Table 2 Univariate and multivariate logistic regression analysis for the risk of SBM at the initial diagnosis of LCC patients

Year of diagnosis

2010–2014

Reference

–

2015–2019

0.81 (0.59–1.12)

0.208

Age

< 60

Reference

–

Reference

–

60–79

0.58 (0.43–0.8)

0.001

0.57 (0.41–0.78)

0.001

 ≥ 80

0.24 (0.13–0.47)

 < 0.001

0.23 (0.12–0.45)

 < 0.001

Sex

Male

Reference

–

Female

1.17 (0.87–1.56)

0.307

Race

White

Reference

–

Black

0.96 (0.63–1.48)

0.863

Other

0.79 (0.39–1.63)

0.525

Marital status

Married

Reference

–

Single

0.99 (0.74–1.32)

0.94

Median household income

 < $55,000

Reference

–

$55,000–$74,999

1.24 (0.9–1.71)

0.179

$75,000+

0.96 (0.62–1.48)

0.848

Primary site

Main bronchus

Reference

–

Upper lobe

1.1 (0.53–2.29)

0.795

Middle lobe

0.7 (0.22–2.26)

0.557

Lower lobe

1.15 (0.53–2.47)

0.727

Unspecific

0.96 (0.41–2.21)

0.916

Laterality

Left

Reference

–

Right

0.84 (0.63–1.13)

0.251

Bilateral

1.04 (0.29–3.71)

0.946

Grade

III

Reference

–

Reference

–

IV

0.94 (0.64–1.37)

0.731

0.95 (0.64–1.39)

0.778

Unknown

1.41 (1–1.99)

0.052

1.25 (0.88–1.79)

0.219

T stage

T1

Reference

–

Reference

–

T2

1.22 (0.72–2.06)

0.469

1.08 (0.63–1.86)

0.775

T3

1.65 (0.99–2.74)

0.053

1.37 (0.81–2.33)

0.238

T4

1.45 (0.9–2.33)

0.127

1.1 (0.67–1.82)

0.704

T0

1.05 (0.22–4.88)

0.955

0.83 (0.17–3.99)

0.814

N stage

N0

Reference

–

Reference

–

N1

1.53 (0.89–2.64)

0.127

1.4 (0.8–2.46)

0.241

N2

1.62 (1.14–2.3)

0.007

1.29 (0.89–1.88)

0.179

N3

1.51 (0.96–2.37)

0.072

1.17 (0.72–1.88)

0.527

Bone metastases

No

Reference

–

Reference

–

Yes

2.22 (1.61–3.06)

 < 0.001

1.75 (1.22–2.51)

0.002

Liver metastases

No

Reference

–

Reference

–

Yes

2.19 (1.47–3.25)

 < 0.001

1.5 (0.96–2.34)

0.075

Lung metastases

No

Reference

–

Reference

–

Yes

1.62 (1.12–2.36)

0.011

1.28 (0.84–1.93)

0.249