Iskandar et al1 have presented a series of patients who continued to have functional gastrointestinal symptoms through their inflammatory bowel disease (IBD) progress. Their study was carefully conducted and is accompanied by a detailed analytic editorial written by Drossman2 on how tricyclic antidepressants may be helpful to these patients. Of course, most of us who have a large patient population with IBD are familiar with a continuation of nagging symptoms when the disease is decreasing in activity. Certainly, we are all frustrated—patients and physicians—in attempting to limit the symptoms. The symptoms are often similar to those of irritable bowel syndrome (IBS), as noted by Iskandar in his work.1 As such, it is not surprising that newer clinicians and a study group used tricyclic drugs to decrease their symptoms.
It is surprising to date that others have not used other popular treatments for IBS-type disease, particularly with the recent awareness that FODMAPs are ubiquitous and well known to affect many of the foods of our society, particularly of our children.3,4 All of these immunologic disorders cause gastrointestinal symptoms, either minimal or severe, and can cloud the issues of IBD.4,5
Murray, working in Nottingham in the Spiller group, used magnetic resonance imaging (MRI) in decreasing the symptoms due to the dilation or distention caused by FODMAPs. Sixteen healthy subjects participated in a 4-way, single-blinded, randomized, crossover MRI study. They drank 500 mL of water containing 40 g of glucose, fructose, or inulin or a 1:1 mixture of 40 g of glucose and 40 g of fructose. MRI scans were performed hourly for 5 hours measuring the volume of gastric contents, small bowel water content, and colonic gas. Breath pH gas was also assessed. It would seem that judicious use of fructose in the small bowel and inulin in the colon could be helpful in selected patients, in addition to the wise use of other food substances when attempting to decrease symptoms. Making dieticians and clinicians aware of these simple facts can be clinically helpful.
The physical effect of FODMAPs was clearly demonstrated.6 If such evidence is available, it is surprising that the elimination of FODMAPs is not tried more often by clinical centers. It is difficult to do at times and requires the careful attention of a dietician and a very concerned clinician. The FODMAP group of foods includes fermentable oligosaccharides, which are readily available in dietary fiber diets, disaccharides, which include the lactose group of foods, monosaccharides, and polyols, which include fructans. Many IBS patients are tried on these elimination diets but only with some success.
In Australia, a group working with Dr Gibson and colleagues conducted a very careful study in which baseline data of 30 patients with IBS and of 8 healthy individuals as controls matched for diet and demographics were collected. Subjects were randomly assigned to groups that were given 21 days of either a diet low in FODMAPs or a typical Australian diet, followed by a 21-day washout before crossing over to the alternate diet. They used a varying symptom rating system with an analog scale. All stool samples were collected from days 17 to 21 and evaluated for frequency, weight, water content, and stool chart rating. Subjects with IBS had lower overall gastrointestinal symptom scores on a diet with FODMAPs compared with the Australian diet. When the subjects were on a diet low in FODMAPs, symptoms were minimal and were altered when compared with those of controls. All IBS subjects have greater satisfaction in stool consistency when on the FODMAP diet. FODMAP effectively reduced functional gastrointestinal symptoms in IBS.
Thus, we can ask, would a diet low in FODMAPs work in some IBD patients? If tricyclic antidepressants can work in controlled studies, why not a diet low in FODMAPs? Certainly, it is worth a trial to the concerned clinicians and patients. Decreasing symptomology and the frustrations of IBD is always helpful.
1. Iskandar H, Cassel B, Kanuri N, et al..Tricyclic antidepressants for management of residual symptoms in inflammatory bowel disease.J Clin Gastroenterol.2014;48:423–429.
2. Drossman DA.Treatment of residual irritable bowel disease symptoms with low dose tricyclic antidepressants: why not?J Clin Gastroenterol.2014;48:390–392.
3. Halpin SJ, Ford AC.Prevalence of symptoms meeting criteria for irritable bowel syndrome in inflammatory bowel disease: systemic review and meta-analysis.Am J Gastroenterol.2012;107:1474–1482.
4. Sampson HA.Update in food allergy.J Clin All and Clin Immunol.2004;113:805–819.
5. Halmos EP, Power VA, Shepheard SJ, et al..A diet low in FODMAPs reduces symptoms of irritable bowel syndrome.Gastroenterology.2014;146:67–75.
6. Murray K, Wilkinson-Smith V, Hoad C, et al..Differential effects of FODMAPs (fermentable oligo-, di-, mono-saccharides, and polyols) in small and large intestine contents in healthy subjects shown by MRI.Am J Gastroenterol.2014;109:110–119.