1.
Does Sodium Intake Induce Systemic Inflammatory Response? A Systematic Review and Meta-Analysis of Randomized Studies in Humans.
Basdeki, ED, Kollias, A, Mitrou, P, Tsirimiagkou, C, Georgakis, MK, Chatzigeorgiou, A, Argyris, A, Karatzi, K, Manios, Y, Sfikakis, PP, et al
Nutrients. 2021;(8)
Abstract
Experimental studies suggest that sodium induced inflammation might be another missing link leading to atherosclerosis. To test the hypothesis that high daily sodium intake induces systemic inflammatory response in humans, we performed a systematic review according to PRISMA guidelines of randomized controlled trials (RCTs) that examined the effect of high versus low sodium dose (HSD vs. LSD), as defined per study, on plasma circulating inflammatory biomarkers. Eight RCTs that examined CRP, TNF-a and IL-6 were found. Meta-analysis testing the change of each biomarker in HSD versus LSD was possible for CRP (n = 5 studies), TNF-a (n = 4 studies) and IL-6 (n = 4 studies). The pooled difference (95% confidence intervals) per biomarker was for: CRP values of 0.1(-0.3, 0.4) mg/L; TNF-a -0.7(-5.0, 3.6) pg/mL; IL-6 -1.1(-3.3 to 1.1) pg/mL. Importantly, there was inconsistency between RCTs regarding major population characteristics and the applied methodology, including a very wide range of LSD (460 to 6740 mg/day) and HSD (2800 to 7452 mg/day). Although our results suggest that the different levels of daily sodium intake are not associated with significant changes in the level of systemic inflammation in humans, this outcome may result from methodological issues. Based on these identified methodological issues we propose that future RCTs should focus on young healthy participants to avoid confounding effects of comorbidities, should have three instead of two arms (very low, "normal" and high) of daily sodium intake with more than 100 participants per arm, whereas an intervention duration of 14 days is adequate.
2.
Current Data on Dietary Sodium, Arterial Structure and Function in Humans: A Systematic Review.
Tsirimiagkou, C, Basdeki, ED, Argyris, A, Manios, Y, Yannakoulia, M, Protogerou, AD, Karatzi, K
Nutrients. 2019;(1)
Abstract
BACKGROUND Subclinical arterial damage (SAD) (arteriosclerosis, arterial remodeling and atheromatosis) pre-exists decades before cardiovascular disease (CVD) onset. Worldwide, sodium (Na) intake is almost double international recommendations and has been linked with CVD and death, although in a J-shape manner. Studies regarding dietary Na and major types of SAD may provide pathophysiological insight into the association between Na and CVD. OBJECTIVES Systematic review of data derived from observational and interventional studies in humans, investigating the association between dietary Na with (i) atheromatosis (arterial plaques); (ii) arteriosclerosis (various biomarkers of arterial stiffness); (iii) arterial remodeling (intima-media thickening and arterial lumen diameters). DATA SOURCES Applying the PRISMA criteria, the PubMed and Scopus databases were used. RESULTS 36 studies were included: 27 examining arteriosclerosis, four arteriosclerosis and arterial remodeling, three arterial remodeling, and two arterial remodeling and atheromatosis. CONCLUSIONS (i) Although several studies exist, the evidence does not clearly support a clinically meaningful and direct (independent from blood pressure) effect of Na on arterial wall stiffening; (ii) data regarding the association of dietary Na with arterial remodeling are limited, mostly suggesting a positive trend between dietary Na and arterial hypertrophy but still inconclusive; (iii) as regards to atheromatosis, data are scarce and the available studies present high heterogeneity. Further state-of-the-art interventional studies must address the remaining controversies.