美国得克萨斯农工大学Bradley C Johnston团队比较了七种流行的结构化饮食方案和心血管风险增加患者的死亡率和重大心血管事件的风险。这一研究成果于2023年3月29日发表在《英国医学杂志》上。

为了确定结构化命名饮食和健康行为计划（饮食计划）在预防心血管疾病风险增加患者的死亡率和重大心血管事件方面的相对有效性，研究组在AMED（联合和补充医学数据库）、CENTRAL（科克伦控制试验中心注册中心）、Embase、Medline、CINAHL（护理和联合健康文献累积索引）和ClinicalTrials.gov等大型数据库中检索截至2021年9月的相关文献，对符合要求的随机对照试验进行系统综述和网络荟萃分析。

这些随机试验针对心血管疾病风险增加的患者，将饮食计划与最低干预措施（如健康饮食手册）或替代方案进行比较，这些方案至少有九个月的随访，并报告死亡率或重大心血管事件（如中风或非致命性心肌梗死）。除了饮食干预外，饮食计划还可以包括锻炼、行为支持和其他二级干预，如药物治疗。

主要结局包括全因死亡率、心血管死亡率和个体心血管事件（中风、非致命性心肌梗死和计划外心血管干预）。配对评审人员独立提取数据并评估偏倚风险。使用频率论方法和推荐、评价、开发和评估（GRADE）方法进行随机效应网络荟萃分析，以确定每个结果的证据确定性。

在7个命名的饮食计划（低脂，18项研究；地中海，12项；极低脂肪，6项；改性脂肪，4项；低脂低钠组合，3项；奥尼什，3项，普里蒂金，1项）中，对35548名参与者进行了40项符合条件的试验。

在最近报道的随访中，基于中等确定性证据，地中海饮食计划在预防全因死亡（优势比0.72；中等风险患者：五年内随访的风险差异为每1000人减少17人）、心血管死亡（0.55；每1000人少13人）、中风（0.65；每1000人减少7人）和非致命性心肌梗死（0.48；每1000年减少17人）方面优于最低干预预防。

根据中等确定性的证据，在预防全因死亡（0.84；每1000人中减少9人）和非致命性心肌梗死（0.77；每1000年减少7人）方面，低脂计划优于最低干预。对于高危患者来说，这两种饮食方案的绝对效果更为明显。地中海和低脂方案在死亡率或非致命性心肌梗死方面没有令人信服的差异。与通常基于低到中等确定性证据的最低干预相比，剩下的五个饮食计划通常几乎没有益处。

研究结果表明，适度确定的证据表明，促进地中海和低脂饮食的计划，无论是否进行体育活动或其他干预，都可以降低心血管风险增加患者的全因死亡率和非致命性心肌梗死风险。地中海项目也有可能降低中风风险。一般来说，其他命名的饮食计划并不优于最低限度的干预。

附：英文原文

Title: Comparison of seven popular structured dietary programmes and risk of mortality and major cardiovascular events in patients at increased cardiovascular risk: systematic review and network meta-analysis

Author: Giorgio Karam, Arnav Agarwal, Behnam Sadeghirad, Matthew Jalink, Christine L Hitchcock, Long Ge, Ruhi Kiflen, Waleed Ahmed, Adriana M Zea, Jovana Milenkovic, Matthew AJ Chedrawe, Montserrat Rabassa, Regina El Dib, Joshua Z Goldenberg, Gordon H Guyatt, Erin Boyce, Bradley C Johnston

Issue&Volume: 2023/03/29

Abstract:

Objective To determine the relative efficacy of structured named diet and health behaviour programmes (dietary programmes) for prevention of mortality and major cardiovascular events in patients at increased risk of cardiovascular disease.

Design Systematic review and network meta-analysis of randomised controlled trials.

Data sources AMED (Allied and Complementary Medicine Database), CENTRAL (Cochrane Central Register of Controlled Trials), Embase, Medline, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and ClinicalTrials.gov were searched up to September 2021.

Study selection Randomised trials of patients at increased risk of cardiovascular disease that compared dietary programmes with minimal intervention (eg, healthy diet brochure) or alternative programmes with at least nine months of follow-up and reporting on mortality or major cardiovascular events (such as stroke or non-fatal myocardial infarction). In addition to dietary intervention, dietary programmes could also include exercise, behavioural support, and other secondary interventions such as drug treatment.

Outcomes and measures All cause mortality, cardiovascular mortality, and individual cardiovascular events (stroke, non-fatal myocardial infarction, and unplanned cardiovascular interventions).

Review methods Pairs of reviewers independently extracted data and assessed risk of bias. A random effects network meta-analysis was performed using a frequentist approach and grading of recommendations assessment, development and evaluation (GRADE) methods to determine the certainty of evidence for each outcome.

Results 40 eligible trials were identified with 35548 participants across seven named dietary programmes (low fat, 18 studies; Mediterranean, 12; very low fat, 6; modified fat, 4; combined low fat and low sodium, 3; Ornish, 3; Pritikin, 1). At last reported follow-up, based on moderate certainty evidence, Mediterranean dietary programmes proved superior to minimal intervention for the prevention of all cause mortality (odds ratio 0.72, 95% confidence interval 0.56 to 0.92; patients at intermediate risk: risk difference 17 fewer per 1000 followed over five years), cardiovascular mortality (0.55, 0.39 to 0.78; 13 fewer per 1000), stroke (0.65, 0.46 to 0.93; 7 fewer per 1000), and non-fatal myocardial infarction (0.48, 0.36 to 0.65; 17 fewer per 1000). Based on moderate certainty evidence, low fat programmes proved superior to minimal intervention for prevention of all cause mortality (0.84, 0.74 to 0.95; 9 fewer per 1000) and non-fatal myocardial infarction (0.77, 0.61 to 0.96; 7 fewer per 1000). The absolute effects for both dietary programmes were more pronounced for patients at high risk. There were no convincing differences between Mediterranean and low fat programmes for mortality or non-fatal myocardial infarction. The five remaining dietary programmes generally had little or no benefit compared with minimal intervention typically based on low to moderate certainty evidence.

Conclusions Moderate certainty evidence shows that programmes promoting Mediterranean and low fat diets, with or without physical activity or other interventions, reduce all cause mortality and non-fatal myocardial infarction in patients with increased cardiovascular risk. Mediterranean programmes are also likely to reduce stroke risk. Generally, other named dietary programmes were not superior to minimal intervention.

DOI: 10.1136/bmj-2022-072003

Source: https://www.bmj.com/content/380/bmj-2022-072003