RESEARCH ARTICLE


Clinical Investigation: Determinants of Blood Cell Omega-3 Fatty Acid Content



Robert C. Blocka, *, William S. Harris b, James V. Pottala b
1 Division of Epidemiology, Department of Community and Preventive Medicine, University of Rochester School of Medicine and Dentistry, USA
2 Nutrition and Metabolic Disease Research Center, Sanford Research/USD, Sioux Falls, South Dakota, USA


© 2008 Block et al.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at the Division of Epidemiology, Department of Community and Preventive Medicine, University of Rochester School of Medicine and Dentistry, Box 644, 601 Elmwood Avenue, Rochester, New York 14642, USA; Tel: (585) 233-7265; Fax: (585) 461- 4532; E-mail: robert_block@urmc.rochester.edu


Abstract

Background:

Although red blood cell eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) content (the Omega-3 Index) predicts cardiovascular death, the factors determining the Index are unknown.

Methods:

In 704 outpatients, we undertook an investigation of the clinical determinants of the Index.

Results:

Factors associated with the Index in decreasing order were: EPA+DHA supplement use, fish consumption frequency, triglyceride level, age, high cholesterol history, and smoking. These factors explained 59% of Index variability, with capsules/fish intake together accounting for 47%. The Index increased by 13% (p< 0.0001) for each serving level increase in fish intake and EPA+DHA supplementation correlated with a 58% increase (p< 0.0001) regardless of background fish intake (p=0.25; test for interaction). A 100 mg/dL decrease in serum triglycerides was associated with a 15% higher (p<0.0001) Index.

Conclusions:

The intake of EPA+DHA-rich foods and supplements principally determined the Omega-3 Index, but explained only about half of the variability.