Familial risk for endometriosis and its interaction with smoking, age at menarche and body mass index: a population-based cohort study among siblings

The mitochondrial DNA copy number and ovary-related reproductive disorders: A bidirectional two-sample Mendelian randomization study

OBJECTIVE

In the present study, a bidirectional two-sample Mendelian randomization approach was utilized to explore potential causal relationships between mitochondrial DNA copy number (mtDNA-CN) and ovary-related reproductive disorders (ORRDs), including ovarian dysfunction, ovarian cyst, polycystic ovary syndrome (PCOS), premature ovarian failure (POF) and ovarian endometriosis.

METHODS

Genetic associations with mtDNA-CN were obtained from three genome-wide association study (GWAS) summary statistics from the UK Biobank, and ORRD data were investigated using summary statistics from the FinnGen cohort. Single nucleotide polymorphisms (SNPs) correlated with mtDNA-CN were selected as genetic instrumental variables (IVs) to estimate the causal effect of mtDNA-CN on ORRDs using the inverse-variance weighted (IVW) method with heterogeneity and pleiotropy analysis, and we repeated this in the opposite direction using instruments for ORRDs.

RESULTS

We found that the genetically predicted mtDNA was indicative of increased levels of PCOS (OR = 1.16; P < 0.001) and ovarian endometriosis (OR = 1.25; P = 0.007) in the IVW analysis and was not associated with the risk of other ORRDs. In the reverse direction, genetically predicted ORRDs were not associated with mtDNA-CN levels in the IVW analysis. Sensitivity and replication analyses showed the results to be stable.

CONCLUSION

We found that mtDNA-CN may increase the risk of PCOS and ovarian endometriosis. This may have implications for mtDNA-CN as a biomarker for these conditions in clinical practice.

Concurrent detection of the mitochondrial DNA copy number and the +35G/C polymorphism in the mitochondrial transcription factor A gene in endometriosis

BACKGROUND AND AIM

Endometriosis is a chronic gynecological inflammatory disease. The mitochondrial DNA copy number (mtDNA CN) and mitochondrial transcription factor A (TFAM) are known to contribute to human pathologies and cancer. Therefore, this study aims to reveal the association of mtDNA CN and TFAM+35G/C (rs1937) polymorphism with the risk of endometriosis in Egyptian females.

MATERIALS AND METHODS

This case-control study involved 160 Egyptian females divided into two groups: 80 endometriosis cases and 80 controls. The mtDNA CN was quantified using a real-time quantitative PCR (qPCR), and the TFAM +35G/C SNP (rs1937) was genotyped using the TaqMan allelic discrimination assay technique.

RESULTS

The mtDNA CN was markedly decreased in endometriosis cases compared to controls (P < 0. 001). TFAM rs1937 genotypes and allele distributions were all in Hardy-Weinberg equilibrium. The GC genotype and the 'C' allele frequency (P = 0.015 and P = 0.017, respectively) were substantially greater in endometriosis cases.

CONCLUSION

Decreased mtDNA CN and the GC genotype of TFAM +35G/C polymorphism were significantly associated with the risk of endometriosis in Egyptian females.

Causal effects of endometriosis stages and locations on menstruation, ovulation, reproductive function, and delivery modes: a two-sample Mendelian randomization study

Background

Endometriosis is a chronic inflammatory disease of women during their reproductive years. The relationship between the severity and location of endometriosis and menstruation, ovulation, reproductive function, and mode of delivery remains unclear.

Methods

We explored the association between the various phenotypes of endometriosis and menstruation, ovulation, reproductive function, and mode of delivery, using two-sample Mendelian randomization (MR) and summary data on endometriosis stages and locations from the FinnGen consortium and women's menstruation, ovulation, reproductive function, and mode of delivery from OpenGWAS and ReproGen. Inverse-variance weighting was used for the primary MR analysis. In addition, a series of sensitivity analyses, confounding analyses, co-localization analyses, and multivariate MR analyses were performed.

Results

MR analysis showed a negative effect of moderate to severe endometriosis on age at last live birth (OR = 0.973, 95% CI: 0.960-0.986) and normal delivery (OR = 0.999, 95% CI: 0.998-1.000; values for endpoint were excluded), ovarian endometriosis on age at last live birth (OR = 0.976, 95% CI: 0.965-0.988) and normal delivery (OR = 0.999, 95% CI: 0.998-1.000; values for endpoint were excluded), and fallopian tubal endometriosis on excessive irregular menstruation (OR = 0.966, 95% CI: 0.942-0.990). Bidirectional MR analysis showed that age at menarche had a negative causal effect on intestinal endometriosis (OR = 0.417, 95% CI: 0.216-0.804). All MR analyses were confirmed by sensitivity analyses, and only the genetic effects of moderate to severe endometriosis on normal delivery and age at last live birth were supported by co-localization evidence.

Conclusion

Our findings deepen the understanding of the relationship between various types of endometriosis and menstruation, ovulation, reproductive function, and mode of delivery and clarify the important role of moderate to severe endometriosis.

Association Between the Oxidative Balance Score and Endometriosis: A Population-Based Study

Purpose

To investigate the association between the oxidative balance score (OBS) and endometriosis.

Methods

This cross-sectional study used four cycles of the National Health and Nutrition Examination Survey (NHANES) (1999-2000, 2001-2002, 2003-2004, and 2005-2006). OBS involved 16 dietary nutrients and 4 lifestyle factors, including 5 pro-oxidants and 15 anti-oxidants. According to weighted quartiles, the OBS was divided into four categories: < 12.54, 12.54-18.70, 18.71-24.68, and > 24.68. Endometriosis was diagnosed based on a question from the reproductive health questionnaire. Weighted multivariate logistic analysis was used to investigate the association between OBS and endometriosis. Subgroup analysis was performed based on menstrual regularity and female hormone use.

Results

A total of 5095 women were included, with 1140 (22.37%), 1232 (24.18%), 1224 (24.02%), and 1499 (29.42%) women in the OBS < 12.54, of 12.54-18.70, of 18.71-24.68, and > 24.68 categories, respectively. After adjusting age, race, family poverty-to-income ratio (PIR), education level, uterine fibroids, menstrual regularity, oophorectomy, female hormone use, hypertension, dyslipidemia, and steroid drug, a high OBS (> 24.68) was found to be associated with lower odds of endometriosis [odds ratio (OR) = 0.70, 95% confidence interval (CI): 0.50-0.97, P = 0.033] compared to a low OBS (< 12.54). The similar result was also found in women with irregular menstruation (OR = 0.58, 95% CI: 0.37-0.91, P = 0.020) and with female hormone use (OR = 0.71, 95% CI: 0.52-0.98, P = 0.037).

Conclusion

A high OBS was associated with lower odds of endometriosis, especially in women with irregular menstruation and female hormone use.

Gene associations of lipid traits, lipid-lowering drug-target genes and endometriosis

RESEARCH QUESTION

Does the observed correlation between dyslipidaemia and endometriosis indicate a bidirectional causal association?

DESIGN

Bidirectional Mendelian randomization was used to investigate the causal association between lipid traits and endometriosis. Drug-target Mendelian randomization was used to explore potential drug-target genes for managing endometriosis. In cases where lipid-mediated effects via specific drug targets were significant, aggregate analyses, such as summary-data-based Mendelian randomization and colocalization methods, were introduced to validate the outcomes. Mediation analyses supplemented these evaluations.

RESULTS

The bidirectional Mendelian randomization results suggested that genetically predicted triglyceride (OR 1.15, 95% CI 1.08-1.23), high-density lipoprotein cholesterol (OR 0.87, 95% CI 0.81-0.94), low-density lipoprotein cholesterol (OR 1.20, 95% CI 1.06-1.34) and apolipoprotein A (OR 0.90, 95% CI 0.83-0.96) concentrations were causally associated with endometriosis. Reverse Mendelian randomization results revealed that genetically proxied endometriosis was causally associated with triglyceride concentration (OR 1.02, 95% CI 1.01-1.02). In drug-target Mendelian randomization, genetic mimicry in proprotein convertase subtilisin/kexin type 9 (PCSK9) (OR 1.40, 95% CI 1.13-1.72), apolipoprotein B (APOB) (OR 1.49, 95% CI 1.21-1.86) and angiopoietin-related protein 3 (ANGPTL3) (OR 1.57, 95% CI 1.14-2.16) was significantly associated with the risk of endometriosis stages 1-2.

CONCLUSION

There is a potential bidirectional causal association between endometriosis and dyslipidaemia. Genetic mimicry of PCSK9, APOB and ANGPTL3 is associated with the risk of early-stage endometriosis. The development of lipid-lowering drugs to treat endometriosis is of potential clinical interest.

Transgenic mice applications in the study of endometriosis pathogenesis

Endometriosis (EM), characterized by ectopic growth of endometrial tissues and recurrent pelvic pain, is a common disease with severe negative impacts on the life quality of patients. Conventional uterine tissue transplantation-based models have been broadly used to investigate the pathogenic mechanism(s) of EM. Transgenic mice with whole body or uterine/pelvic tissue-specific labelling by the expression of GFP, β-gal or other light-emitting or chromogenic markers enable investigators to analyze the contribution to endometriotic lesions by the donor or recipient side after uterine tissue transplantation. Moreover, when coupled to uterine tissue transplantation, transgenic mice with a specific EM-related gene knocked out or overexpressed make it possible to determine the gene's in vivo role(s) for EM pathogenesis. Furthermore, observations on the rise of de novo endometriotic lesions as well as structural/functional changes in the eutopic endometrium or pelvic tissues after gene manipulation will directly relate the cognate gene to the onset of EM. A major advantage of transgenic EM models is their efficiency for analyzing gene interactions with hormonal, dietetic and/or environmental factors. This review summarizes the features/sources/backgrounds of transgenic mice and their applications to EM studies concerning hormonal regulation, angiogenesis and inflammation. Findings from these studies, the advantages/disadvantages of transgenic EM models, and future expectations are also discussed.

Factors influencing health-related quality of life in women with endometriosis: A cross-sectional study

This study aimed to assess the health-related quality of life and identify its associated factors in women with endometriosis. A cross-sectional correlation study design and convenience sampling were conducted in the gynecological outpatient clinic of a teaching hospital in northern Taiwan. A total of 216 women with endometriosis were recruited. The data were collected using structured questionnaires and analyzed using descriptive and inferential statistics. Participants reported a moderate level of health-related quality of life. The most significant impact of endometriosis on health-related quality of life was emotional well-being, followed by feeling of control or powerless, pain, social support, and self-image. Educational attainment, menstrual cycle, period length, perceived menstrual flow, symptom distress, and self-management strategies explained 66% of the variance in health-related quality of life. Factors influencing health-related quality of life in women with endometriosis play a key role in promoting women's well-being. Interventions based on these related factors should be developed and taken into practice to effectively manage the disease-related symptoms for women with endometriosis and thereby improve their overall health-related quality of life.

Impact of family history for endometriosis, migraine, depression and early menopause on endometriosis symptoms, localization and stage: A case control study

INTRODUCTION

Endometriosis is a common disabling pain condition in women of childbearing age, frequently showing familial clustering. Nevertheless, little is known about whether familial predispositions influence its severity or presentation. In this study, we investigate disease characteristics in endometriosis patients with a family history (FH) for endometriosis or the comorbidities migraine, depression and early menopause (EMP).

MATERIALS AND METHODS

We performed an observational case-control study enrolling women with histologically confirmed endometriosis in a tertiary center. Based on surgical findings, patient records and phone interviews, we examined the relations between a FH for endometriosis, migraine, depression or EMP and endometriotic signs and symptoms, such as response to combined hormonal contraceptives (CHC) and analgesics, disease localization, infiltration depth, Enzian- and rASRM-scores.

RESULTS

A positive FH for endometriosis, migraine, depression or EMP was reported by 10.2 %, 33.4 %, 32.6 % and 9.9 % of the 344 patients. A positive FH of endometriosis was associated with an increased risk for high rASRM-scores (rASRM 3 + 4: OR 2.74 (95 % CI 1.16-6.49), p = 0.017) and the presence of endometriomas (OR 2.70 (1.22-5.95), p = 0.011). A positive FH for migraine was associated with less response of endometriosis symptoms to CHC (OR 0.469 (0.27-0.82) p = 0.025). Depression in the family was linked to less severe rASRM-scores (rASRM 3 + 4: OR 0.63 (0.39-0.99), p = 0.046) and less endometriomas (OR 0.58 (0.67-0.92), p = 0.02), but increased the risk of both migraine (OR 1.66 (1.01-2.73), p = 0.043) and depression (OR 3.04 (1.89-4.89), p < 0.001) while showing a better response to CHC (OR 2.0 (1.15-3.48, p < 0.001). Patients with EMP in their family reported more current endometriosis symptoms at present (OR 3.72 (1.67-8.30), p = 0.001), more dysmenorrhea (OR 2.13 (1.04-4.35), p = 0.037), more frequent severe dysmenorrhea (OR 2.32 (1.14-4.74), p = 0.019) and suffered significantly more often > 5 days of non-cyclic pain (OR 3.58 (1.72-7.44), p < 0.001).

CONCLUSIONS

Around 30% reported a positive FH for migraine or depression. Patients with a positive FH for endometriosis, migraine, depression or EMP differ in symptoms and surgical findings when compared to controls. While a FH for endometriosis is associated with higher rASRM scores and more endometriomas, women with a FH for depression had lower rASRM scores and less endometriomas while responding better to CHC. In contrast, women with a FH for migraine showed less response to CHC.

The Clinical Picture and Fecundity of Primary and Recurrent Ovarian Endometriosis with Family History: A Retrospective Analysis

This study aims to evaluate the role of endometriosis family history on the clinical manifestation and fertility performance of primary and recurrent endometriosis. In total, 312 primary and 323 recurrent endometrioma patients with a histological diagnosis were included in this study. Family history was significantly correlated with recurrent endometriosis (adjusted OR: 3.52, 95% CI: 1.09-9.46, p = 0.008). Patients with a family history showed a significantly higher proportion of recurrent endometriosis (75.76% vs. 49.50%), higher rASRM scores, higher incidence of severe dysmenorrhea, and severe pelvic pain than the sporadic cases. Recurrent endometrioma showed statistical increase in rASRM scores, percentage of rASRM Stage IV, dysmenorrhea, dyschezia, those undergoing semi-radical surgery or unilateral oophorosalpingectomy, postoperative medical treatment, e with a positive family history, while a decrease in the incidence of asymptomatic phenomena and those undergoing ovarian cystectomy compared to those with primary endometriosis. The naturally conceived pregnancy rate was higher in primary endometriosis compared to recurrent endometriosis. Compared to recurrent endometriosis with a negative family history, recurrent endometriosis with a positive family history had a higher incidence of severe dysmenorrhea, chronic pelvic pain, a higher spontaneous abortion rate, and a lower natural pregnancy rate. Primary endometriosis with a family history presented a higher incidence of severe dysmenorrhea than those without a family history. In conclusion, endometriosis patients with a positive family history presented a higher pain severity and lower conception probability compared to the sporadic cases. Recurrent endometriosis showed further-exacerbated clinical manifestations, more pronounced familial tendency, and lower pregnancy rates than primary endometriosis.

Status and related factors of postoperative recurrence of ovarian endometriosis: a cross-sectional study of 874 cases

PURPOSE

Exploring the status and related factors of postoperative recurrence of ovarian endometriosis.

METHODS

This study analyzed the results of questionnaires conducted in 27 hospitals across the country from January 2019 to November 2021. All women were divided into recurrence group and non-recurrence group to analyze the recurrence rate and related factors after ovarian endometriosis surgery.

RESULTS

The recurrence rates of ovarian endometriosis within 1 year, 1-2 years, 2-3 years, 3-4 years, 4-5 years and more than 5 years were 6.27%, 35.85%, 55.38%, 65.00% and 56.82%, respectively. Significant differences were found between two groups in terms of age at surgery (OR: 0.342, 95%CI: 0.244-0.481, P < 0.001), presence of dysmenorrhea (OR: 1.758, 95%CI: 1.337-2.312, P < 0.001), presence of adenomyosis (OR: 1.948, 95%CI: 1.417-2.678, P < 0.001) and family history of endometriosis or adenomyosis (OR: 1.678, 95%CI: 1.035-2.721, P = 0.021). The age at surgery (OR: 0.358, 95%CI: 0.253-0.506, P < 0.001), presence of dysmenorrhea (OR: 1.379, 95%CI: 1.026-1.853, P = 0.033) and presence of adenomyosis (OR: 1.799, 95%CI: 1.275-2.537, P = 0.001) were significantly associated with endometrioma recurrence in multivariate analysis. No significant associations were found between the recurrence rate and body mass index (BMI), educational background, age of menarche, gravida, parity, uterine leiomyoma, endometrial polyps or postoperative use of gonadotropin-releasing hormone agonist (GnRH-a).

CONCLUSIONS

Dysmenorrhea and presence of adenomyosis are independent risk factors for postoperative recurrence of ovarian endometriosis, and older age is an independent protective factor for postoperative recurrence.

Height and pelvic lesion number: Do they have a positive relationship with postoperative recurrence in adolescent endometriosis?-A retrospective clinical analysis of 89 adolescent endometriosis in China

BACKGROUND

Adolescent endometriosis is a special type of endometriosis. Its diagnosis is often delayed. This study aimed to share the treatment experience of adolescent endometriosis and analyze the clinical manifestation, clinical stage, and risk factors of postoperative recurrence in China.

METHODS

Eighty-nine cases of adolescent endometriosis over 7 years in a single institution were reviewed. Demographic, clinical outcome measures were collected.

RESULT

The cumulative incidence rates of postoperative recurrence at years 1, 2, 3, 4, and 5 were 13.2%, 15.09%, 16.98%, 20.75%, and 20.75%, respectively. The risk factors associated with postoperative recurrence were disease stage, number of lesions, and height. In multivariate analysis, the independent risk factors of postoperative recurrence were height (RR: 1.132, 95% CI: 1.018-1.260) and the number of pelvic lesions (three or more, RR: 4.202, 95% CI: 1.013-17.433).

CONCLUSION

Taller patients and those who had multiple lesion sites (≥3) should receive more attention, because they have a higher possibility of relapse after surgery than their counterparts. This finding can guide the postoperative treatment of adolescent patients with endometrioma.

Body mass index and endometriosis: Is there a relationship?

Objective:

Previous studies on the relationship between the presence of endometriosis (EM) and body mass index (BMI) have shown inconsistent results. This study aimed to compare the BMI between women with EM and non-endometriotic controls.

Methods:

In the present cross-sectional study, BMI of 65 endometriotic women with 43 non-endometriotic controls undergoing laparoscopy were compared. The comparison of BMI between the two groups and in disease stages was analyzed using t-test.

Results:

BMI was significantly lower in women with EM compared to control women ( p = 0.01). There were no statistically significant differences in BMI between disease stages.

Conclusion:

The present study results showed that women with EM have lower BMI compared to non-endometriotic controls. More studies are suggested to clarify the mechanisms of this association.

Uncovering Evidence: Associations between Environmental Contaminants and Disparities in Women's Health

Over the years, industrial accidents and military actions have led to unintentional, large-scale, high-dose human exposure to environmental contaminants with endocrine-disrupting action. These historical events, in addition to laboratory studies, suggest that exposure to toxicants such as dioxins and polychlorinated biphenyls negatively impact the reproductive system and likely influence the development of gynecologic diseases. Although high-level exposure to a single toxicant is rare, humans living in industrialized countries are continuously exposed to a complex mixture of manmade and naturally produced endocrine disruptors, including persistent organic pollutants and heavy metals. Since minorities are more likely to live in areas with known environmental contamination; herein, we conducted a literature review to identify potential associations between toxicant exposure and racial disparities in women's health. Evidence within the literature suggests that the body burden of environmental contaminants, especially in combination with inherent genetic variations, likely contributes to previously observed racial disparities in women's health conditions such as breast cancer, endometriosis, polycystic ovarian syndrome, uterine fibroids, and premature birth.