CRP and respiratory tract infectious disorder: In the univariate analysis, an inability to ambulate, respiratory infection, CRP level, albumin level and CAR were significantly correlated with the 28-day mortality rate (OR = 2.917, 95% CI 1.254–6.781, p = 0.013; 2.915, 1.269–6.699, p = 0.012; 1.078, 1.036–1.123, p < 0.001; 0.353, 0.187–0.668, p = 0.001; 1.281, 1.146–1.431, and p < 0.001).