Intake of ω-3 polyunsaturated fatty acids in patients with rheumatoid arthritis: A systematic review and meta-analysis

Abstract

Rheumatoid arthritis (RA) is a chronic, autoimmune inflammatory disease of multiple joints that puts the patient at high risk for developing cardiovascular diseases (CVDs). The aim of the present study was to conduct an up-to-date systematic review and meta-analysis of published randomized controlled trials (RCTs) to assess potential changes in RA disease activity, inflammation, and CVD risk after oral intake of ω-3 polyunsaturated fatty acids. Publications up to July 31, 2016 were examined using the PubMed, SCOPUS, and EMBASE databases. English language; human subjects; both sexes; RCTs; oral intake of ω-3 fatty acids; minimum duration of 3mo; and no medication change throughout intervention. The Cochrane Risk of Bias tool was used to assess quality of trials. We included 20 RCTs, involving 717 patients with RA in the intervention group and 535 RA patients in the control group. Despite the evidence of overall low quality of trials, consumption of ω-3 fatty acids was found to significantly improve eight disease-activity-related markers. Regarding inflammation, only leukotriene B4 was reduced (five trials, standardized mean difference [SMD], -0.440; 95% confidence interval [CI], -0.676 to -0.205; I2=46.5%; P<0.001). A significant amelioration was found for blood triacylglycerol levels (three trials, SMD, -0.316; 95% CI, -0.561 to -0.070; I2=0.0%; P=0.012). The beneficial properties of ω-3 polyunsaturated fatty acids on RA disease activity confirm the results of previous meta-analyses. Among five proinflammatory markers evaluated, only leukotriene B4 was found to be reduced. However, a positive effect on blood lipid profile of patients with RA was evident, perhaps for the first time.