TTR and susceptibility to pneumonia measurement: The correlation between postoperative pneumonia and sarcopenia was coordinated in subgroups as below: age (≤65 years versus >65 years; P = 0.852 for interaction), gender (male versus female; P = 0.485 for interaction), prealbumin (≥160 mg/L versus <160 mg/L; P=0.921 for the interaction) and BMI (underweight versus normal weight/overweight; P = 0.785 for interaction), as shown in Figure 1.