Table 1 Subject characteristics and concentration of MCH

Age (years)

66.50 ± 2.93

65.07 ± 4.37

0.147

Height (cm)

159.40 ± 4.12

160.7 ± 4.51

0.264

Body weight (kg)

57.40 ± 5.37

59.61 ± 4.37

0.093

BMI (kg/m²)

22.55 ± 1.39

23.06 ± 0.85

0.099

ASA

I~II

I~II

Education years (years)

5.93 ± 1.36

6.04 ± 1.11

0.756

MCH (pg/ml)

37.17 ± 3.66

21.52 ± 3.82

< 0.0001