Positive Health Online

Abstract

CLELAND and colleagues, Rheumatology Unit, Royal Adelaide Hospital, Adelaide, SA 5000, Australia, Lcleland@mail.rah.gov.au, introduce a biomarker for the compliance of patients with the advice to take fish oil for rheumatoid arthritis.

Background

Fish oil supplements have been shown to have beneficial effects in rheumatoid arthritis due to the n-3 polyunsaturated fatty acids contained in them. As with any other medical advice, some patients comply with taking the supplement and some don't. This study aimed to explore the utility of eicosapentaenoic acid (EPA) as a measure of n-3 polyunsaturated fatty intake.

Methodology

Patients in an outpatient or office practice were given standardized advice to increase their intake of n-3 polyunsaturated fatty acids including taking 20 ml daily of bottled fish oil. Every 3 months, blood samples were obtained and analyzed for plasma phospholipids. Their content of EPA was used as a marker for the ingestion of fish oil.

Results

A diverse response was seen, with about one third of patients reaching a substantial increase of EPA over 12 months. A third showed little change, and the remaining third achieved intermediate levels. Data obtained over time from individual patients showed that elevations of EPA to over 5% of plasma phospholipid fatty acids could be maintained over at least 3 years.

Conclusion

EPA appears to be a convenient biomarker for patient compliance with advice to supplement their diet with fish oil. It may prove a useful adjunct to intention to treat analyses in determining the effect of fish oil on arthritis and other chronic inflammatory diseases.

References

Cleland LG, Proudman SM, Hall C, Stamp LK, McWilliams L, Wylie N, Neumann M, Gibson RA, James MJ. A biomarker of n-3 compliance in patients taking fish oil for rheumatoid arthritis. Lipids 38 (4): 419-424, Apr 2004.