LONDON (Reuters Health) – Many patients with irritable bowel syndrome (IBS) have undiagnosed lactose intolerance. For this subgroup of patients, diet therapy markedly improves symptoms and is extremely cost- and time-saving, according to Dutch investigators.
In a study, reported in the August issue of the European Journal of Gastroenterology and Hepatology, Dr. Clarisse J. M. Bohmer, from the Academic Hospital Vrije Universiteit in Amsterdam, and Dr. Hans A. R. E. Tuynman, from the Medical Centre Alkmaar, assessed the benefits of a lactose-restricted diet in 70 patients with IBS.
Seventeen patients were diagnosed with lactose malabsorption on the basis of a positive lactose tolerance test, the authors state. After 6 weeks of a lactose-restricted diet, a significantly greater improvement in symptoms was noted in the lactose malabsorptive group than in the non-malabsorptive group (p < 0.001). The benefits of lactose restriction persisted for most malabsorptive patients at 5 years after starting the diet.
For lactose intolerant patients, the mean number of visits per patient per year decreased significantly from 2.4, in the 5 years before diagnosis, to 0.6 in the 5 years after diagnosis, the researchers note (p < 0.0001).
"In general, managing patients with abdominal complaints due to IBS has disappointing results," the investigators state. "It is therefore of clinical importance to select a subgroup of these patients, who have lactose malabsorption and can be treated successfully by diet," they note.
"Another benefit of accurately diagnosing lactose intolerance is the savings made in cost and time, because the number of visits to the outpatient clinic can be markedly reduced," the researchers point out.