title: Insulinlike growth factor-1, insulinlike growth factor binding protein-1, and cognitive function in older men and women.
abstract: OBJECTIVE
  To assess the association between insulinlike growth factor (IGF)-1 and IGF binding protein (IGFBP)-1 with three cognitive function tests in a healthy elderly population.
  
  
  METHODS
  Cross-sectional analyses from the Rancho Bernardo Cohort Study.
  
  
  METHODS
  Southern California community of Rancho Bernardo.
  
  
  METHODS
  Men (n=636) and women (n=899) from the Rancho Bernardo study (median age 74) were assessed between 1988 and 1992 for cognitive function using the Mini-Mental State Examination (MMSE), Verbal Fluency (VF) test, and Trail-Making Test Part B (Trails B). Blood samples were obtained at the same time for IGF-1 and IGFBP-1 levels. The association between biomarkers and cognitive function tests was assessed by dichotomizing tests at the clinically relevant cutoff using logistic regression and according to tertiles and continuous IGF-1 and IGFBP-1 levels using multivariate linear regression analyses.
  
  
  RESULTS
  The mean MMSE, VF and Trails B scores indicated better cognitive function with higher IGF-1 tertile. Multivariate analyses showed that VF and MMSE were each significantly associated with IGF-1 in a dose-response manner for men (P for trend=.001), but no cognitive function tests were related to IGF-1 in women. For men, the highest IGFBP-1 tertile was inversely and significantly different from the lowest tertile for the MMSE test only (P for trend=.02).
  
  
  CONCLUSIONS
  IGF-1 was independently and positively related to MMSE and VF in men, and IGFBP-1 was inversely associated with MMSE in men. Sex differences in the association should be further investigated.
authors.affiliation: Department of Family and Preventive Medicine, School of Medicine, University of California at San Diego, La Jolla, California 92093, USA. waldelaimy@ucsd.edu
authors.forename: Wael K
authors.initials: WK
authors.lastname: Al-Delaimy
authors.forename: Denise
authors.initials: D
authors.lastname: von Muhlen
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Barrett-Connor
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood*; D003071:Cognition; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D018969:Insulin-Like Growth Factor Binding Proteins / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D012044:Regression Analysis
chemical_list: D015415:Biomarkers; D018969:Insulin-Like Growth Factor Binding Proteins; D007334:Insulin-Like Growth Factor I