Table 2 Predictors of sustained low BASFI (< 3) between 12 and 18 months

Age, years

0.96 (0.95, 0.98)

 < 0.001

-

-

-

-

Disease duration, years

1.0 (0.98, 1.01)

0.335

-

-

-

-

Gender, male vs female

1.3 (1.0, 1.9)

0.087

-

-

-

-

Smoking

0.8 (0.5, 1.2)

0.230

-

-

-

-

Enrollment period

0.411

-

-

-

-

 2006–2008 vs. 2016–2017

0.7 (0.4, 1.2)

 2009–2012 vs. 2016–2017

0.8 (0.4, 1.4)

 2013–2015 vs. 2016–2017

1.0 (0.6, 1.6)

Biologic naïve

1.0 (0.6, 1.6)

0.956

-

-

-

-

Baseline nbDMARD use

0.9 (0.6, 1.3)

0.530

-

-

-

-

Baseline NSAID use

1.1 (0.8, 1.6)

0.592

-

-

-

-

Baseline steroid use

1.2 (0.6, 2.3)

0.606

-

-

-

-

Anti-TNF, golimumab vs. infliximab

1.6 (1.1, 2.2)

0.007

-

-

-

-

Baseline enthesitis

0.9 (0.5, 1.4)

0.553

-

-

-

-

Baseline dactylitis

1.0 (0.4, 2.4)

0.967

-

-

-

-

Baseline CRP, mg/L

1.0 (0.99, 1.01)

0.257

-

-

-

-

Baseline ASDAS

0.6 (0.5, 0.8)

 < 0.001

-

-

-

-

Baseline BASDAI

0.7 (0.65, 0.8)

 < 0.001

-

-

-

-

BASFI, baseline

0.66 (0.6, 0.7)

 < 0.001

0.7 (0.6, 0.8)

 < 0.001

0.7 (0.6, 0.8)

 < 0.001

Low BASDAI < 3

 M6 and M12 vs. persistent BASDAI ≥ 3

37.3 (21.4, 64.9)

 < 0.001

10.5 (4.0, 27.2)

 < 0.001

7.4 (3.1, 17.7)

 < 0.001

 M6 or M12 vs. persistent BASDAI ≥ 3

5.5 (3.3, 4.4)

 < 0.001

5.2 (2.4, 11.1)

 < 0.001

4.0 (1.8, 8.7)

0.001

ASDAS-ID (< 1.3)

 M6 and M12 vs. persistent ASDAS ≥ 1.3

25.3 (9.2, 69.8)

 < 0.001

3.7 (1.1, 13.1)

0.040

N/A

N/A

 M6 or M12 vs. persistent ASDAS ≥ 1.3

8.5 (3.8, 18.9)

 < 0.001

2.2 (0.8, 6.0)

0.144

N/A

N/A

ASDAS-LDA (< 2.1)

 M6 and M12 vs. persistent ASDAS ≥ 2.1

31.9 (14.6, 70.1)

 < 0.001

N/A

N/A

7.2 (2.7, 19.3)

 < 0.001

 M6 or M12 vs. persistent ASDAS ≥ 2.1

3.8 (2.0, 7.1)

 < 0.001

N/A

N/A

2.1 (1.0, 4.2)

0.053