Effects of omega-3 supplementation on serum albumin, pre-albumin and the CRP/albumin ratio in hospitalized patients: a systematic review and meta-analysis

Context Low serum albumin and pre-albumin concentrations are associated with edema, infection, thrombosis, heart failure, and mortality. Objective This comprehensive systematic review and meta-analysis of clinical trials was conducted to summarize the available findings on the impact of omega-3 supplementation on albumin, pre-albumin, and the C-reactive protein/albumin ratio in hospitalized patients. Data sources PubMed, Web of Science, Scopus, and Google Scholar databases were searched from January 1990 to October 2021. Data Extraction Extracted data from 50 randomized controlled trials (RCTs) with a total number of 3196 participants were analyzed using the random-effects model. The dose-dependent effect was also evaluated. Data Analysis Oral omega-3 supplementation significantly increased serum albumin concentrations in patients with cancer (weighted mean difference [WMD]: 0.19; 95% CI: 0.05, 0.33, P= 0.006), patients on dialysis (WMD: 0.14; 95% CI: 0.01, 0.28, P= 0.042), and those with hypoalbuminemia (WMD: 0.38; 95% CI: 0.03, 0.72, P = 0.033); however, there was no significant effect among patients with gastrointestinal or hepatologic diseases. Moreover, each 1000 mg/day increase in oral omega-3 supplementation resulted in elevated serum albumin levels in cancer patients (WMD: 0.15; 95% CI: 0.07, 0.24, P < 0.001). In addition, a favorable effect of oral omega-3 supplementation on pre-albumin levels was observed among patients with cancer (WMD: 33.87; 95% CI: 12.34, 55.39, P = 0.002). A similar significant effect of parenteral omega-3 supplementation on pre-albumin concentrations was seen among those with gastrointestinal and hepatologic diseases as well (WMD: 23.30; 95% CI: 13.58, 33.03, P < 0.001). No significant effect of oral omega-3 supplementation on the CRP/albumin ratio was found. Conclusions Overall, omega-3 fatty acids supplementation resulted in a favorable change in serum albumin and pre-albumin concentrations in hospitalized patients. Systematic Review Registration PROSPERO registration no. CRD42021285704.