Endometriosis and irritable bowel syndrome: a systematic review and meta-analysis

Human Leukocyte Antigen Haplotypes Predisposing to Celiac Disease in Patients With Endometriosis

PROBLEM

Immunological abnormalities are well recognized in the pathogenesis of endometriosis and the co-existence of endometriosis with inflammatory bowel disease (IBD) and celiac disease (CD), along with other systemic immune disorders, is clinically relevant. Recent genetic studies revealed some shared genetic traits associated with the co-occurrence of endometriosis with different gastrointestinal or autoimmune disorders, highlighting common biological pathways. Since class II human leukocyte antigen (HLA) genes, HLA-DQ2 and -DQ8, show the strongest and best-characterized genetic susceptibility for CD, the present study aims to explore the presence of these haplotypes in non-celiac patients with endometriosis.

METHOD OF STUDY

A group of patients with endometriosis (n = 126) participated in the study and were compared to healthy women (n = 379), as controls. Subjects who were diagnosed with CD or who tested positive for CD antibodies were excluded. All patients and controls were genotyped for HLA haplotypes predisposing to CD (DQ2, DQ8). In the group of endometriosis patients who tested positive for DQ2 and/or DQ8, symptoms were also investigated.

RESULTS

At least one of the HLA-DQ2 and -DQ8 genotypes was detected in 43.3% of non-celiac endometriosis patients (OR: 1.82, 95% CI: 1.11-2.81), whereas 29.5% (p < 0.01) of healthy women presented HLA haplotypes predisposing to CD. In endometriosis patients, no significant difference was shown between positive and negative in terms of endometriosis phenotype, or gynecological, and non-gynecological symptoms.

CONCLUSIONS

Our data revealed a significantly greater prevalence of predisposing haplotypes for CD in non-celiac patients with endometriosisthan in healthy subjects, suggesting that a common genetic background may explain the co-occurrence of endometriosis and CD.

Impact of deep or ovarian endometriosis on pelvic pain and quality of life: prospective cross-sectional ultrasound study

OBJECTIVE

To assess whether premenopausal women diagnosed with deep or ovarian endometriosis on transvaginal sonography (TVS) were more likely to suffer from dyspareunia and pelvic pain symptoms, and have a lower quality of life, compared to women without sonographically diagnosed deep or ovarian endometriosis.

METHODS

This was a prospective, cross-sectional study carried out between February 2019 and October 2020 at the general gynecology clinic at University College London Hospital, London, UK. All premenopausal women aged 18-50 years, who were examined consecutively by a single experienced examiner and underwent a detailed TVS scan, were eligible for inclusion. Pregnant women and those who had received a previous diagnosis of endometriosis or who had experienced a hysterectomy or unilateral/bilateral oophorectomy were excluded. Sonographic findings consistent with deep or ovarian endometriosis were noted. All women completed the British Society of Gynaecological Endoscopy pelvic pain questionnaire. The primary outcome was to determine whether women with sonographic evidence of endometriosis were more likely to experience moderate-to-severe levels of dyspareunia (score of ≥ 4 on an 11-point numerical rating scale (NRS)). Secondary outcomes included assessing moderate-to-severe levels of other pelvic pain symptoms (NRS score of ≥ 4), bowel symptoms (score of ≥ 2 on a 5-point Likert scale) and quality of life, which was measured using the EuroQol-5D-3L (EQ-5D) questionnaire. The number of women with pain scores ≥ 4 and bowel scores ≥ 2, as well as the mean EQ-5D scores, were compared between the group with and that without sonographic evidence of endometriosis using logistic regression analysis, and multivariable analysis was used to adjust for demographic and clinical variables.

RESULTS

A total of 514 women were included in the final study population, of whom 146 (28.4%) were diagnosed with deep or ovarian endometriosis on TVS. On multivariable analysis, the presence of moderate-to-severe dyspareunia was not found to be associated with endometriosis. Moderate-to-severe dyspareunia was significantly associated with lower age (odds ratio (OR), 0.70 (95% CI, 0.56-0.89); P = 0.003) and a history of migraine (OR, 3.52 (95% CI, 1.42-8.77); P = 0.007), and it occurred significantly less frequently in women with non-endometriotic ovarian cysts (OR, 0.47 (95% CI, 0.28-0.78); P = 0.003). There was also a trend towards a positive association between anxiety/depression and moderate-to-severe dyspareunia (OR, 1.94 (95% CI, 0.93-4.03); P = 0.08). Following multivariable analysis, the only symptoms that were significantly more common in women with endometriosis compared to those without were menstrual dyschezia (OR, 2.44 (95% CI, 1.59-3.78); P < 0.001) and difficulty emptying the bladder (OR, 2.56 (95% CI, 1.52-4.31); P < 0.001). Although not reaching statistical significance on multivariable analysis, dysmenorrhea (OR, 1.72 (95% CI, 0.92-3.20); P = 0.09) and lower EQ-5D score (mean ± SD, 0.67 ± 0.33 vs 0.72 ± 0.28; P = 0.06) also occurred more frequently in women with sonographic evidence of endometriosis.

CONCLUSIONS

The majority of pelvic pain symptoms did not differ significantly between women with and those without sonographic evidence of endometriosis, indicating that endometriosis may not always be the source of pelvic pain, even if present. This highlights the need to rule out other causes of pain in symptomatic endometriosis patients before considering surgical procedures, and to provide appropriate patient counseling. © 2024 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Comprehensive Management of Bowel Endometriosis: Surgical Techniques, Outcomes, and Best Practices

Bowel endometriosis is a complex condition predominantly impacting women in their reproductive years, which may lead to chronic pain, gastrointestinal symptoms, and infertility. This review highlights current approaches to the diagnosis and management of bowel endometriosis, emphasizing a multidisciplinary strategy. Diagnostic methods include detailed patient history, physical examination, and imaging techniques like transvaginal ultrasound (TVUS) and magnetic resonance imaging (MRI), which aid in preoperative planning. Management options range from hormonal therapies for symptom relief to minimally invasive surgical techniques. Surgical interventions, categorized as shaving excision, disc excision, or segmental resection, depend on factors such as lesion size, location, and depth. Shaving excision is preferred for its minimal invasiveness and lower complication rates, while segmental resection is reserved for severe cases. This review also explores nerve-sparing strategies to reduce surgical morbidity, particularly for deep infiltrative cases close to the rectal bulb, anal verge, and rectosigmoid colon. A structured, evidence-based approach is recommended, prioritizing conservative surgery to avoid complications and preserve fertility as much as possible. Comprehensive management of bowel endometriosis requires expertise from both gynecologic and gastrointestinal specialists, aiming to improve patient outcomes while minimizing long-term morbidity.

Hospitalisations and length of stays in women with endometriosis: a data linkage prospective cohort study

Background

Women with endometriosis have more hospitalisations compared to those without the condition. However, no longitudinal study has examined hospital admission rates and lengths of stay before and after diagnosis. We examined all-cause hospital admissions and lengths of stay among women with, versus without, endometriosis, and before, versus after, diagnosis.

Methods

This study included 13,501 women of reproductive age, born in 1973-78. The Australian Longitudinal Study on Women's Health survey data linked to administrative health records was used to identify women with endometriosis. Hospital admission rates and length of stays were examined using hospital records of patients admitted up to 2022. Analysis was conducted using mixed-effects zero-inflated negative binomial models.

Findings

Women with endometriosis were more likely to be admitted to hospitals compared to those without the condition, with an adjusted incidence rate ratio (IRR) of 2.11 (95% CI: 1.83-2.43) for admissions per year. However, they had shorter hospital stays (IRR: 0.90; 0.81-0.99) for days per year and were more often discharged on the same day (odds ratio: 1.27; 1.20-1.33). Post-diagnosis, women experienced more hospitalisations and more days in hospital compared to their pre-diagnosis (IRR: 1.52; 1.22-1.88) and (IRR: 1.81; 1.53-2.14), respectively. Consistent findings were found for women with surgically confirmed or clinically suspected endometriosis.

Interpretation

The higher number of hospitalisations among women with endometriosis, compared to those without, highlights the substantial burden of the condition on healthcare utilisation. The persistent frequent hospitalisations and longer stays post-diagnosis indicate recurrent endometriosis, posing significant management challenges.

Funding

The Australian Longitudinal Study on Women's Health is funded by the Australian Government Department of Health and Aged Care. GDM and GWM are Australian National Health and Medical Research Council Leadership Fellows (GNT2009577 and GNT1177194).

Dietary and Nutritional Interventions for the Management of Endometriosis

Endometriosis is a chronic, complex, systemic inflammatory condition that impacts approximately 190 million girls and women worldwide, significantly impacting their quality of life. The effective management of endometriosis requires a multi-disciplinary and holistic approach, one that includes surgical and medical management, such as a laparoscopy and a chronic medical management plan, as well as dietary, nutritional, and lifestyle adjunct interventions, such as pelvic pain physiotherapy and acupuncture. There is growing evidence to support the role of dietary and nutritional interventions in the adjunct management of endometriosis-related pain and gastrointestinal symptoms. However, the implementation of these interventions is often not regulated, as patients with endometriosis often adopt self-management strategies. Diet and nutrition can modulate key players integral to the pathophysiology of endometriosis, such as, but not limited to, inflammation, estrogen, and the microbiome. However, it is unclear as to whether diet plays a role in the prevention or the onset of endometriosis. In this review, we discuss three key players in the pathogenesis of endometriosis-inflammation, estrogen, and the microbiome-and we summarize how diet and nutrition can influence their mechanisms, and consequently, the progression and manifestation of endometriosis. There is a major need for evidence-based, non-invasive adjunct management of this debilitating disease, and diet and nutritional interventions may be suitable.

Prevalence of irritable bowel syndrome in endometriosis patients: A cross-sectional study

Background

Despite its prevalence, limited research has explored the direct correlation between irritable bowel syndrome (IBS) and endometriosis, particularly in regions like Saudi Arabia. This study aimed to bridge this gap by investigating the prevalence of IBS among endometriosis patients and identifying associated risk factors.

Materials and Methods

The study conducted a cross-sectional analysis, it was done at King Abdulaziz University Hospital, Jeddah. From September to December 2023. Women who were diagnosed with endometriosis and aged above 18 years old were included.

Results

Our study revealed that 47.8% of endometriosis patients had previously been diagnosed with IBS. Interestingly, Saudi patients exhibited a significantly higher prevalence of IBS compared to non-Saudi individuals. While no substantial link emerged between IBS prevalence and other demographic or endometriosis-related factors, patients with chronic digestive conditions like food intolerance, esophageal reflux, and inflammatory colon diseases showed a higher likelihood of IBS.

Conclusions

This study underscores a substantial association between IBS and endometriosis, urging healthcare providers to consider IBS as a potential comorbidity in affected patients. The findings stress the importance of holistic assessments and awareness regarding overlapping symptoms and risk factors. Further research is encouraged to unveil underlying mechanisms and devise optimal management strategies for individuals grappling with both conditions.

Endometriosis Is Associated With Higher Healthcare Utilization and Upper Gastrointestinal Symptoms

Endometriosis is a chronic inflammatory disease affecting 10%-15% of women, with symptoms including abdominopelvic pain, dysmenorrhea, and menorrhagia. Up to 90% experience gastrointestinal (GI) symptoms including constipation, bloating, and nausea/vomiting.1 Females with endometriosis are at 3-5 times greater risk of developing IBS than healthy women,2,3 with rates of IBS as high as 52%.4 Another study demonstrated 37% of those with IBS also had endometriosis, much higher than the typical prevalence of endometriosis.5 Patients with IBS and endometriosis experience lower pain thresholds and more painful menstrual cycles than those with either condition alone. This amplification of pain experiences can increase health care utilization and decrease quality of life.

Evaluating the safety of high-intensity focused ultrasound treatment for rectal endometriosis: results from a French prospective multicentre study including 60 patients

STUDY QUESTION

Is increasing the intensity of high-intensity focused ultrasound (HIFU) by 30% in the treatment of rectal endometriosis a safe procedure?

SUMMARY ANSWER

This study demonstrates the safety of a 30% increase in the intensity of HIFU in the treatment of rectal endometriosis, with no Clavien-Dindo Grade III complications overall, and namely no rectovaginal fistulae.

WHAT IS KNOWN ALREADY

A feasibility study including 20 patients with rectal endometriosis demonstrated, with no severe complications, a significant improvement in digestive disorders, dysmenorrhoea, dyspareunia, and health status, although the volume of the endometriosis nodule did not appear to be reduced.

STUDY DESIGN, SIZE, DURATION

A prospective multicentre cohort study was conducted between 2020 and 2022 with 60 patients with symptomatic rectal endometriosis. Following the failure of medical treatment, HIFU treatment was offered as an alternative to surgery.

PARTICIPANTS/MATERIALS, SETTING, METHODS

As the main objective of this study was to examine safety, all adverse events observed during the 6 months of follow-up were analysed and graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) and Clavien-Dindo classifications. Secondary objectives included evaluating the evolution of symptoms using validated questionnaires: gynaecological and digestive pain symptoms with a visual analogue scale, health status with the Medical Outcomes Study 36-item Short Form (SF-36) questionnaire, average post-operative daily pain level, and analgesic medication required in the 10 days following treatment. MRI was also performed at Day 1 to detect early complications. Finally, we performed a blinded MRI review of the evolution of the nodule at 6 months post-treatment.

MAIN RESULTS AND THE ROLE OF CHANCE

The procedure was performed under spinal anaesthesia for 30% of the patients. The median duration of treatment was 32 min. Fifty-five patients left the hospital on Day 1. MRI scans performed on Day 1 did not highlight any early-onset post-operative complication. Using the Clavien-Dindo classification, we listed 56.7% Grade I events, 3.4% Grade II events, and no events Grade III or higher. At 1, 3, and 6 months, all gynaecologic, digestive and general symptoms, as well as health status, had significantly improved. The evolution of the nodule was also significant (P < 0.001) with a 28% decrease in volume.

LIMITATIONS, REASONS FOR CAUTION

The main objective was safety and not effectiveness. The study was not randomized and there was no control group.

WIDER IMPLICATIONS OF THE FINDINGS

HIFU treatment for rectal endometriosis results in an improvement of symptoms with low morbidity; as such, for selected patients, it could be a valuable alternative to surgical approaches following the failure of medical treatment.

STUDY FUNDING/COMPETING INTEREST(S)

The study was funded by the company EDAP TMS. Professors Dubernard and Rousset are consultants for EDAP TMS. Dubernard received travel support from EDAP-TMS. Dr F. Chavrier received industrial grants from EDAP-TMS. He has developed a device for generating focused ultrasonic waves with reduced treatment time. This device has been patented by EDAP-TMS. Dr Lafon received industrial grants from EDAP-TMS; he declares that EDAP-TMS provided funding directly to INSERM to support a young researcher chair in therapeutic ultrasound, which is unrelated to the current study.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov identifier NCT04494568.

A gluten-free diet for endometriosis patients lacks evidence to recommend it

Endometriosis is an estrogen-dependent chronic disease characterized by the presence of endometriumlike tissue outside the uterus and is often associated with symptoms, such as dysmenorrhea, dysuria, dyschezia, chronic pelvic pain, and infertility. Moreover, women diagnosed with endometriosis can report gastrointestinal symptoms, including bloating, constipation or diarrhea, and abdominal cramping, which can be associated with irritable bowel syndrome and can result in the misdiagnosis of endometriosis as irritable bowel syndrome at first. Treatment usually involves hormonal therapy, pain management, surgery, and/or assisted reproductive techniques in case of infertility. Nonetheless, these treatment methods can be insufficient for alleviating symptoms or can have unacceptable side effects, leading to noncompliance. Therefore, women often apply self-management strategies, including dietary interventions. One of the diets frequently suggested as a tool to manage endometriosis-related symptoms on social media and patient forums is a gluten-free diet. Although a gluten-free diet has been proven effective in managing nonceliac wheat sensitivity or celiac disease, its effectiveness in endometriosis remains uncertain. The Nurses' Health Study II found it unlikely that gluten intake was a strong factor in endometriosis etiology and symptomatology. To the best of our knowledge, the most frequently cited and sole published intervention study on the efficacy of a gluten-free diet for endometriosis has several important limiting factors, including the absence of a control group. In addition, gluten consumption is highly susceptible to a placebo effect and a nocebo effect, where women might experience symptom relief after eliminating gluten and return of symptoms after they consume gluten again, solely because they believe that gluten is bad for them. Despite the inverse association between body mass index and endometriosis and between a gluten-free diet and increased body mass index, this is an association, and no causality was proven. In addition, other factors should be taken into consideration. Of note, a gluten-free diet is expensive, has limited availability, and has a significant effect on quality of life. Moreover, without proper dietary guidance, it may adversely affect the gastrointestinal microbiome. Therefore, scientifically substantiated advice regarding the use of a gluten-free diet for endometriosis-related symptoms is currently not available, and a gluten-free diet should be discouraged unless there is an additional diagnosis of nonceliac wheat sensitivity or celiac disease.

Unraveling the relationship between gut microbiota and site-specific endometriosis: a Mendelian randomization analysis

Background

Although numerous studies have illustrated the connection between gut microbiota and endometriosis, a conspicuous gap exists in research focusing on the pathogenesis of endometriosis at various sites and its linkage with infertility.

Methods

In this study, we used a two-sample Mendelian randomization analysis to investigate the effect of gut microbiota on the development of endometriosis in different regions, including the uterus, ovary, fallopian tube, pelvic peritoneum, vagina, and rectovaginal septum, as well as the intestine. Additionally, we explored the correlation between gut microbiota and endometriosis-induced infertility. Genetic associations with gut microbes were obtained from genome-wide association study (GWAS) datasets provided by the MiBioGen consortium, whereas endometriosis-related GWAS data were sourced from the FinnGen dataset. In our analysis, single-nucleotide polymorphisms were used as instrumental variables, with the primary estimation of the causal effect performed via the inverse variance weighting method. Our sensitivity analyses incorporated heterogeneity tests, pleiotropy tests, and the leave-one-out method.

Results

We identified associations at the genus level between four bacterial communities and endometriosis. Subsequently, several associations between the gut microbiota and various subtypes of endometriosis at different anatomical sites were recognized. Specifically, three genera were linked with ovarian endometriosis, six genera were associated with tubal endometriosis, four genera showed links with pelvic peritoneum endometriosis, five genera were connected with vaginal and rectovaginal septum endometriosis, and seven genera demonstrated linkages with intestinal endometriosis. Additionally, one genus was associated with adenomyosis, and three genera exhibited associations with endometriosis-induced infertility.

Conclusion

Our study elucidates associations between gut microbiota and site-specific endometriosis, thereby augmenting our understanding of the pathophysiology of endometriosis. Moreover, our findings pave the way for potential therapeutic strategies targeting gut microbiota for individuals grappling with endometriosis-related infertility.

An artificial intelligence approach for investigating multifactorial pain-related features of endometriosis

Endometriosis is a debilitating, chronic disease that is estimated to affect 11% of reproductive-age women. Diagnosis of endometriosis is difficult with diagnostic delays of up to 12 years reported. These delays can negatively impact health and quality of life. Vague, nonspecific symptoms, like pain, with multiple differential diagnoses contribute to the difficulty of diagnosis. By investigating previously imprecise symptoms of pain, we sought to clarify distinct pain symptoms indicative of endometriosis, using an artificial intelligence-based approach. We used data from 473 women undergoing laparoscopy or laparotomy for a variety of surgical indications. Multiple anatomical pain locations were clustered based on the associations across samples to increase the power in the probability calculations. A Bayesian network was developed using pain-related features, subfertility, and diagnoses. Univariable and multivariable analyses were performed by querying the network for the relative risk of a postoperative diagnosis, given the presence of different symptoms. Performance and sensitivity analyses demonstrated the advantages of Bayesian network analysis over traditional statistical techniques. Clustering grouped the 155 anatomical sites of pain into 15 pain locations. After pruning, the final Bayesian network included 18 nodes. The presence of any pain-related feature increased the relative risk of endometriosis (p-value < 0.001). The constellation of chronic pelvic pain, subfertility, and dyspareunia resulted in the greatest increase in the relative risk of endometriosis. The performance and sensitivity analyses demonstrated that the Bayesian network could identify and analyze more significant associations with endometriosis than traditional statistical techniques. Pelvic pain, frequently associated with endometriosis, is a common and vague symptom. Our Bayesian network for the study of pain-related features of endometriosis revealed specific pain locations and pain types that potentially forecast the diagnosis of endometriosis.

Comprehensive endometriosis care: a modern multimodal approach for the treatment of pelvic pain and endometriosis

Endometriosis is a prevalent gynecological disease, leading to chronic pain and inflammation, affecting 1 in 10 individuals presumed female at birth. The diagnostic journey is often arduous, marked by neglect of the right diagnosis and prolonged wait times, significantly compromising the quality of life among those affected. This review provides a nuanced exploration of endometriosis-associated pain management, encompassing medical, surgical, and holistic approaches, all guided by accurate and refined diagnostics. Our paramount goal is to empower physicians as key figures in confronting this intricate challenge with a patient-centric approach, ultimately aiming to improve treatment and quality of life. Acknowledging each patient's unique needs, we emphasize the importance of tailoring a spectrum of options informed by current literature and insights gleaned from our experience in a high-volume tertiary endometriosis center. It is imperative to recognize endometriosis as a complex and chronic disease, often occurring with co-morbid conditions and nuanced complexities, necessitating a long-term personalized multimodal approach for each case. In addition, incorporating principles such as patient autonomy, profound respect for diverse experiences, and practical education on treatment choices is pivotal in enhancing treatment outcomes and overall patient satisfaction.

Evidence of shared genetic factors in the etiology of gastrointestinal disorders and endometriosis and clinical implications for disease management

In clinical practice, the co-existence of endometriosis and gastrointestinal symptoms is often observed. Using large-scale datasets, we report a genetic correlation between endometriosis and irritable bowel syndrome (IBS), peptic ulcer disease (PUD), gastro-esophageal reflux disease (GORD), and a combined GORD/PUD medicated (GPM) phenotype. Mendelian randomization analyses support a causal relationship between genetic predisposition to endometriosis and IBS and GPM. Identification of shared risk loci highlights biological pathways that may contribute to the pathogenesis of both diseases, including estrogen regulation and inflammation, and potential therapeutic drug targets (CCKBR; PDE4B). Higher use of IBS, GORD, and PUD medications in women with endometriosis and higher use of hormone therapies in women with IBS, GORD, and PUD, support the co-occurrence of these conditions and highlight the potential for drug repositioning and drug contraindications. Our results provide evidence of shared disease etiology and have important clinical implications for diagnostic and treatment decisions for both diseases.

Insights from Mendelian randomization and genetic correlation analyses into the relationship between endometriosis and its comorbidities

BACKGROUND

Endometriosis remains a poorly understood disease, despite its high prevalence and debilitating symptoms. The overlap in symptoms and the increased risk of multiple other traits in women with endometriosis is becoming increasingly apparent through epidemiological data. Genetic studies offer a method of investigating these comorbid relationships through the assessment of causal relationships with Mendelian randomization (MR), as well as identification of shared genetic variants and genes involved across traits. This has the capacity to identify risk factors for endometriosis as well as provide insight into the aetiology of disease.

OBJECTIVE AND RATIONALE

We aim to review the current literature assessing the relationship between endometriosis and other traits using genomic data, primarily through the methods of MR and genetic correlation. We critically examine the limitations of these studies in accordance with the assumptions of the utilized methods.

SEARCH METHODS

The PubMed database was used to search for peer-reviewed original research articles using the terms 'Mendelian randomization endometriosis' and '"genetic correlation" endometriosis'. Additionally, a Google Scholar search using the terms '"endometriosis" "mendelian randomization" "genetic correlation"' was performed. All relevant publications (n = 21) published up until 7 October 2022 were included in this review. Upon compilation of all traits with published MR and/or genetic correlation with endometriosis, additional epidemiological and genetic information on their comorbidity with endometriosis was sourced by searching for the trait in conjunction with 'endometriosis' on Google Scholar.

OUTCOMES

The association between endometriosis and multiple pain, gynaecological, cancer, inflammatory, gastrointestinal, psychological, and anthropometric traits has been assessed using MR analysis and genetic correlation analysis. Genetic correlation analyses provide evidence that genetic factors contributing to endometriosis are shared with multiple traits: migraine, uterine fibroids, subtypes of ovarian cancer, melanoma, asthma, gastro-oesophageal reflux disease, gastritis/duodenitis, and depression, suggesting the involvement of multiple biological mechanisms in endometriosis. The assessment of causality with MR has revealed several potential causes (e.g. depression) and outcomes (e.g. ovarian cancer and uterine fibroids) of a genetic predisposition to endometriosis; however, interpretation of these results requires consideration of potential violations of the MR assumptions.

WIDER IMPLICATIONS

Genomic studies have demonstrated that there is a molecular basis for the co-occurrence of endometriosis with other traits. Dissection of this overlap has identified shared genes and pathways, which provide insight into the biology of endometriosis. Thoughtful MR studies are necessary to ascertain causality of the comorbidities of endometriosis. Given the significant diagnostic delay of endometriosis of 7-11 years, determining risk factors is necessary to aid diagnosis and reduce the disease burden. Identification of traits for which endometriosis is a risk factor is important for holistic treatment and counselling of the patient. The use of genomic data to disentangle the overlap of endometriosis with other traits has provided insights into the aetiology of endometriosis.

Diet associations in endometriosis: a critical narrative assessment with special reference to gluten

Endometriosis is characterized by the presence of endometrium-like tissue outside the uterus. The etiology remains largely unknown. Despite adequate treatment, patients can still experience symptoms or side effects resulting in therapy incompliance and in self-management strategies such as dietary measures is increasing. A gluten free diet is thought to be contributory in reducing endometriosis-related pain, thereby optimizing quality of life. However, data is conflicting and currently provides no evidence for causality. This narrative review aims to put the effect of dietary self-management strategies on endometriosis in a balanced perspective, especially the effect of gluten and a gluten free diet. Several studies have found a strong overlap in symptoms, metabolic and immune responses associated with endometriosis and those associated with celiac disease, ulcerative colitis, Crohn's disease, irritable bowel syndrome and non-celiac wheat sensitivity. However, it remains unclear whether these diseases and/or disorders are causal to an increased risk of endometriosis. Some studies have found a positive effect on the risk of endometriosis, endometriosis-related symptoms and quality of life (QoL) when women either avoided certain nutrients or foods, or applied a specific nutrient supplementation. This includes the avoidance of red meat, an increasing intake of foods rich in anti-oxidants, omega-3, micronutrients and dietary fibers (e.g., fruit, vegetables) and the appliance of a gluten free diet. However, data from the available studies were generally graded of low quality and it was noted that placebo and/or nocebo effects influenced the reported positive effects. In addition, such effects were no longer seen when adjusting for confounders such as overweight, when a translation was made from in vitro to in vivo, or when the nutrients were not supplemented as isolated sources but as part of a mixed daily diet. Finally, some studies showed that long-term adherence to a gluten free diet is often associated with an impaired diet quality and nutrient intake, leading to negative health outcomes and reduced QoL. Concluding, scientific evidence on the efficacy of dietary interventions on well-defined clinical endpoints of endometriosis is lacking and recommending a gluten free diet to women solely diagnosed with endometriosis should therefore not be advised.

Self-managed dietary changes and functional gut symptoms in endometriosis: A qualitative interview study

Objective

Endometriosis is a chronic gynaecological condition, often causing gastrointestinal symptoms and misdiagnosed as irritable bowel syndrome (IBS). Endometriosis guidelines do not formally endorse dietary changes and little is known about how they are self-managed. The objective of this study is to understand nutritional practices and management of gut symptoms in people with endometriosis.

Study design

Participants were recruited as part of a larger survey study via endometriosis support groups on social media. Eligibility criteria were: a self-reported physician-led diagnosis of endometriosis, over 18 years old and residing in the United Kingdom (UK). Semi-structured interviews were undertaken virtually via Zoom using a predefined interview guide. All interviews were transcribed and analysed using thematic analysis.

Results

10 people with endometriosis were interviewed. All had made individual dietary changes to manage their gut-related endometriosis symptoms. Dietary changes were made based on advice from social media support, books, websites or professionals other than dietitians. Changes included the restriction and exclusion of multiple essential food groups, including dairy, grains (primarily gluten), vegetables, fruits, and animal products. These changes impacted participants' weight, nutritional status and relationship with food. Four strong themes were identified: 1) impact of pain 2) severe and unpredictable gut symptoms 3) dietary changes and their impact 4) seeking support for dietetic intervention. A common thread underlying and linking these four main themes was the feeling of being dismissed, care being delayed and lack of support. Overall the long delay waiting for a diagnosis, surgery and, at times, the re-occurrence of symptoms post-surgery led to unsupported trial and error with modifiable lifestyle factors, including diet.

Conclusion

Overall, participants demonstrated some patterns of restrictive eating behaviour and wanted more professional support to help manage their endometriosis-related gut symptoms. This highlights the need for dietitians to be involved in endometriosis care to help alleviate gut symptoms, whilst ensuring nutritional adequacy and offering weight management support where required.

Genomic characterisation of the overlap of endometriosis with 76 comorbidities identifies pleiotropic and causal mechanisms underlying disease risk

Comorbid conditions can be driven by underlying pleiotropic and causal mechanisms that can provide insights into shared molecular and biological processes contributing to disease risk. Endometriosis is a chronic condition affecting one in nine women of reproductive age and poses many challenges including lengthy diagnostic delays and limited treatment efficacy owing to poor understanding of disease aetiology. To shed light on the underlying biological mechanisms and to identify potential risk factors, we examine the epidemiological and genomic relationship between endometriosis and its comorbidities. In the UK Biobank 292 ICD10 codes were epidemiologically correlated with endometriosis diagnosis, including gynaecological, immune, infection, pain, psychiatric, cancer, gastrointestinal, urinary, bone and cardiovascular traits. A subset of the identified comorbidities (n = 76) underwent follow-up genetic analysis. Whilst Mendelian randomisation suggested causality was not responsible for most comorbid relationships, 22 traits were genetically correlated with endometriosis, including pain, gynaecological and gastrointestinal traits, suggestive of a shared genetic background. Pleiotropic genetic variants and genes were identified using gene-based and colocalisation analysis. Shared genetic risk factors and potential target genes suggest a diverse collection of biological systems are involved in these comorbid relationships including coagulation factors, development of the female reproductive tract and cell proliferation. These findings highlight the diversity of traits with epidemiological and genomic overlap with endometriosis and implicate a key role for pleiotropy in the comorbid relationships.

Microbiota in Irritable Bowel Syndrome and Endometriosis: Birds of a Feather Flock Together-A Review

Endometriosis and irritable bowel syndrome (IBS) are chronic conditions affecting up to 10% of the global population, imposing significant burdens on healthcare systems and patient quality of life. Interestingly, around 20% of endometriosis patients also present with symptoms indicative of IBS. The pathogenesis of both these multifactorial conditions remains to be fully elucidated, but connections to gut microbiota are becoming more apparent. Emerging research underscores significant differences in the gut microbiota composition between healthy individuals and those suffering from either endometriosis or IBS. Intestinal dysbiosis appears pivotal in both conditions, exerting an influence via similar mechanisms. It impacts intestinal permeability, triggers inflammatory reactions, and initiates immune responses. Furthermore, it is entwined in a bidirectional relationship with the brain, as part of the gut-brain axis, whereby dysbiosis influences and is influenced by mental health and pain perception. Recent years have witnessed the development of microbiota-focused therapies, such as low FODMAP diets, prebiotics, probiotics, antibiotics, and fecal microbiota transplantation, designed to tackle dysbiosis and relieve symptoms. While promising, these treatments present inconsistent data, highlighting the need for further research. This review explores the evidence of gut dysbiosis in IBS and endometriosis, underscoring the similar role of microbiota in both conditions. A deeper understanding of this common mechanism may enable enhanced diagnostics and therapeutic advancements.

Nutritional practices and dietetic provision in the endometriosis population, with a focus on functional gut symptoms

BACKGROUND

Endometriosis is a common condition causing chronic pain, fatigue and gut symptoms. Research suggests that dietary changes may improve symptoms; however, evidence is lacking. The present study aimed to investigate the nutritional practices and needs of individuals with endometriosis (IWE) and the management of endometriosis by dietitians in the UK, focusing on gut symptoms.

METHODS

Two online questionnaires were distributed via social media: a survey of dietitians working with IWE and functional gut symptoms and a survey of IWE.

RESULTS

All respondents to the dietitian survey (n = 21) used the low fermentable oligosaccharides disaccharides monosaccharides and polyols (FODMAP) diet in IWE, with the majority 69.3% (n = 14), reporting positive adherence and patient benefit. Dietitians recommended more training (85.7%, n = 18) and resources (81%, n = 17) for IWE. Of those who completed the IWE questionnaire (n = 1385), 38.5% (n = 533) had coexisting irritable bowel syndrome. Only 24.1% (n = 330) had satisfactory relief of gut symptoms. The most common symptoms were tiredness, bloating and abdominal pain, experienced by 85.5% (n = 1163), 75.3% (n = 1025) and 67.3% (n = 917), respectively. Some 52.2% (n = 723) had tried dietary modifications to relieve their gut symptoms; 36.7% (n = 500) ate a restricted diet at present; 13.5% (n = 184) experienced recent unintentional weight loss and 29.8% (n = 407) a decreased appetite Some 13.2% (n = 183) had seen a dietitian regarding their gut symptoms. Of those who had not seen a dietitian, 57.7% (n = 693) would find it useful to.

CONCLUSIONS

Gut symptoms and dietary restriction are very common in IWE; however, dietetic input is not. More research on the role of nutrition and dietetics in the management of endometriosis is recommended.

The temporal effect of emotional distress on psychological and physical functioning in endometriosis: A 12-month prospective study

Psychological factors of emotional distress and cognition have an important role in the understanding and management of endometriosis; however, their temporal relationship with key pain variables is not fully understood. This exploratory study sought to establish the temporal relationship between psychological and pain-related factors in a 12-month prospective study of 208 Australian women with endometriosis. Participants, aged 18-50 years and living in Australia, were recruited via social media and completed baseline (May 2019) and 12-month follow-up (June 2020) surveys. Participants who reported a diagnosis of endometriosis and menses in the past 12 months were included in the study. Structural equation modelling was used to determine the temporal effects of psychological and pain-related factors in endometriosis. In a covariate-adjusted model, baseline emotional distress was the only variable to predict pain catastrophizing (β = .24, p < .01), functional pain disability (β = .16, p < .05) and concomitant emotional distress (β = .55, p < .001) 12 months later, adjusting for age and chronic illness. Women who exhibit symptoms of distress may be at risk of poorer psychological and physical function at 12 months. Further research is required to understand the impact of psychological management early in the disease course.

Associations and gastrointestinal symptoms in women with endometriosis in comparison to women with irritable bowel syndrome: a study based on a population cohort

BACKGROUND

Endometriosis and irritable bowel syndrome (IBS) have similar symptoms, pathogenesis, and risk factors. These diagnoses often coexist and are frequently misdiagnosed leading to diagnostic delays. This study of a population-based cohort aimed to investigate associations relating to endometriosis and IBS and to compare gastrointestinal symptoms between endometriosis and IBS.

METHOD

The study cohort included women from the Malmö Offspring Study with information about endometriosis and IBS diagnoses from the National Board of Health and Welfare. The participants answered a questionnaire about lifestyle habits, medical and drug history, and self-reported IBS. The visual analog scale for IBS was used to estimate gastrointestinal symptoms the past 2 weeks. Endometriosis diagnosis and self-reported IBS were used as dependent variables to study associations with age, body mass index (BMI), education, occupation, marital status, smoking, alcohol habits, and physical activity using logistic regression. Mann-Whitney U Test or Kruskal-Wallis tests were used to calculate the differences in symptoms between groups.

RESULTS

Of the 2,200 women with information from medical records, 72 participants had endometriosis; 21 (29.2%) of these had self-reported IBS. Of the 1,915 participants who had answered the questionnaire, 436 (22.8%) had self-reported IBS. Endometriosis was associated with IBS (OR:1.86; 95%CI:1.06-3.26; p = 0.029), as well as with age 50-59 years (OR:6.92; 95%CI:1.97-24.32; p = 0.003), age ≥ 60 years (OR:6.27; 95%CI:1.56-25.17; p = 0.010), sick leave (OR:2.43; 95%CI:1.08-5.48; p = 0.033), and former smoking (OR:3.02; 95%CI:1.19-7.68; p = 0.020). There was an inverse association with BMI (OR:0.36; 95%CI:0.14-4.91; p = 0.031). IBS was associated with endometriosis (OR:1.77; 95%CI:1.02-3.07; p = 0.041) and sick leave (OR:1.77; 95%CI:1.14-2.73; p = 0.010), with a tendency to association with smoking (OR:1.30; 95%CI:0.98-1.72; p = 0.071). When excluding participants using drugs associated with IBS, the condition was associated with current smoking (OR:1.39; 95%CI:1.03-1.89; p = 0.033) and inversely with age 50-59 years (OR:0.58; 95%CI:0.38-0.90; p = 0.015). There were differences in the gastrointestinal symptoms between IBS and healthy participants, but not between endometriosis and IBS or healthy participants.

CONCLUSION

There were associations between endometriosis and IBS, without differences in gastrointestinal symptoms. Both IBS and endometriosis were associated with smoking and sick leave. Whether the associations reflect causality or depend on common risk factors and pathogenesis remains to be determined.

Epidemiologic and Genetic Associations of Endometriosis With Depression, Anxiety, and Eating Disorders

IMPORTANCE

Endometriosis is a common chronic gynecologic pathology with a large negative impact on women's health. Beyond severe physical symptoms, endometriosis is also associated with several psychiatric comorbidities, including depression and anxiety.

OBJECTIVE

To investigate whether pleiotropy contributes to the association of endometriosis with depression, anxiety, and eating disorders.

DESIGN, SETTING, AND PARTICIPANTS

This genetic association study was performed between September 13, 2021, and June 24, 2022, in 202 276 unrelated female participants. Genotypic and phenotypic information from the UK Biobank was combined with genome-wide association statistics available from the Psychiatric Genomics Consortium (11 countries), the Million Veteran Program (US), the FinnGen study (Finland), and the CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology) consortium (5 countries).

MAIN OUTCOMES AND MEASURES

The main outcomes were the phenotypic and genetic associations of endometriosis with anxiety, depression, and eating disorders.

RESULTS

A total of 8276 women with endometriosis (mean [SD] age, 53.1 [7.9] years) and 194 000 female controls (mean [SD] age, 56.7 [7.9] years) were included in the study. In a multivariate regression analysis accounting for age, body mass index, socioeconomic status, chronic pain-related phenotypes, irritable bowel syndrome, and psychiatric comorbidities, endometriosis was associated with increased odds of depression (odds ratio [OR], 3.61; 95% CI, 3.32-3.92), eating disorders (OR, 2.94; 95% CI, 1.96-4.41), and anxiety (OR, 2.61; 95% CI, 2.30-2.97). These associations were supported by consistent genetic correlations (rg) (depression rg, 0.36, P = 1.5 × 10-9; anxiety rg, 0.33, P = 1.17 × 10-5; and eating disorders rg, 0.61, P = .02). With the application of a 1-sample mendelian randomization, the genetic liabilities to depression and anxiety were associated with increased odds of endometriosis (depression: OR, 1.09; 95% CI, 1.08-1.11; anxiety: OR, 1.39; 95% CI, 1.13-1.65). A genome-wide analysis of pleiotropic associations shared between endometriosis and psychiatric disorders identified 1 locus, DGKB rs12666606, with evidence of pleiotropy between endometriosis and depression after multiple testing correction (z = -9.46 for endometriosis, z = 8.10 for depression, P = 5.56 × 10-8; false discovery rate q = 4.95 × 10-4).

CONCLUSIONS AND RELEVANCE

These findings highlight that endometriosis is associated with women's mental health through pleiotropic mechanisms. To our knowledge, this is the first large-scale study to provide genetic and phenotypic evidence of the processes underlying the psychiatric comorbidities of endometriosis.

Prevalence and Risk Factors of Central Sensitization in Women with Endometriosis

STUDY OBJECTIVE

To assess prevalence of central sensitization (CS) and its association with demographic and clinical factors in patients with endometriosis.

DESIGN

Single-center, observational, cross-sectional study.

SETTING

Tertiary center.

PATIENTS

Consecutive patients with endometriosis referred to the center from January 15, 2022, to April 30, 2022.

INTERVENTIONS

For each enrolled patient, demographic and clinical data were collected, and the presence of CS was measured using the CS Inventory questionnaire (score ≥40).

MEASUREMENTS AND MAIN RESULTS

Primary study outcome was CS prevalence, and secondary study outcomes were the associations between demographic and clinical factors and CS. The 95% confidence intervals for CS prevalence were obtained with Bayesian-derived Jeffreys method, and the associations between CS and demographic and clinical factors were evaluated with the chi-square test and Fisher's exact test, where appropriate. The variables significantly associated with CS were then included in a multivariable logistic regression model. The significance level was set at .05 for all analyses. During the study period, 285 eligible women were enrolled. CS prevalence was 41.4% (95% confidence interval, 35.8-47.2). At univariable analysis, infertility, moderate to severe pain symptoms (except for dyschezia), altered bowel movements, posterolateral parametrium involvement, hormonal therapy failure (HTF), and most of central sensitivity syndromes were significantly associated with CS occurrence. Multivariable analysis only confirmed the significant association of CS with moderate to severe chronic pelvic pain, posterolateral parametrium involvement, HTF, migraine or tension-type headache, irritable bowel syndrome, and anxiety or panic attacks.

CONCLUSION

CS has a high prevalence in patients with endometriosis, especially in those with moderate to severe chronic pelvic pain, posterolateral parametrium involvement, HTF, and 3 central sensitivity syndromes (i.e. migraine or tension-type headache, irritable bowel syndrome, anxiety or panic attacks). Given the association with HTF, identifying CS through CS Inventory might be useful to counsel the patient and to choose multimodal treatment.

Trends in hospitalizations due to endometriosis in Spain, 1999-2019

OBJECTIVE

Although there have been variations in the management of the patients with endometriosis, an important population of these women still require hospitalization . This study aimed to analyze the trends in hospital admissions associated with endometriosis from 1999 to 2019 in Spain.

METHODS

An observational study of temporal trends was performed including women aged 15 to 54 years who were admitted to hospital for endometriosis in Spain from 1999 to 2019. Data on hospitalizations were drawn from the minimum basic data set. The data source used for the population was the continuous civil registry. The study variables were: age, year of admission, type of admission (elective/emergency), if there was surgical intervention during admission and length of hospital stay. Direct age-standardized admission rates were calculated using the 2013 European Standard Population differentiating between hospital admissions for elective surgery and any emergency admissions. Joinpoint regression models were fitted to estimate the annual percent change (APC).

RESULTS

Admissions for elective surgery increased significantly, by 5.7% annually, until 2003, when they began to decrease slightly at different speeds until 2019. The mean APC for the entire study period was -0.88% (95%CI: -2.74; 1.02). There was a significant mean decrease of 4% in annual emergency admissions until 2012. Then, there was a significant average increase of 2% per year until 2019. Regarding the length of stay, there was a gradual decrease until 2012, after which slight, oscillating increases were apparent.

CONCLUSION

There was a reduction of hospital admissions for elective surgery to treat endometriosis from 2003 to 2019 in Spain but emergency hospitalizations due to endometriosis have been growing since 2012. The mean length of hospital decreased for the study period.

Association between Endometriosis, Irritable Bowel Syndrome and Eating Disorders: ENDONUT Pilot Study

Background and aim: Irritable bowel syndrome (IBS), eating disorders (ED) and endometriosis share common pathophysiological mechanisms, involving alterations of the gut−brain axis. The aim of the ENDONUT pilot study was to investigate an association between these three diseases by screening for IBS and ED in patients with endometriosis. Method: We included patients from the CIRENDO cohort (Inter-Regional North-West Cohort of women with ENDOmetriosis) with a recent documented diagnosis of endometriosis of less than 4 years, regardless of age, date of onset of symptoms, type of endometriosis (digestive or not), with or without endometriosis-related digestive surgery. Validated questionnaires were used to screen for IBS (Rome IV, Francis score), ED (SCOFF-F, EAT-26), and anxiety/depression (HAD). Anthropometric data and lifestyle habits were also collected. The primary composite endpoint was SCOFF-F and ROME-IV scores. Results: Among 100 patients meeting inclusion criteria, 54 patients completed all the questionnaires. Of these, 19 had a positive SCOFF-F score (35.2%), 26 had a positive ROME-IV score (48.1%), and 14 patients (25.9%) had both a positive SCOFF-F score and a positive ROME-IV score (p = 0.006). Patients with positive SCOFF-F and ROME-IV scores had significantly higher HAD-anxiety and depression scores (p < 0.05). Conclusion: These results suggest a significant association between IBS, ED and endometriosis. The prevalence of IBS and ED in our population is higher than in the general population. Larger studies are needed to confirm these results, to better understand this triad, and to improve the diagnostic and multidisciplinary therapeutic management of these patients.

Clinical use of artificial intelligence in endometriosis: a scoping review

Endometriosis is a chronic, debilitating, gynecologic condition with a non-specific clinical presentation. Globally, patients can experience diagnostic delays of ~6 to 12 years, which significantly hinders adequate management and places a significant financial burden on patients and the healthcare system. Through artificial intelligence (AI), it is possible to create models that can extract data patterns to act as inputs for developing interventions with predictive and diagnostic accuracies that are superior to conventional methods and current tools used in standards of care. This literature review explored the use of AI methods to address different clinical problems in endometriosis. Approximately 1309 unique records were found across four databases; among those, 36 studies met the inclusion criteria. Studies were eligible if they involved an AI approach or model to explore endometriosis pathology, diagnostics, prediction, or management and if they reported evaluation metrics (sensitivity and specificity) after validating their models. Only articles accessible in English were included in this review. Logistic regression was the most popular machine learning method, followed by decision tree algorithms, random forest, and support vector machines. Approximately 44.4% (n = 16) of the studies analyzed the predictive capabilities of AI approaches in patients with endometriosis, while 47.2% (n = 17) explored diagnostic capabilities, and 8.33% (n = 3) used AI to improve disease understanding. Models were built using different data types, including biomarkers, clinical variables, metabolite spectra, genetic variables, imaging data, mixed methods, and lesion characteristics. Regardless of the AI-based endometriosis application (either diagnostic or predictive), pooled sensitivities ranged from 81.7 to 96.7%, and pooled specificities ranged between 70.7 and 91.6%. Overall, AI models displayed good diagnostic and predictive capacity in detecting endometriosis using simple classification scenarios (i.e., differentiating between cases and controls), showing promising directions for AI in assessing endometriosis in the near future. This timely review highlighted an emerging area of interest in endometriosis and AI. It also provided recommendations for future research in this field to improve the reproducibility of results and comparability between models, and further test the capacity of these models to enhance diagnosis, prediction, and management in endometriosis patients.

Endometriosis and irritable bowel syndrome: A systematic review and meta-analyses

Objective

To estimate the pooled odds ratio of endometriosis and irritable bowel syndrome, and to estimate the pooled prevalence of irritable bowel syndrome in patients with endometriosis.

Data sources

Using Cochrane Library, MEDLINE, Science Direct, ClinicalTrials.gov, Web of Science, and CINAHL, we conducted a systematic literature search through October 2021, using the key terms “endometriosis” and “irritable bowel syndrome.” Articles had to be published in English or Spanish. No restriction on geographical location was applied.

Methods of study selection

The following eligibility criteria were applied: full-text original articles; human studies; studies that investigated the association between endometriosis and irritable bowel syndrome. Two investigators screened and reviewed the studies. A total of 1,776 studies were identified in 6 separate databases. After screening and applying the eligibility criteria, a total of 17 studies were included for analyses. The meta-analysis of association between endometriosis and irritable bowel syndrome included 11 studies, and the meta-analysis on the prevalence of irritable bowel syndrome in endometriosis included 6 studies.

Tabulation, integration, and results

Overall 96,119 subjects were included in the main meta-analysis (11 studies) for endometriosis and irritable bowel syndrome, with 18,887 endometriosis patients and 77,171 controls. The odds of irritable bowel syndrome were approximately 3 times higher among patients with endometriosis compared with healthy controls (odds ratio 2.97; 95% confidence interval, 2.17 – 4.06). Similar results were obtained after subgroup analyses by endometriosis diagnosis, irritable bowel syndrome diagnostic criteria, and Newcastle-Ottawa Scale scores. Six studies reported prevalence rates of irritable bowel syndrome in women with endometriosis, ranging from 10.6 to 52%. The pooled prevalence of irritable bowel syndrome in women with endometriosis was 23.4% (95% confidence interval, 9.7 – 37.2).

Conclusion

Patients with endometriosis have an approximately threefold increased risk of developing irritable bowel syndrome. Development and recent update of Rome criteria has evolved the diagnosis of IBS, potential bias should still be considered as there are no specific tests available for diagnosis.

Systematic Review Registration

[https://www.crd.york.ac.uk/prospero/displa y_record.php?ID=CRD42018080611], identifier [CRD42018080611].

Revisiting the Risk Factors for Endometriosis: A Machine Learning Approach

Endometriosis is a condition characterized by implants of endometrial tissues into extrauterine sites, mostly within the pelvic peritoneum. The prevalence of endometriosis is under-diagnosed and is estimated to account for 5-10% of all women of reproductive age. The goal of this study was to develop a model for endometriosis based on the UK-biobank (UKB) and re-assess the contribution of known risk factors to endometriosis. We partitioned the data into those diagnosed with endometriosis (5924; ICD-10: N80) and a control group (142,723). We included over 1000 variables from the UKB covering personal information about female health, lifestyle, self-reported data, genetic variants, and medical history prior to endometriosis diagnosis. We applied machine learning algorithms to train an endometriosis prediction model. The optimal prediction was achieved with the gradient boosting algorithms of CatBoost for the data-combined model with an area under the ROC curve (ROC-AUC) of 0.81. The same results were obtained for women from a mixed ethnicity population of the UKB (7112; ICD-10: N80). We discovered that, prior to being diagnosed with endometriosis, affected women had significantly more ICD-10 diagnoses than the average unaffected woman. We used SHAP, an explainable AI tool, to estimate the marginal impact of a feature, given all other features. The informative features ranked by SHAP values included irritable bowel syndrome (IBS) and the length of the menstrual cycle. We conclude that the rich population-based retrospective data from the UKB are valuable for developing unified machine learning endometriosis models despite the limitations of missing data, noisy medical input, and participant age. The informative features of the model may improve clinical utility for endometriosis diagnosis.

Endometriosis and irritable bowel syndrome: similarities and differences in the spectrum of comorbidities

STUDY QUESTION

Do the spectrum and prevalence of comorbidities of endometriosis and irritable bowel syndrome (IBS) overlap?

SUMMARY ANSWER

Despite several overlapping symptoms, the most significantly associated comorbidities of endometriosis and IBS are different and are rather related to the organ systems primarily involved in the index diagnosis.

WHAT IS KNOWN ALREADY

Endometriosis and IBS both have several similar unspecific symptoms, such as recurrent abdominal pain, cramping and anxiety, and both diseases affect young women and are associated with a number of comorbidities causing a poor quality of life. However, a detailed study, revealing the full spectrum of endometriosis and IBS comorbidities in the same study population, is lacking.

STUDY DESIGN, SIZE, DURATION

This article presents a retrospective in silico analysis of the data from a large nationwide biobank-based cohort consisting of 121 773 women. After excluding all first- and second-degree relatives, the data of up to 65 421 women were analyzed.

PARTICIPANTS/MATERIALS, SETTING, METHODS

International Classification of Disease-10 diagnosis main codes associated with endometriosis (N80) and IBS (K58) diagnoses were identified from the Estonian Biobank dataset by linking with the Estonian Health Insurance Fund and other relevant registries. The associations between N80 and K58 and other diagnosis codes were tested using logistic regression, adjusting for age at recruitment and 10 genetic principal components to account for potential population stratification. Bonferroni correction was applied to account for multiple testing.

MAIN RESULTS AND THE ROLE OF CHANCE

Both women with endometriosis and IBS suffered from more conditions compared to the control group, with 226 and 428 diagnosis codes statistically significantly more frequent in women with respective diagnosis compared to controls. Women suffering from both conditions had 275 significantly associated comorbidities. A remarkable proportion of women with IBS or endometriosis suffered also from endometriosis (9.0%) or IBS (13.6%), respectively. In endometriosis, the most prevalent diagnoses were related to diseases of the genitourinary system (33 N-category codes) and in women with IBS, the most associated diagnoses were related to digestive disorders and gastrointestinal tract (52 codes from K-category). Among the most significant diagnoses in endometriosis were uterine leiomyomas (D25), menstrual disorders (N92) and infertility (N97) (P < 1 × 10-315 for all), and in IBS, lactose intolerance (E73), gastritis and duodenitis (K29) and functional dyspepsia (K30) were in the top list of most significant comorbidities (P < 1 × 10-315 for all).

LIMITATIONS, REASONS FOR CAUTION

The information about the severity stages of endometriosis and subtypes of IBS was not available for analysis. The findings may not be fully extrapolated to all female populations, because all participants were from one geographic area and had good access to health services.

WIDER IMPLICATIONS OF THE FINDINGS

These findings support previous studies that have found a high prevalence of pre-selected comorbidities in women with endometriosis and IBS. However, taking into account the differences in the full spectrum of comorbidities of endometriosis and IBS may aid in diagnosing these disorders. Women and healthcare providers need to be aware that women with endometriosis are at high risks of complications during pregnancy and should be carefully monitored.

STUDY FUNDING/COMPETING INTEREST(S)

This research was funded by the Estonian Research Council (grant PRG1076), Horizon 2020 innovation grant (ERIN, grant no. EU952516), Enterprise Estonia (grant no. EU48695), MSCA-RISE-2020 project TRENDO (grant no. 101008193) and by the European Union through the European Regional Development Fund (Projects no. 2014-2020.4.01.15-0012 and no. 2014-2020.4.01.16-0125). The authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Endometriosis Is Undervalued: A Call to Action

Endometriosis is an inflammatory chronic pain condition caused by uterine tissue growing outside of the uterus that afflicts at least 11% of women (and people assigned female at birth) worldwide. This condition results in a substantial burden to these women, and society at large. Although endometriosis was first identified over 160 years ago, substantial knowledge gaps remain, including confirmation of the disease's etiology. Research funding for endometriosis is limited, with funding from bodies like the National Institutes of Health (NIH) constituting only 0.038% of the 2022 health budget—for a condition that affects 6.5 million women in the US alone and over 190 million worldwide. A major issue is that diagnosis of endometriosis is frequently delayed because surgery is required to histologically confirm the diagnosis. This delay increases symptom intensity, the risk of central and peripheral sensitization and the costs of the disease for the patient and their nation. Current conservative treatments of presumed endometriosis are pain management and birth control. Both of these methods are flawed and can be entirely ineffective for the reduction of patient suffering or improving ability to work, and neither addresses the severe infertility issues or higher risk of certain cancers. Endometriosis research deserves the funding and attention that befits a disease with its substantial prevalence, effects, and economic costs. This funding could improve patient outcomes by introducing less invasive and more timely methods for diagnosis and treatment, including options such as novel biomarkers, nanomedicine, and microbiome alterations.

A 10-Year Journey to Diagnosis With Endometriosis: An Autobiographical Case Report

Endometriosis is a multifocal, chronic disease defined by extrauterine endometrial glands and stroma. This case report describes the author’s experience of living with stage IV endometriosis, including a 10-year diagnostic delay, the impact on daily life, management, and treatment. The diagnostic delay for endometriosis averages between seven to nine years globally, which imparts significant physical, psychological, and financial effects on the lives of patients.

Review article: Physical and psychological comorbidities associated with irritable bowel syndrome

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal disorders encountered by physicians in primary and secondary care. Patients with IBS commonly present with various extraintestinal complaints, which account for a substantial clinical and economic burden. The common extraintestinal comorbidities associated with IBS include anxiety, depression, somatisation, fibromyalgia, chronic fatigue syndrome, chronic pelvic pain, interstitial cystitis, sexual dysfunction and sleep disturbance. The presence of comorbidity in IBS poses a diagnostic and therapeutic challenge with patients frequently undergoing unnecessary investigations and interventions, including surgery. This review discusses the different physical and psychological comorbidities associated with IBS, the shared pathophysiological mechanisms and potential management strategies.

Lifestyle and Chronic Pain in the Pelvis: State of the Art and Future Directions

During their lifespan, many women are exposed to pain in the pelvis in relation to menstruation and pregnancy. Such pelvic pain is often considered normal and inherently linked to being a woman, which in turn leads to insufficiently offered treatment for treatable aspects related to their pain experience. Nonetheless, severe dysmenorrhea (pain during menstruation) as seen in endometriosis and pregnancy-related pelvic girdle pain, have a high impact on daily activities, school attendance and work ability. In the context of any type of chronic pain, accumulating evidence shows that an unhealthy lifestyle is associated with pain development and pain severity. Furthermore, unhealthy lifestyle habits are a suggested perpetuating factor of chronic pain. This is of specific relevance during lifespan, since a low physical activity level, poor sleep, or periods of (di)stress are all common in challenging periods of women’s lives (e.g., during menstruation, during pregnancy, in the postpartum period). This state-of-the-art paper aims to review the role of lifestyle factors on pain in the pelvis, and the added value of a lifestyle intervention on pain in women with pelvic pain. Based on the current evidence, the benefits of physical activity and exercise for women with pain in the pelvis are supported to some extent. The available evidence on lifestyle factors such as sleep, (di)stress, diet, and tobacco/alcohol use is, however, inconclusive. Very few studies are available, and the studies which are available are of general low quality. Since the role of lifestyle on the development and maintenance of pain in the pelvis, and the value of lifestyle interventions for women with pain in the pelvis are currently poorly studied, a research agenda is presented. There are a number of rationales to study the effect of promoting a healthy lifestyle (early) in a woman’s life with regard to the prevention and management of pain in the pelvis. Indeed, lifestyle interventions might have, amongst others, anti-inflammatory, stress-reducing and/or sleep-improving effects, which might positively affect the experience of pain. Research to disentangle the relationship between lifestyle factors, such as physical activity level, sleep, diet, smoking, and psychological distress, and the experience of pain in the pelvis is, therefore, needed. Studies which address the development of management strategies for adapting lifestyles that are specifically tailored to women with pain in the pelvis, and as such take hormonal status, life events and context, into account, are required. Towards clinicians, we suggest making use of the window of opportunity to prevent a potential transition from localized or periodic pain in the pelvis (e.g., dysmenorrhea or pain during pregnancy and after delivery) towards persistent chronic pain, by promoting a healthy lifestyle and applying appropriate pain management.

Irritable bowel syndrome in midlife women: a narrative review

Midlife women between the ages of 40 and 65 years have reported multiple challenges due to menopausal, developmental, and situational transitions from younger to older adulthood. During the midlife period, many women seek health care for gastrointestinal symptoms and irritable bowel syndrome (IBS). Multiple factors including stress, poor sleep, diet, and physical inactivity may contribute to IBS or gastrointestinal symptoms in midlife women. As such, a comprehensive assessment and treatment approach is needed for midlife women suffering gastrointestinal symptoms. This article reviews the main aspects of the menopausal transition, sex hormonal changes, abdominal and pelvic surgery, psychosocial distress, behavioral factors, and gut microbiome, as well as their relevance on IBS and gastrointestinal symptoms in midlife women. Also, management strategies for IBS in midlife women are discussed. To date, gastrointestinal symptoms during midlife years remain a critical area of women’s health. Additional research is needed to better understand the contributors to gastrointestinal symptoms in this group. Such efforts may provide a new window to refine or develop treatments of gastrointestinal symptoms for midlife women.