Inverse Association between the Omega-3 Index and Neutrophil-Lymphocyte Ratio: Pooled Results from Four...

Area of Science:

• Cardiovascular Health
• Nutritional Science
• Inflammation Research

Background:

• The omega-3 Index (O3I), reflecting erythrocyte EPA and DHA levels, is inversely associated with neutrophil-lymphocyte ratio (NLR) and red blood cell distribution width (RDW).
• Observational studies suggest a link between O3I, NLR, and RDW, indicating potential roles in inflammation and health outcomes.

Purpose of the Study:

• To evaluate the impact of omega-3 interventions (EPA+DHA) on O3I, NLR, and RDW in healthy adults.
• To test if changes in O3I (ΔO3I) influence changes in NLR and RDW.

Main Methods:

• Individual-level data from three randomized, placebo-controlled trials and one omega-3 supplementation trial with a washout period were analyzed (n=436).
• Linear mixed-effects models were used to assess the effects of EPA+DHA supplementation on O3I, NLR, and RDW.
• Statistical significance was determined using a threshold of p<0.05.

Main Results:

• EPA+DHA supplementation (1160 mg/d) significantly increased O3I (ΔO3I =3.28%, p<0.001) compared to the control group (ΔO3I=-0.62%, p<0.001).
• NLR decreased significantly with EPA+DHA treatment (ΔNLR=-0.15, p<0.001) versus control (ΔNLR=-0.02, p<0.05).
• RDW showed no significant change with EPA+DHA supplementation (p=0.62), unlike the control group where it increased (ΔRDW =0.09, p<0.01).
• ΔNLR was inversely correlated with ΔO3I (r=-0.07, p<0.05), but no association was found between ΔO3I and ΔRDW (r=0.003, p=0.37).

Conclusions:

• In healthy adults, EPA+DHA supplementation effectively increases O3I and reduces NLR.
• Changes in O3I demonstrated an inverse correlation with changes in NLR, but not RDW.
• Further research is warranted to explore the clinical implications of omega-3 supplementation on NLR and RDW for individuals at risk of morbidity and mortality.