Data_Sheet_1_The relationship between dietary intake of ω-3 and ω-6 fatty acids and frailty risk in middle-aged and elderly individuals: a cross-sectional study from NHANES.PDF

BackgroundFrailty is a complex clinical syndrome characterized by a decline in the functioning of multiple body systems and reduced adaptability to external stressors. Dietary ω-3 fatty acids are considered beneficial dietary nutrients for preventing frailty due to their anti-inflammatory and immune-regulating properties. However, previous research has yielded conflicting results, and the association between ω-6 fatty acids, the ω-6: ω-3 ratio, and frailty remains unclear. This study aims to explore the relationship between these factors using the National Health and Nutrition Examination Survey (NHANES) database.
Materials and methodsSpecialized weighted complex survey design analysis software was employed to analyze data from the 2005–2014 NHANES, which included 12,315 participants. Multivariate logistic regression models and restricted cubic splines (RCS) were utilized to assess the relationship between omega intake and frailty risk in all participants. Additionally, a nomogram model for predicting frailty risk was developed based on risk factors. The reliability of the clinical model was determined by the area under the receiver operating characteristic (ROC) curve, calibration curves, and decision curve analysis (DCA).
ResultsIn dietary ω-3 intake, compared to the T1 group (≤1.175 g/d), the T3 group’s intake level (>2.050 g/d) was associated with approximately 17% reduction in frailty risk in model 3, after rigorous covariate adjustments (odds ratio (OR) = 0.83, 95% confidence interval (CI): (0.70, 0.99)). In dietary ω-6 intake, the T2 group’s intake level (>11.423, ≤19.160 g/d) was associated with a 14% reduction in frailty risk compared to the T1 group (≤11.423 g/d) (OR: 0.86, 95% CI: 0.75, 1.00, p = 0.044). RCS results indicated a non-linear association between ω-3 and ω-6 intake and frailty risk. Both ROC and DCA curves demonstrated the stability of the constructed model and the effectiveness of an omega-rich diet in reducing frailty risk. However, we did not find a significant association between the ω-6: ω-3 ratio and frailty.
ConclusionThis study provides support for the notion that a high intake of ω-3 and a moderate intake of ω-6 may contribute to reducing frailty risk in middle-aged and elderly individuals.

研究背景
衰弱（Frailty）是一种复杂的临床综合征，以多系统功能衰退及对外界应激源的适应能力下降为特征。膳食ω-3脂肪酸因其抗炎与免疫调节特性，被认为是预防衰弱的有益膳食营养素。然而，既往相关研究结果存在矛盾，且ω-6脂肪酸、ω-6与ω-3的摄入比值和衰弱之间的关联仍不明确。本研究利用美国国家健康与营养调查（National Health and Nutrition Examination Survey, NHANES）数据库，探讨上述因素间的关联。
材料与方法
本研究采用专用加权复杂调查设计分析软件，对2005-2014年美国国家健康与营养调查（NHANES）的数据进行分析，共纳入12315名参与者。通过多因素logistic回归模型与限制性立方样条（Restricted Cubic Spline, RCS），评估所有参与者的脂肪酸摄入水平与衰弱风险的关联。此外，本研究基于衰弱危险因素构建了预测衰弱风险的列线图模型。采用受试者工作特征（Receiver Operating Characteristic, ROC）曲线下面积、校准曲线及决策曲线分析（Decision Curve Analysis, DCA）评估该临床模型的可靠性。
研究结果
膳食ω-3脂肪酸摄入方面，经严格协变量调整后，模型3中摄入水平＞2.050g/d的T3组，相较摄入水平≤1.175g/d的T1组，衰弱风险降低约17%（比值比（Odds Ratio, OR）=0.83，95%置信区间（Confidence Interval, CI）：0.70~0.99）。膳食ω-6脂肪酸摄入方面，相较T1组（≤11.423g/d），摄入水平＞11.423g/d且≤19.160g/d的T2组衰弱风险降低14%（OR=0.86，95%CI：0.75~1.00，p=0.044）。限制性立方样条分析结果显示，ω-3与ω-6脂肪酸摄入与衰弱风险之间存在非线性关联。受试者工作特征曲线与决策曲线分析均证实，所构建的模型稳定性良好，且富含脂肪酸的膳食可有效降低衰弱风险。但本研究未发现ω-6与ω-3的摄入比值与衰弱存在显著关联。
研究结论
本研究支持以下观点：较高的ω-3脂肪酸摄入与适度的ω-6脂肪酸摄入，有助于降低中老年人群的衰弱风险。