Highlights
- •The benefits of reducing salt intake in people with T2DM lack clear evidence.
- •This meta-analysis of RCTs suggests that sodium restriction significantly decreases SBP and DBP in patients with T2DM.
- •Our meta-analysis firstly provided direct evidence for sodium intake in patients with diabetes regardless of their BP status.
Abstract
Aims
Although current guidelines recommend reduction of salt intake in patients with diabetes,
the benefits of reducing salt intake in people with type 2 diabetes mellitus (T2DM)
lack clear evidence. Therefore, we performed a meta-analysis of available randomized
controlled trials (RCTs) of sodium restriction and blood pressure (BP) in patients
with T2DM.
Data synthesis
We performed a systematic search of the online databases that evaluated the effect
of dietary sodium restriction on BP in patients with T2DM. Sodium intake was expressed
by 24 h urinary sodium excretion (UNaV). Q statistics and I2 were used to explore between-study heterogeneity. A random-effects model was used
in the presence of significant heterogeneity; otherwise, a fixed-effects model was
applied. Eight RCTs with 10 trials (7 cross-over and 3 parallel designs) were included
in the meta-analysis. Compared with ordinary sodium intake, dietary sodium restriction
significantly decreased UNaV (weighted mean difference, WMD: −38.430 mmol/24 h; 95%
CI: −41.665 mmol/24 h to −35.194 mmol/24 h). Sodium restriction significantly lowered
systolic BP (WMD: −5.574 mm Hg; 95% CI: −8.314 to −2.834 mm Hg; I2 = 0.0%) and diastolic BP (WMD: −1.675 mm Hg; 95% CI: −3.199 to −0.150 mm Hg; I2 = 0.0%) with low heterogeneity among the studies. No publication bias was found from
Begg's and Egger's tests.
Conclusions
Sodium restriction significantly reduces SBP and DBP in patients with T2DM.
Keywords
Abbreviations:
BP (blood pressure), BRS (baroreflex sensitivity), CI (confidence interval), DBP (diastolic blood pressure), IGT (impaired glucose tolerance), SBP (systolic blood pressure), RCT (randomized controlled trial), SD (standard deviations), SE (standard error), T2DM (type 2 diabetes mellitus), UNaV (24 h urinary sodium excretion), WMD (weighted mean difference)To read this article in full you will need to make a payment
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Article info
Publication history
Published online: February 26, 2021
Accepted:
February 19,
2021
Received in revised form:
February 17,
2021
Received:
September 22,
2020
Handling Editor: P. StrazzulloIdentification
Copyright
© 2021 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.
