Fluid Restriction vs. Liberal Intake in Patients with Heart Failure: A Meta-Analysis of Randomized Trials

Abstract Background In the absence of enough supportive evidence, the US and European guidelines for the diagnosis and treatment of acute and chronic HF provide only general recommendations supporting fluid restriction (FR) for selected patients with symptomatic HF. We aimed to evaluate the risk of all-cause mortality, hospital readmissions and change in BNP, sodium and perceived thirst in HF patients with FR vs liberal fluid intake. Methods We performed a systematic literature search on PubMed, Embase, and Clinicaltrials.gov for relevant randomized controlled trials (RCTs) from inception until June, 2025. Risk ratios (RR), weighted mean differences (WMD) and 95% confidence intervals (CI) were pooled using a random-effects model with the Hartung–Knapp–Sidik–Jonkman (HKSJ) adjustment, and between-study variance (τ²) was estimated with restricted maximum likelihood (REML). Results A total of 9 RCTs with 1271 patients (614 in the FR group and 657 in the non-FR group; mean follow-up: 196.33 days) were included in the study. The mean age of patients among FR and non-FR groups was 69.48 and 68.67 years. Pooled analysis showed a statistically significant reduction in the risk of all-cause mortality with restricted fluid intake compared to liberal intake (RR = 0.54; 95% CI: 0.31–0.94; p = 0.03). There were no significant difference between restricted and liberal fluid intake groups (RR = 0.67;95% CI: 0.28 to 1.65; p = 0.31) regarding heart failure hospital readmissions. No significant differences were observed in perceived thirst (WMD = –6.89; 95% CI: –22.86 to 9.08; p = 0.26), serum BNP levels (WMD = 54.09 pg/mL; 95% CI: –316.86 to 425.04; p = 0.71), or sodium levels (WMD = 1.42 mmol/L; 95% CI: –0.68 to 3.51; p = 0.15). Conclusion Fluid restriction reduces the risk of all-cause mortality but not HF rehospitalizations in HF patients. Further studies are warranted to definitively confirm the present findings and result on the suitable changes in recommendations and clinical practice.