Endometriosis and Comorbidities: IBS
Endometriosis is a condition that can cause cumulative and far-reaching effects throughout the patient’s body. In addition, it has been noted in several studies that due to the neurological and immunological nature of the disease, there is a high chance of comorbidity with other chronic conditions, especially those that affect the thoracic and abdominal organs. A prominent example of comorbidities include a strong clinically-proven link to Irritable Bowel Syndrome (or IBS). Endometriosis is found to be prevalent in between 0.7-8.6 percent of the world’s population, while IBS has an average global prevalence of 5.7%, with concentrations dependent on region.
Although one could reasonably say that this overlap is simply due to probability, research suggests otherwise. An epidemiological study by Nabi et al. (2021) has uncovered that participants with endometriosis had around a 300% higher likelihood of also suffering from irritable bowel syndrome. So far, researchers have proposed several theories as to why this heightened risk exists.
The foremost theory is that an immune system turned hyper-aware due to endometrial growths can send out mast cells to needlessly attack digestive tissues and beneficial gut bacteria, leading to deficits in a healthy intestinal cycle. Another theory revolves around the genetic and epigenetic nature of both conditions, suggesting that deficiencies in one genome cause similar deficiencies in the other. Thirdly, the “leaky gut syndrome” theory for IBS suggests that an impaired and permeable intestinal barrier can cause pathogens to “leak” through tissues, leading to heightened inflammation and immune response. Keeping this concept in mind, a “leaky gut” could also theoretically allow for the transmission of endometrial cells throughout the abdominal cavity.
Furthermore, there can be a significant overlap between the symptoms caused by both conditions. This hybridization is especially present in patients with endometriosis of the bowel. As endometriosis causes abdominal pain and irregular bowel movements, it is easy for irritable bowel syndrome to effectively “hide” in plain sight, having caused the same nuisance. A simple method to distinguish between pain caused by the two pathologies is that most endometrial pain is cyclical and revolves around the individual’s menstrual cycle.
However, this key is not universal as a significant number of patients suffer from lowered cyclicality and constant pain and IBS-like symptoms throughout the cycle. Thankfully, almost all endometrial growths in the bowel can be detected through scans performed by expert hands, which can greatly help in the diagnosis of bowel endometriosis. Therefore, it is especially important for patients suffering from both conditions to get regular screening and to report any changes in their conditions to their main care provider.
Sources:
https://www.frontiersin.org/articles/10.3389/fmed.2022.914356/full
https://www.chelwest.nhs.uk/your-visit/patient-leaflets/medicine-services/bowel-endometriosis
https://pubmed.ncbi.nlm.nih.gov/32949284/
https://academic.oup.com/humrep/article-abstract/37/9/2186/6609839?redirectedFrom=fulltext&login=false (Endometriosis and irritable bowel syndrome: similarities and differences in the spectrum of comorbidities)
https://www.sciencedirect.com/science/article/pii/S172649011630123X