Reduced Joint Pain after Short-term Duodenal Administration of Seal Oil in Patients with Inflammatory Bowel Disease: Comparison with Soy Oil

Abstract

Background: Rheumatic joint pain is a common extraintestinal complication of inflammatory bowel disease (IBD). Because the high ratio of n-6 to n-3 fatty acids (FAs) of the Western diet might promote rheumatic disorders, we wanted to compare the effects of short-term duodenal administration of n-3 rich seal oil and n-6 rich soy oil, on IBD-related joint pain. Methods: Nineteen patients with IBD-related joint pain were included, 9 had Crohn’s disease and 10 had ulcerative colitis. Ten ml of seal oil (n = 10) or soy oil (n = 9) was self-administered through a nasoduodenal feeding tube 3 times daily for 10 days. Results: Compared with soy oil treatment, seal oil significantly reduced the duration of morning stiffness (P = 0.024), number of tender joints (P = 0.035), intensity of pain (P = 0.025) and the doctor’s scoring of rheumatic disease activity (P = 0.025) at end of the 10 days’ treatment period. Analysing the effects as area under the curve (area between the curve and baseline, zero) for the entire period from start of treatment until 6 months’ post treatment, suggested a long-lasting beneficial effect on joint pain of seal oil administration, while soy oil tended (not significantly) to aggravate the condition. Consistently, the serum ratios of n-6 to n-3 FAs (P << 0.01) and arachidonic acid to eicosapentaenoic acid (P << 0.01) were reduced after treatment with seal oil. Conclusion: The results suggest distinctive differential prolonged effects on IBD-related joint pain of short-term duodenal administration of n-3 rich seal oil (significant improvement) and n-6 rich soy oil (tendency to exacerbation).