Correspondence

Enteric-Coated Fish Oil in Crohn's Disease

N Engl J Med 1996; 335:1397-1398October 31, 1996

Article

To the Editor:

The study by Belluzzi et al. (June 13 issue)1 suggests that fish oil reduced the frequency of relapse in patients with Crohn's disease. However, there is a serious flaw in the design of this study: the placebo group received a mixture of caprylic and capric acids. These saturated medium-chain fatty acids may not be an appropriate placebo. There is epidemiologic and experimental evidence that fatty acids, such as those contained in vegetable oils and fats, may have a role in the causation and pathogenesis of Crohn's disease.2,3 It is likely that the fatty acids given as placebo in this study were incorporated into the lipid membranes of enteric cells, thus affecting their permeability, cellular and humoral local defense mechanisms, and regenerative capacity. Is it not therefore possible that the placebo preparation contributed to and even triggered relapses rather than that the fish oil was beneficial?

Erik Guthy, M.D.
Klinikum Weiden, 92637 Weiden, Germany

3 References

1. 1

   Belluzzi A, Brignola C, Campieri M, Pera A, Boschi S, Miglioli M. Effect of enteric-coated fish-oil preparation on relapses in Crohn's disease. N Engl J Med 1996;334:1557-1560
   Full Text | Web of Science | Medline

2. 2

   Guthy E. Morbus Crohn und Nahrungsfette. Dtsch Med Wochenschr 1982;107:71-73
   CrossRef | Web of Science | Medline

3. 3

   Nagel E. Zur Bedeutung von Nahrungsfetten in der Pathogenese des M. Crohn Tierexperimentelle Studie am Schwein. Z Gastroenterol 1989;24:7-9
   

Author/Editor Response

The authors reply:

To the Editor: We think it very unlikely that the caprylic and capric acids given as placebo in our study increased the rate of relapse. We studied patients who were in clinical remission but at high risk for relapse,1 a fact that explains the high relapse rate at one year in the placebo group. Moreover, the relapse rate in our placebo group was similar to that of the placebo group in another study of similar patients in which the placebo was different.2 Although we do not know whether there were changes in the membranes of enteric cells, the administration of caprylic and capric acids did not alter the fatty-acid profile of red-cell membranes.

Andrea Belluzzi, M.D.
Stefano Boschi, B.S.
Corrado Brignola, M.D.
University of Bologna, 40138 Bologna, Italy

2 References

1. 1

   Brignola C, Iannone P, Belloli C, et al. Prediction of relapse in patients with Crohn's disease in remission: a simplified index using laboratory tests, enhanced by clinical characteristics. Eur J Gastroenterol Hepatol 1994;6:955-961
   CrossRef | Web of Science

2. 2

   Prantera C, Pallone F, Brunetti G, Cottone M, Miglioli M. Oral 5-aminosalicylic acid (Asacol) in the maintenance treatment of Crohn's disease. Gastroenterology 1992;103:363-368
   Web of Science | Medline