Observe the Frequency of Extra-Axial Symptoms in Korean Ankylosing Spondylitis (AS) Patients

The baseline assessment was performed prior to the first dose of adalimumab. The presence of peripheral arthritis (arthritis affecting shoulders, elbows, wrists, hands, knees, ankles, feet), enthesitis (inflammation of the areas where ligaments or tendons insert into bone) and dactylitis (inflammation of finger and/or toe joints) was noted. Peripheral arthritis was defined as ≥1 swollen joint on the Swollen Joint Count scale (SJC; range, 0 to 44, excluding hip joints). Enthesitis was defined as at least one inflamed enthesis in the Maastricht Ankylosing Spondylitis Enthesitis Score (MASES, 0 to 13, with higher scores representing more severe disease) or of the plantar fascia of the foot. Dactylitis was measured by a simple count of dactylitic digits.

The Bath Ankylosing Spondylitis (AS) Disease Activity Index assesses disease activity by asking the participant to answer 6 questions (each on a 10 point numeric rating scale [NRS]) pertaining to symptoms experienced for the past week. For 5 questions (level of fatigue/tiredness, level of AS neck, back or hip pain, level of pain/swelling in joints, other than neck, back or hips, level of discomfort from any areas tender to touch or pressure, and level of morning stiffness), the response is from 0 (none) to 10 (very severe); for Question 6 (duration of morning stiffness), the response is from 0 (0 hours) to 10 (≥ 2 hours). The overall BASDAI score ranges from 0 to 10. Lower scores indicate less disease activity. BASDAI 50 is a 50% improvement from baseline in BASDAI score.

Assessment of enthesitis was performed in the following 7 domains: 1) 1st costochondral joint left and right, 2) 7th costochondral joint left and right, 3) posterior superior iliac spine left and right, 4) anterior superior iliac spine left and right, 5) iliac crest left and right, 6) 5th lumbar spinous process and 7) proximal insertion of Achilles tendon left and right. Each domain was graded for the presence (1) or absence (0) of tenderness yielding total MASES ranging from 0 (0 sites with tenderness) to 13 (worst possible score; 13 sites with tenderness). Negative values indicate improvement from baseline.

The plantar fascia is a ligament that runs along the bottom of each foot. The percentage of participants who had enthesitis of the plantar fascia was documented at each study visit.

Assessment of the presence or absence of dactylitis (inflammation of finger and/or toe joints) as well as grading of tenderness and swelling in all 20 of the participants' digits was performed. Tenderness at each site was quantified from absent to severe. Swelling was quantified from mild to severe. Total Dactylitis Assessment scores ranged from 0 (no digits with dactylitis) to 20 (worst possible score; 20 digits with dactylitis). Negative values indicate improvement from baseline.

Forty-six joints were assessed for tenderness by physical examination. Tenderness of each joint was classified as present (1) or absent (0), for a total possible TJC score of 0 (0 joints with tenderness) to 46 (worst possible score/46 joints with tenderness). Negative values indicate improvement from baseline.

Forty-four joints, excluding hip joints, were assessed for swelling by physical examination. Swelling of each joint was classified as present (1) or absent (0), for a total possible score SJC of 0 (0 joints with swelling) to 44 (worst possible score/44 joints with swelling). Negative values indicate improvement from baseline.