Table 1.

Baseline demographic and clinical characteristics of the patients by baseline MRI evidence of SI joint and/or spine inflammation^*

	SI joint score <2		SI joint score ≥2
	Spine score <2 (n = 56)	Spine score ≥2 (n = 53)	Spine score <2 (n = 30)	Spine score ≥2 (n = 42)
Female, %	60.7	62.3	56.7	35.7
White, %	98.2	98.1	100.0	97.6
Age, years	35.3 ± 9.6 (19.0–63.0)	40.5 ± 11.8 (19.0–72.0)	35.9 ± 9.2 (21.0–59.0)	39.6 ± 11.4 (19.0–65.0)
Symptom duration, years†	7.9 ± 6.4 (0.2–24.2)	11.6 ± 10.3 (0.6–42.4)	11.0 ± 9.0 (0.8–38.2)	10.6 ± 9.4 (0.4–38.0)
Duration since diagnosis, years	3.0 ± 4.4 (0.1–18.1)	2.9 ± 4.1 (0.1–21.2)	2.4 ± 3.1 (0.1–11.3)	3.0 ± 4.2 (0.1–17.0)
Sacroiliitis on MRI, past or present, reported by the investigator, %	37.5	32.1	70.0	69.0
HLA–B27 positive, %	76.8	84.9	80.0	71.4

^*Except where indicated otherwise, values are the mean ± SD (range). MRI = magnetic resonance imaging.

^†n = 52 for sacroiliac (SI) joint score <2 and spine score <2, and n = 28 for SI joint score ≥2 and spine score <2.