With advancing therapeutic options, achieving a state of remission has become the treatment goal in rheumatoid arthritis. Agreeing on what constitutes remission and what measures should be used to assess disease activity has remained a challenge. Multiple remission criteria have been devised and modified, all with different strengths and limitations. A consensus definition of remission will need to be achieved if we are to be able to evaluate outcomes of clinical trials and establish treatment targets for practice. Remission defined as the complete absence of disease currently may not be a realistic therapeutic goal.

Objective

The evaluation of disease activity in obese rheumatoid arthritis (RA) patients presents challenges particularly in the clinical assessment of swollen joints. This study examines the effect of obesity on the American College of Rheumatology (ACR) core set measures used in assessing RA disease activity with specific focus on the swollen joint count (SJC).

Methods

We examined a cross-sectional cohort of 323 early seropositive RA patients (symptom duration ≤15 months). Patients were biologic-naive with equal to or more than 6/44 SJC and equal to or more than 9/44 tender joint count. The ACR core set measures, components of Disease Activity Score (DAS) 44/erythrocyte sedimentation rate (ESR), DAS28/ESR4 item, Clinical Disease Activity Index (CDAI), and body mass index (BMI) were collected. Disease activity measures were compared between BMI categories. Multivariable linear regression models assessed the relationship between high BMI (≥30 kg/m) and lower-extremity (LE) SJC and SJC44 while accounting for other ACR measures.

Results

Disease Activity Score 44/ESR4 item, Health Assessment Questionnaire Disability Index, physician global, and SJC44 differed across BMI categories (p < 0.05). Of the SJC44, metacarpophalangeal joints and LE joints (knees, ankles, metatarsophalangeal joints) were associated with increased swelling in all BMI groups (P < 0.05). Obesity was significantly associated with LE SJC after adjusting for ACR core set measures.

Conclusions

There is a direct association between increased BMI and increased swelling of LE joints in RA patients. Increases in DAS44-measured disease activity are higher in obese RA patients because of increased LE swollen joints. Disease Activity Score 28 and Clinical Disease Activity Index, which emphasize upper-extremity joint assessment, are not significantly influenced by obesity.

Objective

To evaluate the effect of sustained American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) Boolean remission on residual joint inflammation assessed by magnetic resonance imaging (MRI) and to secondarily evaluate other clinical definitions of remission, within an early seropositive rheumatoid arthritis (RA) cohort.

Methods

A subcohort of 118 RA patients was enrolled from patients who completed the 2-year, double-blind randomized Treatment of Early Aggressive Rheumatoid Arthritis (TEAR) trial. Patients received a single contrast-enhanced 1.5T MRI of their most involved wrist. Two readers scored MRIs for synovitis, osteitis, tenosynovitis, and erosions. Clinical assessments were performed every 3 months during the trial and at time of MRI.

Results

The subcohort was 92% seropositive with mean age 51 years, duration 4.1 months, and Disease Activity Score in 28 joints using the erythrocyte sedimentation rate 5.8 at TEAR entry. Total MRI inflammatory scores (tenosynovitis + synovitis + osteitis) were lower among patients in clinical remission. Lower MRI scores were correlated with longer duration of Clinical Disease Activity Index (CDAI) remission (ρ = 0.22, P = 0.03). At the time of MRI, 89 patients had no wrist pain/tenderness/swelling; however, all 118 patients had MRI evidence of residual joint inflammation after 2 years. No statistically significant differences in damage or MRI inflammatory scores were observed across treatment groups.

Conclusion

This is the first detailed appraisal describing the relationship between clinical remission cut points and MRI inflammatory scores within an RA randomized controlled trial. The most stringent remission criteria (2011 ACR/EULAR and CDAI) best differentiate the total MRI inflammatory scores. These results document that 2 years of triple therapy or tumor necrosis factor plus methotrexate treatment in early RA does not eliminate MRI evidence of joint inflammation.