title: Work ability in rheumatoid arthritis patients: a register study on the prospective risk of exclusion and probability of returning to work.
abstract: The aim was to study work ability in patients with RA compared with the general population by investigating the rates and risks of long-term sickness absence, unemployment and disability pension, and the chance of returning to work and the changes in these risks over time (1994-2011).
  
  
  
  This was a cohort study with up to 17 years of follow-up (mean 6.95 years/person) including 6677 RA patients of working age (identified in the nationwide DANBIO registry) and 56 955 matched controls from the general population. A multi-state model was used to analyse all shifts between the work-related states (long-term sickness absence, unemployment and disability pension, as well as the chance of returning to work) and calculate hazard rates (HRs). Analyses were stratified by disease duration and controlled for socio-demographic factors, physical job exposure and somatic and psychiatric co-morbidities.
  
  
  
  RA patients had increased risk of long-term sickness absence (e.g. early RA: HR = 4.00, 95% CI: 3.64, 4.30) and disability pension (e.g. established RA: HR = 2.75, 95% CI: 2.54, 2.98) relative to controls. From 1994-99 to 2006-11, a decrease in the effect of established RA was observed [long-term sickness absence: from HR = 2.25 (95% CI: 1.99, 2.54) to 1.63 (95% CI: 1.51, 1.75); and disability pension: from HR = 3.49 (95% CI: 2.83, 4.32) to 2.40 (95% CI: 2.15, 2.69)]. RA patients had a lower chance of returning to work from long-term sickness absence or unemployment (HR = 0.60, HR=0.80), and this did not change over time.
  
  
  
  RA patients remain at high risk for long-term sickness absence and disability pension, despite a positive development between 1996-99 and 2006-11. Returning to work after sick leave or unemployment remains a challenge for RA patients.
authors.affiliation: National Research Centre for the Working Environment, Copenhagen.|The DANBIO registry, Center for Rheumatology and Spine Diseases, Rigshospitalet, Glostrup.|Copenhagen Center for Arthritis Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Glostrup.
authors.forename: Sofie M
authors.initials: SM
authors.lastname: Hansen
authors.affiliation: The DANBIO registry, Center for Rheumatology and Spine Diseases, Rigshospitalet, Glostrup.|Copenhagen Center for Arthritis Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Glostrup.|Institute for Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen.
authors.forename: Merete Lund
authors.initials: ML
authors.lastname: Hetland
authors.affiliation: National Research Centre for the Working Environment, Copenhagen.
authors.forename: Jacob
authors.initials: J
authors.lastname: Pedersen
authors.affiliation: Copenhagen Center for Arthritis Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Glostrup.|Institute for Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen.
authors.forename: Mikkel
authors.initials: M
authors.lastname: Østergaard
authors.affiliation: Department of Occupational and Environmental Medicine, Bispebjerg Hospital, Copenhagen.
authors.forename: Tine Steen
authors.initials: TS
authors.lastname: Rubak
authors.affiliation: National Research Centre for the Working Environment, Copenhagen.|Optum Outcomes, Lincoln, RI, USA.|Department of Public Health, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Jakob Bue
authors.initials: JB
authors.lastname: Bjorner
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000175:diagnosis*; D016022:Case-Control Studies; D015331:Cohort Studies; D003718:Denmark; D004185:Disability Evaluation; D004651:Employment / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D018868:Insurance, Disability / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D016272:Occupational Health; D011237:Predictive Value of Tests; D012016:Reference Values; D012042:Registries; D012189:Retrospective Studies; D062707:Return to Work / Q000706:statistics & numerical data; D018570:Risk Assessment; D018582:Sick Leave / Q000706:statistics & numerical data*; D018434:Sickness Impact Profile; D013647:Task Performance and Analysis; D014478:Unemployment / Q000706:statistics & numerical data
keywords: Cox proportional hazards model; disability pension; multi-state model; registry; return to work; rheumatoid arthritis; sick leave; unemployment