title: The offspring of people with a total knee replacement for severe primary knee osteoarthritis have a higher risk of worsening knee pain over 8 years.
abstract: OBJECTIVE
  To investigate whether offspring having at least one parent with a total knee replacement for severe primary knee osteoarthritis (OA) have an increased risk of worsening knee pain over 8 years as compared with controls with no family history of knee OA.
  
  
  METHODS
  A total of 219 participants (mean age 48 years, range 29-61 years) with 115 offspring and 104 controls participated in this study. Knee pain was respectively assessed using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at 2 years and 10 years. T1-weighted or T2-weighted fat saturated MRI of the right knee was performed to assess knee cartilage defects, bone marrow lesions, effusion, meniscal extrusion and tears.
  
  
  RESULTS
  Compared with controls, the prevalence of knee pain for offspring was similar at 2 years (56% vs 54%, p=0.764) and higher at 10 years (74% vs 54%, p=0.002). Over 8 years, offspring more frequently had an increase in total knee pain (66% vs 41% ≥1 point increase, p=0.003) and in all subscales apart from walking (all p<0.05). In multivariable analysis, after adjustment for confounders and structural factors, offspring had an elevated risk of worsening total knee pain (OR=2.16, 95% CI 1.14 to 4.12), as well as each subscale except for walking and standing (OR=1.95 to 3.30, all p<0.05).
  
  
  CONCLUSIONS
  Offspring with a family history of knee OA have an increased risk of worsening knee pain, which is independent of structural factors, suggesting that genetic factors may be involved in the pathogenesis of knee pain.
authors.affiliation: Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Feng
authors.initials: F
authors.lastname: Pan
authors.affiliation: Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Changhai
authors.initials: C
authors.lastname: Ding
authors.affiliation: Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Tania
authors.initials: T
authors.lastname: Winzenberg
authors.affiliation: Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Hussain
authors.initials: H
authors.lastname: Khan
authors.affiliation: Osteoarthritis Research Unit, University of Montreal Hospital Research Centre (CRCHUM), Montreal, Quebec, Canada.
authors.forename: Johanne
authors.initials: J
authors.lastname: Martel-Pelletier
authors.affiliation: Osteoarthritis Research Unit, University of Montreal Hospital Research Centre (CRCHUM), Montreal, Quebec, Canada.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Pelletier
authors.affiliation: Department of Epidemiology and Preventive Medicine, Monash University Medical School, Melbourne, Victoria, Australia.
authors.forename: Flavia
authors.initials: F
authors.lastname: Cicuttini
authors.affiliation: Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Graeme
authors.initials: G
authors.lastname: Jones
mesh_terms: D000328:Adult; D032721:Adult Children; D018771:Arthralgia / Q000235:genetics* / Q000473:pathology; D019645:Arthroplasty, Replacement, Knee; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D007719:Knee Joint; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000235:genetics* / Q000601:surgery; D012307:Risk Factors; D013997:Time Factors
keywords: Epidemiology; Knee Osteoarthritis; Magnetic Resonance Imaging