title: Long-term physical functioning and its association with somatic comorbidity and comorbid depression in patients with established rheumatoid arthritis: a longitudinal study.
abstract: OBJECTIVE
  To describe long-term physical functioning and its association with somatic comorbidity and comorbid depression in patients with established rheumatoid arthritis (RA).
  
  
  METHODS
  Longitudinal data over a period of 11 years were collected from 882 patients with RA at study inclusion. Patient-reported outcomes were collected in 1997, 1998, 1999, 2002, and 2008. Physical functioning was measured with the Health Assessment Questionnaire and the physical component summary score of the Short Form 36 health survey. Somatic comorbidity was measured by a questionnaire including 12 chronic diseases. Comorbid depression was measured with the Center for Epidemiologic Studies Depression Scale. We distinguished 4 groups of patients based on comorbidity at baseline.
  
  
  RESULTS
  Seventy-two percent of the patients at baseline were women. The mean ± SD age was 59.3 ± 14.8 years and the median disease duration was 5.0 years (interquartile range 2.0-14.0 years). For the total group of patients with RA, physical functioning improved over time. Patients with somatic comorbidity, comorbid depression, or both demonstrated worse physical functioning than patients without comorbidity at all data collection points. Both groups with comorbid depression had the lowest scores. Only patients with both somatic comorbidity and comorbid depression showed significantly less improvement in physical functioning over time.
  
  
  CONCLUSIONS
  Both somatic comorbidity and comorbid depression were negatively associated with physical functioning during an 11-year followup period. Furthermore, their combination seems to be especially detrimental to physical functioning over time. These results emphasize the need to take somatic comorbidity and comorbid depression into account in the screening and treatment of patients with RA.
authors: Amsterdam Rehabilitation Research Center, Reade, 1040 HG Amsterdam, The Netherlands. j.vd.hoek@reade.nl
authors: J
authors: J
authors: van den Hoek
authors: L D
authors: LD
authors: Roorda
authors: H C
authors: HC
authors: Boshuizen
authors: J
authors: J
authors: van Hees
authors: I
authors: I
authors: Rupp
authors: G J
authors: GJ
authors: Tijhuis
authors: J
authors: J
authors: Dekker
authors: G A M
authors: GA
authors: van den Bos
mesh_terms: D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology / Q000523:psychology; D015897:Comorbidity; D003863:Depression / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology / Q000523:psychology; D005260:Female; D006304:Health Status; D006305:Health Status Indicators; D006801:Humans; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D011795:Surveys and Questionnaires; D013997:Time Factors