Effect of population-based sodium reduction interventions on blood pressure: a systematic review and meta-analysis of randomized trials.

Abstract

This systematic review and meta-analysis included cluster randomized controlled trials that compared population-based sodium reduction interventions with usual care for blood pressure (BP) management. We searched PubMed, Cochrane Central Register of Controlled Trials, and IchuShi-Web and utilized a random-effects meta-analysis of the weighted mean difference (MD) in the comparison groups to collect data from the included trials. The primary outcome includes the pooled MD of office BP from baseline to each follow-up period. This meta-analysis considered 36 articles with 66,803 participants to be eligible. The population-based sodium reduction interventions decreased office systolic BP (SBP) compared with usual care in 36 studies (MD: -2.64 mmHg [95% confidence interval: -3.48- to 1.80]), with evidence of heterogeneity. Office SBP exhibited significant benefits among in adults (30 studies) and adults/children (1 study) but not in children (5 studies). Furthermore, office diastolic BP demonstrated comparable benefits with office SBP. Sensitivity analyses by cluster type in adults revealed that the workplace-based intervention exerted a greater SBP-lowering effect than the clinic/facility-based intervention. However, no significant difference was observed in the SBP-lowering effect by intervention type. The interventions were more effective in hypertensive cohorts compared with non-hypertensive cohorts and in Asian cohorts compared with non-Asian cohorts. Additionally, the benefits for secondary outcomes, including salt (sodium chloride) intake, were similar to those for office BP. In conclusion, population-based sodium reduction interventions improved BP management compared with usual care. The benefits along with the observed heterogeneity should be considered prudent for implementation in public health and clinical practices. This meta-analysis considered 36 studies with 66,803 participants to be eligible. The population-based sodium reduction interventions decreased office BP compared with usual care in 36 studies, with evidence of heterogeneity. Sensitivity analyses by cluster type in adults (30 studies) revealed that community-, family-, school-, and workplace-based interventions reduced office SBP. Concerning intervention type, sodium reduction counseling, salt substitution, and monitoring decreased office SBP. Interventions were more effective in hypertensive cohorts compared with non-hypertensive cohorts. The benefits for salt intake (22 studies) and urinary sodium excretion (17 studies) were comparable to those for office BP. BP: blood pressure; DBP: diastolic blood pressure; MD: mean difference; Na: sodium; RR: risk ratio; SBP: systolic blood pressure.