Positive Health Online

Abstract

GRENON and COLLEAGUES,  (1)Department of Surgery, University of California, San Francisco, San Francisco, Calif; Department of Surgery, Veterans Affairs Medical Center, San Francisco, Calif. Electronic address: marlene.grenon@ucsfmedctr.org conducted a study to evaluate the association between n-3 polyunsaturated fatty acid content of red blood cells and inflammatory biomarkers in patients with peripheral artery disease (PAD).

Background

The n-3 polyunsaturated fatty acids are dietary components derived from fish oil with beneficial cardiovascular effects that may relate in part to anti-inflammatory properties. Peripheral artery disease (PAD) is characterized by a marked pro-inflammatory state. We hypothesized that the n-3 polyunsaturated fatty acids content of red blood cells (omega-3 index) would be correlated with biomarkers of inflammation and vascular function in a PAD cohort.

Methodology

This was a cross-sectional study of subjects who presented to an outpatient vascular surgery clinic for evaluation of PAD. We used linear regression to evaluate the independent association between the omega-3 index, inflammatory biomarkers (C-reactive protein [CRP], intercellular adhesion molecule-1, interleukin-6, and tumor-necrosis-factor-α) and endothelial function (brachial artery flow mediated dilation).

Results

64 subjects (61 claudicants and three with critical limb ischemia) were recruited for the study. The mean CRP level was 5.0 ± 5.0 mg/L, and the mean omega-3 index was 5.0% ± 1.8%. In an unadjusted model, the omega-3 index was negatively associated with CRP (38% increase in CRP for one standard deviation decrease in the omega-3 index; P = .007), which remained significant after adjustment for age, body mass index, smoking, ankle-brachial index, and high-density lipoprotein (33%; P = .04). There was also evidence for independent associations between the omega-3 index and IL-6 (P = .001). There were no significant associations between the omega-3 index and vascular function tests.

Conclusion

In a cohort of patients with PAD, the omega-3 index was inversely associated with biomarkers of inflammation even after adjustment for covariates including the ankle-brachial index. Because patients with PAD have a high inflammatory burden, further studies should be conducted to determine if manipulation of omega-3 index via dietary changes or fish oil supplementation could improve inflammation and symptoms in these patients.

References

Grenon SM(1), Conte MS, Nosova E, Alley H, Chong K, Harris WS, Vittinghoff E, Owens CD. Association between n-3 polyunsaturated fatty acid content of red blood cells and inflammatory biomarkers in patients with peripheral artery disease.  J Vasc Surg. 58(5):1283-90. Nov 2013. doi: 10.1016/j.jvs.2013.05.024. Epub Jul 2 2013.