随机对照试验方案，旨在测试中国心血管疾病高危成年人 6 个月核桃补充剂的可接受性和依从性。

Protocol for a randomized controlled trial to test the acceptability and adherence to 6-months of walnut supplementation in Chinese adults at high risk of cardiovascular disease.

机构信息

The George Institute for Global Health, Faculty of Medicine, University of New South Wales, Sydney, Australia.

The George Institute for Global Health at Peking University Health Science Center, Beijing, China.

出版信息

Nutr J. 2021 Jan 6;20(1):3. doi: 10.1186/s12937-020-00660-7.

DOI:10.1186/s12937-020-00660-7

PMID:33407490

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7789667/

Abstract

BACKGROUND

Consumption of nuts improves cardio-metabolic risk factors in clinical trials and relates to lower risk of cardiovascular disease (CVD) in prospective observational studies. However, there has not been an adequately powered randomized controlled trial to test if nuts supplementation actually reduces incident CVD. In order to establish the feasibility of such a trial, the current study aimed to assess the acceptability and adherence to long-term nut supplementation amongst individuals at high CVD risk in China.

METHODS

This protocol described a 6-month trial performed in Ningxia Province in China among participants with a history of CVD or older age (female ≥65 years, male ≥60 years) with multiple CVD risk factors. Participants were randomized to control (received non-edible gift), low dose walnut (30 g/d), or high dose walnut (60 g/d) groups in a 1:1:1 ratio. Walnuts were provided at no cost to participants and could be consumed according to personal preferences. Follow-up visits were scheduled at 2 weeks, 3 months and 6 months. The primary outcome was fasting plasma alpha linolenic acid (ALA) levels used as an indicator of walnut consumption. Secondary outcomes included self-reported walnut intake from the 24 h dietary recalls. The target sample size of 210 provided 90% statistical power with two-sided alpha of 0.05 to detect a mean difference of 0.12% (as percent of total fatty acid) in plasma ALA between randomized groups.

RESULTS

Two hundred and ten participants were recruited and randomized during October 2019. Mean age of participants was 65 years (SD = 7.3), 47% were females, and 94% had a history of CVD at baseline. Across the three study groups, participants had similar baseline demographic and clinical characteristics.

DISCUSSION

This trial will quantify acceptability and adherence to long-term walnut supplementation in a Chinese population at high risk of CVD. The findings will support the design of a future large trial to test the effect of walnut supplementation for CVD prevention.

TRIAL REGISTRATION

NCT04037943 Protocol version: v3.0 August 14 2019.

摘要

背景

临床试验表明，食用坚果可改善心血管代谢风险因素，前瞻性观察研究表明，食用坚果与降低心血管疾病（CVD）风险相关。然而，目前还没有足够大的随机对照试验来测试坚果补充剂是否确实能降低 CVD 的发病率。为了确定此类试验的可行性，本研究旨在评估中国 CVD 高危人群对长期坚果补充的可接受性和依从性。

方法

本方案描述了在中国宁夏进行的一项为期 6 个月的试验，参与者为有 CVD 病史或年龄较大（女性≥65 岁，男性≥60 岁）且存在多种 CVD 风险因素的人群。参与者按照 1:1:1 的比例随机分配至对照组（接受非食用礼品）、低剂量核桃组（30 g/d）或高剂量核桃组（60 g/d）。核桃免费提供给参与者，可根据个人喜好食用。随访时间安排在 2 周、3 个月和 6 个月。主要结局指标为空腹血浆α-亚麻酸（ALA）水平，作为核桃摄入量的指标。次要结局指标包括 24 小时膳食回忆中报告的核桃摄入量。目标样本量为 210 例，双侧α 值为 0.05，具有 90%的统计效力，可检测到随机分组间血浆 ALA 差异的平均值为 0.12%（占总脂肪酸的百分比）。