Synovitis and Osteitis Is Very Frequent in Rheumatoid Arthritis (RA) Patients in Clinical Remission: Results from a MRI Study of 300 RA Patients in Clinical Remission or Low Disease Activity State

[141] - Synovitis and Osteitis Is Very Frequent in Rheumatoid Arthritis (RA) Patients in Clinical Remission: Results from a MRI Study of 300 RA Patients in Clinical Remission or Low Disease Activity State.

Frederique Gandjbakhch¹,Philip G Conaghan²,Bo Ejbjerg³,Espen Haavardsholm⁴,Violaine Foltz⁵,Andrew Brown²,Uffe Moller Dohn⁶,Marissa Lassere⁷,Jane Freeston²,Pernille Bøyesen⁴,Paul Bird⁸,Bruno Fautrel⁵,Merete Lund Hetland³,Paul Emery, MA, MD, FRCP⁹,Pierre Bourgeois⁵,Kim Hørslev-Petersen¹⁰,Tore Kvien⁴,Fiona M McQueen, MD¹¹,Mikkel Østergaard, MD, PhD, DMSc¹². ¹Hôpital Pitié-Salpétrière, Université PARIS VI - UPMC, Paris, France, Paris,²University of Leeds, Leeds, UK,³Copenhagen University Hospitals at Hvidovre and Glostrup, Denmark,⁴Diakonhjemmet Hospital, University of Oslo, Norway,⁵Hôpital Pitié-Salpétrière, Université PARIS VI - UPMC, Paris, France,⁶University Hospitals at Hvidovre and Glostrup, Denmark,⁷St. George Hospital, University of NSW, Sydney, Australia,⁸Division of medicine, university of NSW, Sydney Australia,⁹Academic Unit of Musculoskelet, Chapel Allerton Hospital, Leeds,¹⁰King Christian X’s Hospital for Rheumatic Diseases, University of Southern Denmark,¹¹Molecular Medicine, Univ of Auckland Sch of Med, Auckland,¹²Dept of Rheumatology 232, Hvidovre University Hosp, Hvidovre

Background: The OMERACT rheumatoid arthritis magnetic resonance imaging score (RAMRIS) has been validated for RA monitoring and has been demonstrated to be reliable, sensitive to change and discriminative. Structural progression may occur despite clinical remission. However, remission and low disease activity (LDA) are defined on clinical criteria, and MRI may reveal subclinical inflammation.
Objective: To determine MRI characteristics of RA patients in clinical remission or LDA state.
Materials and Methods: Databases issued from 6 different cohorts were collected from 5 centres. RA patients in clinical remission or LDA state (defined as DAS28-CRP < 3.2) with available MRI data were included. MRIs were assessed according to RAMRIS. Data were analysed using SAS software, version 9.1.
Results: 300 patients in clinical remission (219 patients) or LDA state (81 patients) were included. Patient characteristics: 69% female, age: median 55(IQR 43-63) years, disease duration 2.4(0.7-5.1) years, DAS28-CRP 2.2(1.7-2.6), SDAI: 3.9(1.9-6.5), CDAI: 3.1(1.5- 5.8), RF/anti-CCP positivity: 56%/54%, presence of radiographic erosions: 67 %. Wrist and MCP-MRI data were available for 287 patients and 247 patients respectively. MRI inflammatory activity was observed in the majority of patients, as synovitis and bone edema (osteitis) were observed in wrist or MCP joints in 95 % and 35% of the patients, respectively (figure1). The median (IQR) RAMRIS score for synovitis was 6(3-9) and for osteitis was 0(0-2).
The occurrence of synovitis and bone edema was not significantly different between patients in DAS28-clinical remission (synovitis/osteitis 96%/35%) and patients in LDA but not remission (synovitis/osteitis 91%/36%)(p=0.15/0.87). A trend towards lower frequencies of synovitis and osteitis in patients fulfilling more stringent remission criteria (SDAI and CDAI) was observed (data not shown).
Conclusion: Subclinical inflammation was revealed by MRI in the majority of RA patients in clinical remission or LDA state. This may explain structural progression in such patients. It should be considered whether future remission criteria should include modern imaging.

Keywords: rheumatoid arthritis (RA), magnetic resonance imaging (MRI), remission

Disclosure:

• Frederique Gandjbakhch:
  Nothing to disclose.
• Philip G Conaghan:
  Nothing to disclose.
• Bo Ejbjerg:
  Nothing to disclose.
• Espen Haavardsholm:
  Nothing to disclose.
• Violaine Foltz:
  Nothing to disclose.
• Andrew Brown:
  Nothing to disclose.
• Uffe Moller Dohn:
  Nothing to disclose.
• Marissa Lassere:
  Nothing to disclose.
• Jane Freeston:
  Nothing to disclose.
• Pernille Bøyesen:
  Nothing to disclose.
• Paul Bird:
  Abbott Laboratories: Consulting fees
  Roche: Consulting fees
  Wyeth Pharmaceuticals: Consulting fees
• Bruno Fautrel:
  Nothing to disclose.
• Merete Lund Hetland:
  Nothing to disclose.
• Paul Emery:
  Nothing to disclose.
• Pierre Bourgeois:
  Nothing to disclose.
• Kim Hørslev-Petersen:
  Nothing to disclose.
• Tore Kvien:
  Nothing to disclose.
• Fiona McQueen:
  Nothing to disclose.
• Mikkel Østergaard:
  Nothing to disclose.