Serum leptin and risk of cognitive decline in elderly italians

J Alzheimers Dis. 2015;44(4):1231-9. doi: 10.3233/JAD-141836.


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.

Keywords: Adipokines; cognitive decline; cohort analysis; epidemiology; leptin.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Aging / blood*
  • Cognition Disorders / diagnosis
  • Female
  • Humans
  • Italy
  • Leptin / blood*
  • Longitudinal Studies
  • Male
  • Mental Status Schedule
  • Neuropsychological Tests
  • Sex Factors
  • Statistics as Topic


  • Leptin