Effect of Fish Oil Supplements on Serum Paraoxonase Activity in Female Patients with Rheumatoid Arthritis: A Double-blind Randomized Controlled Trial

This study was conducted to determine the effect of fish oil (FO) supplements on high density lipoprotein cholesterol (HDL-C), apolipoprotein-AI (Apo-AI), malondialdehyde (MDA), arylesterase (Aryl), and paraoxonase-1 (PON1) activity in female patients with rheumatoid arthritis (RA). A total of 90 RA patients were randomly allocated into two groups that were treated with one FO pearl (1 gr) daily or placebo for three months in addition to conventional treatment. HDL-C, Apo-AI, and MDA levels as well as PON1 and Aryl activities were measured before and after treatment. Independent t-test was used to match basal parameters of case and control groups. Paired t-test was used to assess significance of the differences. Correlation was evaluated by Pearson’s test and the statistical significance was set at P < 0.05. No significant differences were noted between FO and placebo patients with regards to age, disease duration, post-menopausal status, conventional therapy, body mass index (BMI), and numbers of swollen and tender joints at the beginning of the study. There were 83 patients who completed the three-month follow up. Serum levels of HDL-C (P = 0.018), Apo-AI (P = 0.165), Aryl (P = 0.026), and PON1 (P = 0.049) activity increased, whereas MDA levels decreased significantly with FO supplementation (P = 0.077). Significant correlations between increased PON1 activity and both HDL-C (P = 0.007, r = 0.419) and Apo-AI (P < 0.001, r = 0.742) concentrations as well as between HDL-C and Apo AI levels (P = 0.01, r = 0.403) were found. According to the results of this study, FO could increase serum HDL-C and PON1 levels and Aryl activity in female patients with RA.