title: Determinants of pain and functioning in knee osteoarthritis: a one-year prospective study.
abstract: OBJECTIVE
  To identify predictors of pain and disability in knee osteoarthritis.
  
  
  METHODS
  A one-year prospective analysis of determinants of pain and functioning in knee osteoarthritis.
  
  
  METHODS
  Primary care providers in a medium-sized city.
  
  
  METHODS
  A total of 111 patients aged from 35 to 75 with clinical symptoms and radiographic grading (Kellgren-Lawrence 2-4) of knee osteoarthritis who participated in a randomized controlled trial.
  
  
  METHODS
  The outcome measures were self-reported pain and function, which were recorded at 0, 3 and 12 months. Disease-specific pain and functioning were assessed using the pain and function subscales of the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index. Generic physical and mental functioning were assessed using the RAND-36 subscales for function, and physical and mental component summary scores. Possible baseline predictors for these outcomes were 1) demographic, socioeconomic and disease-related variables, and 2) psychological measures of resources, distress, fear of movement and catastrophizing.
  
  
  RESULTS
  Multivariate linear mixed model analyses revealed that normal mood at baseline measured with the Beck Anxiety Inventory predicted significantly better results in all measures of pain (WOMAC P=0.02) and function (WOMAC P=0.002, RAND-36 P=0.002) during the one-year follow-up. Psychological resource factors (pain self-efficacy P=0.012, satisfaction with life P=0.002) predicted better function (RAND-36). Pain catastrophizing predicted higher WOMAC pain levels (P=0.013), whereas fear of movement (kinesiophobia) predicted poorer functioning (WOMAC P=0.046, RAND-36 P=0.024).
  
  
  CONCLUSIONS
  Multiple psychological factors in people with knee osteoarthritis pain are associated with the development of disability and longer term worse pain.
authors: Department of Physical and Rehabilitation Medicine, Kuopio University Hospital, Finland Psychiatry, Department of Social Services and Health Care, City of Helsinki Health Care, Finland eeva-eerika.helminen@fimnet.fi.
authors: Eeva-Eerika
authors: EE
authors: Helminen
authors: School of Educational Sciences and Psychology, University of Eastern Finland, Finland.
authors: Sanna H
authors: SH
authors: Sinikallio
authors: Department of Psychiatry, Addiction Psychiatry Outpatient Clinic, Kuopio University Hospital, Finland.
authors: Anna L
authors: AL
authors: Valjakka
authors: Department of Physical and Rehabilitation Medicine, Kuopio University Hospital, Finland.
authors: Rauni H
authors: RH
authors: Väisänen-Rouvali
authors: Department of Physical and Rehabilitation Medicine, Kuopio University Hospital, Finland Institute of Clinical Medicine, University of Eastern Finland, Finland.
authors: Jari Pa
authors: JP
authors: Arokoski
mesh_terms: D000328:Adult; D000339:Affect; D000368:Aged; D015928:Cognitive Behavioral Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009864:Ontario; D020370:Osteoarthritis, Knee / Q000150:complications* / Q000503:physiopathology* / Q000523:psychology; D010146:Pain / Q000175:diagnosis / Q000209:etiology* / Q000523:psychology; D059408:Pain Management / Q000379:methods; D010147:Pain Measurement; D011446:Prospective Studies; D020127:Recovery of Function; D057566:Self Report
keywords: Knee osteoarthritis; disability; pain; predictors; psychological factors