Effect Of Sodium Restriction Diet On Serum Electrolytes And Prognosis In Patients With Heart Failure: A Meta-analysis

Objective: To evaluate the effects of sodium restriction diet on serum electrolytes levels and prognosis in patients with heart failure by using Meta-analysis.Methods: Databases of Pub Med,Embase,Cochrane Library,CNKI,and Wan fang were searched for all relevant studies published from the date of database inception to January 2021.Randomized clinical trials that evaluated the efficacy of sodium restriction diet in patients with heart failure were enrolled in the study.The inclusion studies were divided into 3 groups according to the level of sodium restriction included low sodium diet(<2g/d),moderated sodium diet(2-3g/d)and normal diet(> 3g/d).The outcome included serum sodium,serum potassium,readmission,and all-cause mortality.The data were expressed as weight mean differences(WMD)or relative risk(RR)with 95% confidence interval(95% CI).Results: The study included 7 randomized controlled trials.In the pooled data analysis,the levels of serum sodium(WMD-7.40,95%CI-7.58 to-7.22,P<0.00001)and serum potassium(WMD-0.19,95%CI-0.29 to-0.09,P<0.0002)were decreased significantly in participants of low sodium diet group with heart failure.The differences on readmission(RR 4.00,95%CI 2.68 to5.97,P<0.00001)and all-cause mortality(RR 3.28,95%CI 1.78 to 6.05,P=0.0001)between low sodium group and moderate sodium group were statistically significant.However,no significant changes were observed in the normal sodium group compared with moderate sodium group on serum sodium(WMD 0,95%CI-1.05 to 1.05,P=1.00),serum potassium(WMD-0.10,95%CI-0.14 to 0.34,P=0.41)and all-cause mortality(RR 0.98,95%CI0.06 to 15.22,P=0.99).Conclusions: For patients with stable heart failure,low sodium diet will lead to abnormal electrolyte level compared with moderate sodium diet,and the risk of readmission and all-cause mortality is increased,which caused poor prognosis.There was no significant difference in serum sodium,potassium and all-cause mortality between moderate sodium restriction and normal sodium diet.