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Background: Resveratrol may play a protective role against the frailty syndrome (FS) because of its antioxidant and anti-inflammatory properties. Objective: We prospectively evaluated the association between habitual dietary resveratrol exposure and the development of FS after 3-, 6-, and 9-y follow-up periods in a community-dwelling older population. Design: We conducted a longitudinal analysis with the use of data from 769 participants aged $65 y from the Invecchiare in Chianti (Aging in Chianti) study. Total dietary resveratrol (TDR) intake was estimated at baseline with the use of a validated food-frequency questionnaire, which was developed to assess participants' usual food intakes over the previous year, and an ad hoc resveratrol database. Total urinary resveratrol (TUR) was analyzed with the use of liquid chromatography-tandem mass spectrometry with a previous solid-phase extraction at baseline. The combination of both measures [total dietary resveratrol plus total urinary resveratrol (TDR +TUR)] was computed with the use of the Howe's method. FS was assessed at baseline and at 3-, 6-, and 9-y of follow-up and was defined as the presence of ≥3 of the following 5 criteria: shrinking, exhaustion, sedentariness, slowness, and weakness. Results: TDR+TUR concentrations were inversely associated with FS risk over 3-y of follow-up (OR for comparison of extreme tertiles: 0.11; 95% CI: 0.03, 0.45; P-trend = 0.002) but not after 6- and 9-y of follow-up in multinomial logistic regression models adjusted for baseline frailty status and potential confounders. These results did not differ when analyses were further adjusted for inflammatory markers. Conclusion: Higher habitual dietary resveratrol exposure was associated with lower risk of older community dwellers developing FS during the first 3 y of follow-up but not after longer follow-up periods. [ABSTRACT FROM AUTHOR]

Objectives To investigate the association between total urinary polyphenols ( TUPs) and total dietary polyphenols ( TDPs) and cognitive decline in an older population. Design The Invecchiare in Chianti ( In CHIANTI) study, a cohort study with 3 years of follow-up. Setting Tuscany, Italy. Participants Individuals without dementia aged 65 and older (N = 652). Measurements 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. Conclusion 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. [ABSTRACT FROM AUTHOR]

Background: Frailty, an age-related state of increased vulnerability, is associated with a higher risk of multiple adverse events. Studies have suggested that the quality of dietary intake may affect the development of frailty. We hypothesized that frailty in older subjects would be associated with dietary total polyphenols (DTP) intake and its biomarker, urinary total polyphenols (UTP)., Methods: The Invecchiare in Chianti (InCHIANTI) Study is a prospective cohort study set in the Chianti area (Italy). We used data at baseline from 811 participants aged 65 years and older. UTP was determined using the Folin-Ciocalteu assay after solid-phase extraction. DTP was estimated using a validated Food Frequency Questionnaire and our own polyphenol database. The frailty, prefrailty, and nonfrailty states were defined according to the Fried and colleagues' criteria. Multinomial logistic regressions adjusted for potential confounders were used to assess the relationship between polyphenols and frailty., Results: Both DTP and UTP concentrations progressively decrease from nonfrail to frail participants. Participants in the highest UTP tertile compared to those in the lowest tertile were significantly less likely to be both frail (odds ratio [OR] = 0.36 [0.14-0.88], p = .025) and prefrail (OR = 0.64 [0.42-0.98], p = .038). Exhaustion and slowness were the only individual frailty criteria significantly associated with UTP tertiles. No significant association was observed between frailty and DTP, after adjustment for covariates., Conclusions: High concentrations of UTP were associated with lower prevalence of frailty and prefrailty in an older community-dwelling population. A polyphenol-rich diet may protect against frailty in older persons. Our findings should be confirmed in longitudinal studies., (© The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Polyphenols have beneficial effects on several chronic diseases but assessing polyphenols intake from self-reported dietary questionnaires tends to be inaccurate and not very reliable. A promising alternative is to use urinary excretion of polyphenols as a proxy measure of intake. The best method to assess urinary excretion is to collect 24-h urine. However, since collecting 24-h urine method is expensive, time consuming and may be difficult to implement in large population-based studies, measures obtained from spot urine normalized by creatinine are commonly used. The purpose of the study was to evaluate the correlation between polyphenols dietary intake and total urinary polyphenol excretion (TPE), expressed by both 24-h volume and urinary creatinine normalization in 928 participants from the InCHIANTI study. Dietary intake data were collected using a validated food frequency questionnaire. Urinary TPE was analyzed by Folin-Ciocalteau assay. Both urinary TPE expression models were statistically correlated (r=0.580), and the partial correlation coefficient improved (pr=0.722) after adjusting for the variables that modify the urinary creatinine excretion (i.e. gender, age, BMI, physical activity and renal function). In crude models, polyphenol intake was associated with TPE corrected by 24-h volume (r=0.211; P<0.001), but not with creatinine normalization (r=0.014; P=0.692). However, urinary TPE expressed by creatinine correction was significantly correlated with dietary polyphenols after adjusting for covariates (pr=0.113; P=0.002). We conclude that urinary TPE expressed by 24-h volume is a better biomarker of polyphenol dietary intake than by urinary creatinine normalization. After covariate adjustment, both can be used for studying the relationships between polyphenol intake and health in large-scale epidemiological studies., Competing Interests: The authors are not aware of any conflict of interest., (Copyright © 2011 Elsevier B.V. All rights reserved.)