title: Metabolic syndrome over 10 years and cognitive functioning in late midlife: the Whitehall II study.
abstract: OBJECTIVE
  Evidence that the metabolic syndrome is a risk factor for poor cognition is mixed and is focused mainly on the elderly population; rarely is an adjustment made for socioeconomic factors. We examined this association in late midlife, with particular focus on cumulative effects and the role of socioeconomic circumstances.
  
  
  METHODS
  Analyses were performed for 4,150 white participants from the Whitehall II study. Metabolic syndrome, using the National Cholesterol Education Program Adult Treatment Panel III criteria, was assessed three times over the 10-year follow-up (1991-2001). Cognitive function was assessed using a battery of six tests at the end of the follow-up.
  
  
  RESULTS
  After adjustment for demographic variables, health behaviors, and health status, participants with persistent metabolic syndrome (at least two of the three screenings) over the 10-year follow-up had lower cognitive performance than participants who never had metabolic syndrome. No significant differences in cognitive function were observed between participants with nonpersistent metabolic syndrome (one of the three screenings) and those who never had metabolic syndrome during the follow-up. Adjustment for adult occupational position attenuated this association by between 41 and 86%, depending on the measure of cognitive function. Adjustment for education had little effect.
  
  
  CONCLUSIONS
  Only persistent metabolic syndrome was associated with lower cognitive performance in late midlife. Adult occupational position but not education had a substantial impact on this association; these results highlight the importance of adult socioeconomic circumstances in identifying and targeting risk factors for cognitive aging.
authors.affiliation: Department of Epidemiology and Public Health, University College London, London, UK. tasnime.akbaraly@inserm.fr
authors.forename: Tasnime N
authors.initials: TN
authors.lastname: Akbaraly
authors.forename: Mika
authors.initials: M
authors.lastname: Kivimaki
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Shipley
authors.forename: Adam G
authors.initials: AG
authors.lastname: Tabak
authors.forename: Markus
authors.initials: M
authors.lastname: Jokela
authors.forename: Marianna
authors.initials: M
authors.lastname: Virtanen
authors.forename: Michael G
authors.initials: MG
authors.lastname: Marmot
authors.forename: Jane E
authors.initials: JE
authors.lastname: Ferrie
authors.forename: Archana
authors.initials: A
authors.lastname: Singh-Manoux
mesh_terms: D000328:Adult; D003072:Cognition Disorders / Q000453:epidemiology* / Q000209:etiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications* / Q000453:epidemiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D012923:Social Class; D013997:Time Factors; D044465:White People