Total urinary polyphenols and longitudinal changes of bone properties. The InCHIANTI study

Abstract

SummaryThe aim of this study was to evaluate the association of levels of urinary total polyphenols considered as a proxymeasure of polyphenol intake, with longitudinal changes of bone properties, in the InCHIANTI study. Dietary intake ofpolyphenols appears to be associated with future accelerated deterioration of bone health.IntroductionPolyphenols, micronutrients ingested through plant-based foods, have antioxidant and anti-inflammatory propertiesand may contribute to osteoporosis prevention. We evaluated associations of high levels of urinary total polyphenols (UTP), aproxy measure of polyphenol intake, with longitudinal changes of bone properties in a representative cohort of free-livingparticipants of the InCHIANTI study.MethodsThe InCHIANTI study enrolled representative samples from the registry list of two towns in Tuscany, Italy. Baselinedata were collected in 1998 and follow-up visits in 2001 and 2004. Of the 1453 participants enrolled, 956 consented to donate a24-h urine sample used to assess UTP, had dietary assessment, a physical examination, and underwent a quantitative comput-erized tomography (pQCT) of the tibia. From pQCT images, we estimated markers of bone mass (BM), diaphyseal design (DD),and material quality (MQ). Mixed models were used to study the relationship between baseline tertiles of UTP with changes ofthe bone characteristics over the follow-up.ResultsAt baseline, higher levels of UTP were positively correlated with markers of BM, DD, and MQ. Compared with lowertertile of UTP, participants in the intermediate and highest tertiles had higher cortical bone area, cortical mineral content, andcortical thickness. However, participants in the intermediate and highest UTP tertiles experienced accelerated deterioration ofthese same parameters over the follow-up compared with those in the lowest UTP tertile.ConclusionsDietary intake of polyphenols estimated by UTP and dietary questionnaire was associated with long-term acceler-ated deterioration of bone health. Our study does not support the recommendation of increasing polyphenol intake for osteopo-rosis prevention.