title: The role of obesity duration on the association between obesity and risk of physical disability.
abstract: OBJECTIVE
  To relate measured obesity duration in mid-life with subsequent incidence of physical disability over and above body mass index (BMI) attained.
  
  
  METHODS
  Framingham Offspring Study is a longitudinal study that began in 1971. Examination 5 (1991-1995; "baseline") and disability onset ascertained from examinations 6-8 (2008) were used. About 2,095 disability-free participants aged 45-65 years at baseline were included. Obesity (BMI ≥ 30 kg/m(2) ) duration was calculated between examination 1 and examination 5. Cox regression was used to analyze time to disability.
  
  
  RESULTS
  204 participants developed disability (incidence rate=7.9 per 1,000 person-years). Obesity duration ranged from 0 to 22 years (mean of 2.0 years overall, 8.3 years for those with baseline obesity). Obesity duration increased risk of new disability (hazard ratio [HR] 1.07 per year of obesity; 95% confidence interval [CI] 1.05-1.09). This association was attenuated on further adjustment for baseline BMI (HR 1.03; 95% CI 1.00-1.06).
  
  
  CONCLUSIONS
  Being obese for longer during mid-life increases the risk of later-life disability over and above attained BMI. These results support the need for prevention of weight gain in young adults to avoid an increasing burden of physical disability in later life.
authors.affiliation: Obesity and Population Health, Baker IDI Heart and Diabetes Institute, Melbourne, Australia; Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia.
authors.forename: Evelyn
authors.initials: E
authors.lastname: Wong
authors.forename: Stephanie K
authors.initials: SK
authors.lastname: Tanamas
authors.forename: Rory
authors.initials: R
authors.lastname: Wolfe
authors.forename: Kathryn
authors.initials: K
authors.lastname: Backholer
authors.forename: Christopher
authors.initials: C
authors.lastname: Stevenson
authors.forename: Asnawi
authors.initials: A
authors.lastname: Abdullah
authors.forename: Anna
authors.initials: A
authors.lastname: Peeters
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001315:Australia / Q000453:epidemiology; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D004185:Disability Evaluation; D006233:Persons with Disabilities / Q000534:rehabilitation*; D005260:Female; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology / Q000534:rehabilitation*; D012189:Retrospective Studies; D055815:Young Adult