Fibromyalgia and Irritable Bowel Syndrome
Fibromyalgia and Irritable Bowel Syndrome are co-diagnosed in up to 70% of Fibromyalgia patients. Irritable bowel syndrome (IBS; also known as irritable colon, spastic colon, mucous colitis, or spastic colitis) is a disorder of the bowel, or large intestine. It is characterized by severe abdominal pain and cramping, changes in bowel movements, and a variety of other symptoms. It is important to note that IBS is not the same condition as inflammatory bowel disease, which includes the conditions Chrohn’s disease and ulcerative colitis.
Most cases of IBS have an unknown cause, although some can result following an intestinal infection. There may also be neural (nerve) triggers. The brain and intestines are connected by a large network of nerves. These nerves send signals to affect intestinal function and symptoms, and sometimes the nerves can become hyperactive during stressful situations. This may cause the intestines to become more active and contract, or squeeze, more frequently. Similar to fibromyalgia, some research has also shown that IBS can occur following a stressful life event, or may result from an impairment in the body’s ability to appropriately process pain. In addition, certain dietary factors may trigger IBS, including sensitivity to gluten, all-wheat products, dairy, or yeast.
IBS is very common, affecting approximately one out of every six people in the U.S. Although it can occur at any age, IBS typically starts in the teens and early adulthood. Women are affected twice as often as men. The symptoms of IBS can range from mild to severe and vary among individuals. The primary symptoms of IBS include abdominal pain, fullness, gas, and bloating. These symptoms tend to be relieved or reduced following a bowel movement, or occur when there is a change in the frequency of bowel movements. Constipation and diarrhea are common, and people may switch between one or the other or be predominantly affected by only one. All symptoms of IBS may wax or wane, while for some people they are constant. IBS may also cause some individuals to lose their appetite.
Diagnosis and Treatment of IBS
Similar to the diagnosis of fibromyalgia, the diagnosis of IBS is usually made based on symptoms, though sometimes doctors may need to run tests to exclude other diagnoses, including lactose deficiency, anemia, and intestinal infection. Treatment is geared toward relieving the symptoms of IBS, and includes a combination of lifestyle changes, dietary modifications, and certain prescription medications. Lifestyle changes may include regular exercise and increased sleep to reduce anxiety. Diet recommendations will vary from person to person based on individual circumstances and needs, but generally include avoiding stimulants such as caffeine, eating small meals (as opposed to large portion sizes), and increasing the amount of fiber in the diet to relieve constipation. Certain medications may be of benefit to help control intestinal muscle spasms if they are taken prior to eating a meal, while others may be used to treat constipation, diarrhea, intestinal pain, as well as anxiety and depression.
A number of natural therapies have been researched as treatments for IBS and several have demonstrated possible effectiveness. Bifidobacteria and lactobacillus have both been shown to have possible beneficial effects (O’Mahoney et al., 2005; Kim et al., 2003; Halpern et al., 1996) as has blond psyllium (Fox et al., 1981; Jalihal et al., 1990; Prior & Whorwell, 1987; Kumar et al., 1987; Misra et al., 1989). Guar gum and wheat bran were both investigated and shown to be possibly effective, with guar gum showing slightly more benefit (Parisi et al., 2002). Peppermint oil capsules have also been investigated and the findings are mixed; a number of studies have shown effectiveness (Liu et al., 1997; Kline et al., 2001; Dew et al., 1984; Rees et al., 1979; Grigolet & Grigolet, 2005; Capello et al., 2007) whereas others have not (Nash et al., 1986; Lawson et al., 1988).
Overlap between IBS and Fibromyalgia
It has been estimated that as many as two-thirds of all IBS patients have fibromyalgia, and as many as 70% of fibromyalgia patients may also have IBS. These statistics differ greatly from the corresponding rates in the general population, where only 10%-15% of individuals are estimated to have IBS. It is unknown if the two conditions are related symptomatically or causally, or if their frequent co-occurrence is merely a coincidence. Although the symptoms of IBS are limited to the gastrointestinal system and the symptoms of fibromyalgia are predominantly musculoskeletal in nature, there are some similarities and overlaps between the two conditions.
Both conditions are considered functional in nature and neither has a definitively known cause. Underlying genetic or environmental factors – working either alone or in combination – may be the common thread. They both occur most often in women and frequently do so following a stressful life event. In addition, certain prescription medications and cognitive behavioral therapy (a type of psychological therapy that helps patients understand how their thoughts and feelings affect behavior) can be effective means of treatment for both conditions. Individuals with either condition also have increased sensitivity to pain.
Living with IBS and Fibromyalgia
Life can be quite difficult for those individuals who have both conditions. People with both IBS and fibromyalgia tend to suffer from more severe symptoms and poorer overall quality of life than those who suffer from only one of the conditions. Furthermore, the presence of IBS appears to make fibromyalgia pain and fatigue worse. Conversely, the presence of fibromyalgia tends to increase the pain and severity of IBS symptoms. Many individuals with fibromyalgia are already severely limited at times due to the impact their disease has on their bodies; when IBS is an additional factor in the equation, individuals with fibromyalgia can suffer from even greater impairment, decreased mobility, increased anxiety and depression, and social isolation. These associated conditions appear to frequently feed off of each other.
Scientific Research Regarding IBS and Fibromyalgia
A number of studies have been conducted in an effort to better understand the relationship between, and coexistence of, fibromyalgia and IBS. Studies have looked at the common occurrence of increased pain sensitivity among the two conditions, as well as the overlapping symptoms and demographics (such as depression, fatigue, and predominance in women).
A 2001 study by Lubrano et al. evaluated 130 patients with IBS and found that 20% also had fibromyalgia. The researchers also found a significant association between the presence of fibromyalgia and the severity of IBS (i.e., those patients with both IBS and fibromyalgia had more profound IBS symptoms). It is important to note, however, that some studies have conflicted these findings and observed no differences in abdominal pain sensitivity between fibromyalgia patients with IBS and those with just a diagnosis of IBS (Chang et al. 2000; Chang et al 2003).
A 1999 study by Sperber et al. evaluated 79 IBS patients and 72 control subjects, as well as 100 fibromyalgia patients to determine the prevalence of fibromyalgia in IBS and vice versa, as well as the implications of having both conditions on individuals’ quality of life measures. The researchers found that 79 IBS patients (31.6%) had fibromyalgia, versus only 3 (4.2%) of the healthy control subjects. They also found that overall well-being, measures of sleep disturbance, anxiety, physical function, and quality of life were all worse among those IBS patients who also had fibromyalgia.
Although findings are mixed, the predominant observations in the medical literature point to the understanding that having both fibromyalgia and IBS leads to greater overall pain, decreased physical functioning, and poorer overall quality of life. More research is clearly needed, however, and should focus on investigating possible common causes, improved diagnosis and differentiation of both conditions, as well as improved treatment strategies for individuals who suffer from both IBS and fibromyalgia.