Irritable Bowel Syndrome (part 2)

A terrific 12 page review of irritable bowel syndrome (IBS): AC Ford, BE Lacy, NJ Talley. NEJM 2017; 376: 2566-78. While yesterday’s post reviewed some of the updated diagnostic and pathophysiology information, today’s will focus on treatment.

The article’s Table 2 outlines the most frequent treatments, their efficacy, side effects, costs, and quality of evidence. I’ve tried to highlight the key points from table and discussion:

  1. Soluble fiber (eg. psyllium). Efficacy: effective -start at low doses. Quality of evidence: Moderate, Cost: $15-30 per month.
  2. Low-FODMAP diet. Efficacy: “May be effective, nutritionist guidance helpful.” While there have been studies showing this diet can be effective, two studies have shown that this diet is not significantly superior to conventional IBS diets (eg. “eating small, regular meals and avoiding insoluble fiber, fatty foods, and caffeine”).Quality of evidence: Very low.
  3. Gluten-free diet.  Efficacy: May be effective.  “No additive effect over that of a low-FODMAP diet in another small RCT.” Quality of evidence: Very low.
  4. Antispasmodic drugs (eg. dicyclomine).Efficacy: May be effective. Quality of evidence: Low, “No high-quality trials.” Cost: $50 per month.
  5. Peppermint oil. Efficacy: Effective, though few RCTs and no FDA-approved end points. Quality of evidence: Moderate. “No high-quality trials.”  Cost: $9-19 per month
  6. Lubiprostone. Efficacy: Effective, though “only a modest benefit over placebo, particularly for abdominal pain.” Quality of evidence: Moderate. Cost: ~$350 per month.
  7. Linaclotide.  Efficacy: Effective.. ” Quality of evidence: High. “No high-quality trials.”  Cost: ~$350 per month.
  8. Alosetron/5-HT3 receptor antagonists.  Efficacy: Effective. ” Quality of evidence: High. “No high-quality trials.”  Cost: ~$350-1100 per month. Alosetron may trigger ischemic colitis.
  9. Eluxadoline.  Efficacy: Effective, though “only a modest benefit over placebo for global symptoms and no benefit over placebo for abdominal pain.”  Quality of evidence: High. “No high-quality trials.”  Cost: ~$1100 per month. May trigger pancreatitis.
  10. Rifaximin. Efficacy: Effective. Quality of evidence: Moderate. “Modest benefit over placebo.”  “Relapse among patients who have a response is usual.” Cost: ~$1500 per month.
  11. Probiotics. Efficacy: May be effective.  Quality of evidence: Low. “Few high-quality trials and no FDA-approved end points.”  Cost: ~$20 per month.
  12. Tricyclic antidepressants. Efficacy: Effective. Quality of evidence: Moderate.  “Few high-quality trials and no FDA-approved end points.”   “A meta-analysis showed that tricyclic antidepressants were more effective than placebo in 11 randomized trials involving a total of 744 patients.” Cost: ~$5-10 per month.
  13. Psychological treatments. Efficacy: Effective. Quality of evidence: Low.  “Few high-quality trials and no FDA-approved end points.” “Their efficacy may be overestimated because of the lack of blinding.” There is also difficulty for many patients in finding an appropriate provider.  Cost: ??
  14. Placebo. In treatment trials, a placebo response is noted in 30-40%.
  15. Complementary/Alternative Therapies.  “Herbal therapies remain unclear.  STW5 (Iberogast) has been tested and “showed superiority over placebo.” Melatonin “has been reported to reduce abdominal pain in patients with IBS.”

The authors recommend judicious testing  “Any reassurance derived from colonoscopy to rule out organic disease in patients with IBS is short-lived.”

The authors outline their typical approach.  “Reassurance, explanation, and a positive diagnosis are essential steps in management. We recommend starting with dietary modification (slowly increasing soluble fiber if the patient has IBS with constipation or instituting a low-FODMAP diet temporarily  if the patient has IBS with diarrhea or the mixed subtype of IBS). We also recommend increased exercise and stress reduction.  A probiotic may be added, especially if bloating is prominent.  Pain may be ameliorated with an antispasmodic agent or a tricyclic antidepressant, diarrhea with loperamide or a bile acid sequestrant (eg. colestipol) and constipation with polyethylene glycol.” The other therapies may be used in those with persistent IBS symptoms.

My take: When a disease has this many treatments, usually this means that none of the treatments are all that great.

Related blog posts:

Chattahoochee River

Disclaimer: These blog posts are for educational purposes only. Specific dosing of medications (along with potential adverse effects) should be confirmed by prescribing physician.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.

In Case Someone Asks…Low FODMAP Maternal Diet May Help Colic

According to a very small study, maternal ingestion of a low FODMAP diet reduced crying in colicy babies who were breastfed.  This report was presented at the recent United European Gastroenterology meeting (P0609).  The study consisted of a single-blind, open-label study of 18 infants.  The key finding was reduced crying from 142 minutes to 90 minutes over the 2 week study period.

A summary of this report is available at gastroendonews.com (May 2016, pg 8).

My take: A bigger study is needed to ascertain whether this intervention is worthwhile.  Many kids get better during a 2 week period without treatment.

Which Diet is Best for Irritable Bowel Syndrome?

As noted in this blog previously, there has been increasing evidence that a low FODMAPs (fermentable oligo-, di-, monosaccharides and polyols) diet is an effective option for irritable bowel syndrome (IBS) in adults and children. Now, a study (L Bohn et al. Gastroenterol 2015; 149: 1399-1407) directly compares a low FODMAPs diet with an IBS diet in a multicenter, parallel, single-blind study of 75 patients (adults) with Rome III criteria for IBS.

The comparison IBS diet recommended regular meal patterns, avoidance of large meals, reduced intake of fat and reduced insoluble fibers, caffeine, and gas-producing foods, such as beans, cabbage and onions.  In addition, this diet recommended avoidance of spicy foods, coffee, alcohol, soft drinks, and sweeteners that end with “-ol.” This diet has been recommended by the British Dietetic Association and by the National Institute for Health and Care Excellence (NICE).  NICE Guidelines for IBS

Key findings:

  • 67 patients completed the study.  The severity of IBS symptoms improved in both groups (P<.0001) without a difference between the two groups
  • 19 (50%) of low FODMAPs had reductions in IBS severity scores of >50 compared with baseline and 17 patients (46%) in the ‘traditional’ IBS diet group had this degree of improvement.

My take: Diet changes often result in symptom improvement in IBS.  Both of these diets can be recommended in patients with IBS.

Atlanta Sky

Atlanta Sky

FODMAPS Advice From Harvard

A recent post from Harvard Health Publications offers a succinct explanation of a low FODMAPs diet for irritable bowel syndrome.

Here’s the link: Try a FODMAPs diet to manage irritable bowel syndrome

 

Related blog posts:

Low FODMAPs Diet in Pediatric Irritable Bowel

A low FODMAPs diet has been associated with clinical improvement in adults with irritable bowel syndrome and “gluten sensitivity” (see links below).  Now, there is more data that this diet can be effective in the pediatric population (Chumpitazi BP, et al. Aliment Pharm Ther DOI: 10.1111/apt.13286. Article first published online: 24 JUN 2015 -Thanks to KT Park for this reference).  In addition, this small study (n=33) tries to correlate changes in symptoms with changes in the gut microbiome. Interestingly, the dietary trials were only 48 hours.

From the methods: Following a 7-day baseline period, “we employed a randomised, double-blind, crossover study design. Subjects received either a low FODMAP or typical American childhood diet (TACD) for 48 h. After 48 h on the first assigned diet, they returned to their habitual diet for 5 days. Following this 5-day washout period, they were crossed over to the other intervention diet for 48 h.”

Here is the abstract and a link to the full text: Randomised clinical trial: gut microbiome biomarkers are associated with clinical response to a low FODMAP diet in children with the irritable bowel syndrome

Abstract:

Background

A low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet can ameliorate symptoms in adult irritable bowel syndrome (IBS) within 48 h.

Aim

To determine the efficacy of a low FODMAP diet in childhood IBS and whether gut microbial composition and/or metabolic capacity are associated with its efficacy.

Methods

In a double-blind, crossover trial, children with Rome III IBS completed a 1-week baseline period. They then were randomised to a low FODMAP diet or typical American childhood diet (TACD), followed by a 5-day washout period before crossing over to the other diet. GI symptoms were assessed with abdominal pain frequency being the primary outcome. Baseline gut microbial composition (16S rRNA sequencing) and metabolic capacity (PICRUSt) were determined. Metagenomic biomarker discovery (LEfSe) compared Responders (≥50% decrease in abdominal pain frequency on low FODMAP diet only) vs. Nonresponders (no improvement during either intervention).

Results

Thirty-three children completed the study. Less abdominal pain occurred during the low FODMAP diet vs. TACD [1.1 ± 0.2 (SEM) episodes/day vs. 1.7 ± 0.4, P < 0.05]. Compared to baseline (1.4 ± 0.2), children had fewer daily abdominal pain episodes during the low FODMAP diet (P < 0.01) but more episodes during the TACD (P < 0.01). Responders were enriched at baseline in taxa with known greater saccharolytic metabolic capacity (e.g. Bacteroides, Ruminococcaceae, Faecalibacterium prausnitzii) and three Kyoto Encyclopedia of Genes and Genomes orthologues, of which two relate to carbohydrate metabolism.

Conclusions

In childhood IBS, a low FODMAP diet decreases abdominal pain frequency. Gut microbiome biomarkers may be associated with low FODMAP diet efficacy.

Related blog posts:

Baseball Broadcast with a Sense of Humor

Baseball Broadcast with a Sense of Humor

Nutrition University -Part 1

While issues with nutrition are ubiquitous, among the three areas of expertise for pediatric gastroenterologists (gastroenterology, hepatology, and nutrition), it does seem that nutrition expertise receives the least interest overall.  One effort to work on this is Nutrition University (N2U) sponsored by NASPGHAN/NASPGHAN foundation.

This is the first year in which the program has been opened up to physicians who have been in practice for more than 10 years and I am looking forward to a great review. Prior to attending, the participants were asked to review previous N2U modules which are available at NASPGHAN website: 2012 N2U Course ( a good source for CME as well).

This year’s syllabus: 2015 N2U Syllabus & Presentations (posted with permission from course organizers).

Last night the meeting started off with some comments by Praveen Goday (Praveen’s training in Cincinnati overlapped with mine) who has spearheaded this effort; subsequently the faculty addressed previously submitted attendee questions.

Here’s a sampling:

Should we be recommending a low FODMAPs diet for IBS? Rob Shulman indicated that about ~70% of adults responded in one study and that a similar study in children at Baylor College of Medicine produced similar results.  However, the diet is difficult and help from a dietician/nutritionist is needed.  If there is not a response in 7-10 days, then it is likely to be ineffective.

What should be the first formula for Cow’s Milk allergy/intolerance in infancy? The recommendation for most infants (not the very sickest) was to start with a hydrolysate formula which should be effective in more than 90%.  It was suggested that amino acid based formulas be reserved for hospitalized infants and those who do not respond to hydrolysates.

What about fish oil enterally or parenterally? James Heubi(*) noted that a lot more data is needed but fish oil either enterally or parenterally may be beneficial.  Rob Shulman commented that recent work indicates that vitamin E may be an important reason why fish oil could be better than soy-based lipid emulsions.

How practical are blenderized diets for gastrostomy fed children? Catherine Karls noted that the general goal is to provide nutrients which mimic the commercial formulas but there are many important caveats for DIY (do-it-yourself formula).

  • An RD needs to supervise to assure all micronutrient needs are being met.  Using computer programs, this facilitates calculating dietary reference intakes (DRIs).
  • Many parents prefer as homebrews are perceived as more natural or holistic
  • Some children have better tolerance (eg. volume-sensitive, patients with retching)
  • Drawbacks: time commitment, additional costs (though may be cheaper for some), and concerns regarding food safety
  • Homebrews are not recommended for jejunostomy feeds (gastrostomy only) or for those with small-caliber feeding tubes (needs to be at least 14 Fr)
  • Don’t use without the assistance of an RD!

Which is better for NAFLD -low carb or low fat? Ann Scheimann stated that this question is misleading –it is a lot more complicated.  It depends on the carbs and it depends on the fat.  Fructose clearly worsens NAFLD but so does a diet high in animal fat.

What are the nutritional management recommendations for acute pancreatitis? Justine Turner indicated that too many centers continue to rely on parenteral nutrition.  Yet, guidelines recommend the use of enteral nutrition due to lower risk of poor outcomes (eg. infections when NPO and on parenteral nutrition). ‘Resting pancreas is not helpful.’ With acute pancreatitis, enzyme secretion is reduced.  Her approach is to start nasogastric (NG) feedings at about 24 hours after presentation, as long as hemodynamically stable.  She indicated that nasojejunal (NJ) feedings can be done if NG is not well-tolerated.  NJ feedings are effective at reducing enzyme secretion.  However, Praveen Goday stated that his practice was often starting with NJ feeds.  “Sometimes there is only one shot” before the ICU team starts HAL.  Both physicians indicated that polymeric formulas were probably acceptable; however, starting with semi-elemental or elemental feedings are often done, again as a practical matter to minimize the likelihood of reverting to parenteral nutrition.

What is the advice regarding children who need far less than typical calories for weight (eg. wheelchair-bound inactive child)? Generally all nutrients are being met if a child less than 10 years is receiving 4 cans of commercial formula. For children 10 and older, receiving 6 cans per day should ensure adequate nutrients.  For those who fall below this threshold, several options:

  • Reduced calorie formula (eg. Pediasure Sidekicks, Compleat Reduced) are approximately 0.6 cal/mL but have all the other nutrients
  • Supplementation: multivitamin, calcium, phosphorus, protein
  • Need to meet at least 80% of typical fluid needs, thus not much rationale for 2 cal/mL formulas. As a practical matter, if the child is urinating well, they are receiving enough fluids.

*I was fortunate to have Jim as an attending during my fellowship at Cincinnati. In fact, even before then, Jim interviewed me when I was considering Cincinnati for my pediatric residency.  He is a terrific person and amazing to work with.

Disclaimer: This blog entry has abbreviated/summarized this presentation. Though not intentional, some important material is likely to have been omitted; in addition, transcription errors are possible as well.

These blog posts are for educational purposes only. Specific dosing of medications/diets (along with potential adverse effects) should be confirmed by prescribing physician/nutritionist.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.

 

Looking More Closely at a Persistent Question

Virtually everyday, families that I care for are trying to ascertain the link between their GI symptoms and the foods in their diet.  Many authoritative recommendations on irritable bowel have concluded that “food allergies (symptoms caused by an immune response) are rarely the culprit in IBS patients. Most IBS patients with food-related symptoms have food sensitivities or intolerances, which are not caused by an immune response.” (From Univ Virginia Irritable Bowel Diet PDF)

Whether the process is a sensitivity or an immune-reaction, many patients are quite sensitive to certain foods and many have had improvement with a low FODMAPs diet.

A much closer look at this problem with confocal laser endomicroscopy (CLE), in a pilot study (Gastroenterol 2014; 147: 1012-20), has shown measurable changes within five minutes of a food challenge that takes place during an endoscopy.  In this study, the researchers examined 36 patients with IBS who had suspected food intolerance and 10 control patients with Barrett’s esophagus.  Then during an endoscopy, the researchers used provoking solutions of cow’s milk, wheat, yeast, or soy.  The subjects had CLE before and after the challenges. To enhance visualization of changes, subjects had fluorescein dye injected intravenously prior to examination of the duodenum.

Results

  • In 22 of 36 patients, the challenges were considered positive.  These patients had mucosal changes including increase in intraepithelial lymphocytes, followed by disruption of the villi tips/shedding of cells, then fluorescein leakage into the lumen.
  • None of the control patients exhibited these changes.
  • 19 of 22 patients with positive challenges had a >50% reduction, after 4-weeks, in symptom score with individualized diet based on inciting antigen.

Bottomline:

This provocative study indicates that subtle mucosal changes can occur in a number of IBS patients in a quick and direct response to food challenges.  Perhaps when we look closer with technologies like CLE we will find more answers as to why certain foods provoke symptoms in adults and children with IBS.

Related blog posts:

Also noted –web-based information on gastroparesis:

Mechanism for FODMAPs diet

According to a recent study (Gut doi:10.1136/gutjnl-2014-307264 -thanks to KT Park for reference), a low FODMAPs diet changes the microbiome which in turn may relate to improvements in patients with irritable bowel syndrome.

Abstract

Objective A low FODMAP (Fermentable Oligosaccharides, Disaccharides, Monosaccharides And Polyols) diet reduces symptoms of IBS, but reduction of potential prebiotic and fermentative effects might adversely affect the colonic microenvironment. The effects of a low FODMAP diet with a typical Australian diet on biomarkers of colonic health were compared in a single-blinded, randomised, cross-over trial.

Design Twenty-seven IBS and six healthy subjects were randomly allocated one of two 21-day provided diets, differing only in FODMAP content (mean (95% CI) low 3.05 (1.86 to 4.25) g/day vs Australian 23.7 (16.9 to 30.6) g/day), and then crossed over to the other diet with ≥21-day washout period. Faeces passed over a 5-day run-in on their habitual diet and from day 17 to day 21 of the interventional diets were pooled, and pH, short-chain fatty acid concentrations and bacterial abundance and diversity were assessed.

Results Faecal indices were similar in IBS and healthy subjects during habitual diets. The low FODMAP diet was associated with higher faecal pH (7.37 (7.23 to 7.51) vs 7.16 (7.02 to 7.30); p=0.001), similar short-chain fatty acid concentrations, greater microbial diversity and reduced total bacterial abundance (9.63 (9.53 to 9.73) vs 9.83 (9.72 to 9.93) log10 copies/g; p<0.001) compared with the Australian diet. To indicate direction of change, in comparison with the habitual diet the low FODMAP diet reduced total bacterial abundance and the typical Australian diet increased relative abundance for butyrate-producing Clostridium cluster XIVa (median ratio 6.62; p<0.001) and mucus-associated Akkermansia muciniphila (19.3; p<0.001), and reduced Ruminococcus torques.

Conclusions Diets differing in FODMAP content have marked effects on gut microbiota composition. The implications of long-term reduction of intake of FODMAPs require elucidation.

Related blog posts:

Low-FODMAPs with or without Gluten-Free Diet in IBS

In a small study with 60 patients with irritable bowel syndrome (DDW abstract 374), the response rate to a Low-FODMAPs/Normal gluten diet was as effective as a Low-FODMAPs/Gluten-free diet.  Both diets were more effective in reducing abdominal symptoms than a normal diet.  A summary of this abstract from Gastroenterology & Endoscopy News: Nixing Gluten Offers No Added Benefit To Low-FODMAPs Diet for IBS

According to Lin Chang, MD: “The beneficial effect of low FODMAPs does not appear to be predominantly due to gluten avoidance.”

Related blog post: An Unexpected Twist for “Gluten Sensitivity” | gutsandgrowth

 

Use of Gluten-Free Diet with Inflammatory Bowel Diseases

As noted in a previous blog (The Search for a Dietary Culprit in IBD | gutsandgrowth), alternative diets have been explored both for symptom improvement and in efforts to improve inflammation in individuals with inflammatory bowel diseases (IBD).  A new study from North Carolina indicates that nearly 20% of patients have tried a gluten-free diet (GFD) to help control clinical symptoms in IBD (Inflamm Bowel Dis 2014; 20: 1194-97).

While adoption of a GFD clearly is effective for celiac disease, it has become popular, along with a low FODMAPs diet, as an alternative treatment for irritable bowel syndrome (IBS)/and “non-celiac gluten sensitivity.”  Since IBS is a common comorbidity with IBD (see recent blog: New Biomarker for Crohn’s Disease (Plus Two ), it is not surprising that a GFD would be used by some with IBD.  In this study, the authors performed a cross-sectional study using a GFD questionnaire in 1647 IBD patients though a CCFA longitudinal internet-based cohort.

Results:

  • 19.1% had previously tried a GFD and 8.2% reported current use of GFD.
  • 65.6% described improvement while on a GFD.  Improved symptoms included fatigue, nausea, bloating, abdominal pain, and diarrhea.
  • 0.6% of patients reported a concurrent diagnosis of celiac disease (which is similar to overall celiac prevalence in U.S.)

Given the structure of this study, which is mainly an internet survey, there are many limitations in its interpretation.  Certainly, this study does not prove that a GFD is effective for IBD.  However, it is clear that a GFD is used frequently and may improve IBD/IBS symptoms.

Take-home message: Particularly in patients who have ongoing symptoms despite  mucosal healing, pursuing either a low FODMAPs diet or a GFD may be helpful.

Related blog posts:

Disclaimer: These blog posts are for educational purposes only. Specific dosing of medications (along with potential adverse effects), implementation of diets and specific medical management interventions should be confirmed by prescribing physician.  Application of the information in a particular situation remains the professional responsibility of the practitioner.