Dietary strategies to combat arterial stiffness in cardiometabolic disease: a network meta-analysis

Cardiovascular diseases (CVD) and hypertension (HTN) are leading causes of global morbidity and mortality. Arterial stiffness, assessed via augmentation index (AIx) and pulse wave velocity (PWV), serves as an independent prognostic marker of vascular damage; however, the comparative efficacy of dietary interventions on these parameters remains poorly characterized. This network meta-analysis (NMA) aimed to compare and rank the efficacy of dietary interventions, including supplements, nutraceuticals, and dietary patterns, on AIx and PWV in individuals with CVD or HTN. PubMed, Scopus, Web of Science, and the Cochrane Library were systematically searched for eligible randomized controlled trials (RCTs) published up to January 2025. Two independent reviewers screened and extracted data following PRISMA-NMA guidelines. A total of 48 RCTs comprising 2719 participants and 31 dietary interventions were included. Study quality and certainty of evidence (CoE) were assessed using the Cochrane Risk of Bias tool and GRADE approach, respectively. A random-effects NMA within a frequentist framework estimated mean differences (MDs) with 95% confidence intervals (CIs). For PWV, grape seed extract (MD: -1.70; 95%CI: -3.36 to -0.04; CoE: Moderate) and vitamin B9 (MD: -1.46; 95%CI: -2.61 to -0.31; CoE: Moderate) reduced arterial stiffness versus placebo. No intervention reached significance for AIx, though alpha-linolenic acid, dietary nitrate, and wine extract showed the greatest numerical improvements. Sensitivity analyses yielded results consistent with the primary analyses, with no publication bias detected. The grape seed extract and folic acid show potential to reduce arterial stiffness. Future population-specific, dose-optimized RCTs are warranted to establish definitive therapeutic recommendations.