title: Lifestyle factors and incident mobility limitation in obese and non-obese older adults.
abstract: OBJECTIVE
  This study examines the association between incident mobility limitation and 4 lifestyle factors: smoking, alcohol intake, physical activity, and diet in well-functioning obese (n = 667) and non-obese (n = 2027) older adults.
  
  
  METHODS
  Data were from men and women, 70 to 79 years of age from Pittsburgh, PA and Memphis, TN, participating in the Health, Aging and Body Composition (Health ABC) study. In addition to individual lifestyle practices, a high-risk lifestyle score (0 to 4) was calculated indicating the total number of unhealthy lifestyle practices per person. Mobility limitation was defined as reported difficulty walking 1/4 mile or climbing 10 steps during two consecutive semiannual assessments over 6.5 years.
  
  
  RESULTS
  In non-obese older persons, significant risk factors for incident mobility limitation after adjustment for socio-demographics and health-related variables were current and former smoking [hazard ratio (HR) = 1.51; 95% confidence interval (CI), 1.20 to 1.89; HR = 1.40; 95% CI, 1.12 to 1.74), former alcohol intake (HR = 1.30; 95% CI, 1.05 to 1.60), low and medium physical activity (HR = 1.78; 95% CI, 1.45 to 2.18; HR = 1.29, 95% CI, 1.07 to 1.54), and eating an unhealthy diet (HR = 1.57; 95% CI, 1.17 to 2.10). In the obese, only low physical activity was associated with a significantly increased risk of mobility limitation (HR = 1.44; 95% CI, 1.08 to 1.92). Having two or more unhealthy lifestyle factors was a strong predictor of mobility limitation in the non-obese only (HR = 1.98; 95% CI, 1.61 to 2.43). Overall, obese persons had a significantly higher risk of mobility limitation compared with non-obese persons, independent of lifestyle factors (HR = 1.73; 95% CI, 1.52 to 1.96).
  
  
  CONCLUSIONS
  These results underscore the importance of a healthy lifestyle for maintaining function among non-obese older adults. However, a healthy lifestyle cannot overcome the effect of obesity in obese older adults; this stresses the importance of preventing obesity to protect against mobility loss in older persons.
authors.affiliation: Department of Health Care Studies, Medical Sociology Section, Universiteit Maastricht, Maastricht, The Netherlands. kostera@mail.nih.gov
authors.forename: Annemarie
authors.initials: A
authors.lastname: Koster
authors.forename: Brenda W J H
authors.initials: BW
authors.lastname: Penninx
authors.forename: Anne B
authors.initials: AB
authors.lastname: Newman
authors.forename: Marjolein
authors.initials: M
authors.lastname: Visser
authors.forename: Coen H
authors.initials: CH
authors.lastname: van Gool
authors.forename: Tamara B
authors.initials: TB
authors.lastname: Harris
authors.forename: Jacques Th M
authors.initials: JT
authors.lastname: van Eijk
authors.forename: Gertrudis I J M
authors.initials: GI
authors.lastname: Kempen
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Brach
authors.forename: Eleanor M
authors.initials: EM
authors.lastname: Simonsick
authors.forename: Denise K
authors.initials: DK
authors.lastname: Houston
authors.forename: Frances A
authors.initials: FA
authors.lastname: Tylavsky
authors.forename: Susan M
authors.initials: SM
authors.lastname: Rubin
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Kritchevsky
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology*; D000428:Alcohol Drinking / Q000503:physiopathology; D015331:Cohort Studies; D004032:Diet; D005260:Female; D005500:Follow-Up Studies; D015577:Geriatric Assessment; D015438:Health Behavior; D006304:Health Status; D006801:Humans; D008019:Life Style; D008137:Longitudinal Studies; D008297:Male; D051346:Mobility Limitation; D009043:Motor Activity / Q000502:physiology; D009765:Obesity / Q000209:etiology / Q000503:physiopathology* / Q000517:prevention & control; D012907:Smoking / Q000503:physiopathology