Risk of Rheumatoid Arthritis in Patients with Endometriosis: A Nationwide Population-Based Cohort Study

Association Between Composite Dietary Antioxidant Index and the Risk of Endometriosis-Related Rheumatoid Arthritis in Women of Childbearing Age: A Cross-Sectional Study Based on the National Health and Nutrition Examination Survey Database

Purpose

To evaluate the association between Composite Dietary Antioxidant Index (CDAI) and the risk of endometriosis (EM)-related rheumatoid arthritis (RA) in women of childbearing age.

Methods

Using the data from the National Health and Nutrition Examination Survey database, this cross-sectional study included women of childbearing age. The CDAI was obtained by summing the standardized Z-values of the dietary intakes. EM was diagnosed based on a questionnaire-based survey. The outcome of this study was the presence of RA, which was defined by a questionnaire. The associations of CDAI and EM with the risk of RA were determined using weighted logistic analysis. Additive interaction was evaluated using the relative excess risk due to interaction (RERI), the attributable proportion due to interaction (AP), and the synergy index (S).

Results

In total, 3803 patients were included, of which 74 patients (1.99%) were with RA. A lower CDAI [odds ratio (OR): 1.85, 95% confidence interval (CI): 1.12 to 3.04, P= 0.015] and the presence of EM (OR: 3.05, 95% CI: 1.19 to 7.81, P= 0.023) was associated with the risk of RA. The result demonstrated an additive interaction of a lower CDAI and the presence of EM on the risk of RA (OR: 6.19, 95% CI: 2.33 to 16.43, P <0.001, P of trend =0.007). Nevertheless, there was no significant additive interaction after being assessed by the RERI, AP, and S. However, a joint effect of a lower CDAI and EM on the risk of RA (OR: 3.94, 95% CI: 1.35 to 11.51, P= 0.013) was observed.

Conclusion

Our study identified EM, and lower CDAI, was related to the risk of RA. Lower CDAI score was also associated with the risk of EM-related RA. This study indicates the importance of antioxidant intake in daily diet for the management of EM-related RA.

Reproductive Effect by Rheumatoid Arthritis and Related Autoantibodies

Rheumatoid arthritis (RA) is a common inflammatory arthritis in women. The effects of RA on the reproductive system are usually overlooked, as RA is not diagnosed until later in reproductive age. Whether RA itself or its related rheumatoid antibodies have an impact on female reproductive function has long been a thought-provoking issue. In brief, relevant epidemiological evidence has shown that women affected by RA are more likely to have coexisting reproductive disorders, including infertility, endometriosis, and premature ovarian insufficiency (POI), or to subsequently develop them. Furthermore, linkage between RA and pregnancy loss (PL) as well as polycystic ovary syndrome (PCOS) is also well known, albeit controversial in available evidence. RA and reproductive disorders appear to share a similar inflammatory immune response and genetic background. The stress experienced by patients with RA may affect their reproductive choices to some extent. Notably, few studies have explored the impact of rheumatoid antibodies such as rheumatoid factors (RFs) and anti-citrullinated protein antibodies (ACPAs) on reproductive disorders. Although it has been mentioned that the rate of RF and/or ACPA positivity is higher in women with a history of PL and POI, the clinical relevance of this relationship and underlying mechanisms still need to be further clarified.

Causal effects of endometriosis on SLE, RA and SS risk: evidence from meta-analysis and Mendelian randomization

BACKGROUND

Endometriosis is an underdiagnosed disorder that affects an estimated 6-10% of women of reproductive age. Endometriosis has been reported in epidemiological studies to be associated with autoimmune diseases. However, the relationship remains controversial.

METHODS

A meta-analysis of observational studies was undertaken to evaluate the risk of autoimmune diseases in patients with endometriosis. The relevant studies were retrieved via the databases Medline, Embase and Web of Science until July 20, 2023. Mendelian randomization (MR) was subsequently utilized to scrutinize the causal influence of genetic predisposition toward endometriosis on three autoimmune diseases.

RESULTS

The meta-analysis findings revealed a relationship between endometriosis and the onset of SLE (cohort studies: RR = 1.77, 95% confidence interval (CI): 1.47-2.13, I2 = 0%; Case-control and cross-sectional studies: OR = 5.23, 95% CI: 0.74-36.98, I2 = 98%), RA (cohort studies: RR = 2.18, 95% CI: 1.85-2.55, I2 = 92%; Case-control and cross-sectional studies: OR = 1.40, 95% CI: 1.19-1.64, I2 = 0%) and SS (cohort studies: RR = 1.49, 95% CI: 1.34-1.66, I2 = 0%). Similarly, in our MR study, the results of the inverse-variance-weighted (IVW) model suggested that genetic predisposition to endometriosis was causally associated with an increased risk for SLE (OR = 1.915, 95% CI: 1.204-3.045, p = 0.006) and RA (OR = 1.005, 95% CI: 1.001-1.009, p = 0.014).

CONCLUSIONS

Both our meta-analysis and MR study indicate that endometriosis increases the risk of autoimmune diseases. These findings not only broaden our understanding of the genetic mechanisms underlying the comorbidity of endometriosis and autoimmune diseases, but also offer a new strategy for autoimmune disease prevention.

Serological autoimmune profile of systemic lupus erythematosus in deep and non-deep endometriosis patients

OBJECTIVE

Several studies have reported a high prevalence of autoimmune diseases such as systemic lupus erythematosus (SLE) in endometriosis patients. The aim of this study was to evaluate the SLE autoimmune antibody profile in patients with deep (DE) and non-deep endometriosis (Non-DE).

MATERIALS AND METHODS

Four groups of premenopausal patients were evaluated: patients with DE (n = 50); patients with ovarian endometriomas (Non-DE; n = 50); healthy patients without endometriosis (C group; n = 45); and SLE patients without endometriosis (SLE group; N = 46). Blood samples were obtained and the standard SLE autoimmune profile was evaluated in all patients. Pain symptoms related to endometriosis and clinical SLE manifestations were also recorded.

RESULTS

The DE group presented a statistically significant higher proportion of patients with antinuclear antibodies (ANA) (20%) compared to the Non-DE group (4%) and C group (2.2%). Levels of complement were more frequently lower among DE and Non-DE patients although differences did not reach statistical significance. Similarly, anti-dsDNA antibodies and anticoagulant lupus were positive in more patients of the DE group but did not reach statistical significance. The DE group complained of more arthralgia and asthenia compared to the Non-DE and C groups.

CONCLUSIONS

The results of this study showed higher positivity of ANA and greater arthralgia and asthenia in patients with DE compared with Non-DE patients and healthy controls, suggesting that they may have a higher susceptibility to autoimmune diseases and present more generalized pain.

Endometriosis diagnosis, staging and typology and adverse pregnancy outcome history

BACKGROUND

Women with endometriosis may have an increased risk of adverse pregnancy outcomes. Research has focused on infertility clinic populations limiting generalisability. Few studies report differences by endometriosis severity.

OBJECTIVES

We investigated the relationships between endometriosis diagnosis, staging and typology and pregnancy outcomes among an operative and population-based sample of women.

METHODS

Menstruating women ages 18-44 years enrolled in the ENDO Study (2007-2009), including the operative cohort: 316 gravid women undergoing laparoscopy/laparotomy at surgical centres in Utah and California; and the population cohort: 76 gravid women from the surgical centres' geographic catchment areas. Pregnancy outcomes were ascertained by questionnaire and included all pregnancies prior to study enrolment. Endometriosis was diagnosed via surgical visualisation in the operative cohort and pelvic magnetic resonance imaging in the population cohort. Adjusted prevalence ratios (aPR) and 95% confidence intervals (CI) were estimated using generalised linear mixed models for pregnancy outcomes, adjusting for women's age at study enrolment and at pregnancy, surgical site, body mass index and lifestyle factors.

RESULTS

Women in the operative cohort with visualised endometriosis (n = 109, 34%) had a lower prevalence of live births, aPR 0.94 (95% CI 0.85, 1.03) and a higher prevalence of miscarriages, aPR 1.48 (95% CI 1.23, 1.77) compared with women without endometriosis. The direction and magnitude of estimates were similar in the population cohort. Women with deep endometriosis were 2.98-fold more likely (95% CI 1.12, 7.95) to report a miscarriage compared with women without endometriosis after adjusting for women's age at study enrolment and at pregnancy, surgical site and body mass index. No differences were seen between endometriosis staging and pregnancy outcomes.

CONCLUSIONS

While there was no difference in number of pregnancies among women with and without endometriosis in a population-based sample, pregnancy loss was more common among women with endometriosis, notably among those with deep endometriosis.

Correlation between Endometriosis and Selected Allergic and Autoimmune Diseases and Eating Habits

Background and Objectives: Endometriosis is a hormone-dependent chronic inflammatory disease with serious reproductive and general health consequences. It is viewed as a multifactorial problem, consisting of matters related to altered immunity and genetics. In this study, we determined the correlation between endometriosis and allergic and autoimmune diseases in patients at reproductive age. Materials and Methods: Online surveys distributed through websites related to gynecological problems. The questionnaire was composed of 63 single and multiple-choice questions concerning the course of endometriosis, diet, and allergic and autoimmune diseases. The obtained data were assessed using statistical tests. Results: 501 female patients (mean age 31.1 SD = 6.8) were included in the study. The control group (n = 155) consisted of healthy females, whereas the study group (n = 346) consisted of female patients with endometriosis; each group was subdivided according to allergy status. There were statistically significant differences between groups for the following: positive family history of endometriosis (p = 0.0002), onset of allergic symptoms (p = 0.0003), frequency and duration of abdominal pain (p = 0.00625), and defecation disorders (p = 0.0006). Asthma was less common in the study group (p = 0.00611). The group of patients with endometriosis and allergies had a high median of consumption of red meat (p = 0.0143), fish (p = 0.0016), and dairy products (p = 0.0001). Conclusions: Endometriosis did not affect autoimmune diseases and their courses. Patients with diagnosed endometriosis presented allergy symptoms much earlier than the healthy patients. The consumption of dietary products such as soya products, red meat, and alcohol had an influence on the occurrence of endometriosis.

A Roadmap for Investigating Preclinical Autoimmunity Using Patient-Oriented and Epidemiologic Study Designs: Example of Rheumatoid Arthritis

Background & Aims

Rheumatoid arthritis (RA) is a prototypic autoimmune disease causing inflammatory polyarthritis that affects nearly 1% of the population. RA can lead to joint destruction and disability along with increased morbidity and mortality. Similar to other autoimmune diseases, RA has distinct preclinical phases corresponding to genetic risk, lifestyle risk factors, autoantibody development, and non-specific symptoms prior to clinical diagnosis. This narrative review will detail observational studies for RA risk and clinical trials for RA prevention as a roadmap to investigating preclinical autoimmunity that could be applied to other diseases.

Methods

In this narrative review, we summarized previous and ongoing research studies investigating RA risk and prevention, categorizing them related to their design and preclinical phases.

Results

We detailed the following types of studies investigating RA risk and prevention: retrospective population-based and administrative datasets; prospective studies (case-control and cohort; some enrolling based on genetics, first-degree relative status, elevated biomarkers, or early symptoms/arthritis); and randomized clinical trials. These correspond to all preclinical RA phases (genetic, lifestyle, autoimmunity, early signs/symptoms). Previous and ongoing randomized controlled trials have enrolled individuals at very elevated risk for RA based on biomarkers, symptoms, imaging abnormalities, or early signs/symptoms.

Conclusion

We detailed the rich variety of study designs that is necessary to investigate distinct preclinical phases of an autoimmune disease such as RA. However, further progress is needed to fully elucidate the pathogenesis of RA that may ultimately lead to prevention or delay of disease onset.