A case-control study on the diagnostic role of Omega-3 fatty acid levels in erythrocyte membranes of critically ill patients

Abstract

This study aimed to investigate the erythrocyte Omega-3 fatty acid index as a potential biomarker for clinical severity, nutritional status, and mortality risk in critically ill patients admitted to the intensive care unit (ICU). Using a case-control design, we evaluated 86 ICU patients with severe clinical conditions, including cardiovascular, respiratory, and oncological complications. Blood samples were analyzed to quantify eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) levels in erythrocyte membranes. Clinical outcomes were assessed at 28 and 60 days to determine correlations with fatty acid profiles. Our findings showed no significant differences in EPA, DHA, or combined Omega-3 index levels between survivors and non-survivors. Additionally, no meaningful correlations were found between Omega-3 indices and clinical severity scores (APACHE II, SOFA) or nutritional assessments. These results suggest that erythrocyte Omega-3 fatty acid levels may not be reliable prognostic markers of mortality or clinical trajectory in critically ill ICU patients. Although Omega-3 fatty acids play a role in inflammatory modulation, their membrane concentrations do not appear to reflect patient outcomes in this setting. Further research is warranted to explore alternative biomarkers or to incorporate broader inflammatory indices in critical care prognostication.