Department of Medicine, University of Otago, Dunedin, New Zealand.
Riddet Institute, Palmerston North, New Zealand.
BMC Med. 2022 Apr 22;20(1):139. doi: 10.1186/s12916-022-02328-x.
Higher dietary fibre intakes are associated with a reduced risk of developing cardiovascular disease (CVD), and increasing intake has been shown to reduce blood pressure and other cardiometabolic risk factors. The extent to which dietary fibre can further reduce risk for those with CVD and treated with cardioprotective drugs has not been clearly established. We have examined the evidence for dietary fibre as adjunct therapy in those with CVD or hypertension.
Ovid MEDLINE, Embase, PubMed, and CENTRAL were searched to June 2021. Prospective observational studies reporting on fibre intakes and mortality in those with pre-existing CVD and controlled trials of increasing fibre intakes on cardiometabolic risk factors in those with CVD or hypertension were eligible. Outcomes were mortality (studies) and cardiometabolic risk factors (trials). Data synthesis was with random effects and dose response. Certainty of evidence was assessed using GRADE.
Three prospective studies including 7469 adults with CVD, and 12 trials of 878 adults with CVD or hypertension were identified. Moderate certainty evidence indicates reduced all-cause mortality (relative risk, RR0.75 (95% confidence interval, CI 0.58-0.97)) when comparing higher with lower fibre intakes. Low certainty evidence from trials of adults with cardiovascular disease indicates increasing fibre intakes reduced total (mean difference, MD - 0.42 mmol/L (95%CI - 0.78 to - 0.05) and low-density lipoprotein (LDL) cholesterol (MD - 0.47mmol/L (95%CI - 0.85 to - 0.10)). High certainty evidence from trials of adults with hypertension indicates increasing fibre intakes reduces systolic (MD 4.3 mmHg (95% CI 2.2 to 5.8)) and diastolic blood pressure (MD 3.1 mmHg (95% CI 1.7 to 4.4)). Moderate and low certainty evidence indicated improvements in fasting blood glucose (MD 0.48 mmol/L (- 0.91 to - 0.05)) and LDL cholesterol (MD 0.29 mmol/L (95% CI 0.17 to 0.40)). Benefits were observed irrespective of cardioprotective drug use.
These findings emphasise the likely benefits of promoting greater dietary fibre intakes for patients with CVD and hypertension. Further trials and cohort analyses in this area would increase confidence in these results.
较高的膳食纤维摄入量与降低心血管疾病（CVD）发病风险相关，增加膳食纤维摄入量已被证明可降低血压和其他心血管代谢危险因素。膳食纤维在患有 CVD 并接受心脏保护药物治疗的人群中进一步降低风险的程度尚不清楚。我们研究了膳食纤维作为 CVD 或高血压患者辅助治疗的证据。
检索了 Ovid MEDLINE、Embase、PubMed 和 CENTRAL 数据库，检索时间截至 2021 年 6 月。纳入了报道 CVD 患者膳食纤维摄入量与死亡率的前瞻性观察性研究和 CVD 或高血压患者增加膳食纤维摄入量对心血管代谢危险因素影响的随机对照试验。研究结局为死亡率（观察性研究）和心血管代谢危险因素（随机对照试验）。采用随机效应模型和剂量反应分析进行数据合并。使用 GRADE 评估证据的确定性。
纳入了 3 项包括 7469 例 CVD 患者的前瞻性研究和 12 项纳入 878 例 CVD 或高血压患者的随机对照试验。较高膳食纤维摄入量与较低膳食纤维摄入量相比，可降低全因死亡率（相对风险，RR0.75（95%置信区间，CI0.58-0.97）），证据确定性为中等。来自 CVD 患者的随机对照试验的低确定性证据表明，增加膳食纤维摄入量可降低总胆固醇（平均差值，MD-0.42mmol/L（95%CI-0.78 至-0.05）和低密度脂蛋白胆固醇（MD-0.47mmol/L（95%CI-0.85 至-0.10））。来自高血压患者的随机对照试验的高确定性证据表明，增加膳食纤维摄入量可降低收缩压（MD4.3mmHg（95%CI2.2 至 5.8））和舒张压（MD3.1mmHg（95%CI1.7 至 4.4））。中等和低确定性证据表明，空腹血糖（MD0.48mmol/L（-0.91 至-0.05））和 LDL 胆固醇（MD0.29mmol/L（95%CI0.17 至 0.40））也有改善。无论是否使用心脏保护药物，均观察到获益。
这些发现强调了促进 CVD 和高血压患者增加膳食纤维摄入量的可能获益。在该领域进一步的试验和队列分析将提高对这些结果的信心。
