Table 1 Clinical and demographic data of the sample, comparing HLA-B27 positive with HLA-B27 negative patients

Cases

21 (24.7)

64 (75.3)

1.27 (0.62–2.60)

0.514^**

Controls

20 (29.4)

48 (70.6)

-

Mean age (SD)

43.9 (11.6)

44.0 (10.9)

0.01 (-0.36-0.34)^ξ

0.95

Sex

Male

15 (16.3)

77 (83.7)

3.81 (1.8–8.07)

0.001^*

Female

26 (42.6)

35 (57.4)

Disease duration (years)

8.9 (7.2)

11.7 (10.7)

0.068^#

Comorbidities

Cardiopathy

0 (0)

5 (100)

0.73 (0.64–0.84)

0.33^**

Diabetes

2 (22.2)

7 (77.8)

1.16 (0.22–6.10)

1.0^**

Lung disease

0 (0)

2 (100)

0.74 (0.65–0.84)

1.0^**

Kidney disease

0 (0)

1 (100)

0.75 (0.66–0.84)

1.0^**

Hypertension

7 (25.9)

20 (74.1)

0.90 (0.31–2.59)

0.86^*

Obesity (BMI > 30 kg/ m²)

2 (20)

8 (80)

1.35 (0.26–6.95)

1.0^**

No comorbidities

8 (24.2)

25 (75.8)

1.04 (0.37–2.87)

0.94^*

Current lifestyle habits

Active smoking

1 (16.7)

5 (83.3)

1.69 (0.18–15.3)

1.0^**

Alcohol intake

1 (16.7)

5 (83.3)

1.69 (0.18–15.3)

1.0^**

Medications

IL17 inhibitors

5 (35.7)

9 (64.9)

0.62 (0.19-2.0)

0.43^*

TNF inhibitors

30 (27.3)

80 (72.7)

0.91 (0.41–2.04)

0.83^**

Current corticosteroids (yes or no))

3 (42.9)

4 (57.1)

0.46 (0.10–2.19)

0.39^**

Oral CE < 10 mg/day

2 (33.3)

4 (66.6)

0.33 (0.10–1.03)^ξ

0.429

Methotrexate

2 (18.2)

9 (81.8)

1.55 (0.30–7.84)

0.72^**

Sulfasalazine

5 (25.0)

15 (75.0)

1.11 (0.37–3.28)

0.85^*

Disease activity

VAS

4.1 (2.7)

2.6 (2.6)

0.72 (0.30–1.13)**

0.007^#

BASDAI

4.2 (2.2)

2.5 (2.4)

0.34 (-0,18-0.87)**

0.01^#

ASDAS-ESR

5.7 (13.8)

2.8 (3.6)

-0.06 (-0.55-0.43)**

0.20^#

ASDAS-CRP

3.2 (2.4)

3.8 (11.6)

0.08^#