Table 1 Characteristics of patients receiving elective orthopedic surgery

Demographics

 Age, years

   < 65

199,061

(44.4)

17,168

(58.8)

0.291

  65–74

153,895

(34.3)

8079

(27.7)

0.144

  75–84

79,165

(17.7)

3149

(10.8)

0.198

   ≥ 85

16,206

(3.6)

801

(2.7)

0.050

 Sex

  Female

261,338

(58.3)

13,907

(47.6)

0.215

  Male

186,989

(41.7)

15,290

(52.4)

0.215

 Functional status

  Independent

438,018

(97.7)

28,301

(96.9)

0.048

  Dependent

10,309

(2.3)

896

(3.1)

0.048

  Obesity

246,832

(55.1)

16,485

(56.5)

0.028

  Smoking

52,164

(11.6)

5143

(17.6)

0.170

Comorbidities

  Steroid use

20,427

(4.6)

1394

(4.8)

0.010

  Ascites

94

(0.0)

60

(0.2)

0.055

  Ventilator dependent

57

(0.0)

32

(0.1)

0.039

  Disseminated cancer

2250

(0.5)

390

(1.3)

0.087

  Diabetes mellitus

77,525

(17.3)

6174

(21.2)

0.098

  Hypertension

276,933

(61.8)

18,279

(62.6)

0.017

  Congestive heart failure

2180

(0.5)

221

(0.8)

0.034

  COPD

19,466

(4.3)

1511

(5.2)

0.039

  Dialysis

1652

(0.4)

123

(0.4)

0.008

  Sepsis

3089

(0.7)

529

(1.8)

0.101

Operative information

 Type of surgery

  Limb amputation

1949

(0.4)

237

(0.8)

0.048

  Spinal fusion

30,873

(6.9)

2301

(7.9)

0.038

  Open reduction of fracture

22,238

(5.0)

3504

(12.0)

0.255

  Hip prosthesis

140,844

(31.4)

8810

(30.2)

0.027

  Knee prosthesis

228,504

(51.0)

12,510

(42.9)

0.163

  Laminectomy

23,919

(5.3)

1835

(6.3)

0.041

  ASA classification

  1

9872

(2.2)

542

(1.9)

0.025

  2

211,380

(47.2)

11,801

(40.4)

0.136

  3

216,359

(48.3)

15,699

(53.8)

0.110

  4 or 5

10,716

(2.4)

1155

(4.0)

0.089