Effect of omega-three supplementation on serum urate and gout flares in people with gout; a pilot randomized trial

OBJECTIVES: To determine the effect of omega-three supplementation with fish oil on serum urate, weight and body mass index (BMI) in people with gout. METHODS: A pilot 6-month, randomized, open-label clinical trial was undertaken in people with gout with serum urate ≥ 0.36 mmol/l. Forty participants were randomized to receive 6.2 g omega-3 fish oil daily or no fish oil for 24 weeks. Blood was obtained monthly for serum urate and red cell EPA (20:5n-3) DHA (22:6n-3) were measured using a blood spot collection system. RESULTS: There was no statistically significant difference in the mean (SEM) decrease in serum urate between baseline and week 24 between randomized groups: fish oil − 0.021 (0.02) mmol/l versus control − 0.006 (0.02) mmol/l. There was no significant difference in change in weight or BMI between baseline and week 24 between randomized groups. There was a statistically significant correlation between red cell omega-three concentrations and the total number of flares per participant between week 12 and week 24; total omega-three r = − 0.75 (p ≤ 0.001), EPA r = − 0.75 (p ≤ 0.001) and DHA r = -0.76 (p ≤ 0.001). In the omega-three fish oil group four participants reported gastrointestinal adverse effects definitely or probably related to the omega-three supplementation. CONCLUSIONS: The lack of untoward effect of omega three fish oil supplementation on serum urate and BMI together with the relationship between higher omega-three concentrations and lower gout flares supports the development of further adequately powered clinical trials to determine the role of omega-three supplements as prophylaxis against gout flares in people starting urate lowering therapy. Clinical trial registration ACTRN12617000539336p Registered 13/04/2017.