title: Multidimensional Model of Disability and Role Functioning in Rheumatoid Arthritis.
abstract: OBJECTIVE
  To examine a model addressing the roles of rheumatoid arthritis (RA) disease burden, mood disturbance, and disability as determinants of impairments in role functioning.
  
  
  METHODS
  In a cross-sectional design, 103 RA patients recruited from the community to participate in a clinical trial completed assessments of self-assessed disease burden (total joint pain and disease activity), mood disturbance (Center for Epidemiological Studies Depression Scale depressed mood, somatic symptoms, lack of positive affect, and interpersonal problems), disability (Health Assessment Questionnaire disability index gross and fine motor), and role functioning (Short Form 36 health survey physical and social). Structural equation modeling (SEM) was used to examine direct and indirect mechanisms linking disease burden to role functioning.
  
  
  RESULTS
  SEM results indicated that the model had excellent fit: S-Bχ(2)(30) = 38.59, P = 0.135; comparative fit index = 0.977, standardized root mean residual = 0.062, and root mean square error of approximation = 0.053. Mediational analyses demonstrated that, while disease burden was associated with poor role functioning, its effects were jointly mediated by mood disturbance and disability. After the effects of mood disturbance and disability were taken into account, the effect of disease burden on role functioning was not significant.
  
  
  CONCLUSIONS
  The results indicate that mood disturbance and disability may serve as important pathways through which RA disease burden affects role functioning. Future longitudinal research is suggested to replicate these findings and further explore the mediational mechanisms examined in this study.
authors.affiliation: Cousins Center for Psychoneuroimmunology, David Geffen School of Medicine, University of California, Los Angeles.
authors.forename: Sarah R
authors.initials: SR
authors.lastname: Ormseth
authors.affiliation: Loma Linda University, Loma Linda, California.
authors.forename: Taylor L
authors.initials: TL
authors.lastname: Draper
authors.affiliation: Cousins Center for Psychoneuroimmunology, David Geffen School of Medicine, University of California, Los Angeles.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Irwin
authors.affiliation: Cedars Sinai Medical Center, Los Angeles, California.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Weisman
authors.affiliation: Loma Linda University, Loma Linda, California.
authors.forename: Adam E
authors.initials: AE
authors.lastname: Aréchiga
authors.affiliation: University of Washington School of Medicine, Seattle.
authors.forename: Narineh
authors.initials: N
authors.lastname: Hartoonian
authors.affiliation: California School of Professional Psychology of Alliant International University, Alhambra.
authors.forename: Thuy
authors.initials: T
authors.lastname: Bui
authors.affiliation: Cousins Center for Psychoneuroimmunology, David Geffen School of Medicine, University of California, Los Angeles.
authors.forename: Perry M
authors.initials: PM
authors.lastname: Nicassio
mesh_terms: D000328:Adult; D000339:Affect; D000368:Aged; D018771:Arthralgia / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D001172:Arthritis, Rheumatoid / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D017281:Cost of Illness; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D019964:Mood Disorders / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D009043:Motor Activity; D010147:Pain Measurement; D011237:Predictive Value of Tests; D011379:Prognosis; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires