Get Irritable Bowel Syndrome essential facts below. View Videos or join the Irritable Bowel Syndrome discussion. Add Irritable Bowel Syndrome to your PopFlock.com topic list for future reference or share this resource on social media.
Irritable Bowel Syndrome
functional bowel disorder characterized by chronic issues without an organic cause
About 10 to 15% of people in the developed world are believed to be affected by IBS. It is estimated that 45% of people globally are affected by IBS. It is more common in South America and less common in Southeast Asia. It is twice as common in women as men and typically occurs before age 45. The condition appears to become less common with age. IBS does not affect life expectancy or lead to other serious diseases. The first description of the condition was in 1820 while the current term "irritable bowel syndrome" came into use in 1944.
IBS can be classified as either diarrhea-predominant (IBS-D), constipation-predominant (IBS-C), or with alternating stool pattern (IBS-A) or pain-predominant. In some individuals, IBS may have an acute onset and develop after an infectious illness characterized by two or more of: fever, vomiting, diarrhea, or positive stool culture. This postinfective syndrome has consequently been termed "postinfectious IBS" (IBS-PI).
The risk of developing IBS increases six-fold after acute gastrointestinal infection. Postinfection, further risk factors are young age, prolonged fever, anxiety, and depression. Psychological factors, such as depression or anxiety, have not been shown to cause or influence the onset of IBS, but may play a role in the persistence and perceived severity of symptoms. Nevertheless, they may worsen IBS symptoms and quality of life. Antibiotic use also appears to increase the risk of developing IBS. Research has found that genetic defects in innate immunity and epithelial homeostasis increase the risk of developing both post-infectious as well as other forms of IBS.
Publications suggesting the role of the brain-gut axis appeared in the 1990s and childhood physical and psychological abuse is often associated with the development of IBS. It is believed that psychological stress may trigger IBS in predisposed individuals.
Given the high levels of anxiety experienced by people with IBS and the overlap with conditions such as fibromyalgia and chronic fatigue syndrome, a potential explanation for IBS involves a disruption of the stress system. The stress response in the body involves the hypothalamic-pituitary-adrenal axis (HPA) and the sympathetic nervous system, both of which have been shown to operate abnormally in people with IBS. Psychiatric illness or anxiety precedes IBS symptoms in two-thirds of people with IBS, and psychological traits predispose previously healthy people to developing IBS after gastroenteritis.
Approximately 10 percent of IBS cases are triggered by an acute gastroenteritis infection. The CdtB toxin is produced by bacteria causing gastroenteritis and the host may develop an autoimmunity when host antibodies to CdtB cross-react with vinculin. Genetic defects relating to the innate immune system and epithelial barrier as well as high stress and anxiety levels appear to increase the risk of developing post-infectious IBS. Post-infectious IBS usually manifests itself as the diarrhea-predominant subtype. Evidence has demonstrated that the release of high levels of proinflammatory cytokines during acute enteric infection causes increased gut permeability leading to translocation of the commensal bacteria across the epithelial barrier; this in turn can result in significant damage to local tissues, which can develop into chronic gut abnormalities in sensitive individuals. However, increased gut permeability is strongly associated with IBS regardless of whether IBS was initiated by an infection or not. A link between small intestinal bacterial overgrowth and tropical sprue has been proposed to be involved as a cause of post-infectious IBS.
Small intestinal bacterial overgrowth (SIBO) occurs with greater frequency in people who have been diagnosed with IBS compared to healthy controls. SIBO is most common in diarrhea-predominate IBS but also occurs in constipation-predominant IBS more frequently than healthy controls. Symptoms of SIBO include bloating, abdominal pain, diarrhea or constipation among others. IBS may be the result of the immune system interacting abnormally with gut microbiota resulting in an abnormal cytokine signalling profile.
Certain bacteria are found in lower or higher abundance when compared with healthy individuals. Generally Bacteroidetes, Firmicutes, and Proteobacteria are increased and Actinobacteria, Bifidobacteria, and Lactobacillus are decreased. Within the human gut, there are common phyla found. The most common is Firmicutes. This includes Lactobacillus, which is found to have a decrease in people with IBS, and Streptococcus, which is shown to have an increase in abundance. Within this phylum, species in the class Clostridia are shown to have an increase, specifically Ruminococcus and Dorea. The family Lachnospiraceae presents an increase in IBS-D patients. The second most common phylum is Bacteroidetes. In people with IBS, the Bacteroidetes phylum has been shown to have an overall decrease, but an increase in the species Bacteroides. IBS-D shows a decrease for the phylum Actinobacteria and an increase in Proteobacteria, specifically in the family Enterobacteriaceae.
There is growing evidence that alterations of gut microbiota (dysbiosis) are associated with the intestinal manifestations of IBS, but also with the psychiatric morbidity that coexists in up to 80% of people with IBS. The role of the gut mycobiota, and especially of the abnormal proliferation of the yeast Candida albicans in some people with IBS, was under investigation as of 2005.
Prevalence of protozoal infections in industrialized countries (United States and Canada) in the 21st century
As of 2017, evidence indicates that blastocystis colonisation occurs more commonly in IBS affected individuals and is a possible risk factor for developing IBS.Dientamoeba fragilis has also been considered a possible organism to study, though it is also found in people without IBS.
Vitamin D deficiency is more common in individuals affected by irritable bowel syndrome. Vitamin D is involved in regulating triggers for IBS including the gut microbiome, inflammatory processes and immune responses, as well as psychosocial factors.
SCN5A mutations are found in a small number of people who have IBS, particularly the constipation-predominant variant (IBS-C). The resulting defect leads to disruption in bowel function, by affecting the Nav1.5 channel, in smooth muscle of the colon and pacemaker cells.
Genetic, environmental, and psychological factors seem to be important in the development of IBS. Studies have shown that IBS has a genetic component even though there is a predominant influence of environmental factors.
There is evidence that abnormalities occur in the gut flora of individuals who have IBS, such as reduced diversity, a decrease in bacteria belonging to the phylum Bacteroidetes, and an increase in those belonging to the phylum Firmicutes. The changes in gut flora are most profound in individuals who have diarrhoea predominant IBS. Antibodies against common components (namely flagellin) of the commensal gut flora are a common occurrence in IBS affected individuals.
Chronic low-grade inflammation commonly occurs in IBS affected individuals with abnormalities found including increased enterochromaffin cells, intraepithelial lymphocytes, and mast cells resulting in chronic immune-mediated inflammation of the gut mucosa. IBS has been reported in greater quantities in multigenerational families with IBS than in the regular population. It is believed that psychological stress can induce increased inflammation and thereby cause IBS to develop in predisposed individuals.
No specific laboratory or imaging tests can diagnose irritable bowel syndrome. Diagnosis should be based on symptoms, the exclusion of worrisome features, and the performance of specific investigations to rule out organic diseases that may present similar symptoms.
The Rome IV criteria includes recurrent abdominal pain, on average, at least 1 day/week in the last 3 months, associated with two or more of the following criteria:
Related to defecation
Associated with a change in frequency of stool
Associated with a change in form (appearance) of stool.
Physicians may choose to use one of these guidelines or may simply choose to rely on their own anecdotal experience with past patients. The algorithm may include additional tests to guard against misdiagnosis of other diseases as IBS. Such "red flag" symptoms may include weight loss, gastrointestinal bleeding, anemia, or nocturnal symptoms. However, red flag conditions may not always contribute to accuracy in diagnosis; for instance, as many as 31% of people with IBS have blood in their stool, many possibly from hemorrhoidal bleeding.
The diagnostic algorithm identifies a name that can be applied to the person's condition based on the combination of symptoms of diarrhea, abdominal pain, and constipation. For example, the statement "50% of returning travelers had developed functional diarrhea while 25% had developed IBS" would mean half the travelers had diarrhea while a quarter had diarrhea with abdominal pain. While some researchers believe this categorization system will help physicians understand IBS, others have questioned the value of the system and suggested all people with IBS have the same underlying disease but with different symptoms.
Ruling out parasitic infections, lactose intolerance, small intestinal bacterial overgrowth, and coeliac disease is recommended before a diagnosis of irritable bowel syndrome is made. An upper endoscopy with small bowelbiopsies is necessary to identify the presence of celiac disease.. An ileocolonoscopy with biopsies is useful to exclude Crohn's disease.
Chronic use of certain sedative-hypnotic drugs, especially the benzodiazepines, may cause irritable bowel-like symptoms that can lead to a misdiagnosis of irritable bowel syndrome.
Several medical conditions, or comorbidities, appear with greater frequency in people with IBS.
Neurological/psychiatric: A study of 97,593 individuals with IBS identified comorbidities such as headache, fibromyalgia, and depression. IBS occurs in 51% of people with chronic fatigue syndrome and 49% of people with fibromyalgia, and psychiatric disorders occur in 94% of people with IBS.
Inflammatory bowel disease: IBS may be a type of low-grade inflammatory bowel disease. Researchers have suggested IBS and IBD are interrelated diseases, noting that people with IBD experience IBS-like symptoms when their IBD is in remission. A three-year study found that patients diagnosed with IBS were 16.3 times more likely to be diagnosed with IBD during the study period. Serum markers associated with inflammation have also been found in patients with IBS.
Abdominal surgery: People with IBS were at increased risk of having unnecessary gall bladder removal surgery not due to an increased risk of gallstones, but rather to abdominal pain, awareness of having gallstones, and inappropriate surgical indications. These people also are 87% more likely to undergo abdominal and pelvic surgery and three times more likely to undergo gallbladder surgery. Also, people with IBS were twice as likely to undergo hysterectomy.
Other chronic disorders: Interstitial cystitis may be associated with other chronic pain syndromes, such as irritable bowel syndrome and fibromyalgia. The connection between these syndromes is unknown.
A 2018 systematic review found that although there is evidence of improved IBS symptoms with a low FODMAP diet; the evidence is of very low quality. Symptoms most likely to improve include urgency, flatulence, bloating, abdominal pain, and altered stool output. One national guideline advises a low FODMAP diet for managing IBS when other dietary and lifestyle measures have been unsuccessful. The diet restricts various carbohydrates which are poorly absorbed in the small intestine, as well as fructose and lactose, which are similarly poorly absorbed in those with intolerances to them. Reduction of fructose and fructan has been shown to reduce IBS symptoms in a dose-dependent manner in people with fructose malabsorption and IBS.
FODMAPs are fermentable oligo-, di-, monosaccharides and polyols, which are poorly absorbed in the small intestine and subsequently fermented by the bacteria in the distal small and proximal large intestine. This is a normal phenomenon, common to everyone. The resultant production of gas potentially results in bloating and flatulence. Although FODMAPs can produce certain digestive discomfort in some people, not only do they not cause intestinal inflammation, but they help avoid it, because they produce beneficial alterations in the intestinal flora that contribute to maintaining the good health of the colon. FODMAPs are not the cause of irritable bowel syndrome nor other functional gastrointestinal disorders, but rather a person develops symptoms when the underlying bowel response is exaggerated or abnormal.
A low-FODMAP diet consists in restricting them from the diet. They are globally trimmed, rather than individually, which is more successful than for example restricting only fructose and fructans, which are also FODMAPs, as is recommended for those with fructose malabsorption.
A low-FODMAP diet might help to improve short-term digestive symptoms in adults with irritable bowel syndrome, but its long-term follow-up can have negative effects because it causes a detrimental impact on the gut microbiota and metabolome. It should only be used for short periods of time and under the advice of a specialist. A low-FODMAP diet is highly restrictive in various groups of nutrients and can be impractical to follow in the long-term. More studies are needed to assess the true impact of this diet on health.
In addition, the use of a low-FODMAP diet without verifying the diagnosis of IBS may results in misdiagnosis of other conditions such as celiac disease. Since the consumption of gluten is suppressed or reduced with a low-FODMAP diet, the improvement of the digestive symptoms with this diet may not be related to the withdrawal of the FODMAPs, but of gluten, indicating the presence of an unrecognized celiac disease, avoiding its diagnosis and correct treatment, with the consequent risk of several serious health complications, including various types of cancer.
Some evidence suggests soluble fiber supplementation (e.g., psyllium/ispagula husk) is effective. It acts as a bulking agent, and for many people with IBS-D, allows for a more consistent stool. For people with IBS-C, it seems to allow for a softer, moister, more easily passable stool.
However, insoluble fiber (e.g., bran) has not been found to be effective for IBS. In some people, insoluble fiber supplementation may aggravate symptoms.
Fiber might be beneficial in those who have a predominance of constipation. In people who have IBS-C, soluble fiber can reduce overall symptoms, but will not reduce pain. The research supporting dietary fiber contains conflicting small studies complicated by the heterogeneity of types of fiber and doses used.
One meta-analysis found only soluble fiber improved global symptoms of irritable bowel, but neither type of fiber reduced pain.
An updated meta-analysis by the same authors also found soluble fiber reduced symptoms, while insoluble fiber worsened symptoms in some cases. Positive studies have used 10-30 grams per day of ispaghula (psyllium). One study specifically examined the effect of dose, and found 20 g of ispaghula (psyllium) were better than 10 g and equivalent to 30 g per day.
The use of antispasmodic drugs (e.g., anticholinergics such as hyoscyamine or dicyclomine) may help people who have cramps or diarrhea. A meta-analysis by the Cochrane Collaboration concludes if seven people are treated with antispasmodics, one of them will benefit. Antispasmodics can be divided into two groups: neurotropics and musculotropics. Musculotropics, such as mebeverine, act directly at the smooth muscle of the gastrointestinal tract, relieving spasm without affecting normal gut motility. Since this action is not mediated by the autonomic nervous system, the usual anticholinergic side effects are absent. The antispasmodic otilonium may also be useful.
Discontinuation of proton pump inhibitors
Proton pump inhibitors (PPIs) used to suppress stomach acid production may cause bacterial overgrowth leading to IBS symptoms. Discontinuation of PPIs in selected individuals has been recommended as it may lead to an improvement or resolution of IBS symptoms.
There is good evidence that low doses of tricyclic antidepressants can be effective for IBS. However, the evidence is less robust as to the effectiveness of other antidepressant classes such as selective serotonin reuptake inhibitor antidepressants (SSRIs). Antidepressants are not effective for IBS in people with depression, possible because lower doses of antidepressants than the doses used to treat depression are required for relief of IBS.
SSRIs, because of their serotonergic effect, have been studied to see if they help IBS, especially people who are constipation predominant but as of 2015 the evidence is that SSRIs do not help.
Evidence is conflicting about the benefit of antidepressants in IBS. Some meta-analyses have found a benefit, while others have not. With TCAs about one in three people improve.
Rifaximin may be useful as a treatment for IBS symptoms, including abdominal bloating and flatulence, although relief of abdominal distension is delayed. It is especially useful where small intestinal bacterial overgrowth is involved.
In individuals with IBS and low levels of vitamin D supplementation is recommended. Some evidence suggests that vitamin D supplementation may improve symptoms of IBS, but further research is needed before it can be recommended as a specific treatment for IBS.
Domperidone, a dopamine receptor blocker and a parasympathomimetic, has been shown to reduce bloating and abdominal pain as a result of an accelerated colon transit time and reduced fecal load, that is, a relief from 'hidden constipation'; defecation was similarly improved.
Reduction in IBS symptoms occurs following antibiotic therapy for small intestinal bacterial overgrowth. However, recent research has shown that the lactulose hydrogen breath test does not actually measure SIBO, and that SIBO is unlikely to be the cause of IBS.
There is low quality evidence from studies with poor methodological quality that psychological therapies can be effective in the treatment of IBS; however there are no significant adverse effects from psychological therapies for IBS. The mind-body or brain-gut interactions has been proposed for IBS, and is gaining increasing research attention.Hypnosis can improve mental well-being, and cognitive behavioural therapy can provide psychological coping strategies for dealing with distressing symptoms, as well as help suppress thoughts and behaviours that increase the symptoms of IBS. Although the evidence base for effectiveness of psychotherapy and hypnosis is weak and such therapies are in general not recommended, in treatment-resistant cases where pharmacological therapies over a period of at least 12 months have failed to give relief, NICE clinical guidelines recommend that consideration should be given to psychological treatment strategies such as cognitive behavioural therapy [CBT], hypnotherapy and/or psychological therapy.
Reducing stress may reduce the frequency and severity of IBS symptoms. Techniques that may be helpful include:
Regular exercise such as swimming, walking, or running
A meta-analysis found no benefits of acupuncture relative to placebo for IBS symptom severity or IBS-related quality of life.
Probiotics can be beneficial in the treatment of IBS; taking 10 billion to 100 billion beneficial bacteria per day is recommended for beneficial results. However, further research is needed on individual strains of beneficial bacteria for more refined recommendations. Probiotics have positive effects such as enhancing the intestinal mucosal barrier, providing a physical barrier, bacteriocin production (resulting in reduced numbers of pathogenic and gas-producing bacteria), reducing intestinal permeability and bacterial translocation, and regulating the immune system both locally and systemically among other beneficial effects. Probiotics may also have positive effects on the gut-brain axis by their positive effects countering the effects of stress on gut immunity and gut function.
A number of probiotics have been found to be effective, including Lactobacillus plantarum, and Bifidobacteria infantis; but one review found only Bifidobacteria infantis showed efficacy.B. infantis may have effects beyond the gut via it causing a reduction of proinflammatory cytokine activity and elevation of blood tryptophan levels, which may cause an improvement in symptoms of depression. Some yogurt is made using probiotics that may help ease symptoms of IBS. A probiotic yeast called Saccharomyces boulardii has some evidence of effectiveness in the treatment of irritable bowel syndrome.
Certain probiotics have different effects on certain symptoms of IBS. For example, Bifidobacterium breve, B. longum, and Lactobacillus acidophilus have been found to alleviate abdominal pain. B. breve, B. infantis, L. casei, or L. plantarum species alleviated distension symptoms. B. breve, B. infantis, L. casei, L. plantarum, B. longum, L. acidophilus, L. bulgaricus, and Streptococcus salivarius ssp. thermophilus have all been found to affect flatulence levels. Most clinical studies show probiotics do not improve straining, sense of incomplete evacuation, stool consistency, fecal urgency, or stool frequency, although a few clinical studies did find some benefit of probiotic therapy. The evidence is conflicting for whether probiotics improve overall quality of life scores.
Probiotics may exert their beneficial effects on IBS symptoms via preserving the gut microbiota, normalisation of cytokine blood levels, improving the intestinal transit time, decreasing small intestine permeability, and by treating small intestinal bacterial overgrowth of fermenting bacteria. A fecal transplant does not appear useful as of 2019.
Peppermint oil appears useful. In a meta-analysis it was found to be superior to placebo for improvement of IBS symptoms, at least in the short term. An earlier meta-analysis suggested the results of peppermint oil were tentative as the number of people studied was small and blinding of those receiving treatment was unclear. Safety during pregnancy has not been established, however, and caution is required not to chew or break the enteric coating; otherwise, gastroesophageal reflux may occur as a result of lower esophageal sphincter relaxation. Occasionally, nausea and perianal burning occur as side effects.Iberogast, a multi-herbal extract, was found to be superior in efficacy to placebo.
Only limited evidence exists for the effectiveness of other herbal remedies for IBS. As with all herbs, it is wise to be aware of possible drug interactions and adverse effects.
Percentage of population with IBS reported in various studies in different countries
The prevalence of IBS varies by country and by age range examined. The bar graph at right shows the percentage of the population reporting symptoms of IBS in studies from various geographic regions (see table below for references). The following table contains a list of studies performed in different countries that measured the prevalence of IBS and IBS-like symptoms:
Percentage of population reporting symptoms of IBS in various studies from various geographic areas
Study measured prevalence of GI abdominal pain/cramping
Women are around two to three times more likely to be diagnosed with IBS and four to five times more likely to seek specialty care for it than men. These differences likely reflect a combination of both biological (sex) and social (gender) factors. People diagnosed with IBS are usually younger than 45 years old. Studies of females with IBS show symptom severity often fluctuates with the menstrual cycle, suggesting hormonal differences may play a role. Endorsement of gender-related traits has been associated with quality of life and psychological adjustment in IBS. Gender differences in healthcare-seeking may also play a role. Gender differences in trait anxiety may contribute to lower pain thresholds in women, putting them at greater risk for a number of chronic pain disorders. Finally, sexual trauma is a major risk factor for IBS, with as many as 33% of those affected reporting such abuse. Because women are at higher risk of sexual abuse than men, sex-related risk of abuse may contribute to the higher rate of IBS in women.
The concept of an "irritable bowel" appeared in the Rocky Mountain Medical Journal in 1950. The term was used to categorize people who developed symptoms of diarrhea, abdominal pain, and constipation, but where no well-recognized infective cause could be found. Early theories suggested the irritable bowel was caused by a psychosomatic or mental disorder.
Society and culture
Other names for the condition used in the past included irritable colon, spastic colon, nervous colon, colitis, mucous colitis, and spastic bowel.
The terminologies that refer to the colon are inaccurate and discouraged, since the disorder is not limited to this section of the digestive tract. Similarly, the term "colitis" is not accurate as inflammation is not present. Other reasons why these terms were abandoned were to reflect the understanding that the disorder is not a figment of a person's imagination.
The aggregate cost of irritable bowel syndrome in the United States has been estimated at $1.7-10 billion in direct medical costs, with an additional $20 billion in indirect costs, for a total of $21.7-30 billion. A study by a managed care company comparing medical costs for people with IBS to non-IBS controls identified a 49% annual increase in medical costs associated with a diagnosis of IBS. People with IBS incurred average annual direct costs of $5,049 and $406 in out-of-pocket expenses in 2007. A study of workers with IBS found that they reported a 34.6% loss in productivity, corresponding to 13.8 hours lost per 40 hour week. A study of employer-related health costs from a Fortune 100 company conducted with data from the 1990s found people with IBS incurred US $4527 in claims costs vs. $3276 for controls. A study on Medicaid costs conducted in 2003 by the University of Georgia's College of Pharmacy and Novartis found IBS was associated in an increase of $962 in Medicaid costs in California, and $2191 in North Carolina. People with IBS had higher costs for physician visits, outpatients visits, and prescription drugs. The study suggested the costs associated with IBS were comparable to those found for people with asthma.
Individuals with IBS have been found to have decreased diversity and numbers of bacteroidetes microbiota. Preliminary research into the effectiveness of fecal microbiota transplant in the treatment of IBS has been very favourable with a 'cure' rate of between 36 percent and 60 percent with remission of core IBS symptoms persisting at 9 and 19 months follow up. Treatment with probiotic strains of bacteria has shown to be effective, though not all strains of microorganisms confer the same benefit and adverse side effects have been documented in a minority of cases.
There is increasing evidence for the effectiveness of mesalazine (5-aminosalicylic acid) in the treatment of IBS. Mesalazine is a drug with anti-inflammatory properties that has been reported to significantly reduce immune mediated inflammation in the gut of IBS affected individuals with mesalazine therapy resulting in improved IBS symptoms as well as feelings of general wellness in IBS affected people. It has also been observed that mesalazine therapy helps to normalise the gut flora which is often abnormal in people who have IBS. The therapeutic benefits of mesalazine may be the result of improvements to the epithelial barrier function. Treatment based on "abnormally" high IgG antibodies cannot be recommended.
Differences in visceral sensitivity and intestinal physiology have been noted in IBS. Mucosal barrier reinforcement in response to oral 5-HTP was absent in IBS compared to controls. IBS/IBD individuals are less often HLA DQ2/8 positive than in upper functional gastrointestinal disease and healthy populations.
^ abQuigley, Eamonn M.M. (2013). "Treatment level 1". Irritable Bowel Syndrome: Diagnosis and Clinical Management (First ed.). Chichester, West Sussex: Wiley-Blackwell. ISBN9781118444740. Archived from the original on September 8, 2017.
^ abcdAlexandros Hadjivasilis, Constantinos Tsioutis, Adamantios Michalinos, Dimitrios Ntourakis, Dimitrios K. Christodoulou, and Aris P. Agouridis (2019). "New insights into irritable bowel syndrome: from pathophysiology to treatment". Ann Gastroenterol. 32 (6): 554-564. doi:10.20524/aog.2019.0428. PMID31700231.CS1 maint: uses authors parameter (link)
^ abcWhitehead WE, Palsson O, Jones KR (April 2002). "Systematic review of the comorbidity of irritable bowel syndrome with other disorders: what are the causes and implications?". Gastroenterology. 122 (4): 1140-56. doi:10.1053/gast.2002.32392. PMID11910364.
^ abMoayyedi P, Quigley EM, Lacy BE, Lembo AJ, Saito YA, Schiller LR, Soffer EE, Spiegel BM, Ford AC (September 2014). "The effect of fiber supplementation on irritable bowel syndrome: a systematic review and meta-analysis". The American Journal of Gastroenterology. 109 (9): 1367-74. doi:10.1038/ajg.2014.195. PMID25070054.
^ abcdRao SS, Yu S, Fedewa A (June 2015). "Systematic review: dietary fibre and FODMAP-restricted diet in the management of constipation and irritable bowel syndrome". Alimentary Pharmacology & Therapeutics. 41 (12): 1256-70. doi:10.1111/apt.13167. PMID25903636.
^Fukudo S, Nomura T, Muranaka M, Taguchi F (September 1993). "Brain-gut response to stress and cholinergic stimulation in irritable bowel syndrome. A preliminary study". Journal of Clinical Gastroenterology. 17 (2): 133-41. doi:10.1097/00004836-199309000-00009. PMID8031340.
^Barreau F, Ferrier L, Fioramonti J, Bueno L (September 2007). "New insights in the etiology and pathophysiology of irritable bowel syndrome: contribution of neonatal stress models". Pediatric Research. 62 (3): 240-5. doi:10.1203/PDR.0b013e3180db2949. PMID17622962.
^Fukudo S (January 2007). "Role of corticotropin-releasing hormone in irritable bowel syndrome and intestinal inflammation". Journal of Gastroenterology. 42 (Suppl 17): 48-51. doi:10.1007/s00535-006-1942-7. PMID17238026.
^Ghoshal UC, Gwee KA (July 2017). "Post-infectious IBS, tropical sprue and small intestinal bacterial overgrowth: the missing link". Nature Reviews. Gastroenterology & Hepatology. 14 (7): 435-441. doi:10.1038/nrgastro.2017.37. PMID28513629.
^Chen, B; Kim, JJ; Zhang, Y; Du, L; Dai, N (July 2018). "Prevalence and predictors of small intestinal bacterial overgrowth in irritable bowel syndrome: a systematic review and meta-analysis". Journal of gastroenterology. 53 (7): 807-818. doi:10.1007/s00535-018-1476-9. PMID29761234.
^Amin OM (June 2002). "Seasonal prevalence of intestinal parasites in the United States during 2000". The American Journal of Tropical Medicine and Hygiene. 66 (6): 799-803. doi:10.4269/ajtmh.2002.66.799. PMID12224595.
^ abStark D, van Hal S, Marriott D, Ellis J, Harkness J (January 2007). "Irritable bowel syndrome: a review on the role of intestinal protozoa and the importance of their detection and diagnosis". International Journal for Parasitology. 37 (1): 11-20. doi:10.1016/j.ijpara.2006.09.009. PMID17070814.
^Rostami A, Riahi SM, Haghighi A, Saber V, Armon B, Seyyedtabaei SJ (September 2017). "The role of Blastocystis sp. and Dientamoeba fragilis in irritable bowel syndrome: a systematic review and meta-analysis". Parasitology Research. 116 (9): 2361-2371. doi:10.1007/s00436-017-5535-6. PMID28668983.
^ abFerguson LR, Laing B, Marlow G, Bishop K (January 2016). "The role of vitamin D in reducing gastrointestinal disease risk and assessment of individual dietary intake needs: Focus on genetic and genomic technologies". Molecular Nutrition & Food Research. 60 (1): 119-33. doi:10.1002/mnfr.201500243. PMID26251177.
^Barbalho SM, Goulart RA, Araújo AC, Guiguer ÉL, Bechara MD (April 2019). "Irritable bowel syndrome: a review of the general aspects and the potential role of vitamin D". Expert Rev Gastroenterol Hepatol. 13 (4): 345-359. doi:10.1080/17474124.2019.1570137. PMID30791775.
^Verstraelen TE, Ter Bekke RM, Volders PG, Masclee AA, Kruimel JW (2015). "The role of the SCN5A-encoded channelopathy in irritable bowel syndrome and other gastrointestinal disorders". Neurogastroenterology & Motility. 27 (7): 906-13. doi:10.1111/nmo.12569. PMID25898860.
^Cremon C, Carini G, De Giorgio R, Stanghellini V, Corinaldesi R, Barbara G (May 2010). "Intestinal dysbiosis in irritable bowel syndrome: etiological factor or epiphenomenon?". Expert Review of Molecular Diagnostics. 10 (4): 389-93. doi:10.1586/erm.10.33. PMID20465494.
^Schmulson M, Bielsa MV, Carmona-Sánchez R, Hernández A, López-Colombo A, López Vidal Y, Peláez-Luna M, Remes-Troche JM, Tamayo JL, Valdovinos MA (2014). "Microbiota, gastrointestinal infections, low-grade inflammation, and antibiotic therapy in irritable bowel syndrome: an evidence-based review". Revista de Gastroenterologia de Mexico (in Spanish). 79 (2): 96-134. doi:10.1016/j.rgmx.2014.01.004. PMID24857420.
^Fass R, Longstreth GF, Pimentel M, Fullerton S, Russak SM, Chiou CF, Reyes E, Crane P, Eisen G, McCarberg B, Ofman J (September 2001). "Evidence- and consensus-based practice guidelines for the diagnosis of irritable bowel syndrome". Archives of Internal Medicine. 161 (17): 2081-8. doi:10.1001/archinte.161.17.2081. PMID11570936.
^Talley NJ (2006). "A unifying hypothesis for the functional gastrointestinal disorders: really multiple diseases or one irritable gut?". Reviews in Gastroenterological Disorders. 6 (2): 72-8. PMID16699476.
^ abcdefghiVolta U, Caio G, De Giorgio R, Henriksen C, Skodje G, Lundin KE (June 2015). "Non-celiac gluten sensitivity: a work-in-progress entity in the spectrum of wheat-related disorders". Best Practice & Research. Clinical Gastroenterology. 29 (3): 477-91. doi:10.1016/j.bpg.2015.04.006. PMID26060112.
^Rossi A, Di Lollo AC, Guzzo MP, Giacomelli C, Atzeni F, Bazzichi L, Di Franco M (2015). "Fibromyalgia and nutrition: what news?". Clinical and Experimental Rheumatology. 33 (1 Suppl 88): S117-25. PMID25786053.
^San Mauro Martín I, Garicano Vilar E, Collado Yurrutia L, Ciudad Cabañas MJ (December 2014). "[Is gluten the great etiopathogenic agent of disease in the XXI century?]". Nutricion Hospitalaria. 30 (6): 1203-10. doi:10.3305/nh.2014.30.6.7866. PMID25433099.
^Su YC, Wang WM, Wang SY, Lu SN, Chen LT, Wu DC, Chen CY, Jan CM, Horowitz M (August 2000). "The association between Helicobacter pylori infection and functional dyspepsia in patients with irritable bowel syndrome". The American Journal of Gastroenterology. 95 (8): 1900-5. doi:10.1111/j.1572-0241.2000.02252.x. PMID10950033.
^Gerards C, Leodolter A, Glasbrenner B, Malfertheiner P (2001). "H. pylori infection and visceral hypersensitivity in patients with irritable bowel syndrome". Digestive Diseases. 19 (2): 170-3. doi:10.1159/000050673. PMID11549828.
^Vernia P, Ricciardi MR, Frandina C, Bilotta T, Frieri G (April 1995). "Lactose malabsorption and irritable bowel syndrome. Effect of a long-term lactose-free diet". The Italian Journal of Gastroenterology. 27 (3): 117-21. PMID7548919.
^Wedlake L, A'Hern R, Russell D, Thomas K, Walters JR, Andreyev HJ (October 2009). "Systematic review: the prevalence of idiopathic bile acid malabsorption as diagnosed by SeHCAT scanning in patients with diarrhoea-predominant irritable bowel syndrome". Alimentary Pharmacology & Therapeutics. 30 (7): 707-17. doi:10.1111/j.1365-2036.2009.04081.x. PMID19570102.
^Simrén M, Axelsson J, Gillberg R, Abrahamsson H, Svedlund J, Björnsson ES (February 2002). "Quality of life in inflammatory bowel disease in remission: the impact of IBS-like symptoms and associated psychological factors". The American Journal of Gastroenterology. 97 (2): 389-96. doi:10.1111/j.1572-0241.2002.05475.x. PMID11866278.
^Minderhoud IM, Oldenburg B, Wismeijer JA, van Berge Henegouwen GP, Smout AJ (March 2004). "IBS-like symptoms in patients with inflammatory bowel disease in remission; relationships with quality of life and coping behavior". Digestive Diseases and Sciences. 49 (3): 469-74. doi:10.1023/B:DDAS.0000020506.84248.f9. PMID15139501.
^García Rodríguez LA, Ruigómez A, Wallander MA, Johansson S, Olbe L (March 2000). "Detection of colorectal tumor and inflammatory bowel disease during follow-up of patients with initial diagnosis of irritable bowel syndrome". Scandinavian Journal of Gastroenterology. 35 (3): 306-11. doi:10.1080/003655200750024191. PMID10766326.
^Corazziari E, Attili AF, Angeletti C, De Santis A (December 2008). "Gallstones, cholecystectomy and irritable bowel syndrome (IBS) MICOL population-based study". Digestive and Liver Disease. 40 (12): 944-50. doi:10.1016/j.dld.2008.02.013. PMID18406218.
^Cole JA, Yeaw JM, Cutone JA, Kuo B, Huang Z, Earnest DL, Walker AM (December 2005). "The incidence of abdominal and pelvic surgery among patients with irritable bowel syndrome". Digestive Diseases and Sciences. 50 (12): 2268-75. doi:10.1007/s10620-005-3047-1. PMID16416174.
^Ford AC, Quigley EM, Lacy BE, Lembo AJ, Saito YA, Schiller LR, Soffer EE, Spiegel BM, Moayyedi P (September 2014). "Effect of antidepressants and psychological therapies, including hypnotherapy, in irritable bowel syndrome: systematic review and meta-analysis". The American Journal of Gastroenterology. 109 (9): 1350-65, quiz 1366. doi:10.1038/ajg.2014.148. PMID24935275.
^ abcdStaudacher HM, Irving PM, Lomer MC, Whelan K (April 2014). "Mechanisms and efficacy of dietary FODMAP restriction in IBS". Nature Reviews. Gastroenterology & Hepatology (Review). 11 (4): 256-66. doi:10.1038/nrgastro.2013.259. PMID24445613. An emerging body of research now demonstrates the efficacy of fermentable carbohydrate restriction in IBS. [...] However, further work is urgently needed both to confirm clinical efficacy of fermentable carbohydrate restriction in a variety of clinical subgroups and to fully characterize the effect on the gut microbiota and the colonic environ¬ment. Whether the effect on luminal bifidobacteria is clinically relevant, preventable, or long lasting, needs to be investigated. The influence on nutrient intake, dietary diversity, which might also affect the gut microbiota,137 and quality of life also requires further exploration as does the possible economic effects due to reduced physician contact and need for medication. Although further work is required to confirm its place in IBS and functional bowel disorder clinical pathways, fermentable carbohydrate restriction is an important consideration for future national and international IBS guidelines.
^Andoh A, Tsujikawa T, Fujiyama Y (2003). "Role of dietary fiber and short-chain fatty acids in the colon". Current Pharmaceutical Design (Review). 9 (4): 347-58. doi:10.2174/1381612033391973. PMID12570825.
^Marsh A, Eslick EM, Eslick GD (April 2016). "Does a diet low in FODMAPs reduce symptoms associated with functional gastrointestinal disorders? A comprehensive systematic review and meta-analysis". European Journal of Nutrition. 55 (3): 897-906. doi:10.1007/s00394-015-0922-1. PMID25982757.
^Tuck CJ, Muir JG, Barrett JS, Gibson PR (September 2014). "Fermentable oligosaccharides, disaccharides, monosaccharides and polyols: role in irritable bowel syndrome". Expert Review of Gastroenterology & Hepatology. 8 (7): 819-34. doi:10.1586/17474124.2014.917956. PMID24830318.
^ abBarrett JS (March 2017). "How to institute the low-FODMAP diet". Journal of Gastroenterology and Hepatology (Review). 32 (Suppl 1): 8-10. doi:10.1111/jgh.13686. PMID28244669. Common symptoms of IBS are bloating, abdominal pain, excessive flatus, constipation, diarrhea, or alternating bowel habit. These symptoms, however, are also common in the presentation of coeliac disease, inflammatory bowel disease, defecatory disorders, and colon cancer. Confirming the diagnosis is crucial so that appropriate therapy can be undertaken. Unfortunately, even in these alternate diagnoses, a change in diet restricting FODMAPs may improve symptoms and mask the fact that the correct diagnosis has not been made. This is the case with coeliac disease where a low-FODMAP diet can concurrently reduce dietary gluten, improving symptoms, and also affecting coeliac diagnostic indices.3,4 Misdiagnosis of intestinal diseases can lead to secondary problems such as nutritional deficiencies, cancer risk, or even mortality in the case of colon cancer.
^Jackson JL, O'Malley PG, Tomkins G, Balden E, Santoro J, Kroenke K (January 2000). "Treatment of functional gastrointestinal disorders with antidepressant medications: a meta-analysis". The American Journal of Medicine. 108 (1): 65-72. doi:10.1016/S0002-9343(99)00299-5. PMID11059442.
^ abFord AC, Harris LA, Lacy BE, Quigley EM, Moayyedi P (November 2018). "Systematic review with meta-analysis: the efficacy of prebiotics, probiotics, synbiotics and antibiotics in irritable bowel syndrome". Alimentary Pharmacology & Therapeutics. 48 (10): 1044-1060. doi:10.1111/apt.15001. PMID30294792.
^Raahave D, Christensen E, Loud FB, Knudsen LL. "Correlation of bowel symptoms with colonic transit, length, and faecal load in functional faecal retention" 2009; 56: 83-8
^Nikfar S, Rahimi R, Rahimi F, Derakhshani S, Abdollahi M (December 2008). "Efficacy of probiotics in irritable bowel syndrome: a meta-analysis of randomized, controlled trials". Diseases of the Colon and Rectum. 51 (12): 1775-80. doi:10.1007/s10350-008-9335-z. PMID18465170.
^Konturek PC, Brzozowski T, Konturek SJ (December 2011). "Stress and the gut: pathophysiology, clinical consequences, diagnostic approach and treatment options". Journal of Physiology and Pharmacology. 62 (6): 591-9. PMID22314561.
^Brenner DM, Moeller MJ, Chey WD, Schoenfeld PS (April 2009). "The utility of probiotics in the treatment of irritable bowel syndrome: a systematic review". The American Journal of Gastroenterology. 104 (4): 1033-49, quiz 1050. doi:10.1038/ajg.2009.25. PMID19277023.
^Xu, D; Chen, VL; Steiner, CA; Berinstein, JA; Eswaran, S; Waljee, AK; Higgins, PDR; Owyang, C (July 2019). "Efficacy of Fecal Microbiota Transplantation in Irritable Bowel Syndrome: A Systematic Review and Meta-Analysis". The American Journal of Gastroenterology. 114 (7): 1043-1050. doi:10.14309/ajg.0000000000000198. PMID30908299.
^Wilkins T, Pepitone C, Alex B, Schade RR (September 2012). "Diagnosis and management of IBS in adults". American Family Physician. 86 (5): 419-26. PMID22963061.
^Rösch W, Liebregts T, Gundermann KJ, Vinson B, Holtmann G (2006). "Phytotherapy for functional dyspepsia: a review of the clinical evidence for the herbal preparation STW 5". Phytomedicine. 13 (Suppl 5): 114-21. doi:10.1016/j.phymed.2006.03.022. PMID16978851.
Boivin M (October 2001). "Socioeconomic impact of irritable bowel syndrome in Canada". Canadian Journal of Gastroenterology. 15 (Suppl B): 8B-11B. doi:10.1155/2001/401309. PMID11694908.
Quigley EM, Locke GR, Mueller-Lissner S, Paulo LG, Tytgat GN, Helfrich I, Schaefer E (July 2006). "Prevalence and management of abdominal cramping and pain: a multinational survey". Alimentary Pharmacology & Therapeutics. 24 (2): 411-9. doi:10.1111/j.1365-2036.2006.02989.x. PMID16842469.
Hungin AP, Chang L, Locke GR, Dennis EH, Barghout V (June 2005). "Irritable bowel syndrome in the United States: prevalence, symptom patterns and impact". Alimentary Pharmacology & Therapeutics. 21 (11): 1365-75. doi:10.1111/j.1365-2036.2005.02463.x. PMID15932367.
^Jafri W, Yakoob J, Jafri N, Islam M, Ali QM (June 2007). "Irritable bowel syndrome and health seeking behaviour in different communities of Pakistan". JPMA. The Journal of the Pakistan Medical Association. 57 (6): 285-7. PMID17629228.
^Jafri W, Yakoob J, Jafri N, Islam M, Ali QM (2005). "Frequency of irritable bowel syndrome in college students". Journal of Ayub Medical College, Abbottabad. 17 (4): 9-11. PMID16599025.
^Schmulson M, Ortíz O, Santiago-Lomeli M, Gutiérrez-Reyes G, Gutiérrez-Ruiz MC, Robles-Díaz G, Morgan D (2006). "Frequency of functional bowel disorders among healthy volunteers in Mexico City". Digestive Diseases. 24 (3-4): 342-7. doi:10.1159/000092887. PMID16849861.
^Jackson NA, Houghton LA, Whorwell PJ, Currer B (December 1994). "Does the menstrual cycle affect anorectal physiology?". Digestive Diseases and Sciences. 39 (12): 2607-11. doi:10.1007/bf02087697. PMID7995186.
^Voci SC, Cramer KM (November 2009). "Gender-related traits, quality of life, and psychological adjustment among women with irritable bowel syndrome". Quality of Life Research. 18 (9): 1169-76. doi:10.1007/s11136-009-9532-9. PMID19728159.
^Drossman DA, Li Z, Andruzzi E, Temple RD, Talley NJ, Thompson WG, Whitehead WE, Janssens J, Funch-Jensen P, Corazziari E (September 1993). "U.S. householder survey of functional gastrointestinal disorders. Prevalence, sociodemography, and health impact". Digestive Diseases and Sciences. 38 (9): 1569-80. doi:10.1007/bf01303162. PMID8359066.
^Goffaux P, Michaud K, Gaudreau J, Chalaye P, Rainville P, Marchand S (September 2011). "Sex differences in perceived pain are affected by an anxious brain". Pain. 152 (9): 2065-73. doi:10.1016/j.pain.2011.05.002. PMID21665365.
^García MD, García JI, Pereda A (2002). "Trastornos intestinales funcionales (equivalentes del colon irritable)". Sociedad Española de Gastroenterología, Hepatología y Nutrición Pediátrica (Review) (in Spanish). 57 (3): 253-63. doi:10.1016/S1695-4033(02)77914-9.
^Levy RL, Von Korff M, Whitehead WE, Stang P, Saunders K, Jhingran P, Barghout V, Feld AD (November 2001). "Costs of care for irritable bowel syndrome patients in a health maintenance organization". The American Journal of Gastroenterology. 96 (11): 3122-9. doi:10.1111/j.1572-0241.2001.05258.x. PMID11721759.
^Paré P, Gray J, Lam S, Balshaw R, Khorasheh S, Barbeau M, Kelly S, McBurney CR (October 2006). "Health-related quality of life, work productivity, and health care resource utilization of subjects with irritable bowel syndrome: baseline results from LOGIC (Longitudinal Outcomes Study of Gastrointestinal Symptoms in Canada), a naturalistic study". Clinical Therapeutics. 28 (10): 1726-35, discussion 1710-1. doi:10.1016/j.clinthera.2006.10.010. PMID17157129.
^Leong SA, Barghout V, Birnbaum HG, Thibeault CE, Ben-Hamadi R, Frech F, Ofman JJ (April 2003). "The economic consequences of irritable bowel syndrome: a US employer perspective". Archives of Internal Medicine. 163 (8): 929-35. doi:10.1001/archinte.163.8.929. PMID12719202.
^Ford AC, Quigley EM, Lacy BE, Lembo AJ, Saito YA, Schiller LR, Soffer EE, Spiegel BM, Moayyedi P (October 2014). "Efficacy of prebiotics, probiotics, and synbiotics in irritable bowel syndrome and chronic idiopathic constipation: systematic review and meta-analysis". The American Journal of Gastroenterology. 109 (10): 1547-61, quiz 1546, 1562. doi:10.1038/ajg.2014.202. PMID25070051.
^Klotz U (February 2012). "The pharmacological profile and clinical use of mesalazine (5-aminosalicylic acid)". Arzneimittel-Forschung. 62 (2): 53-8. doi:10.1055/s-0031-1299685. PMID22344548.
^Barbara G, et al. (2009). "Aminosalicylates and other anti-inflammatory compounds for irritable bowel syndrome". Digestive Diseases. 27 (Suppl 1): 115-21. doi:10.1159/000268131. PMID20203507.