Turning Conventional Colonoscopy Positioning Upside Down

A recent article (The American Journal of Gastroenterology 110, 1576-1581 (November 2015) | doi:10.1038/ajg.2015.298) indicates that right-sided positioning rather than left-side down results in quicker and more comfortable colonoscopy.  While it is disconcerting to realize that I had been trained exactly opposite, if this technique works for me, it will be particularly helpful when patients undergo combination procedures since this means that the bed would not need to be rotated.  Thanks to Mike Hart for this reference.

Right Or Left in COLonoscopy (ROLCOL)? A Randomized Controlled Trial of Right- versus Left-Sided Starting Position in Colonoscopy

N Vergis, A K McGrath, C H Stoddart and Jonathan M Hoare

OBJECTIVES:

Colonoscopy is technically challenging and can cause discomfort for patients. We aimed to test whether right-sided starting position for colonoscopy would result in shorter procedure time and greater patient comfort when compared with conventional left-sided starting position.

METHODS:

We conducted a randomized controlled trial in which patients were randomized to begin in either the right- (RL) or conventional left-lateral (LL) position. One hundred and sixty-three adult patients undergoing scheduled colonoscopy were stratified by age, gender, body mass index, and experience of the endoscopist. Patients were then randomized 1:1 in permuted blocks. The primary outcome measure was time to cecal intubation and secondary outcome measures included patient comfort that was evaluated by visual analog comfort scale.

RESULTS:

Median time to reach the cecum was quicker when colonoscopy began with patients positioned RL rather than LL (P=0.0078). Moreover, patients found RL more comfortable than LL (P=0.02). Multiple linear regression confirmed starting position in colonoscopy as an independent determinant of time to reach the cecum (P=0.007). Women and those who had previously undergone abdominal surgery gained the greatest benefit from right-sided positioning (RL vs. LL: 498 vs. 824 s; P=0.03 and 498 vs. 797 s; P=0.006, respectively).

CONCLUSIONS:

Our study reveals that right-sided positioning at the start of colonoscopy results in more comfortable and quicker procedures. Of the factors identified by multiple linear regression to independently have an impact on time to reach the cecum, only starting position is modifiable. Right-sided starting position may therefore be of benefit in colonoscopy, in particular for women and patients who have previously undergone abdominal surgery.

PPIs Alter the Microbiome

A couple of comments –today’s blog (below) and yesterday’s blog both point out potential concerns with proton pump inhibitors (PPIs).  There is a danger that when publications emphasize the potential consequences of PPI use (including NPR’s recent piece on kidney disease and PPIs) that physicians and families will overlook the value of these medications.

With regard to the benefits of PPIs, there are a large number of studies supporting the effectiveness of PPIs for various GI conditions.  As a result, there is little being published on drug effectiveness at this time.  On a daily basis, these medications prevent a great deal of suffering, heal esophagitis, heal ulcers and contribute to improved health.  If one looks only at the negative side of the ledger, this could create harm.

My personal belief is that when PPIs are used, that it is important to consider both the advantages and the disadvantages.  If the benefits are unclear, this increases the necessity of evaluating the risks, especially in vulnerable populations.  In addition, when the benefits are unclear, determining the length of therapy and/or performing appropriate diagnostic workup becomes essential.

Also, for pediatric gastroenterologists reading this blog, it is important to realize that my blog’s following is tiny in comparison to the circulation of the Journal of Pediatrics and news organizations like NPR.  Therefore, we need to engage our pediatrician/family medicine colleagues to help make sure that PPIs are used effectively.  I am looking forward to the January 26 NASPGHAN webinar on this topic.

——–

The degree to which proton pump inhibitors (PPIs) affect the gut microbiome is unclear.  A recent study of 12 healthy volunteers (DE Freedberg et al. Gastroenterol 2015; 149: 883-85, Clearing Out My Desk | gutsandgrowth) indicated that this was not much; however, an even more recent study (F Imhann et al. Gut 2015 December 9 (Gut doi:10.1136/gutjnl-2015-310376))  suggests otherwise (abstract below) -their conclusion: “On a population level, the effects of PPI are more prominent than the effects of antibiotics or other commonly used drugs.”  

Link: Proton pump inhibitors affect the gut microbiome

Abstract

BACKGROUND AND AIMS: Proton pump inhibitors (PPIs) are among the top 10 most widely used drugs in the world. PPI use has been associated with an increased risk of enteric infections, most notably Clostridium difficile. The gut microbiome plays an important role in enteric infections, by resisting or promoting colonisation by pathogens. In this study, we investigated the influence of PPI use on the gut microbiome.

METHODS: The gut microbiome composition of 1815 individuals, spanning three cohorts, was assessed by tag sequencing of the 16S rRNA gene. The difference in microbiota composition in PPI users versus non-users was analysed separately in each cohort, followed by a meta-analysis.

RESULTS: 211 of the participants were using PPIs at the moment of stool sampling. PPI use is associated with a significant decrease in Shannon’s diversity and with changes in 20% of the bacterial taxa (false discovery rate <0.05). Multiple oral bacteria were over-represented in the faecal microbiome of PPI-users, including the genus Rothia (p=9.8×10(-38)). In PPI users we observed a significant increase in bacteria: genera Enterococcus, Streptococcus, Staphylococcus and the potentially pathogenic species Escherichia coli.

CONCLUSIONS: The differences between PPI users and non-users observed in this study are consistently associated with changes towards a less healthy gut microbiome. These differences are in line with known changes that predispose to C. difficile infections and can potentially explain the increased risk of enteric infections in PPI users. On a population level, the effects of PPI are more prominent than the effects of antibiotics or other commonly used drugs.

My take: It is likely that the effects on the microbiome are even more notable in infants/younger children; in neonates, the changes in the microbiome could increase the risk of serious diseases like necrotizing enterocolitis.

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Yosemite

Yosemite

Burden of GI Diseases in U.S.

A useful article (AF Peery et al. Gastroenterol 2015; 149: 1731-41) provides data on the huge impact that GI & Liver diseases have.

Here are some key findings:

Leading GI symptoms (Ambulatory visits) in 2010 (Table 1):

  • Abdominal pain 27.1 million
  • Diarrhea 5.6 million
  • Vomiting 5.5 million
  • Nausea 4.7 million
  • Bleeding 3.6 million

Most Common Diagnosis from Hospital Admissions in 2012 (Table 5):

  • GI hemorrhage 507,440 admissions
  • Cholelithiasis with cholecystitis 389,180 admissions
  • Acute pancreatitis 275,170 admissions
  • Intestinal obstruction 256,775 admissions
  • Appendicitis 248,080 admissions
  • Chronic liver disease/viral hepatitis 243,170 admissions

Causes of Death in U.S. in 2012 (Table 7):

  • Colorectal cancer 51,139
  • Pancreatic cancer 38,797
  • Liver/bile duct cancer 22,973
  • Cirrhosis 17,495
  • Alcoholic liver disease 17,419
Gastroenterology Cover

Gastroenterology Cover

Trying to Understand Gastroparesis

…all I know is that I know nothing. –Socrates

Perhaps Socrates was a gastroenterologist.  So much of what we think we know, we are finding out is poorly understood.  This applies to gallbladder dyskinesia, sphincter of Oddi dysfunction and now gastroparesis.

A recent study (PJ Pasricha et al. Gastroenterol 2015; 149: 1762-74, commentary 1666-68) and commentary show how little we understand about gastroparesis.

The study was a large prospective surgery of 262 adult patients with gastroparesis (either diabetic or idiopathic).

Key findings:

  • 28% had improvement in the gastroparesis cardinal symptom index (GCSI) at 48 weeks.  Beyond 48 weeks, there were no significant reductions through week 192.
  • Favorable characteristics: male gender, age 50 and older, initial infectious prodrome (18% of cohort), antidepressant usage, and 4-hour gastric retention greater than 20%.
  • Unfavorable characteristics: obesity, smoking, use of pain modulators, moderate to severe abdominal pain, severe reflux, and moderate to severe depression.

The commentary suggests that those with the higher GCSI improved, in part, because of a regression toward the mean bias.  Other important commentary:

  • “More severely delayed gastric emptying was associated with a greater likelihood of improvement”
  • “There was no differences in outcome between diabetic or idiopathic gastroparesis.”
  • Gastric emptying tests are not reliable:  “Pathophysiologic tests are useful in clinical practice if they are reproducible, explain the symptoms, guide therapeutic choices, and determine response to therapy and long-term prognosis.  Despite its popularity, the gastric emptying test scores low on most of these criteria.”
  • “A metaanalysis found no correlation between the change in gastric emptying rate and the symptom response during prokinetic therapy…A 5-year prospective follow-up study of …functional dyspepsia…found that more than 50% improved…with no relation to the presence of delayed gastric emptying.”
  • “Using the term gastroparesis also can lead to premature closure in our efforts to understand the pathophysiology of symptoms…can lead to botulinum injections into the pylorus or placement of gastric stimulators (formerly called gastric pacemakers) for gastroparesis, both of which have been shown to be nonefficacious in controlled trials.”

My take: It is unclear “when to consider gastric emptying testing and how to use it in patient management.”  For the pediatric population, gastroparesis is more likely to be associated with a prodromal infection which increases the likelihood of recovery.

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Banning Mills

Banning Mills

NEJM: Functional Dyspepsia

A recent NEJM had a concise review of functional dyspepsia (Talley NJ, Ford AC. NEJM 2015; 373: 1853-63).

With regard to functional dyspepsia in adults, the authors note that using the Rome III criteria, the global prevalence is between 5% and 11%.

While symptoms do not reliably distinguish organic and functional dyspepsia, they note that “with a relatively low rate of identification of organic disease, it is neither desirable nor realistic to perform this test [upper gastrointestinal endoscopy] in all patients with dyspepsia.”

Their review suggests several criteria to consider to help determine who needs endoscopy including age >55 yrs, GI bleeding, dysphagia, persistent vomiting, unintentional weight loss, family history of gastric or esophageal cancer, and iron-deficiency anemia.

With regard to workup, they suggest testing for H pylori non invasively with either breath testing or stool antigen testing.  The review covers treatment approaches including acid suppression (“effect is modest”), antidepressants (“tricyclic antidepressants…should be preferred over selective serotonin-reuptake inhibitors”), prokinetic agents, psychological treatments, and complementary approaches.  Figure 3 provides a helpful algorithm.

With regard to prognosis, “approximately 15 to 20% of people with functional dyspepsia have persistent symptoms and 50% have resolution of symptoms; in the remaining 30 to 35% of patients symptoms will fluctuate and meet the criteria for another functional gastrointestinal disorder.”

Briefly noted: “Acute Anxiety and Anxiety Disorders are Associated with Impaired Gastric Accommodation in Patients with Functional Dyspepsia” HG Ly et al. Clin Gastroenterol Hepatol 2015; 13: 1584-91.

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Sunrise in Sandy Springs

Sunrise in Sandy Springs

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

The Latest on Lynch Syndrome

Briefly Noted:

AGA Guidelines on Diagnosis and Management of Lynch Syndrome: JH Rubenstein et al. Gastroenterol 2015; 149: 777-82. Technical Review 783-813. Patient Guideline Summary 814-14.

MB Yurgelun et al. Gastroenterol 2015; 149: 604-13.  Multigene panel testing from 1260 individuals with clinical Lynch syndrome.  9% had Lynch syndrome mutations identified, 5.6% had other cancer predisposing genes (eg. BRCA1) identified, and 479 had variants of uncertain clinical significance.

Related blog post:

 

“Men Sometimes See Exactly What They Wish To See” and Gluten Sensitivity

For me, a recent study (AD Sabatino et al. Clin Gastroenterol Hepatol 2015; 13: 1604-12, editorial 1613-15) was particularly interesting.  While it had “positive results,” these findings were based almost entirely on the results of three patients.

In brief, this study examined 61 adults (w/o celiac disease) who believed that gluten induced intestinal and extraintestinal symptoms.  These individuals were randomized to receive either 4.375 g/day of gluten or rice starch via capsules.  This amount of gluten is equivalent to 1 sandwich or 2 slices of bread.

Findings:

  • Overall, intake of gluten significantly increased symptoms compared to placebo (P=.034), including bloating, pain, foggy mind, depression, and aphthous stomatitis.
  • Looking at a scatterplot (Figure 4), it is abundantly clear that all of these findings are driven by 3 patients.
  • “In the vast majority of patients the clinical weight of gluten-dependent symptoms was irrelevant in light of the comparable degree of symptoms experienced with placebo”
  • “Our study did not provide any progress in identifying possible biomarkers of NCGS [non-celiac gluten sensitivity]”

This type of study, with mixed conclusions, led the editorialists to quote Spock (from Star Trek):

“In critical moments, men sometimes see exactly what they wish to see.”

Then, the editorial provides a historical context of NCGS with a review of the relevant prior studies.  Other comments:

  • “These findings can be a Rorschach test of sorts, in which the viewer draws interpretations that are  based on his or her prior beliefs about NCGS.”
  • The authors note that both the gluten and the control arm likely had a significant nocebo effect (negative placebo effect),
  • “This trial, like its predecessors, seems only to contribute to the uncertainty about NCGS.”

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Yellowstone Canyon

Yellowstone Canyon

 

A 6-Year Study of Amitriptyline, Escitalopram, and Functional Dyspepsia

A recent theme on this blog has been the difficulty of studying inexpensive therapies.  The issue is that there are not strong incentives for pharmaceutical companies to invest in treatment trials when the potential for profits is meager.  Fortunately, there are other funding mechanisms.  A recent study (NJ Talley et al. Gastroenterol 2015; 149:340-9), sponsored by the NIH, still was challenging.  One of the reasons is that when medicines are already approved by the FDA that can be used off-label and this can undermine recruitment.

Due to difficulty with enrollment, the researchers of this current study expanded to a total of 8 sites (initially 5) and settled for 292 patients rather than their goal of 400.  After a baseline washout of 2- to 4-week with assessment, patients with Rome II criteria for functional dyspepsia (FD) were assigned in a randomized, double-blind trial to either placebo, amitriptyline 50 mg, or escitalopram 10 mg for 10 weeks.

Exclusion criteria:

  • History of depression and not using antidepressants.
  • Anxiety
  • Symptom resolution with antisecretory therapy (eg. proton pump inhibitors)
  • History of esophagitis, ulcers, or organic gastrointestinal disease
  • Major physical illness
  • Drug/alcohol abuse
  • Nonsteroidal anti-inflammatory drugs

Inclusion criteria:

  • Required: previous normal EGD within 5 years
  • 18-75 years

Key terms:

  • “ulcer-like dyspepsia” pain centered in the upper abdomen is the predominant symptom
  • “dysmotility-like dyspepsia” non pain symptom predominates: fullness, bloating, early satiety, and nausea

Key Findings:

  • Adequate relief was noted in 40% of placebo-treated, 53% of amitriptyline-treated, and 38% of escitalopram-treated patients
  • Ulcer-like FD given amitriptyline were >3-fold more likely to report adequate relief compared with placebo for odds ratio of 3.1
  • Delayed gastric emptying was associated with being less likely to report adequate relief with an odds ratio of 0.4
  • Safety: while adverse effects were common, “there was no overall difference between the 3 arms (except in neurologic symptoms, with highest rates in the escitalopram arm) suggesting that…TCAs will be generally well tolerated at low doses.”

The associated editorial (pages 270-2) notes that the overall benefits of amitriptyline were modest.  They also reviewed the NORIG study (JAMA 2013; 310: 2640-9) which examined nortriptyline and placebo for idiopathic gastroparesis (n=130).  Similar to this study from Talley et al, the NORIG study found a lack of response to tricyclic antidepressants in this cohort with delayed gastric emptying and dysmotility; “the lack of efficacy in patients with dyspepsia with delayed gastric emptying suggests the possible utility of scintigrahic testing to select patients” for amitriptyline therapy.

Bottomline: This well-designed study supports the use of amitriptyline, but not escitalopram for the use of FD, mainly in those with pain-predominant symptoms.

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Mt Washburn, Yellowstone

Mt Washburn, Yellowstone