Abstract
IMPORTANCE: The decline in physical performance that occurs in many older subjects is a strong predictor of falls, hospitalization, institutionalization and mortality. Polyphenols are bioactive compounds that may play a preventive role against physical performance decline due to their antioxidant and anti-inflammatory properties. OBJECTIVE: To investigate the association between total urinary polyphenols (TUP) and total dietary polyphenols (TDP) and substantial physical performance decline over a nine-year period among older subjects. METHODS: This longitudinal study included 368 participants aged 65 years or older from the InCHIANTI (Invecchiare in Chianti) study, an Italian population-based cohort. TUP and TDP concentrations were assessed at baseline using the Folin-Ciocalteau (F-C) assay and a validated food frequency questionnaire, respectively. Physical performance was objectively measured at baseline and at nine-year follow-up using the Short Physical Performance Battery (SPPB). A substantial decline in physical performance was considered as a decrease of three or more points in the SPPB score. RESULTS: At the nine-year follow-up assessment, 71 participants had suffered a substantial decline in physical performance. In the fully adjusted logistic regression model, participants in the highest TUP tertile had a lower risk of substantial decline in physical performance than those in the lowest tertile (OR, 0.40; 95% CI, 0.17-0.93; P trend=0.033). However, no significant association between TDP intake and physical performance decline was observed. CONCLUSION: This study shows that high TUP concentrations, a biomarker of polyphenol-rich exposure, were associated with lower risk of substantial decline in physical performance in community-dwelling older subjects over a nine-year period. These results suggest that a polyphenol-rich diet may play a role in protecting against physical performance decline in older people.