Table 1_Inverse associations between dietary flavonoid and subclass intakes and frailty in U.S. adults.docx

ObjectivesDietary flavonoids, known for their antioxidant and anti-inflammatory properties, may play a role in frailty prevention, but comprehensive population-based studies are lacking. This study aimed to examine the associations between dietary flavonoid intakes and the prevalence of frailty in a nationally representative sample of U.S. adults, and to identify the predominant flavonoid subclasses contributing to these associations.
MethodsCross-sectional data from 12,152 adults aged ≥20 years participating in the National Health and Nutrition Examination Survey (NHANES) 2007–2010 and 2017–2018 were analyzed. Dietary flavonoid intake was assessed using two 24-h dietary recalls. Frailty was defined using a 49-item frailty index. Weighted multivariate logistic regression models and restricted cubic spline analyses were employed to investigate the relationships between flavonoid intakes and frailty prevalence. Weighted quantile sum (WQS) regression and quantile g-computation (qgcomp) models were used to assess the mixed effects of flavonoid subclasses.
ResultsHigher intakes of total flavonoids (OR:0.79, 95% CI:0.65–0.95), anthocyanidins (OR:0.71, 95% CI:0.58–0.88), flavanones (OR:0.74, 95% CI:0.59–0.92), flavones (OR:0.76, 95% CI:0.59–0.97), and flavonols (OR:0.67, 95% CI:0.56–0.81) were significantly associated with lower prevalence of frailty after adjusting for confounders. Non-linear inverse associations were observed for total flavonoids and flavonols. The WQS model revealed that the mixture of flavonoid subclasses was inversely associated with frailty odds (OR: 0.58, 95% CI: 0.48–0.71, p < 0.001), with flavones, flavonols, and anthocyanidins as the top contributors. The qgcomp model confirmed these findings but highlighted potential opposing effects among subclasses.
ConclusionThis comprehensive analysis provides evidence that higher dietary flavonoid intakes, particularly flavones, flavonols, and anthocyanidins, are associated with lower prevalence of frailty in U.S. adults. These findings suggest that flavonoid-rich diets may be a promising strategy for frailty prevention, warranting further investigation through prospective cohort studies and randomized controlled trials.

研究目的：已知膳食类黄酮（dietary flavonoids）具有抗氧化与抗炎特性，或可在衰弱预防中发挥作用，但目前尚缺乏基于人群的全面相关研究。本研究旨在分析美国成人全国代表性样本中，膳食类黄酮摄入量与衰弱患病率之间的关联，并明确对上述关联具有主要贡献的类黄酮亚类。
研究方法：本研究分析了2007-2010年及2017-2018年美国国家健康与营养检查调查（National Health and Nutrition Examination Survey, NHANES）中12152名年龄≥20岁成人的横断面数据。采用两次24小时膳食回顾法评估膳食类黄酮摄入量；以49项衰弱指数定义衰弱状态。通过加权多因素logistic回归模型与限制性立方样条分析，探究类黄酮摄入量与衰弱患病率的关联；采用加权分位数和（WQS）回归与分位数g计算（qgcomp）模型，评估各类黄酮亚类的混合效应。
研究结果：校正混杂因素后，总类黄酮（比值比[OR]=0.79，95%置信区间[CI]=0.65~0.95）、花青素类（OR=0.71，95%CI=0.58~0.88）、黄烷酮类（OR=0.74，95%CI=0.59~0.92）、黄酮类（OR=0.76，95%CI=0.59~0.97）及黄酮醇类（OR=0.67，95%CI=0.56~0.81）的较高摄入量均与较低的衰弱患病率显著相关。总类黄酮与黄酮醇类摄入量与衰弱患病率呈非线性负相关。WQS模型结果显示，类黄酮亚类的混合摄入与衰弱发生比值呈负相关（OR=0.58，95%CI=0.48~0.71，P<0.001），其中黄酮类、黄酮醇类及花青素类为主要贡献因子。qgcomp模型验证了上述结果，但同时指出部分亚类间可能存在拮抗效应。
研究结论：本项全面分析证实，美国成人较高的膳食类黄酮摄入量（尤其是黄酮类、黄酮醇类及花青素类）与较低的衰弱患病率显著相关。上述结果表明，富含类黄酮的膳食或可成为衰弱预防的有效策略，有待后续前瞻性队列研究与随机对照试验进一步验证。