Effect of omega-3 fatty acids on systemic lupus erythematosus disease activity: A systematic review and meta-analysis

Objective: Omega-3 fatty acids may decrease systemic lupus erythematosus (SLE) disease activity, however randomized controlled trials (RCT) have been small with conflicting findings. We conducted a systematic review and meta-analysis to estimate the effect of omega-3 fatty acids on SLE disease activity in adults. Methods: A literature search was conducted from database inception to January 2020. RCTs of adults with SLE comparing omega-3 fatty acids supplementation to placebo or standard of care that evaluated SLE disease activity were included. Abstracts, full text reviews, data abstraction and statistical analysis were evaluated independently by two investigators. Study-specific standardized mean differences (SMD) were estimated and combined using random-effects model. Results: Five RCTs with 136 patients in the comparison groups and 138 in the treatment groups, were included. All the studies used <= 3 g of omega-3 fatty acids. The trial follow-up time ranged from 12 to 52 weeks. The mean age of the patients was 43 years and 80% or more were female. Omega-3 fatty acids reduced SLE activity [SMD -0.33 (95CI: -0.57, -0.09), low certainty evidence, moderate effect size]. Transforming the SMD to the SLE Disease Activity Index (SLEDAI) scale, omega-3 fatty acids reduced disease activity by 0.9 (95CI: -1.6, -0.3, I-2 = 0%) SLEDAI points compared to placebo. Conclusion: This meta-analysis suggests that omega-3 fatty acids could provide therapeutic benefit in addition to immunosuppressive regimens used for SLE.