Geriatric Nutritional Risk Index as a Predictor of Major Adverse Limb Events in Older Patients With Peripheral Artery Disease: A Prospective Cohort Study.

Background And Aim: The geriatric nutritional risk index (GNRI) predicts adverse outcomes in chronic diseases, but its prognostic value for major adverse limb events (MALE) in elderly patients with peripheral artery disease (PAD) remains unverified; thus, this study aimed to establish the association between GNRI and MALE.

Design: A multicenter, prospective study.

Methods: From January 2021 to August 2022, 1200 patients with PAD aged ≥ 60 years were enrolled. Patients were stratified by GNRI value (At-risk group: ≤ 98 vs. No-risk group: > 98). Data were analysed through Kaplan-Meier curves, multivariable Cox regression, restricted cubic spline (RCS) modelling, and subgroup analyses.

Results: Among 1036 completers (13.7% attrition rate), 275 (26.5%) developed MALE during a mean follow-up of 18.9 ± 8.0 months. Kaplan-Meier analysis demonstrated significantly higher MALE incidence in patients in the At-risk group (log-rank p < 0.001). Adjusted Cox models revealed a 45% increased MALE risk in patients in the At-risk group (HR 1.45, 95% CI 1.12-1.86, p = 0.005). RCS identified a non-linear L-shaped relationship (p = 0.006) with inflection at GNRI = 95: Below 95, each 1-unit GNRI increase reduced MALE risk by 9% (HR 0.91, 95% CI 0.88-0.95, p < 0.001), while no significant association existed above 95. Subgroup analyses confirmed consistency across subgroups (all p-interaction > 0.05).

Conclusions: GNRI exhibits a non-linear L-shaped association with MALE risk in elderly patients with PAD, demonstrating critical prognostic utility below the 95 inflection point. Routine GNRI monitoring should be prioritised for patients with GNRI < 95 to guide preventive interventions.

Relevance To Clinical Practice: GNRI should be incorporated as a routine risk assessment tool for elderly patients with PAD, with particular vigilance required for those with GNRI < 95. Prioritising nutritional screening and intervention in patients with GNRI < 95 may potentially improve clinical outcomes.

Patient Or Public Contribution: Patients contributed to this study by completing follow-up assessments.

Reporting Method: This study followed the STROBE guidelines.