title: What causes a small increase in radiographic progression in rheumatoid arthritis patients tapering TNF inhibitors?
abstract: OBJECTIVE
  In a randomised controlled trial investigating tapering of TNF inhibitors (TNFi) compared with usual care (UC) in rheumatoid arthritis patients, minimal radiographic progression was more frequent in patients who attempted tapering. Possible explanations include higher incidence of flaring, higher mean disease activity or lower TNFi use.
  
  
  METHODS
  18 months data from the DRESS study were used. Change in Sharp-van der Heijde (ΔSvdH) score (linear regression) and proportion of patients with >0.5 ΔSvdH (logistic regression) were used as outcomes. The cumulative incidence and number of short-lived and major flares per patient, mean time-weighted disease activity (MTW-DAS28-CRP) and TNFi use were used as independent variables. Regression models were performed stratified per study group and corrected for possible confounders.
  
  
  RESULTS
  175 of 180 patients had 18-month data available. The mean ΔSvdH were 0.75 and 0.15 units with 37 of 116 (32%) and 9 of 59 (15%) patients exceeding 0.5 points in the tapering and UC group, respectively (both p<0.05). MTW-DAS28-CRP, but not incidence or number of short-lived or major flares, or TNFi use, was independently associated with the mean progression score, but only in the tapering group. Additional analyses on DAS28-CRP subcomponents showed that this was mainly caused by MTW swollen joint count. No confounders were identified.
  
  
  CONCLUSIONS
  Radiographic progression was associated with higher MTW-DAS28-CRP (and especially swollen joint count), but only in patients who tapered TNFi. This finding stresses the importance of maintaining disease activity as low as possible in patients in whom TNFi is tapered and to check for radiographic progression regularly.
  
  
  BACKGROUND
  NTR 3216; Post-results.
authors.affiliation: Department of Rheumatology , Sint Maartenskliniek Nijmegen , The Netherlands.
authors.forename: Chantal A M
authors.initials: CA
authors.lastname: Bouman
authors.affiliation: Department of Rheumatology, Sint Maartenskliniek Nijmegen, The Netherlands; Department of Rheumatology, Radboud University Medical Center, The Netherlands.
authors.forename: Alfons A
authors.initials: AA
authors.lastname: den Broeder
authors.affiliation: Department of Rheumatology , Sint Maartenskliniek Nijmegen , The Netherlands.
authors.forename: Aatke
authors.initials: A
authors.lastname: van der Maas
authors.affiliation: Department of Rheumatology, Sint Maartenskliniek Nijmegen, The Netherlands; Department of Rheumatology, Radboud University Medical Center, The Netherlands.
authors.forename: Frank H J
authors.initials: FH
authors.lastname: van den Hoogen
authors.affiliation: Department of Rheumatology , Academic Medical Center , Amsterdam , The Netherlands.
authors.forename: Robert B M
authors.initials: RB
authors.lastname: Landewé
authors.affiliation: Department of Rheumatology , Sint Maartenskliniek Nijmegen , The Netherlands.
authors.forename: Noortje
authors.initials: N
authors.lastname: van Herwaarden
keywords: Anti-TNF; DMARDs (biologic); Disease Activity; Rheumatoid Arthritis; Treatment