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

The Geriatric Nutritional Risk Index (GNRI) was introduced to predict mortality in elderly people (age ≥ 65 years). In contrast to common risk scores for cardiac surgery, the GNRI relies on just 6 clinical parameters: age, height, weight, sex, albumin, and sodium.

This study presents a large single-centre, retrospective analysis of all consecutive patients ≥ 65 years who underwent cardiac surgery using cardiopulmonary bypass (CPB) between 2010 and 2023. Patients were stratified according to GNRI risk classes: major risk (<82), moderate risk (82 to <92), low risk (92 to ≤98), and minimal risk (>98). Receiver operating risk analyses were performed to compare the predictive power of 30-day mortality of GNRI versus the EuroSCORE II.

In total, 6712 patients were included: 52 (0.8%) patients were at major risk, 233 (3.5%) patients were at moderate risk, 506 (7.5%) patients were at low risk, and 5921 (88.2%) patients were at minimal risk. The GNRI had the same predictive power for 30-day mortality as the EuroSCORE II (AUC = 0.75 vs AUC = 0.71, P = .051). Notably, when adjusted for the type of surgery, GNRI reached an AUC = 0.77 and did statistically not differ from the EuroSCORE II (P = .6). The Hosmer-Lemeshow test indicated good calibration for both the GNRI model (P = .301) and the adjusted GNRI model (P = .619) and revealed P < .0001 for the EuroSCORE II.

The GNRI demonstrates predictive power for all-cause 30-day mortality comparable to the EuroSCORE II in a real-world patient cohort. GNRI offers a substantial simplification of risk estimation in patients undergoing cardiac surgery with CPB.