One Gene Mutation Identified for a Subset of People with Irritable Bowel Syndrome (IBS)

September 26, 2014

A September 5, 2014 news item from IFFGD reports that a gene mutation that appears to relate to irritable bowel syndrome has been identified in a genetic region known as SCN5A. SCN5A controls part of the function of the sodium channel, which is necessary for normal gastrointestinal motility.

This news item was based on a study of SCN5A in people with IBS that was published in Gastroenterology in June 2014. The authors included 29 researchers at the Mayo Clinic in Rochester, Minnesota and several other research centers in Sweden, Greece and Italy. The study involved genotype analysis of 584 people with IBS and 1380 people without IBS as controls. 2.2% of the people with IBS showed SCN5A encoding errors which disrupted sodium channel function. Interestingly, although diarrhea-predominant IBS was the most common subtype found in the study group with IBS, more of those found to have the SCN5A mutations were constipation-predominant rather than other IBS subtypes. Mexiletine, an anti-arrythmic drug used in restricted situations for certain cardiac conditions, resolved the disruption of the sodium channel when used on isolated cells in the laboratory. One person with IBS-C who was given mexiletine as a medication during the study also had a normal bowel pattern afterward. The overall findings of this study have been replicated 4 separate times with a total of 1745 people with IBS and unaffected control groups.The authors conclude that they have identified one mechanism of IBS and potential future treatment of it.

It should be emphasized that 2.2% is a very small subset of all people with IBS and this gene mutation is not necessarily the only potential factor leading to IBS symptoms, even in those who are eventually found to have it. At this time, it can only be identified in a research context, and cannot be tested or treated by physicians in a clinical setting. There is no single “IBS gene” that causes IBS in all people who develop it. Anecdotally, many people with IBS know that they have genetic relatives who also have IBS or commonly overlapping conditions, but many others with IBS have no known family history of the condition. There are many possible areas of continuing research into the causes of IBS. However, as with many advances over the past few years, this mutation in SCN5A is a promising partial answer and a potential source of hope for a small subset of people whose IBS cannot be adequately managed by currently available means.

 


When Irritable Bowel Syndrome (IBS) and Inflammatory Bowel Disease (IBD) Overlap or Coexist

September 19, 2014

Although inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) have similar acronyms and some similar symptoms, they are very different gastrointestinal disorders. The different forms of IBD, such as Crohn’s disease and ulcerative colitis, cause visible inflammation and other structural changes in the digestive tract, as well as tangible biomarkers in one’s blood that can be measured by existing tests. As such, IBD is traditionally classified by the medical profession as an “organic” disorder.  Meanwhile, IBS, in which no structural differences from a “normal” colon or biomarkers can be obviously seen through existing tests and procedures currently available to physicians in a clinical setting, is considered a “functional” disorder.

In addition, IBS is considerably more common than IBD. Some of the demographic groups that are at higher risk for each disorder are different. Treatments used for IBD generally do not work for and are not accepted medical protocol for IBS and vice versa. Anecdotally, community resources, such as support groups, tend to be more readily available for IBD than IBS. Some people may be diagnosed with both IBS and IBD, but one condition does not cause the other. In fact, one of the frequent challenges of both the IBS and IBD communities is making the media and general public– including sometimes our own IBS and/or IBD affected peers and families– aware that IBS and IBD are not different names for the same condition. Three years ago, this blog published a post about the differences. Irritable Bowel Syndrome (IBS) and Inflammatory Bowel Disease (IBD) Are Not the Same.

The basic differences outlined in that post and the associated linked resources are still valid, and as far as leading international researchers in gastroenterology currently understand the science, IBD and IBS are still separate disorders. But like much related to irritable bowel syndrome, the reality is much too complex to reduce to simple media sound bites or Internet memes. As mentioned in IBS Impact’s 2011 post on the subject, for some time, researchers had already recognized that some people with irritable bowel syndrome do have subtle inflammation, especially in the post infectious-IBS (IBS-PI) subset, and anti-inflammatories, including some medications traditionally prescribed for IBD, have been tested in clinical trials for IBS, before and since that post, with mixed results. Over many years, various academic researchers of functional gastrointestinal disorders like IBS have also found evidence of neurological changes in pain perception, dysfunction in neurotransmitters and the brain-gut axis, altered gut microflora, genetic changes, and changes in immune mediators, though at a lower level than in IBD, in various subsets of people with IBS. So although numerous pieces of the puzzle that is irritable bowel syndrome remain to be put together, it is increasingly clear that IBS is not just a disorder of function.

Conversely, IBD may not be as straightforward as traditionally assumed either, as is seen in the subset of people who have coexisting diagnoses of inflammatory bowel disease and irritable bowel syndrome. According to Douglas Drossman, MD, MACG, founder and co-director emeritus of the University of North Carolina Center for Functional GI and Motility Disorders,  founder and president of the Rome Foundation, and founder and president of the Drossman Center for the Education and Practice of Psychosocial Care, this group of people is now said by medical professionals to have what is called IBS-IBD. In his September 13, 2014 blog post, Understand IBS-IBD From the Biopsychosocial Perspective, Dr. Drossman writes that is now possible for IBD medications to resolve observable gastrointestinal inflammation to such microscopic levels that IBD is considered in remission. Yet, up to 20% of these people continue to experience significant pain and diarrhea similar to IBS-D. Interestingly, in  the past several years, researchers have observed that the way IBS-IBD presents is very similar to postinfectious IBS.

International experts in IBS like Dr. Drossman have long advocated a comprehensive biopsychosocial approach to treating IBS, in recognition of the influence psychological stress and cognitive beliefs can have on the physical aspects of IBS and vice versa. In the linked post, he explains its importance for the specific IBS-IBD subset as well.

The IBS-IBD subset of people with IBS is rarely, if ever, mentioned in educational material readily available to people with IBS, families and the media or general public.  IBS Impact thanks Dr. Drossman for his continuing leadership in the field and for bringing these aspects to wider attention through his post. It is hoped that in the future, further research in general and with the IBS-IBD group in particular will yield useful insights into the causes and treatment of both IBD and IBS.


Representative King of New York Co-Sponsors HR 842 for Functional Gastrointestinal and Motility Disorders

September 11, 2014

UPDATE: 06/13/2015: HR 842 did not pass, but a similar bill HR 2311 is currently in the House of Representatives for 2015-2016. Please click on the HR 2311 sub-category on the right sidebar of this blog to see the relevant posts.

According to THOMAS, the Library of Congress legislative database, and IFFGD/the Digestive Health Alliance, Representatives Peter T. (Pete) King (R-NY-2) has recently signed on as a co-sponsor to the Functional Gastrointestinal and Motility Disorders Research Enhancement Act of 2013.

Representative King is serving his eleventh term in Congress, currently representing the 2nd District of New York, which was recently re-districted and currently encompasses parts of both Nassau and Suffolk Counties in central and South Shore Long Island, including the Townships of Hempstead, Oyster Bay, Babylon and Islip and most of Fire Island. According to Representative King’s official House website, he is currently a member of the Subcommittee on Homeland Security and has a record of supporting legislation concerning the military, veterans and health care.  As previously discussed on this blog on August 12, 2011 and August 25, 2011, military service members and veterans are at disproportionately high risk of functional gastrointestinal disorders like IBS, which are already very common in the general population.

If you are a constituent of Representative King, please take a few minutes to write or call him with your thanks for his support of HR 842 and the functional gastrointestinal and motility disorders community.

In officially supporting HR 842, Representative King joins the lead sponsor, Representative F. James Sensenbrenner, Jr. (R-WI-5) and co-sponsors, Representative James Moran (D-VA-8), Representative Julia Brownley (D-CA-26), Representative Bobby Rush (D-IL-1),  Representative Gwen Moore (D-WI-5), Representative Ron Kind (D-WI-3), Representative Susan Davis (D-CA-53),  Representative Peter Welch (D-VT), Representative James McGovern (D-MA-2), Representative Gerald Connolly (D-VA-11), Representative Louise Slaughter (D-NY-25), Representative Bill Posey (R-FL-8), and Representative Ed Perlmutter (D-CO-7), Representative Jim Himes (D-CT-4), Representative André Carson (D-IN-7), and Representative Mo Brooks (R-AL-5), Representative Richard Neal (D-MA-1), Representative David Price (D-NC-4) and Carol Shea-Porter (D-NH-1)  U.S. citizens residing in the districts of Representative King’s  colleagues listed here, please thank them as well.

According to the information on THOMAS, it appears that the bill is currently under consideration in the Subcommittee on Health. Click on the link above if you would like to see a list of its members.

U. S. citizens, if your Member of Congress is not yet a co-sponsor of HR 842 and you have not contacted him or her recently to ask for his or her support, please see the previous post from March 2, 2013  for links to the bill and more details on how to do so.  Often, it takes multiple attempts to elicit any interest from legislators, so if you do not receive a reply, do not hesitate to try again or to switch contact methods until you attract attention. Keep in mind that your Representative may be different from before because of the 2012 elections, district boundaries that may have been re-drawn, or if you have moved.

Your personal experiences as a person with IBS and/or other functional GI/motility disorders, or as a concerned family member, friend or colleague, are most effective in communicating to legislators and their staff that there are real human beings behind the statistics. However, even general expressions of support are helpful.

HR 842 is bipartisan legislation (supported by members of both parties) and according to IFFGD discussions with IBS Impact,  is “revenue-neutral,” meaning that there will be no additional taxes or spending added to the current federal deficit if it is enacted. Discretionary funds are available at the National Institutes of Health to be allocated if Congress directs NIH, through this Act, that functional gastrointestinal and motility disorders are a priority. Congress will only do so if we, as a community, are able to show them the importance of the research, education and FDA coordination provided for in HR 842.

NIH grants funding to researchers throughout the world, not just in the U.S., so in the long run, enactment of this Act may also benefit readers with IBS in other countries. Medical research also sometimes involves multinational teams of scientists, and in any case, study results are usually published globally, adding to the cumulative knowledge worldwide.

It is IBS Impact’s understanding that HR 842 will not require a debate or vote on the floor of the House of Representatives, and will pass as soon as it reaches 218 sponsor/cosponsors, or a simple majority of the House. In order for this milestone to be accomplished during the current Congress, the 113th,  the necessary number of sponsor/cosponsors must be reached by December 2014. Every two years, the Congressional membership will be different as a result of elections. Thus, if HR 842 has not passed by that time,  a similar bill will have to be reintroduced and the FGIMD community will have to start the process of gathering co-sponsors anew. This is what occurred with HR 2239 in 2012. While it is quite common for legislation of various sorts to take several Congresses to pass, our continuing advocacy now can increase awareness, build momentum and perhaps accelerate passage. It is in our hands.

Check back on this blog or join IBS Impact’s Facebook page or Twitter feed for further updates on HR 842 as they occur. Links to the social media sites can be found on the right sidebar of the blog.


Clinical Trial: Probiotics and Fish Oil for IBS, University of Sheffield, UK, 2014

September 4, 2014

The Medical School at the University of Sheffield  in the United Kingdom is currently seeking 74 volunteers with IBS to take part in a clinical trial on how and why probiotics and fish oil may affect abdominal pain, bloating, anxiety and memory and overall function of the lower gastrointestinal tract.   Participants will take either a probiotic and fish oil or a placebo for 12 weeks, avoid other foods or supplements with high probiotic and/or fish oil content for the duration of the study, complete questionnaires and if willing, provide stool samples at two different times.  Total time commitment is up to 14 weeks and up to 4 brief in-person visits to the medical school. The study listing indicates that volunteers will receive compensation for their time, but the amount is not specified.

A detailed description in PDF format  of the study from the researchers can be found  here: ProFIBS 2014.This listing is summarized from an announcement on the IBS Network website and the above link. Any questions or concerns about the study should be communicated directly to the researchers by emailing profibs@sheffield.ac.uk or by telephoning  07437350047.

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While IBS Impact attempts to highlight a diversity of available opportunities, this is not intended as an exhaustive resource. Previous posts on open clinical trials for IBS can be found by clicking the clinical trials category in the blog archives on the upper right sidebar of this blog. We also have a page for IBS studies on the main IBS Impact site. Because studies stop accepting new volunteers or are completed over time, please check the post date on this blog, or the last update date on studies page, to verify that the study you are interested in is relatively recent rather than from a few years ago. Depending on how you accessed this blog, the post date will appear either at the top or at the bottom of the post, and is occasionally included in the post title. On the studies page on the main site, the date of the last update is at both the top and the bottom of the page. The research and links pages and the July 26, 2011 post provide additional general resources.

We welcome researchers affiliated with academic, medical or pharmaceutical entities, or reputable organizations representing IBS or related or commonly overlapping conditions, to contact us directly with additional studies they wish to be considered for posting or if an existing listing needs to be updated. Contact links for the founder/listowner and the webmaster can be found on the home page of the main IBS Impact website.

IBS Impact makes these study announcements available for general information, and encourages its members and site visitors to make their own individual, informed choices about their potential participation in any study. IBS Impact, as an entity, is not directly affiliated with any research sponsor and receives no funding from any source for studies or links we feature on this blog, the main site or social media.