GERIATRIC NUTRITIONAL RISK INDEX: A POSSIBLE INDICATOR OF SHORT‐TERM MORTALITY IN ACUTELY HOSPITALIZED OLDER PEOPLE

Abstract

To the Editor: Malnutrition is a common problem in hospitalized elderly patients1 and tends to worsen during hospitalization.2 Many methods for assessing nutritional status have emerged over the years. Early screening allows subjects at risk to be identified and nutritional complications to be prevented when prompt and adequate nutritional treatment is provided. The new Geriatric Nutritional Risk Index (GNRI) has been recently introduced for predicting nutrition-related risk of morbidity and mortality in elderly patients, whose normal weight is frequently difficult to establish.3 This has been obtained by replacing usual body weight in Buzby's Nutritional Risk Index (NRI) formula with ideal weight (NRI = (1.519 × albumin, g/L) + (41.7 × present/usual body weight); GNRI = (1.489 × albumin, g/L)+(41.7 × weight/ideal body weight)) calculated according to the Lorentz formula.3, 4 This prognostic nutritional index was designed and then validated on the basis of a 6-month severity score, which grades subject outcome (death, presence of pressure ulcers or infectious complications, alive without complications), in two series of patients (first, N=181; second, N=2,474) aged 65 and older admitted to a geriatric rehabilitation care hospital.3 Thus, the GNRI seems to fit a subacute care setting best and to address long-term complications. In elderly patients, acute life-threatening complications are more frequent, and hospital admission may be necessary to treat them. It is against this background that the utility of prognostic indexes for acute hospitalized subjects should be taken into account. Systematic recording of assessment tools at admission should allow not only for the prevention of further complications but also to indicate that the patient is in a critical state. The GNRI was used to warn of short-term (1 month) risk of death in a group of acutely hospitalized older people (73 men and 80 women; mean age±standard deviation 77.5±7.3, range 65–96; mean body mass index 26.7±5.0 kg/m2, range 14.2–37.9 kg/m2). The GNRI3 and the Mini Nutritional Assessment (MNA)5 were performed within 48 hours. Patients with hepatic or renal disease and those who were dehydrated (natremia >145 mmol/L) were excluded. According to GNRI cutoffs, 28 subjects (18.3%) were at severe risk (GNRI<82), 21 (13.7%) at moderate risk (82≥GNRI <87), 27 (17.7%) at low risk (87≥GNRI <92), and 77 (50.3%) at no risk (GNRI≥92). After 1 month, seven subjects (4.6%) had died (mean length of stay 15.0±8.1 days, range 4–25 days). All of them had a GNRI less than 82 (74.6±5.9) and a concordant MNA score less than 17 (malnutrition; 12.3±3.8). Accordingly, 25% of the patients, classified as at severe risk, died. Variable indices, such as weight loss, total lymphocyte count, and albuminemia, have been suggested as good outcome predictors (morbidity and mortality).6, 7 Albumin, despite frequent use, remains an unreliable indicator of nutritional status, because it may be more related to hydration or inflammation.3, 7 Thus, adding information on ideal weight, as with the GNRI, might give a better prediction of nutrition-related complications. The good concordance found with the MNA score in this series of patients seems to further support this. The European Society of Parenteral and Enteral Nutrition recommends the MNA as the criterion standard in the identification of malnutrition in elderly patients.8 Alternatively, it should be considered that, in spite of being rapid (up to 20 min) and economical, it is sometimes difficult to get all its questions answered. In our study, this was possible also through the assistance of surrogates (e.g., family, nurses, home-care staff). Performing the GNRI takes only a few minutes (for weight and knee-height measurements and blood sample collection) and requires low-grade participation of the patients. Thus, the GNRI seems to be applicable also to acutely admitted older, giving a warning on short-term risk of mortality. The size of the sample is an obvious limit to the present observation, and future studies should be performed. Alternatively, the use of simple and accurate assessing tools in clinical practice is once again underscored. Financial Disclosure: All the authors certify that there are no affiliations with or involvement in any organization or entity with a direct financial interest in the subject matter or materials discussed in the manuscript. Author Contributions: All authors contributed to every aspect of this manuscript. Sponsor's Role: There were no sponsors for this manuscript.