Division of Cardiology, Department of Medicine, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, USA.
Cardiovascular Institute, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, USA.
Eur Heart J Cardiovasc Imaging. 2022 Nov 17;23(12):1690-1697. doi: 10.1093/ehjci/jeac031.
The ketogenic diet (KD) is standard-of-care to achieve myocardial glucose suppression (MGS) for assessing inflammation using fluorine-18 fluorodeoxyglucose-positron emission tomography (FDG-PET). As KD protocols remain highly variable between centres (including estimation of nutrient intake by dietary logs for adequacy of dietary preparation), we aimed to assess the predictive utility of nutrient intake in achieving MGS.
Nineteen healthy participants underwent short-term KD, with FDG-PET performed after 1 and 3 days of KD (goal carbohydrate intake <20 g/day). Nutrient consumption was estimated from dietary logs using nutrition research software. The area under receiver operating characteristics (AUROC) of macronutrients (carbohydrate, fat, and protein intake) for predicting MGS was analysed. The association between 133 nutrients and 4 biomarkers [beta-hydroxybutyrate (BHB), non-esterified fatty acids, insulin, and glucagon] with myocardial glucose uptake was assessed using mixed effects regression with false discovery rate (FDR) correction. Median (25th-75th percentile) age was 29 (25-34) years, 47% were women, and 42% were non-white. Median (25th-75th percentile) carbohydrate intake (g) was 18.7 (13.1-30.7), 16.9 (10.4-28.7), and 21.1 (16.6-29.0) on Days 1-3. No macronutrient intake (carbohydrate, fat, or protein) predicted MGS (c-statistic 0.45, 0.53, 0.47, respectively). Of 133 nutrients and 4 biomarkers, only BHB was associated with myocardial glucose uptake after FDR correction (corrected P-value 0.003).
During highly supervised, short-term KD, approximately half of patients meet strict carbohydrate goals. Yet, in healthy volunteers, dietary review does not provide reassurance for adequacy of myocardial preparation since no clear thresholds for carbohydrate or fat intake reliably predict MGS.
生酮饮食（KD）是实现心肌葡萄糖抑制（MGS）的标准治疗方法，用于使用氟-18 氟代脱氧葡萄糖正电子发射断层扫描（FDG-PET）评估炎症。由于 KD 方案在中心之间差异很大（包括通过饮食记录来估计营养素摄入量以评估饮食准备的充分性），我们旨在评估营养素摄入量在实现 MGS 方面的预测效用。
19 名健康参与者接受了短期 KD，在 KD 后 1 天和 3 天进行 FDG-PET（目标碳水化合物摄入量<20 g/天）。使用营养研究软件从饮食记录中估计营养素消耗。使用受试者工作特征曲线（ROC）分析宏量营养素（碳水化合物、脂肪和蛋白质摄入）预测 MGS 的曲线下面积（AUROC）。使用混合效应回归和错误发现率（FDR）校正评估 133 种营养素和 4 种生物标志物（β-羟丁酸（BHB）、非酯化脂肪酸、胰岛素和胰高血糖素）与心肌葡萄糖摄取的关系。中位数（25 至 75 百分位数）年龄为 29 岁（25 至 34 岁），47%为女性，42%为非白人。中位数（25 至 75 百分位数）碳水化合物摄入量（g）在第 1-3 天分别为 18.7（13.1-30.7）、16.9（10.4-28.7）和 21.1（16.6-29.0）。没有一种宏量营养素（碳水化合物、脂肪或蛋白质）摄入预测 MGS（c 统计量分别为 0.45、0.53 和 0.47）。在经过 FDR 校正后，133 种营养素和 4 种生物标志物中只有 BHB 与心肌葡萄糖摄取相关（校正后的 P 值为 0.003）。
在高度监督的短期 KD 期间，大约一半的患者达到严格的碳水化合物目标。然而，在健康志愿者中，饮食评估并不能保证心肌准备的充分性，因为没有明确的碳水化合物或脂肪摄入量阈值可以可靠地预测 MGS。
