Geriatric Nutritional Risk Index and overall-cause mortality prediction in institutionalised elderly: a 3-year survival analysis

Abstract

Background & aims: A new tool, the Geriatric Nutritional Risk Index (GNRI), was recently proposed to predict short-term complications in elderly medical patients but no information is available when long-term follow-up periods are considered.

Methods: A 3-year follow-up study in 245 institutionalised elderly (51 M:194 F; 83.7+/-8.6 years). Nutritional risk was graded by GNRI (severe, <82; moderate, 82 to <92; mild, 92-98; no risk, >98). Main outcome was overall-cause death.

Results: After the follow-up 99 (26 M:73 F) events occurred. Nutritional risk prevalence was 5.7%, 24.1%, 34.7% and 35.5% and mortality rates were 71.4%, 48.6% 33.7% and 34.3% with the GNRI<82, 82 to <92, 92-98, and >98, respectively. Kaplan-Meier curves were significantly associated to GNRI (p=0.0068). GNRI<82 was consistently related to death (odds ratio, OR=5.29, [95%CI: 1.43-19.57], p=0.0127) when compared to GNRI>98. Similar results were confirmed by Cox regression (hazard ratio, HR=2.76 [95%CI: 1.89-4.03], p=0.0072). Finally, when "severe" and "moderate" risk were analysed as a single class (GNRI<92) outcome associations were: OR=2.17, [95%CI: 1.10-4.28] (p=0.0245); HR=1.76 [95%CI: 1.34-2.23] (p=0.0315). Survival analysis showed higher mortality rates by GNRI<92 (p=0.0188).

Conclusions: Present data support the use of the GNRI in the evaluation of long-term nutrition-related risk of death. We suggest a GNRI<92 as clinical trigger for nutritional support in institutionalised elderly.