title: Deep clinical remission: an optimised target in the management of rheumatoid arthritis? Experience from an ultrasonography study.
abstract: OBJECTIVE
  Treat-to-target strategy, aiming at clinical remission, has greatly improved the prognosis of RA. However, ultrasonographic subclinical synovitis is correlated with bone erosion and disease flare. The aim of this study was to evaluate whether deeper clinical remission (DAS28(ESR)≤1.98) reflects the better control of subclinical synovitis.
  
  
  METHODS
  One hundred and twenty-six RA patients in clinical remission were enrolled in the study. Disease activity and ultrasongraphy were evaluated at baseline, and every 3 months during a 12-month follow-up. The power Doppler (PD) synovitis and synovial hypertrophy (SH) of 22 joints were recorded semi-quantitatively. The relationship between the extent of clinical remission, flare and ultrasonographic features was analysed.
  
  
  RESULTS
  In 126 RA patients, 76 achieved deep clinical remission (defined as DAS28(ESR)≤1.98) and 50 achieved mild clinical remission (defined as 1.98<DAS28(ESR)≤2.6). At baseline, PD synovitis and SH were detectable in 25 (32.9%) and 34 (44.7%) in 76 patients in deep clinical remission, which were significantly less compare with those in the mild group (32.9% vs. 72.0% and 44.7% vs. 78.0%, p<0.01 for both). In all, 54 (42.9%) patients relapsed at average of 6.8±3.3 months during follow-up. Patients in deep remission possessed not only lower risk to relapse (30.3% vs. 62.0%, p<0.01), but also longer duration of remission before relapse (8.1±3.3 vs. 5.9±3.1 months, p<0.05). Besides, applying DAS28(ESR)<1.895 to predict ultrasonographic remission defined as negativity of both PD and SH was highly accurate (p<0.001). Subclinical PD synovitis at baseline was an independent risk factor for predicting relapse in RA patients achieved clinical remission (OR 8.8 [95% CI 2.7-28.4]).
  
  
  CONCLUSIONS
  Subclinical synovitis was common in RA patients even in deep clinical remission. The deeper the clinical remission, the milder the subclinical synovitis, and the lower risk to relapse. Therefore, achieving deeper clinical remission, which reflected better control of subclinical synovitis and less tendency to flare, could be an optimised treatment target of RA.
authors.affiliation: Department of Rheumatology and Clinical Immunology, Peking University First Hospital, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Geng
authors.affiliation: Department of Rheumatology and Clinical Immunology, Peking University First Hospital, Beijing, China.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Han
authors.affiliation: Department of Rheumatology and Clinical Immunology, Peking University First Hospital, Beijing, China.
authors.forename: Xuerong
authors.initials: X
authors.lastname: Deng
authors.affiliation: Department of Rheumatology and Clinical Immunology, Peking University First Hospital, Beijing, China. zhuoli.zhang@126.com.
authors.forename: Zhuoli
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000328:Adult; D019540:Area Under Curve; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000000981:diagnostic imaging* / Q000628:therapy*; D015415:Biomarkers / Q000097:blood; D001799:Blood Sedimentation; D016009:Chi-Square Distribution; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D006801:Humans; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D012008:Recurrence; D012074:Remission Induction; D012307:Risk Factors; D012720:Severity of Illness Index; D013585:Synovitis / Q000097:blood / Q000000981:diagnostic imaging* / Q000628:therapy*; D013997:Time Factors; D016896:Treatment Outcome; D018608:Ultrasonography, Doppler
chemical_list: D015415:Biomarkers