Table 4 Clinical, laboratory and genetic comparison between patients with BMD Z-score above and below − 2 (Univariate analysis)

T950C (rs2073617)

Genotypes:

TT

TC

CC

14(73.7%)

3(15.8%)

2(10.5%)

8(19.5%)

18(43.9%)

15(36.5%)

11.5(3.2–41.6)

0.2(0.06–0.95)

0.2(0.04–1.007)

Alleles:

T allele

C allele

31(81.6%)

7(18.4%)

34(41.5%)

48(58.5%)

6.2(2.5–15.9)

T245G (rs3134069)

Genotypes:

TT

TG

GG

4(21%)

9(47.4%)

6(31.6%)

8(19.5%)

21(51.2%)

12(29.3%)

1.1(0.29–4.2)

0.86(0.29–2.5)

1.1(0.34–3.6)

Alleles:

T allele

G allele

17(44.7%)

21(55.3%)

37(45.1%)

45(54.9%)

0.97

0.96(0.45–2.1)

RANKL (ng/L)

OPG (ng/L)

RANKL/OPG

129.2 ± 101.4

5.4 ± 3.6

27.7 ± 25.7

65.7 ± 78.6

7.6 ± 5.8

10.6 ± 14.7

(15.5-111.4)

(-5.1-0.6)

(4.03–30.2)

Sex male/female N(%)

3(15.8%)/16(84.2%)

19(64.3%)/22(53.7%)

0.22(0.06–0.86)

Age at diagnosis/years

8.5 ± 3.3

7.3 ± 3.2

(-0.7- 2.9)

Duration of illness (months)

Above/below 36 months N(%)

64.4 ± 32.1

16(84.2%)/3(15.8%)

48.6 ± 34.4

20(48.8%)/21(51.2%)

8.8(-2.9- 34.5)

6.7(1.1–12.9)

BMI Z-score

1.1 ± 1.01

0.79 ± 1.34

0.2(-1–0.38)

Type of onset: n (%)

Systemic

Polyarticular

Oligoarticular

Psoriatic

Enthesitis-related arthropathy

11(52.6%)

6(31.6%)

2(15.8%)

0

0

12(29.3%)

16(39%)

9(22.1%)

2(4.8%)

2(4.8%)

2.7(0.87–8.2)

0.7(0.2–2.3)

0.7(0.16–2.8)

Steroid use yes/no, N(%)

Methotrexate use yes/no N(%)

Biological treatment yes/no, N(%)

17(89.5%)/2(10.5%) 16(84.2%)/3(15.8%) 5(26.3%)/14(73.7%)

24(58.5%)/17(41.5%)

32(78%)/9(22%)

7 (17.1%)/34(82.9%)

6.02(1.2–29.6)

1.5(0.35–6.3)

1.7(0.47–6.4)

Cumulative steroid dose (mg/kg)

75.7 ± 24.1

38.1 ± 16.1

5.6(6.9-32.25)

Number of swollen joints

3.3 ± 4.8

2.02 ± 3.5

1.3(-0.96-3.4)

Number of tender joints

4.3 ± 4.6

2.7 ± 3.7

0.9(1.6–1.2)

Number of joints with limited mobility

2.05 ± 3.3

1.2 ± 2.4

0.3(-0.72-2.3)

Rheumatoid factor + ve/-ve

N(%)

6(31.6%)/13(68.4%)

13(31.7%)/28(68.3%)

1.1(0.4–3.3)

JADAS-27

14.9 ± 13.5

15.4 ± 12.4

1.8(-7.8 -6.9)

Damage index

Articular

Extraarticular

12.8 ± 10.5

3.2 ± 2.3

5.7 ± 8.7

1.8 ± 1.7

0.8(1.9–12.2)

1.3(0.4–2.5)