Table 3 The comparison of baseline clinical and PET/CT characteristics between responders and non-responders at 3-months

Clinical assessment of disease activity

ESR, mm/h

66.1 ± 25.3

48.7 ± 31.8

0.204

61.4 ± 28.7

53.1 ± 30.9

0.558

CRP, mg/dL

5.6 ± 5.2

1.8 ± 2.0

0.035*

5.2 ± 5.0

1.8 ± 2.2

0.033*

Tender or swollen joint count

17.7 ± 7.8

12.0 ± 5.2

0.081

16.6 ± 8.2

12.8 ± 5.0

0.252

VAS of pain

6.6 ± 1.2

6.0 ± 1.6

0.357

6.5 ± 1.1

6.0 ± 0.6

0.409

PGA

5.9 ± 1.1

6.4 ± 1.5

0.378

6.0 ± 1.1

6.4 ± 1.6

0.551

EGA

6.6 ± 1.3

7.1 ± 0.8

0.346

6.5 ± 1.2

7.3 ± 0.7

0.206

HAQ-DI

1.9 ± 0.7

1.4 ± 0.8

0.088

1.9 ± 0.7

1.4 ± 0.8

0.210

SF36

46.1 ± 9.5

46.8 ± 9.8

0.882

46.1 ± 9.5

46.8 ± 9.8

0.882

CDAI

33.2 ± 10.5

31.4 ± 9.5

0.709

32.1 ± 10.6

32.8 ± 9.3

0.899

SDAI

38.8 ± 14.0

33.2 ± 10.7

0.352

37.3 ± 14.2

34.6 ± 10.7

0.647

DAS28-ESR

6.4 ± 0.9

5.9 ± 0.9

0.361

6.2 ± 1.0

6.1 ± 0.9

0.900

DAS28-CRP

6.0 ± 1.3

5.1 ± 1.1

0.119

5.9 ± 1.3

5.2 ± 1.2

0.219

⁶⁸ Ga-FAPI PET/CT

PJC_FAPI

15.5 ± 8.6

6.8 ± 4.8

0.016*

14.4 ± 8.9

7.3 ± 4.9

0.059

TSU_FAPI

803.7 ± 615.6

214.9 ± 234.6

0.015*

753.6 ± 607.2

210.2 ± 250.4

0.029*

MSV_FAPI

196.0 ± 150.9

58.6 ± 63.2

0.021*

183.7 ± 148.9

58.4 ± 67.6

0.041*

SUVmax

10.1 ± 5.4

8.0 ± 3.6

0.342

10.4 ± 5.2

7.3 ± 3.1

0.155

¹⁸F-FDG PET/CT

PJC_FDG

14.2 ± 9.6

6.6 ± 4.7

0.045*

13.2 ± 9.7

7.0 ± 4.8

0.117

TSU_FDG

433.1 ± 374.8

91.2 ± 148.4

0.021*

323.0(86.0, 614.1)

26.7(4.2, 125.4)

0.032*

MSV_FDG

121.8 ± 91.7

29.3 ± 46.4

0.014*

112.0 ± 92.8

31.1 ± 49.3

0.039*

SUVmax

6.9 ± 3.2

4.8 ± 2.0

0.141

5.6(4.7, 7.5)

4.6(3.4, 5.4)

0.127