Digestion and metabolism of food is a very important function of the digestive system. However, digestion and metabolism of food may have some problems in the few people, Variety of conditions are linked to pathological state of organs in digestive system.
IBS or irritable bowel syndrome is one of them. Bowel and bladder plays major role in maintaining the metabolism of body. Irritable bowel syndrome is a condition which is characterised by abdominal pain, change in bowel habits without underlying cause .
The symptoms are noted over a period of time and without any visible damage to the gastrointestinal system.
WHAT IS IBS ?
Irritable bowel syndrome is a group of symptoms that occur together including repeated pain in abdomen and changes in bowel movement. It may include constipation or diarrhea or both.
IBS also known as spastic colon, irritable colon, mucous colitis, and spastic colitis. It is a separate condition from Inflammatory bowel disease. The symptoms vary in severity and duration from person to person. However, they last at least three months for at least three days per month.
IBS can cause intestinal damage in some cases. However, that is not common.
IBS doesn’t increase your risk of gastrointestinal cancers, but it can still have a significant effect on your life.
CLASSIFICATION OF IBS:
There are 3 types of Irritable bowel syndrome, they are as follows
IBS with constipation (IBS-C)
IBS with diarrhea (IBS-D)
IBS with mixed bowel habits (IBS-M)
IBS with constipation (IBS-C) : With IBS-C, on days when you have at least one abnormal bowel movement
more than a quarter of your stools are hard or lumpy and
less than a quarter of your stools are loose or watery
IBS with diarrhea (IBS- D) : In IBS-D, on days when you have at least one abnormal bowel movement
more than a quarter of your stools are loose or watery and
less than a quarter of your stools are hard or lumpy
IBS with mixed bowel habits (IBS-M): In IBS-M, on days when you have at least one abnormal bowel movement
more than a quarter of your stools are hard or lumpy and
more than a quarter of your stools are loose or watery
PEOPLE AT RISK
As always, there are some risk factors associated with IBS. Few people are more prone to develop IBS than others. People who are at risk are as follows;
Women are more likely to develop IBS than males. The risk is almost double which means, women are twice more likely to develop IBS.
People who are younger than 50 years of age are more prone to develop IBS than people who are higher than 50 years.
The other factors increasing the chances of IBS are as follows;
having a family member with IBS
a history of stressful or difficult life events, such as abuse, in childhood
having a severe infection in your digestive tract
The risk of developing IBS increases six-fold after acute gastrointestinal infection.
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.
Antibiotic use also appears to increase the risk of developing IBS.
1. CAUSES OF IBS
IBS is a functional gastrointestinal (GI) disorder. Functional GI disorders, which doctors now call disorders of gut-brain interactions, are related to problems with how your brain and your gut work together.
These problems can cause your gut to be more sensitive and change how the muscles in your bowel contract. If your gut is more sensitive, you may feel more abdominal pain and bloating. Changes in how the muscles in your bowel contract lead to diarrhea, constipation, or both.
Studies have shown that gut brain axis plays an important role in causing IBS. childhood physical and psychological abuse is often associated with the development of IBS. It is observed that psychological stress may trigger IBS in people who are already predisposed to the conditions.
The stress response in body involves hypothalamus-pituitary- adrenal axis and sympathetic nervous system affect the 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 released from the 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 immunity 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 commensal bacteria across 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.
According to studies, small intestinal bacterial overgrowth occurs in people who have been diagnosed with IBS as compared to the healthy individuals.
Symptoms of bacterial overgrowth include abdominal bloating, diarrhea or constipation. IBS may be the result of the immune system interacting abnormally with gut microbiota resulting in an abnormal cytokine signaling profile.
1.5. Other microorganisms
Other microorganisms like fungus , protozoa are also responsible to cause some types of IBS.
1.6. Vitamin D
Vitamin D is involved in regulating triggers for IBS including the gut microbiome, inflammatory processes and immune responses, as well as psychosocial factors. People having IBS may have deficiency of vitamin D . So many times vitamin D deficiency is associated with IBS.
2. SYMPTOMS OF IBS
The symptoms of IBS are as follows;
2.2 Abdominal Pain: You may experience stomach cramping after eating a meal. It may get better after you have a bowel movement.
2.3 Bloating and Gas: If your stomach often feels bloated, it may be a sign of IBS. Abdominal bloating causes your midsection to feel tight and full.
Certain food cause gas or flatulence. The foodstuff causing gas are ;
Cabbage, beans, some milk products, fried food, drinks containing caffeine, alcohol.
2.4 Constipation: These may have symptoms like straining to pass stools.
2.5 Diarrhea: If you pass loose stool multiple times a day, you may have IBS-related diarrhea if. It can also cause feelings of urgency when you need to have a bowel movement.
2.6 SYMPTOMS OF IBS IN WOMEN
Women are generally diagnosed with IBS during their childbearing years. Women with IBS also tend to report more gynecologic disorders.
Many women with IBS say their symptoms vary according to their menstrual cycles. Prior to and during their period, women with IBS may report having more abdominal pain and diarrhea. After ovulation (day 14 of a cycle), women with IBS may feel more bloating and constipation.
As many as one third of all pregnant women say they have increased heartburn, nausea, and bowel movements or constipation compared to when they weren’t pregnant. When it comes to linking pregnancy with an increase in symptoms of IBS, not much research has been done. More studies are needed to find out if these symptoms are due to the physical pressure of the fetus on your internal organs or to IBS.
Women who have IBS are more likely to experience, Fatigue, Insomnia, food sensitivity, backache, cramping, premenstrual syndrome.
2.7 SYMPTOMS OF IBS IN MEN
Studies show that men in Western countries are less likely than women to report symptoms of IBS to their doctor.
Some researchers suggest that due to hormonal differences, the male gut may be less sensitive to the symptoms of IBS.
Like women, men with IBS may experience a problem with sexual intimacy. Men with IBS may also face difficulty fulfilling their work, home, and social obligations. They’re also more likely to suffer from depression.
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.
Rome Criteria is used for diagnosis, The diagnosis by using Rome criteria is as follows;
The Rome IV criteria include recurrent abdominal pain, on average, at least 1 day/week in the last 3 months, associated with two or more of the following further 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 stools.
Investigations are performed to exclude other conditions:
Stool microscopy and culture (to exclude infectious conditions)
Blood tests: Full blood examination, liver function tests, erythrocyte sedimentation rate, and serological testing for coeliac disease
Abdominal ultrasound (to exclude gallstones and other biliary tract diseases)
Endoscopy and biopsies (to exclude peptic ulcer disease, coeliac disease, inflammatory bowel disease, and malignancies)
Hydrogen breath testing (to exclude fructose and lactose malabsorption)
4.1 Medicatons : There are few medications prescribed by FDA for IBS.
Alosetron hydrochloride (Lotronex): The FDA approved this medication for the treatment of IBS with diarrhea (IBS-D). The medication is a 5-HT3 blocker.
Eluxadoline (Viberzi): In May 2015, the FDA approved this medication for the treatment of IBS-D. This medication is designed to affect the nervous system by reducing bowel contractions that cause diarrhea.
Lubiprostone (Amitiza): This medication is used to treat IBS with constipation (IBS-C) in women ages 18 and older. It works by activating chloride channels in the body to reduce symptoms of constipation.
Rifaximin (Xifaxan): The FDA also approved this antibiotic to treat IBS in May 2015. This medication is intended to be taken three times a day for 14 days to reduce the symptoms of IBS-D. While doctors don’t know exactly how the drug works, Xifaxan has been thought to affect the bacteria in your gastrointestinal (GI) tract to reduce symptoms associated with IBS-D.
Along with these medications other specific medicines may be prescribed. These medicines include drugs like anti depressants, anti diarrheal, anti spasmodic , laxative, fiber supplement, probiotics.
Ideally, lifestyle changes can help you control your IBS. However, if your symptoms worsen or affect your daily life, your healthcare provider may prescribe one or more of these medications.
4.2 Lifestyle Modifications: Sometimes treatments for IBS don’t come in pill form. Because diet, stress, and anxiety can all play roles in worsening IBS, lifestyle changes could reduce your symptoms. One place to start is your diet.
Some foods can cause uncomfortable gas and bloating. Your healthcare provider may recommend eliminating veggies like broccoli, cauliflower, and cabbage to see if your symptoms improve. Carbonated drinks and raw fruits may also cause excess gas and bloating.
Stress relief is one important aspect of lifestyle modifications. Various techniques like, pursuing a hobby, listening to music or some form of exercises and meditation may help in coping with stress.
Taking a little quiet time for yourself — even just 15 minutes a day — can help relieve feelings of stress and pressure. You may benefit from seeing a therapist who can help you recognize stressors in your life and learn how to cope.
Quitting smoking or other addictions are equally crucial to manage lifestyle disorders.
4.3 Diet: 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.
FODMAP stands for fermentable oligo-, di-, and monosaccharides and polyols. These types of carbohydrates can irritate the digestive tract when you have IBS.
An elimination diet, where you stop eating these food types to see if your symptoms improve, may be recommended. You may then slowly reintroduce some of the foods. If your symptoms come back, you know which food could be one of the causes.
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.
Sometimes adding fiber into your diet can help reduce the effects of constipation.
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.
4.4 Psychological Therapies: 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.
Therapies like hypnosis and cognitive behavioural therapies may improve and help in coping with stress and other mental issues which may cause trigger for IBS.
NICE clinical guidelines recommend that consideration should be given to psychological treatment strategies such as cognitive behavioural therapy [CBT], hypnotherapy and/or psychological therapy.
4.5 Herbal Remedies: Peppermint oil is found to be beneficial. 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.
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.
4.6 Probiotics: Probiotic 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 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.
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 distention symptom.
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.
4.7 Other Agents: Magnesium Aluminium silicates and alverine citrate can be useful in treatment of IBS.
Rifaximin can be useful in IBS associated symptoms like, abdominal pain, gas , flatulence.
Some individuals have IBS associated with vitamin D deficiency. In such cases, taking vitamin D supplements may be useful and help in reducing symptoms of IBS.
Domeperidone, A dopamine receptor blocker and a parasympathetomimetic, has been found