Table 4 Binary logistic regression with preoperative predictors of delirium (Nagelkerke's R² of 39.6%)

0.005

< 70 years

13.0

Reference

≥ 70 years

40.5

4.30

1.54-12.04

0.018

> 27

12.2

Reference

24-27

27.4

2.23

0.76-6.52

≤ 23

61.3

6.50

1.75-24.13

0.934

0 to 3

12.1

Reference

4 to 6

27.2

0.74

0.19-2.83

7 to 9

37.1

0.98

0.24-3.95

10 to 20

40.0

0.77

0.17-3.46

0.001

No

22.0

Reference

Yes

55.2

6.22

2.02-19.16

0.513

> 120 g/L

20.4

Reference

≤ 120 g/L

47.9

0.72

0.27-1.93

0.447

< 1,000 pg/mL

17.4

Reference

≥ 1,000 pg/mL

41.0

1.43

0.57-3.58

0.027

> 59.5%

19.7

Reference

≤ 59.5%

58.3

3.27

1.14-9.37