatric Medicine
• Surgical Risk Assessment

Background:

• The Geriatric Nutritional Risk Index (GNRI) is designed to predict mortality in individuals aged 65 and older.
• Unlike many cardiac surgery risk scores, GNRI utilizes only six clinical parameters: age, height, weight, sex, albumin, and sodium levels.

Purpose of the Study:

• To evaluate the predictive performance of the GNRI for 30-day mortality in elderly patients undergoing cardiac surgery.
• To compare the predictive accuracy of GNRI against the established EuroSCORE II risk assessment tool.

Main Methods:

• A retrospective analysis of 6712 consecutive patients aged 65 or older who underwent cardiac surgery with cardiopulmonary bypass (CPB) between 2010 and 2023.
• Patients were categorized into GNRI risk classes: major (<82), moderate (82 to <92), low (92 to ≤98), and minimal (>98).
• Receiver operating characteristic (ROC) analyses were conducted to compare the predictive power of GNRI and EuroSCORE II for 30-day mortality.

Main Results:

• The GNRI demonstrated comparable predictive power for 30-day mortality to EuroSCORE II (AUC=0.75 vs. 0.71).
• After adjustment for surgical type, GNRI's predictive accuracy improved (AUC=0.77) and showed no significant statistical difference compared to EuroSCORE II (P=.6).
• The Hosmer-Lemeshow test indicated good calibration for both the GNRI and adjusted GNRI models (P=.301 and P=.619, respectively), unlike EuroSCORE II (P<.0001).

Conclusions:

• The GNRI is a reliable predictor of 30-day mortality in elderly patients undergoing cardiac surgery with CPB, performing comparably to EuroSCORE II.
• GNRI provides a significantly simplified approach to risk stratification in this patient population.