High-sensitivity C-reactive protein/albumin ratio as a predictor of in-hospital mortality in older adults admitted to the emergency department

OBJECTIVE The objective of this study was to test the hypothesis that an elevated high-sensitivity C-reactive protein (hs-CRP)/albumin ratio at admission increases the risk of mortality in older patients admitted to the hospital via the emergency department (ED). METHODS We performed a retrospective analysis of patients admitted to the ED with any medical problem between May 2013 and October 2013 who were older than 65 years. The hs-CRP and albumin levels were measured at the time of admission to the ED. The primary outcome was all-cause in-hospital mortality. Multivariate logistic analysis was performed. RESULTS A total of 811 patients were finally included in this study. The mean age was 76±7 years, and 438 subjects (54%) were male. The in-hospital mortality rate was 9.0% (73 patients). The hs-CRP/albumin ratio was higher in nonsurvivors than in survivors (34.2±37.6 vs. 16.2±25.5, P<0.001). Multivariate logistic analysis showed that the hs-CRP/albumin ratio was associated with all-cause in-hospital mortality after adjusting for other confounding factors (odds ratio, 1.011; 95% confidence interval [CI], 1.003 to 1.020). The prognostic value of the hs-CRP/albumin ratio for predicting mortality (area under the curve, 0.728; 95% CI, 0.696 to 0.758) was greater than that of hs-CRP alone (area under the curve, 0.706; 95% CI, 0.674 to 0.738; P<0.001). CONCLUSION The hs-CRP/albumin ratio at admission to the ED is associated with all-cause in-hospital mortality among patients older than 65 years. The hs-CRP/albumin ratio may serve as a surrogate marker of disease severity.