Table 1 Disease characteristics according to BMI groups in the 18-year follow-up visit

Female, n (%)

15(71)

173(73)

42(71)

24(63)

0.30

Age at onset, years, mean (SD)

4.0(3.2)

6.1(4.1)

7.8(3.8)

7.9(3.9)

 < 0.001

Symptom duration, months, mean (SD)

8(16)

5(8)

7(9)

5(7)

0.95

ISO-BMI at onset, (z-score) mean (SD)

-1.51(3.69)

1.08(3.24)

2.39(2.93)

3.10(2.32)

 < 0.001

JADAS at onset

2.2(3.6)

2.0(3.6)

1.9(3.3)

2.0(2.8)

0.80

Age

20.8(4.0)

22.9(4.4)

24.7(4.2)

25.2(4.3)

 < 0.001

Disease duration

16.5(2.9)

16.7(1.6)

16.6(1.4)

17.1(1.0)

0.24

Subgroup of JIA, n (%)

0.014

 Persistent oligoarthritis

9(43)

66(28)

10(17)

6(16)

 Extended oligoarthritis

3(14)

58(24)

10(17)

4(11)

 Polyarthritis, RF-positive

1(5)

2(1)

1(2)

2(5)

 Polyarthritis, RF-negative

5(24)

42(18)

10(17)

4(11)

 Psoriatic arthritis

1(5)

7(3)

4(7)

6(16)

 Enthesitis-related

0(0)

21(9)

8(14)

6(16)

 Systemic onset

0(0)

11(5)

2(3)

0(0)

 Undifferentiated

2(10)

30(13)

14(24)

10(26)

DAS28

1.92(0.97)

1.83(0.86)

1.91(0.97)

2.26(1.01)

0.028

 Tender joints 28

1.3(2.0)

0.6(1.7)

0.9(2.1)

1.9(4.3)

0.019

 Swollen joints 28

0.5(0.7)

0.3(1.1)

0.5(1.5)

0.3(1.2)

0.92

 Patients’ global, VAS

20.5(24.5)

14.7(22.7)

26.2(29.9)

29.3(33.8)

 < 0.001

 ESR

5.5(4.8)

6.7(6.8)

7.6(6.7)

12.3(9.6)

 < 0.001

 CRP

3.8(2.5)

2.8(3.7)

3.7(3.9)

7.2(8.3)

 < 0.001

HAQ

0.15(0.35)

0.13(0.31)

0.33(0.59)

0.38(0.65)

 < 0.001

Remission

0.17

 No remission

14(67)

110(46)

24(41)

21(55)

 Remission on medication

0(0)

26(11)

3(5)

4(11)

 Remission off medication

7(33)

101(43)

32(54)

13(34)

Pain, VAS

26.0(27.8)

15.8(22.0)

24.5(27.7)

28.1(29.9)

0.013

Fatigue total, mean (SD)

3.0(1.6)

3.1(1.5)

3.5(1.7)

3.6(1.6)

0.035

PSQI, mean (SD)

5.4(2.7)

5.5(3.4)

6.0(4.1)

6.8(4.1)

0.044

Kasari FIT-index

29.0(20.9)

33.9(23.2)

35.5(21.8)

28.8(19.2)

0.68

Abdominal pain

 < 0.001

 No

17(81)

197(83)

42(71)

24(63)

 Sometimes

3(14)

25(11)

8(14)

3(8)

 Always

1(5)

15(6)

9(15)

11(29)

Comorbidities

 Hypothyreosis

0(0)

6(3)

2(3)

0(0)

0.78

 IBD

2(10)

7(3)

1(2)

1(3)

0.30

Social status

0.004

 Student

10(48)

119(50)

27(46)

9(24)

 Employed

6(29)

108(46)

29(49)

22(58)

 Unemployed

3(14)

5(2)

1(2)

1(3)

 On pension

2(10)

5(2)

2(3)

6(16)