The significant differences in previous SAH (P = 0.0108), hypertension (P = 0.0227), reperfusion therapy (P < 0.0001), lipid-lowering drug therapy (P = 0.0359), antiplatelet therapy (P < 0.0001), hospital stay (P < 0.0001), and CRP (P = 0.0053) between the mortality and survivor groups were mainly observed in patients with pneumonia. Here, CRP is linked to pneumonia.