Fish-oil fatty acid supplementation in active rheumatoid arthritis. A double-blinded, controlled, crossover study.

STUDY OBJECTIVE: to determine the efficacy of fish-oil dietary supplements in active rheumatoid arthritis and their effect on neutrophil leukotriene levels. DESIGN: nonrandomized, double-blinded, placebo-controlled, crossover trial with 14-week treatment periods and 4-week washout periods. SETTING: academic medical center, referral-based rheumatology clinic. PATIENTS: forty volunteers with active, definite, or classical rheumatoid arthritis. Five patients dropped out, and two were removed for noncompliance. INTERVENTIONS: treatment with nonsteroidal anti-inflammatory drugs, slow-acting antirheumatic drugs, and prednisone was continued. Twenty-one patients began with a daily dosage of 2.7 g of eicosapaentanic acid and 1.8 g of docosahexenoic acid given in 15 MAX-EPA capsules (R.P. Scherer, Clearwater, Florida), and 19 began with identical-appearing placebos. The background diet was unchanged. MEASUREMENTS AND MAIN RESULTS: the following results favored fish oil placebo after 14 weeks: mean time to onset of fatigue improved by 156 minutes (95% confidence interval, 1.2 to 311.0 minutes), and number of tender joints decreased by 3.5 (95% Cl, -6.0 to -1.0). Other clinical measures favored fish oil as well but did reach statistical significance. Neutrophil leukotriene B4 production was correlated with the decrease in number of tender joints (Spearman rank correlation r=0.53; p less than 0.05). There were no statistically significant differences in hemoglobin level, sedimentation rate, or presence of rheumatoid factor or in patient-reported adverse effects. An effect from the fish oil persisted beyond the 4-week washout period. CONCLUSIONS: fish-oil ingestion results in subjective alleviation of active rheumatoid arthritis and reduction in neutrophil leukotriene B4 production. Further studies are needed to elucidate mechanisms of action and optimal dose and duration of fish-oil supplementation.

Effects of manipulation of dietary fatty acids on clinical manifestations of rheumatoid arthritis.

The effects of manipulation of dietary fatty acids in patients with rheumatoid arthritis were investigated in a 12-week, prospective, double-blind, controlled study. 17 patients took an experimental diet high in polyunsaturated fat and low in saturated fat, with a daily supplement (1.8 g) of eicosapentaenoic acid. 20 patients took a control diet with a lower polyunsaturated to saturated fat ratio and a placebo supplement. Compliance was monitored by plasma lipid gas-chromatographic analysis, Ivy bleeding time, and diet diaries. Results favoured the experimental group at 12 weeks for morning stiffness and number of tender joints. On follow-up evaluation 1-2 months after stopping the diet, the experimental group had deteriorated significantly in patient and physician global evaluation of disease activity, pain assessment, and number of tender joints. The control group had improved in morning stiffness and number of tender joints on follow-up.