title: Serum leptin and risk of cognitive decline in elderly italians.
abstract: BACKGROUND
  US studies suggest that leptin, a fat-derived hormone, may be protective against the development of dementia.
  
  
  OBJECTIVE
  To investigate the complex relationship between leptin levels and cognitive decline in elderly Italians.
  
  
  METHODS
  We studied circulating fasting leptin levels in 809 elderly adults free from dementia who participated in the prospective Italian population-based InCHIANTI study between 1998 and 2009 (mean follow-up of 8.0 years). Global cognitive decline was defined as a reduction of ≥5 points on the Mini-Mental State Examination (MMSE). Trail-Making Tests A and B were also incorporated, with cognitive decline defined as discontinued testing or the worst 10% of change from baseline. We also investigated whether any association could be explained by midlife weight and whether cognitive decline was associated with changing leptin levels.
  
  
  RESULTS
  The multivariate adjusted relative risk ([RR]; 95% confidence interval [CI]) of cognitive decline on the MMSE was 0.84 (95% CI 0.73-0.97) in relation to baseline sex-standardized log-leptin levels. High leptin levels showed a non-significant trend toward a reduced risk of decline on the Trail-Making Tests A (RR = 0.85, 95% CI 0.71-1.02) and B (RR = 0.90, 0.79-1.02). Adjusting for midlife weight or change in weight did not alter the pattern of results, and cognitive decline was not associated with changing leptin levels.
  
  
  CONCLUSIONS
  High leptin levels were independently associated with a reduced risk of cognitive decline in elderly Italians.
authors.affiliation: The University of Exeter Medical School, Exeter, UK.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Littlejohns
authors.affiliation: The University of Exeter Medical School, Exeter, UK.
authors.forename: Katarina
authors.initials: K
authors.lastname: Kos
authors.affiliation: The University of Exeter Medical School, Exeter, UK.
authors.forename: William E
authors.initials: WE
authors.lastname: Henley
authors.affiliation: Geriatrics, IRCCS-INRCA, Ancona, Italy (A.C.).
authors.forename: Antonio
authors.initials: A
authors.lastname: Cherubini
authors.affiliation: National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA.
authors.forename: Luigi
authors.initials: L
authors.lastname: Ferrucci
authors.affiliation: The University of Exeter Medical School, Exeter, UK.
authors.forename: Iain A
authors.initials: IA
authors.lastname: Lang
authors.affiliation: The Division of General Medicine, Veterans Affairs Ann Arbor Center for Clinical Management Research, Ann Arbor, Michigan, USA The Institute for Social Research and the Institute for Healthcare Policy and Innovation, University of Michigan, Ann Arbor, Michigan, USA.
authors.forename: Kenneth M
authors.initials: KM
authors.lastname: Langa
authors.affiliation: The University of Exeter Medical School, Exeter, UK.
authors.forename: David
authors.initials: D
authors.lastname: Melzer
authors.affiliation: The University of Exeter Medical School, Exeter, UK.
authors.forename: David J
authors.initials: DJ
authors.lastname: Llewellyn
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood*; D003072:Cognition Disorders / Q000175:diagnosis; D005260:Female; D006801:Humans; D007558:Italy; D020738:Leptin / Q000097:blood*; D008137:Longitudinal Studies; D008297:Male; D008609:Mental Status Schedule; D009483:Neuropsychological Tests; D012737:Sex Factors; D013223:Statistics as Topic
chemical_list: D020738:Leptin
keywords: Adipokines; cognitive decline; cohort analysis; epidemiology; leptin