Long-term Outcomes of Patients with Rheumatoid Arthritis in Remission

Disease activity remission status

Remission status will be assessed according to e.g the disease activity score DAS, the Simplified Disease Activity Index (SDAI) and ACR/EULAR Boolean 2.0 remission. DAS includes the ritchie articular index, the swollen joint count (based on 44 joints), the ESR and the Patient's Global Assessment of disease activity on a VAS 0-100 mm (PGA). The following cut-points are used: High disease activity: DAS \> 3.7; Moderate disease activity: 3.7 ≥ DAS\>2.4; Low disease activity: 2.4 ≥ DAS ≥ 1.6; In remission: DAS \< 1.6 The SDAI includes tender and swollen joints (of 28), PGA, PhGA and CRP. According to SDAI, the following cut-points are used: High disease activity: SDAI\> 26.0; Moderate disease activity: 26.0 ≥ SDAI\>11.0; Low disease activity: 11.0 ≥ SDAI \> 3.3; In remission: SDAI ≤ 3.3 ACR/EULAR 2.0 remission is defined as the combination of tender joints ≤ 1, swollen joints ≤ 1, CRP ≤ 1 and patient global assessment ≤ 2 (on a scale 0-10).

Disease Modifying Anti-Rheumatic Drug (DMARD)-free remission

The prevalence of DMARD-free remission

Radiographic score (van der Heijde modified Sharp score (vdHSS)

Radiographs of hands and feet. The van der Heijde-modified Sharp scoring method will be used, which assesses erosions in 16 joints of each hand (range, 0-5 for each joint) and in 6 joints of each foot (range, 0-10 per joint) and joint space narrowing in 15 joints for each hand and in 6 joints for each foot (range, 0-4 per joint).This gives scores for erosions on a scale from 0 to 280 and joint space narrowing on a scale from 0 to168, thus the total van der Heijde-modified Sharp score ranges from 0 to 448, with higher scores indicating greater joint damage.

Radiographic joint damage progression

Radiographs of hands and feet. The van der Heijde-modified Sharp scoring method will be used, which assesses erosions in 16 joints of each hand (range, 0-5 for each joint) and in 6 joints of each foot (range, 0-10 per joint) and joint space narrowing in 15 joints for each hand and in 6 joints for each foot (range, 0-4 per joint).This gives scores for erosions on a scale from 0 to 280 and joint space narrowing on a scale from 0 to168, thus the total van der Heijde-modified Sharp score ranges from 0 to 448, with higher scores indicating greater joint damage. The images will be compared to the last corresponding images undertaken in the ARCTIC REWIND trial. Progression will be calculated as e.g. annual increase in van der Heijde modified Sharp score ≥ 1 unit.

Health-related quality of life

EuroQol-5 Dimensions three-level (EQ-5D-3L) is a utility instrument for measurement of health-related quality of life. It comprises the following five dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. Each dimension has 3 levels: no problems, some problems, and extreme problems (labelled 1-3). They have no arithmetic properties and should not be used to derive a summary score. To derive the summary index score an appropriate value set is required, which provides values (weights) for each health state description according to the preferences of the general population of a country/region

Patient global assessment of disease activity

0-100 visual analogue scale (VAS), with higher scores Indicating more disease activity

Physician global assessment of disease activity

0-100 visual analogue scale (VAS), with higher scores Indicating more disease activity

Ultrasound inflammation

Ultrasound joint inflammation will be assessed by use of a validated 0-3 semi-quantitative scoring system for power Doppler and grey scale with an ultrasound atlas as reference. In the total ultrasound score 32 joints will be included: Bilateral metacarpophalangeal (MCP) joint I-V, radiocarpal joint, distal radioulnar joint, intercarpal joint, elbow, knee, talocrural joint and metatarsophalangeal (MTP) joint I-V, yielding a maximum total score of 96. In addition to the 32 joints the following will be scored: Bilateral proximal Interphalangeal (PIP) 2 and 3 joints, extensor carpi ulnaris tendon and tibialis posterior tendon.