title: Predictors of work disability after start of anti-TNF therapy in a national cohort of Swedish patients with rheumatoid arthritis: does early anti-TNF therapy bring patients back to work?
abstract: OBJECTIVE
  To examine predictors of work ability gain and loss after anti-tumour necrosis factor (TNF) start, respectively, in working-age patients with rheumatoid arthritis (RA) with a special focus on disease duration.
  
  
  METHODS
  Patients with RA, aged 19-62 years, starting their first TNF inhibitor 2006-2009 with full work ability (0 sick leave/disability pension days during 3 months before bio-start; n=1048) or no work ability (90 days; n=753) were identified in the Swedish biologics register (Anti-Rheumatic Treatment In Sweden, ARTIS) and sick leave/disability pension days retrieved from the Social Insurance Agency. Outcome was defined as work ability gain ≥50% for patients without work ability at bio-start and work ability loss ≥50% for patients with full work ability, and survival analyses conducted. Baseline predictors including disease duration, age, sex, education level, employment, Health Assessment Questionnaire, Disease Activity Score 28 and relevant comorbidities were estimated using Cox regression.
  
  
  RESULTS
  During 3 years after anti-TNF start, the probability of regaining work ability for totally work-disabled patients was 35% for those with disease duration <5 years and 14% for disease duration ≥5 years (adjusted HR 2.1 (95% CI 1.4 to 3.2)). For patients with full work ability at bio-start, disease duration did not predict work ability loss. Baseline disability pension was also a strong predictor of work ability gain after treatment start.
  
  
  CONCLUSIONS
  A substantial proportion of work-disabled patients with RA who start anti-TNF therapy regain work ability. Those initiating treatment within 5 years of symptom onset have a more than doubled 3-year probability of regaining work ability compared with later treatment starts. This effect seems largely due to the impact of disease duration on disability pension status.
authors.affiliation: Section of Rheumatology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden.
authors.forename: T
authors.initials: T
authors.lastname: Olofsson
authors.affiliation: Clinical Epidemiology Unit, Orthopedics, Department of Clinical Sciences Lund, Lund University, Lund, Sweden.
authors.forename: I F
authors.initials: IF
authors.lastname: Petersson
authors.affiliation: Clinical Epidemiology Unit, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.
authors.forename: J K
authors.initials: JK
authors.lastname: Eriksson
authors.affiliation: Clinical Epidemiology Unit, Orthopedics, Department of Clinical Sciences Lund, Lund University, Lund, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Englund
authors.affiliation: Section of Rheumatology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden.
authors.forename: J A
authors.initials: JA
authors.lastname: Nilsson
authors.affiliation: Section of Rheumatology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden.
authors.forename: P
authors.initials: P
authors.lastname: Geborek
authors.affiliation: Department of Rheumatology and Inflammation, Research Institute of Medicine, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
authors.forename: L T H
authors.initials: LTH
authors.lastname: Jacobsson
authors.affiliation: Clinical Epidemiology Unit, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Askling
authors.affiliation: Clinical Epidemiology Unit, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Neovius
mesh_terms: D000328:Adult; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010415:Pensions; D016016:Proportional Hazards Models; D012042:Registries; D062707:Return to Work / Q000706:statistics & numerical data*; D018582:Sick Leave / Q000706:statistics & numerical data*; D013548:Sweden; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*; D055815:Young Adult
chemical_list: D018501:Antirheumatic Agents; D014409:Tumor Necrosis Factor-alpha
keywords: Anti-TNF; DMARDs (biologic); Outcomes research; Rheumatoid Arthritis; Social work