A simple 5-point scoring system, NaURSE (Na+, Urea, Respiratory Rate and Shock Index in the Elderly), predicts in-hospital mortality in oldest old

Abstract

the mortality is high in acutely ill oldest old patients. Understanding the prognostic factors which influence mortality will help clinicians make appropriate management decisions. we analysed prospective mortality audit data (November 2008 to January 2009) to identify variables associated with in-patient mortality in oldest old. We selected those with P < 0.10 from univariate analysis and determined at which cut-point they served as the strongest predictor of mortality. Using these cut-off points, we constructed multivariate logistic regression models. A 5-point score was derived from cut-off points which were significantly associated with mortality tested in a smaller independent re-audit sample conducted in October 2011. a total of 405 patients (mean 93.5 ± 2.7 years) were included in the study. The mean length of stay was 18.5 ± 42.4 days and 13.8% died as in-patients. Variables (cut-off values) found to be significantly associated with in-patient mortality were admission sodium (>145 mmol/l), urea (≥14 mmol/l), respiratory rate (>20/min) and shock index (>1.0): creating a 5-point score (NaURSE: NaURS in the Elderly). The crude mortality rates were 9.5, 19.9, 34.4, 66.7, and 100% for scores 0, 1, 2, 3 and 4, respectively. Using the cut-off point of ≥2, the NaURSE score has a specificity of 87% (83.1-90.3) and sensitivity of 39% (28.5-50.0), with an AUC value of 0.69 (0.63-0.76). An external independent validation study (n = 121) showed similar results. the NaURSE score may be particularly useful in identifying oldest old who are likely to die in that admission to guide appropriate care.