title: Association of radiographic and symptomatic knee osteoarthritis with health-related quality of life in a population-based cohort study in Japan: the ROAD study.
abstract: OBJECTIVE
  Knee osteoarthritis (OA) is a major public health issue causing chronic pain and disability. However, there is little information on the impact of this disease on quality of life (QOL) in Japanese men and women. The objective of the present study was to clarify the impact of radiographic and symptomatic knee OA on QOL in Japan.
  
  
  METHODS
  This study examined the association of radiographic and symptomatic knee OA with QOL parameters such as the Medical Outcomes Study Short Form-8 (SF-8), EuroQOL (EQ-5D) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Radiographic knee OA was defined according to Kellgren/Lawrence (KL) grades, and symptomatic knee OA was defined as KL=3 or 4 with knee pain. We also examined the independent association of symptomatic knee OA and grip strength with QOL.
  
  
  RESULTS
  From the 3040 participants in the Research on Osteoarthritis Against Disability (ROAD) study, the present study analyzed 2126 subjects older than 40 years who completed the questionnaires (767 men and 1359 women; mean age, 68.9+/-10.9 years). Subjects with KL=3 or 4 had significantly lower physical QOL as measured by the physical component summary (PCS) score of the SF-8 and pain domains of the WOMAC, whereas mental QOL, as measured by the mental component summary (MCS) score of the SF-8, was higher in subjects with KL=3 or 4 than KL=0 or 1. Symptomatic knee OA was significantly more likely than radiographic knee OA without pain to be associated with physical QOL loss as measured by the PCS score and physical domains of the WOMAC. Symptomatic knee OA and grip strength were independently associated with physical QOL.
  
  
  CONCLUSIONS
  This cross-sectional study revealed that subjects with symptomatic knee OA had significantly lower physical QOL than subjects without it.
authors.affiliation: Department of Clinical Motor System Medicine, 22nd Century Medical and Research Center, Faculty of Medicine, The University of Tokyo, Tokyo, Japan. murakis-ort@h.u-tokyo.ac.jp
authors.forename: S
authors.initials: S
authors.lastname: Muraki
authors.forename: T
authors.initials: T
authors.lastname: Akune
authors.forename: H
authors.initials: H
authors.lastname: Oka
authors.forename: Y
authors.initials: Y
authors.lastname: En-yo
authors.forename: M
authors.initials: M
authors.lastname: Yoshida
authors.forename: A
authors.initials: A
authors.lastname: Saika
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: H
authors.initials: H
authors.lastname: Yoshida
authors.forename: H
authors.initials: H
authors.lastname: Ishibashi
authors.forename: F
authors.initials: F
authors.lastname: Tokimura
authors.forename: S
authors.initials: S
authors.lastname: Yamamoto
authors.forename: K
authors.initials: K
authors.lastname: Nakamura
authors.forename: H
authors.initials: H
authors.lastname: Kawaguchi
authors.forename: N
authors.initials: N
authors.lastname: Yoshimura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D015331:Cohort Studies; D005260:Female; D006304:Health Status; D006306:Health Surveys; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000503:physiopathology*; D017063:Outcome Assessment, Health Care; D010146:Pain / Q000523:psychology; D010147:Pain Measurement; D011788:Quality of Life; D011859:Radiography; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D055815:Young Adult