Systemic inflammation changes following fish oil supplementation

Introduction: Omega-3 fatty acids [n-3] have been used in previous studies to control inflammatory markers with equivocal findings. Methods: This study was conducted using a double-blind, permuted-block-randomized and placebo controlled experimental design. End-Stage-Renal Disease (ESRD) patients (N=31) were followed prospectively for 2-months while supplementing their diet with either six grams of n-3 or corn oil (placebo [n-6]). Results: Cox proportional-hazards regression model revealed no significant differences between the groups concerning age, months on dialysis, diabetes, ethnicity, and tobacco history. ANCOVA that controlled for the covariate of compliance revealed a significant difference in the inflammatory marker of TNF-alpha with higher posttest levels in the n-3 group (p=.025). Though clinical differences were evident, there were no significant differences in other inflammatory markers of IL-1beta (p=.816) and IL-6 (p=.584). Conclusions: Supplementing n-3 in the diet did not change the cardiovascular risk profile of patients with elevated inflammation. The protective effects that have occurred in other studies are primarily due to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) found in n-3, which has been linked to reduced cardiovascular morbidity and mortality. It has recently been discovered that inflammation plays a significant role in cardiovascular mortality with novel approaches needed for ESRD patients. Yet, inflammation was lowered in the control group (TNF-alpha) suggesting n-6 may help to lower systemic inflammation in a chronic disease population but not n-3.