title: Socio-economic disadvantage from childhood to adulthood and locomotor function in old age: a lifecourse analysis of the Boyd Orr and Caerphilly prospective studies.
abstract: BACKGROUND
  Socio-economic influences over a lifetime impact on health and may contribute to poor physical functioning in old age.
  
  
  METHODS
  The authors examined the impact of both childhood and adulthood socio-economic factors on locomotor function at 63-86 years (measured with the get up and go timed walk and flamingo balance test) in the UK-based Boyd Orr (n=405) and Caerphilly (n=1196) prospective cohorts.
  
  
  RESULTS
  There was a marked reduction in walking speed and balance time with increasing age. Each year of age was associated with a 1.7% slower walk time and a 14% increased odds of poor balance. Participants who moved from a low socio-economic position in childhood to a high socio-economic position in adulthood had 3% slower walking times (95% CI -2% to 8%) than people with a high socio-economic position in both periods. Participants who moved from a high socio-economic position in childhood to a low adulthood socio-economic position had 5% slower walking times (95% CI -2% to 12%). Participants with a low socio-economic position in both periods had 10% slower walking times (95% CI 5% to 16%; p for trend <0.001). In Boyd Orr, low socio-economic position in childhood was associated with poor balance in old age (OR per worsening category=1.26; 95% CI 1.01 to 1.57; p=0.043), as was socio-economic position in adulthood (OR=1.71; 95% CI 1.20 to 2.45; p=0.003). Similar associations were not observed in Caerphilly.
  
  
  CONCLUSIONS
  Accumulating socio-economic disadvantage from childhood to adulthood is associated with slower walking time in old age, with mixed results for balance ability.
authors.affiliation: Department of Social Medicine, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol BS8 2PS, UK. kate.birnie@bristol.ac.uk
authors.forename: Kate
authors.initials: K
authors.lastname: Birnie
authors.forename: Richard M
authors.initials: RM
authors.lastname: Martin
authors.forename: John
authors.initials: J
authors.lastname: Gallacher
authors.forename: Antony
authors.initials: A
authors.lastname: Bayer
authors.forename: David
authors.initials: D
authors.lastname: Gunnell
authors.forename: Shah
authors.initials: S
authors.lastname: Ebrahim
authors.forename: Yoav
authors.initials: Y
authors.lastname: Ben-Shlomo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D011446:Prospective Studies; D012923:Social Class; D006113:United Kingdom