Low Levels of a Urinary Biomarker of Dietary Polyphenol Are Associated with Substantial Cognitive Decline over a 3-Year Period in Older Adults: The Invecchiare in Chianti Study.
OBJECTIVE
To investigate the association between total urinary polyphenols (TUPs) and total dietary polyphenols (TDPs) and cognitive decline in an older population.


METHODS
The Invecchiare in Chianti (InCHIANTI) study, a cohort study with 3 years of follow-up.


METHODS
Tuscany, Italy.


METHODS
Individuals without dementia aged 65 and older (N=652).


METHODS
TUP and TDP concentrations were analyzed at baseline using the Folin-Ciocalteu assay and a validated food frequency questionnaire, respectively. Cognition was assessed using the Mini-Mental State Examination (MMSE) and Trail-Making Test (TMT) at baseline and after 3 years of follow-up. Substantial cognitive decline was defined as a reduction in MMSE score of three or more points and an increase of at least 29 seconds on the TMT Part A (TMT-A) and 68 seconds on the TMT Part B (TMT-B) (the worst 10% of the distribution of decline) or as test discontinued because of multiple mistakes on the TMT A and B at follow-up.


RESULTS
Higher TUP levels were associated with lower risk of substantial cognitive decline on the MMSE (odds ratio (OR) comparing extreme tertiles=0.53, 95% confidence interval (CI)=0.34-0.85, P-trend=.008) and on the TMT-A (OR=0.52, 95% CI=0.28-0.96, P-trend=.03), but not on TMT-B in a logistic regression model that adjusted for baseline cognitive score and potential confounding factors. TDP did not affect the development of substantial cognitive decline in either test.


CONCLUSIONS
High concentrations of polyphenols, a nutritional biomarker of polyphenol intake, were associated with lower risk of substantial cognitive decline in an older population studied over a 3-year period, suggesting a protective effect against cognitive impairment.
Biomarkers & Nutrimetabolomic Lab., Nutrition and Food Science Department, XaRTA, INSA, Campus Torribera, Pharmacy Faculty, University of Barcelona, Barcelona, Spain.
Montserrat
M
Rabassa
Geriatrics and Emergency Care, Italian National Research Centre on Aging, Ancona, Italy.
Antonio
A
Cherubini
Biomarkers Group, Nutrition and Metabolism Section, International Agency for Research on Cancer, Lyon, France.
Raul
R
Zamora-Ros
Biomarkers & Nutrimetabolomic Lab., Nutrition and Food Science Department, XaRTA, INSA, Campus Torribera, Pharmacy Faculty, University of Barcelona, Barcelona, Spain.
Mireia
M
Urpi-Sarda
Geriatric Rehabilitation Unit, Azienda Sanitaria Firenze, Florence, Italy.
Stefania
S
Bandinelli
Clinical Research Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland.
Luigi
L
Ferrucci
Biomarkers & Nutrimetabolomic Lab., Nutrition and Food Science Department, XaRTA, INSA, Campus Torribera, Pharmacy Faculty, University of Barcelona, Barcelona, Spain.
Cristina
C
Andres-Lacueva
D000368:Aged; D015415:Biomarkers / Q000652:urine; D003072:Cognition Disorders / Q000652:urine*; D015331:Cohort Studies; D004032:Diet; D005260:Female; D006801:Humans; D007558:Italy; D008297:Male; D059808:Polyphenols / Q000652:urine*; D011446:Prospective Studies; D013997:Time Factors
D015415:Biomarkers; D059808:Polyphenols
biomarker; cognitive decline; dietary polyphenols; epidemiology; urinary polyphenols