title: Overweight in midlife is related to lower cognitive function 30 years later: a prospective study with longitudinal assessments.
abstract: OBJECTIVE
  To examine if the body mass index (BMI) in midlife is related to cognitive function 30 years later in a dementia-free sample.
  
  
  METHODS
  BMI was reported in 1963 at age 50-60 years, and cognitive abilities were examined 30 years later in a longitudinal design with 5 measurement occasions at 2-year intervals (n = 417). The cognitive abilities examined included tests of long-term memory, short-term memory, speed, verbal and spatial ability.
  
  
  RESULTS
  Multilevel modeling adjusting for demographic and lifestyle factors, and relevant diseases showed that a higher BMI in midlife predicted lower test performance 30 years later. Significant associations between BMI and level of performance were found in all cognitive abilities; however, a higher midlife BMI was not associated with steeper cognitive decline.
  
  
  CONCLUSIONS
  Our results indicate that midlife overweight is related to lower overall cognitive function in old age. The fact that BMI-related effects were noted in mean-level cognitive performance, whereas only one ability showed differences in slopes, suggests that the negative effect of overweight has an onset before the entry into very old age.
authors.affiliation: Department of Psychology, University of Gothenburg, Gothenburg, Sweden. Linda.Hassing@psy.gu.se
authors.forename: Linda B
authors.initials: LB
authors.lastname: Hassing
authors.forename: Anna K
authors.initials: AK
authors.lastname: Dahl
authors.forename: Nancy L
authors.initials: NL
authors.lastname: Pedersen
authors.forename: Boo
authors.initials: B
authors.lastname: Johansson
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D015992:Body Mass Index; D003071:Cognition / Q000502:physiology*; D003072:Cognition Disorders / Q000453:epidemiology*; D015331:Cohort Studies; D015897:Comorbidity; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D055361:Multilevel Analysis; D050177:Overweight / Q000453:epidemiology*; D011159:Population Surveillance; D012042:Registries; D013548:Sweden / Q000453:epidemiology