Department of Nutritional Sciences, Penn State University, University Park, PA.
J Am Heart Assoc. 2013 Nov 19;2(6):e000513. doi: 10.1161/JAHA.113.000513.
The erythrocyte membrane content of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which constitutes the omega-3 index (O3I), predicts cardiovascular disease mortality. The amount of EPA+DHA needed to achieve a target O3I is poorly defined, as are the determinants of the O3I response to a change in EPA+DHA intake. The objective of this study was to develop a predictive model of the O3I response to EPA+DHA supplementation in healthy adults, specifically identifying factors that determine the response.
A randomized, placebo-controlled, double-blind, parallel-group study was conducted in 115 healthy men and women. One of 5 doses (0, 300, 600, 900, 1800 mg) of EPA+DHA was given daily as placebo or fish oil supplements for ≈5 months. The O3I was measured at baseline and at the end of the study. There were no significant differences in the clinical characteristics between the groups at baseline. The O3I increased in a dose-dependent manner (P<0.0001), with the dose of EPA+DHA alone accounting for 68% (quadratic, P<0.0001) of the variability in the O3I response. Dose adjusted per unit body weight (g/kg) accounted for 70% (linear, P<0.0001). Additional factors that improved prediction of treatment response were baseline O3I, age, sex, and physical activity. Collectively, these explained 78% of the response variability (P<0.0001).
Our findings validate the O3I as a biomarker of EPA+DHA consumption and identify additional factors, particularly body weight, that can be used to tailor EPA+DHA recommendations to achieve a target O3I.
红细胞膜中二十碳五烯酸（EPA）和二十二碳六烯酸（DHA）的含量构成了ω-3 指数（O3I），可预测心血管疾病死亡率。达到目标 O3I 所需的 EPA+DHA 量尚未确定，EPA+DHA 摄入量变化对 O3I 反应的决定因素也尚未确定。本研究的目的是建立一种预测健康成年人 EPA+DHA 补充后 O3I 反应的模型，特别是确定决定反应的因素。
一项随机、安慰剂对照、双盲、平行组研究在 115 名健康男性和女性中进行。每天给予 5 种剂量（0、300、600、900、1800mg）的 EPA+DHA 或安慰剂作为鱼油补充剂，持续约 5 个月。在基线和研究结束时测量 O3I。基线时各组的临床特征无显著差异。O3I 呈剂量依赖性增加（P<0.0001），EPA+DHA 单独剂量解释了 O3I 反应变异性的 68%（二次，P<0.0001）。按单位体重（g/kg）调整剂量解释了 70%（线性，P<0.0001）。改善治疗反应预测的其他因素是基线 O3I、年龄、性别和体力活动。这些因素共同解释了 78%的反应变异性（P<0.0001）。
我们的研究结果验证了 O3I 作为 EPA+DHA 消耗的生物标志物，并确定了其他因素，特别是体重，可以用于根据目标 O3I 调整 EPA+DHA 建议。
