Table 2 Assessment of suppression factors for postoperative delirium

Combined admin. with

suvorexant and ramelteon

Yes (n = 50)

7 (24.10%)

43 (53.1%)

0.009

0.28

0.10–0.82

0.020

No (n = 60)

22 (75.9%)

38 (46.9%)

Age

< 75 (n = 66)

14 (48.3%)

52 (64.2%)

0.136

0.54

0.19–1.57

0.260

≥ 75 (n = 44)

15 (51.7%)

29 (35.8%)

Gender

Female (n = 52)

9 (31.0%)

43 (53.1%)

0.004

0.48

0.18–1.31

0.156

Male (n = 58)

20 (69.0%)

38 (46.9%)

Operative procedure

Hepatectomy (n = 47)

12 (41.4%)

35 (43.2%)

0.864

Pancreatectomy (n = 44)

13 (10.3%)

31 (39.5%)

0.618

Others (n = 19)

4 (13.8%)

15 (29.6%)

0.658

Performance status

0 (n = 68)

13 (44.8%)

55 (67.9%)

0.030

0.44

0.17–1.19

0.106

1≤ (n = 42)

16 (55.1%)

26 (32.1%)

History of

alcohol intake

No (n = 38)

8 (27.6%)

30 (37.0%)

0.353

Yes (n = 72)

21 (72.4%)

51 (63.0%)

History of

hypertension

No (n = 54)

9 (31.0%)

45 (55.6%)

0.022

0.51

0.19–1.40

0.194

Yes (n = 56)

20 (69.0%)

36 (44.4%)

History of

mental disorder

No (n = 101)

28 (96.6%)

73 (90.1%)

0.765

Yes (n = 9)

1 (3.4%)

8 (9.9%)

Adjuvant remedy

Opioid (n = 2)

2 (6.9%)

0 (0%)

Antidopaminergic drug (n = 1)

0 (0%)

1 (1.2%)

H₂ receptor antagonist (n = 54)

15 (51.7%)

39 (48.1%)

0.741

Steroid (n = 3)

1 (3.4%)

2 (2.5%)

0.786