title: Weight change and change in tibial cartilage volume and symptoms in obese adults.
abstract: BACKGROUND
  There is a paucity of data examining the effects of weight change on knee joint structures and symptoms. This study examined the effect of weight change on change in knee cartilage volume and symptoms in an obese cohort.
  
  
  METHODS
  112 obese subjects (Body Mass Index ≥30 kg/m(2)) were recruited from various community sources to examine the effect of obesity on musculoskeletal health. Tibial cartilage volume, determined by MRI, and knee symptoms, determined by the Western Ontario and McMaster Osteoarthritis Index (WOMAC) were collected at baseline and an average of 2.3 years later.
  
  
  RESULTS
  Percentage weight change was associated with change in medial tibial cartilage volume (β -1.2 mm(3), 95% CI -2.3 to -0.1 mm(3), p=0.03) that was consistent throughout the spectrum of weight loss through to mild weight gain. Percentage weight change was not associated with change in the lateral tibial (p=0.93) or patella (p=0.32) cartilage volumes. Percentage weight change was associated with change in all WOMAC subscales (all p≤0.01): pain (β -1.8 mm, 95% CI -3.2 to -0.4 mm), stiffness (β -1.6 mm, 95% CI -2.5 to -0.7 mm) and function (β -6.9 mm, 95% CI -11.6 to -2.1 mm).
  
  
  CONCLUSIONS
  The linearity of effect implies that weight loss is associated with reduced medial cartilage volume loss and improved knee symptoms, while weight gain is associated with increased medial cartilage volume loss and worse knee symptoms. These results suggest that in obese people, small amounts of weight change may have the potential for a disease modifying effect on both knee joint structure and symptoms. While weight loss is an important primary management strategy in obese individuals, avoidance of further weight gain should also be a clinical goal.
authors: Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Alfred Hospital, Melbourne, Victoria, Australia.
authors: Andrew J
authors: AJ
authors: Teichtahl
authors: Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Alfred Hospital, Melbourne, Victoria, Australia.
authors: Anita E
authors: AE
authors: Wluka
authors: Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Alfred Hospital, Melbourne, Victoria, Australia.
authors: Stephanie K
authors: SK
authors: Tanamas
authors: Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Alfred Hospital, Melbourne, Victoria, Australia.
authors: Yuanyuan
authors: Y
authors: Wang
authors: Department of Medicine, Monash University, Melbourne, Victoria, Australia.
authors: Boyd J
authors: BJ
authors: Strauss
authors: Department of Medicine, University of Melbourne, Austin Health, Melbourne, Victoria, Australia.
authors: Joseph
authors: J
authors: Proietto
authors: Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia.
authors: John B
authors: JB
authors: Dixon
authors: Menzies Research Institute, Hobart, Tasmania, Australia.
authors: Graeme
authors: G
authors: Jones
authors: Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Alfred Hospital, Melbourne, Victoria, Australia.
authors: Andrew
authors: A
authors: Forbes
authors: Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Alfred Hospital, Melbourne, Victoria, Australia.
authors: Flavia M
authors: FM
authors: Cicuttini
mesh_terms: D000328:Adult; D050110:Bariatric Surgery; D002358:Cartilage, Articular / Q000473:pathology*; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000453:epidemiology / Q000473:pathology*; D007719:Knee Joint / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008592:Menisci, Tibial / Q000473:pathology*; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology / Q000628:therapy*; D009929:Organ Size; D000070600:Tibial Meniscus Injuries; D015431:Weight Loss; D061217:Weight Reduction Programs