Table 3 Univariate and multivariable logistic regression results with VAS day as outcome

SAS

1.581 (1.420, 1.761)

<.0001

1.335 (1.149, 1.551)

0.0002

SDS

1.487 (1.353, 1.634)

<.0001

1.214 (1.070, 1.377)

0.0026

  <  1 year (reference)

1

NA

1

NA

 1–5 years

1.863 (0.921, 3.765)

0.0833

1.053 (0.367, 3.020)

0.924

  > 5 years

6.333 (3.272, 12.259)

<.0001

2.48 (0.900, 6.828)

0.0789

BMI

0.951 (0.888, 1.019)

0.1548

0.865 (0.766, 0.977)

0.0199

 Spinal stenosis

2.453 (1.152, 5.222)

0.02

4.252 (1.314, 13.762)

0.0157

 Spondylolisthesis

2.364 (1.077, 5.187)

0.0319

5.149 (1.514, 17.512)

0.0087

 Disc herniation (reference)

1

NA

1

NA

 Preoperative pain score (VAS)

2.574 (1.774, 3.734)

<.0001

Age

1.019 (0.994, 1.046)

0.1379

Gender (male)

0.860 (0.526, 1.405)

0.5465

Duration of surgery

1.019 (0.995, 1.045)

0.1274

Smoking

1.166 (0.709, 1.918)

0.5449

Frail

1.063 (0.768, 1.471)

0.7134

Operation history

1.025 (0.752, 1.398)

0.8762