title: Association between rheumatoid arthritis disease activity, progression of functional limitation and long-term risk of orthopaedic surgery: combined analysis of two prospective cohorts supports EULAR treat to target DAS thresholds.
abstract: OBJECTIVE
  To examine the association between disease activity in early rheumatoid arthritis (RA), functional limitation and long-term orthopaedic episodes.
  
  
  METHODS
  Health Assessment Questionnaire (HAQ) disability scores were collected from two longitudinal early RA inception cohorts in routine care; Early Rheumatoid Arthritis Study and Early Rheumatoid Arthritis Network from 1986 to 2012. The incidence of major and intermediate orthopaedic surgical episodes over 25 years was collected from national data sets. Disease activity was categorised by mean disease activity score (DAS28) annually between years 1 and 5; remission (RDAS≤2.6), low (LDAS>2.6-3.2), low-moderate (LMDAS≥3.2-4.19), high-moderate (HMDAS 4.2-5.1) and high (HDAS>5.1).
  
  
  RESULTS
  Data from 2045 patients were analysed. Patients in RDAS showed no HAQ progression over 5 years, whereas there was a significant relationship between rising DAS28 category and HAQ at 1 year, and the rate of HAQ progression between years 1 and 5. During 27 986 person-years follow-up, 392 intermediate and 591 major surgeries were observed. Compared with the RDAS category, there was a significantly increased cumulative incidence of intermediate surgery in HDAS (OR 2.59 CI 1.49 to 4.52) and HMDAS (OR 1.8 CI 1.05 to 3.11) categories, and for major surgery in HDAS (OR 2.48 CI 1.5 to 4.11), HMDAS (OR 2.16 CI 1.32 to 3.52) and LMDAS (OR 2.07 CI 1.28 to 3.33) categories. There was no significant difference in HAQ progression or orthopaedic episodes between RDAS and LDAS categories.
  
  
  CONCLUSIONS
  There is an association between disease activity and both poor function and long-term orthopaedic episodes. This illustrates the far from benign consequences of persistent moderate disease activity, and supports European League Against Rheumatism treat to target recommendations to secure low disease activity or remission in all patients.
authors.affiliation: Department of Rheumatology, Whittington Hospital NHS Trust, London, UK.|Early Rheumatoid Arthritis Study, Department of Rheumatology, St Albans City Hospital, St Albans, UK.
authors.forename: Elena
authors.initials: E
authors.lastname: Nikiphorou
authors.affiliation: Psychology Department, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.|Division of Health & Social Care Research, Faculty of Life and Medical Science, King's College London, London, UK.
authors.forename: Sam
authors.initials: S
authors.lastname: Norton
authors.affiliation: Early Rheumatoid Arthritis Study, Department of Rheumatology, St Albans City Hospital, St Albans, UK.
authors.forename: Adam
authors.initials: A
authors.lastname: Young
authors.affiliation: Centre for Lifespan & Chronic Illness Research, University of Hertfordshire, Hatfield, UK.
authors.forename: Lewis
authors.initials: L
authors.lastname: Carpenter
authors.affiliation: Department of Rheumatology, New Cross Hospital, Wolverhampton, UK.
authors.forename: Josh
authors.initials: J
authors.lastname: Dixey
authors.affiliation: Arthritis UK Pain Centre, University of Nottingham, Nottingham, UK.
authors.forename: David Andrew
authors.initials: DA
authors.lastname: Walsh
authors.affiliation: Department of Rheumatology, St Georges University Hospitals NHS Foundation Trust, London, UK.
authors.forename: Patrick
authors.initials: P
authors.lastname: Kiely
mesh_terms: D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000473:pathology / Q000503:physiopathology*; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000706:statistics & numerical data*; D011446:Prospective Studies; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors
keywords: DMARDs (biologic); DMARDs (synthetic); Disease Activity; Rheumatoid Arthritis; Treatment