Table 3 Univariate logistic regression analysis for postoperative delirium

Gender

 Male

–

–

–

–

1.000

–

 Female

−0.053

0.256

0.043

0.835

0.948

(0.574, 1.566)

Age (years)

38.093

<0.001

 <70

–

–

–

–

1.000

–

 70–79

2.709

0.738

13.478

<0.001

15.007

(3.534, 63.724)

 ≥80

3.819

0.733

27.126

<0.001

45.540

(10.822,191.637)

Blood type

4.949

0.176

 A

–

–

–

–

1.000

–

 B

−0.234

0.330

0.500

0.479

0.792

(0.414, 1.513)

 AB

−1.070

0.511

4.383

0.036

0.343

(0.126, 0.934)

 O

−0.020

0.304

0.004

0.947

0.980

(0.540, 1.779)

Type of surgery

29.940

<0.001

 IFIF

–

–

–

–

1.000

–

 FHR

0.458

0.294

2.420

0.120

1.580

(0.888, 2.813)

 THA

−1.210

0.389

9.689

0.002

0.298

(0.139, 0.639)

 TKA

−1.472

0.469

9.872

0.002

0.229

(0.092, 0.575)

Anesthesia

 General anesthesia

–

–

–

–

1.000

–

 Epidural anesthesia

0.265

0.560

0.224

0.636

1.304

(0.435, 3.909)

Preoperative hospitalization (d)

32.560

<0.001

 1–3

–

–

–

–

1.000

–

 4–6

1.522

0.294

26.807

<0.001

4.580

(2.575, 8.148)

 ≥7

0.175

0.372

0.223

0.637

1.192

(0.575, 2.469)

Preoperative comorbidities

6.004

0.111

 0

–

–

–

–

1.000

–

 1

0.302

0.291

1.075

0.300

1.352

(0.764, 2.392)

 2

0.162

0.357

0.205

0.650

1.176

(0.584, 2.369)

 ≥3

1.107

0.459

5.825

0.016

3.026

(1.231, 7.436)

Preoperative albumin (g/L)

14.368

0.001

 <35

–

–

–

–

1.000

–

 35–39

0.000

0.341

0.000

1.000

1.000

(0.513, 1.950)

 ≥40

−1.061

0.379

7.838

0.005

0.346

(0.165, 0.727)

Preoperative hemoglobin (g/L)

Anemic (male, <120; female, <1 l0)

–

–

–

–

1.000

–

Normal (male, ≥120; female, ≥110)

−0.607

0.262

5.343

0.021

0.545

(0.326, 0.912)

Postoperative electrolyte disorders

 No

–

–

–

–

1.000

–

 Yes

0.663

0.263

6.354

0.012

1.941

(1.159, 3.249)

Blood loss (mL)

3.905

0.142

 <200

–

–

–

–

1.000

–

 200–399

−0.260

0.264

0.971

0.324

0.771

(0.460, 1.293)

 ≥400

−0.866

0.456

3.606

0.058

0.421

(0.172,1.028)

Operation time (min)

19.298

<0.001

 <60

–

–

–

–

1.000

–

 60–89

−0.345

0.333

1.074

0.300

0.708

(0.369, 1.360)

 ≥90

−1.666

0.417

15.963

<0.001

0.189

(0.084, 0.428)

Postoperative ICU care

 No

–

–

–

–

1.000

–

 Yes

1.005

0.256

15.443

<0.001

2.731

(1.655, 4.507)

Blood transfusion (mL)

5.618

0.060

 <600

–

–

–

–

1.000

–

 600–1199

0.666

0.281

5.618

0.018

1.947

(1.122, 3.379)

 ≥1200

0.290

0.333

0.758

0.384

1.336

(0.696, 2.564)