What is the impact of sex hormones on the pathogenesis of rheumatoid arthritis?

Sex hormone imbalance and rheumatoid arthritis in American men: a cross-sectional analysis from NHANES 2011-2016

Background

Emerging evidence suggests that sex hormones, particularly testosterone and sex hormone-binding globulin (SHBG), play a critical role in the pathophysiology of Rheumatoid arthritis (RA). However, the precise relationship between these hormonal factors and RA risk in men remains underexplored.

Methods

We conducted a cross-sectional analysis using data from the National Health and Nutrition Examination Survey (NHANES) 2011-2016. A total of 3,110 male participants were included after excluding those with missing data on testosterone, SHBG, RA, or key covariates. Serum testosterone and SHBG levels were measured, and RA status was determined based on self-reported physician diagnosis. Multivariate logistic regression models were used to assess the association between testosterone, SHBG, and RA. Restricted cubic spline (RCS) regression was applied to explore nonlinear relationships. Subgroup and interaction analyses were performed to assess effect modifications by age, race/ethnicity, body mass index (BMI), hypertension, and poverty-income ratio (PIR).

Results

Of the 3,110 men analyzed, 191 were diagnosed with RA. Low testosterone levels (<300 ng/dL) were significantly associated with increased RA risk (OR = 2.30, 95% CI: 1.65-3.21, p < 0.001), and elevated SHBG levels (>57 nmol/L) were also associated with a higher risk of RA (OR = 1.65, 95% CI: 1.14-2.39, p = 0.008). RCS analysis indicated a nonlinear relationship between testosterone, SHBG, and RA risk, with sharp increases in RA risk at the lower ends of testosterone and SHBG levels. Interaction analyses revealed that age, race/ethnicity, hypertension, and PIR significantly modified the relationship between these hormonal factors and RA, while BMI did not exhibit any significant interaction.

Conclusion

This study provides evidence that low testosterone and high SHBG levels are associated with an increased risk of RA in men. These associations are nonlinear and modified by factors such as age, race/ethnicity, hypertension, and PIR. Our findings highlight the importance of considering hormonal status in RA risk assessment and suggest potential avenues for targeted therapeutic strategies aimed at hormonal regulation.

Contraceptives or Hormone Replacement Therapy and Associations with Autoimmune Conditions: Exploring Effects of Estrogen Analog Supplementation

OBJECTIVE

The aim of this study was to investigate the impact of estrogen and progesterone analog supplementation on the development of autoimmune conditions.

METHODS

This retrospective observational study used data from the TriNetX network, which comprised over 100 million patients from 89 health care organizations. We compared patients exposed to estrogen and progesterone analogs to those exposed to progesterone-only therapy, using 1:1 propensity score matching based on age, ethnicity, and additional criteria. The primary outcomes were incidences of various autoimmune conditions.

RESULTS

We included 3,338,925 patients in the group who received estrogen and progesterone and 2,090,758 patients in the group who received progesterone only. Prematching, the group who received combined therapy showed increased risks for Sjögren disease (risk ratio [RR] 1.46), rheumatoid arthritis (RR 1.1), and other autoimmune conditions. Postmatching, significant associations persisted for most conditions, with increased risks for systemic sclerosis, systemic lupus erythematosus, giant cell arteritis, Behcet disease, psoriatic arthritis, reactive arthritis, and ankylosing spondylitis. The group who received combination therapy appeared to have lower risks of developing antiphospholipid syndrome (RR 0.7).

CONCLUSION

Combined estrogen and progesterone therapy is associated with an increased risk of several autoimmune conditions. The role of estrogen, despite its protective effects against some conditions, underscores the complex interplay of sex hormones in autoimmunity. Further prospective studies are needed to elucidate underlying mechanisms and evaluate causality.

Reproductive health and rheumatoid arthritis

INTRODUCTION

The prevalence of Rheumatoid Arthritis (RA) has been steadily increasing over the last thirty years, particularly among women. Due to the conflicting results of various studies on the link between rheumatoid arthritis and reproductive health, we have undertaken this study to explore their relationship.

METHODS

This cross-sectional study utilized primary data from5557 women involved in the Fasa Persian Cohort in the years 2013 to 2018. The study examined the frequency of RA and its association with various factors related to reproductive health, including age at first pregnancy, number of alive children, history of abortion, and infertility. SPSS software was utilized for data analysis, with the significance level set at p < 0.05.

RESULTS

5557 women with an average age of 48.6 ± 9.5 years participated. Of these women, 7.2% were diagnosed with rheumatoid disease, with an average onset age of 38.2 ± 15.2. The study did not find a significant correlation between RA and factors such as number of pregnancies, age at first pregnancy, duration of breastfeeding and number of children.

CONCLUSION

The study suggests that the experience of RA is independent of gynecological, obstetric factors, or reproductive life. This finding may provide reassurance to women affected by RA.

Sex Dimorphism in Pulmonary Arterial Hypertension Associated With Autoimmune Diseases

Pulmonary hypertension is a rare, incurable, and progressive disease. Although there is increasing evidence that immune disorders, particularly those associated with connective tissue diseases, are a strong predisposing factor in the development of pulmonary arterial hypertension (PAH), there is currently a lack of knowledge about the detailed molecular mechanisms responsible for this phenomenon. Exploring this topic is crucial because patients with an immune disorder combined with PAH have a worse prognosis and higher mortality compared with patients with other PAH subtypes. Moreover, data recorded worldwide show that the prevalence of PAH in women is 2× to even 4× higher than in men, and the ratio of PAH associated with autoimmune diseases is even higher (9:1). Sexual dimorphism in the pathogenesis of cardiovascular disease was explained for many years by the action of female sex hormones. However, there are increasing reports of interactions between sex hormones and sex chromosomes, and differences in the pathogenesis of cardiovascular disease may be controlled not only by sex hormones but also by sex chromosome pathways that are not dependent on the gonads. This review discusses the role of estrogen and genetic factors including the role of genes located on the X chromosome, as well as the potential protective role of the Y chromosome in sexual dimorphism, which is prominent in the occurrence of PAH associated with autoimmune diseases. Moreover, an overview of animal models that could potentially play a role in further investigating the aforementioned link was also reviewed.

What role do socioeconomic and clinical factors play in disease activity states in rheumatoid arthritis? Data from a large UK early inflammatory arthritis audit

BACKGROUND

Persistently active rheumatoid arthritis (pactiveRA) may be due to the interplay between biological and non-biological factors. The role of socioeconomic factors remains unclear.

OBJECTIVES

To explore which biological and non-biological factors associate with pactiveRA.

METHODS

Adults with early RA in the National Early Inflammatory Arthritis Audit, recruited from May 2018 to October 2022, were included if having pactiveRA or persistently low RA (plowRA). The pactiveRA was defined as three consecutive Disease Activity Score-28 joints (DAS28) of >3.2 at baseline, 3 and 12 months. The plowRA was defined as DAS28 ≤3.2 at 3 and 12 months. Stepwise forward logistic regression was used to explore associations with pactiveRA (outcome). Age and gender were included a priori, with socioeconomic factors and comorbidities as exposure variables.

RESULTS

682 patients with pactiveRA and 1026 plowRA were included. Compared with plowRA, patients with pactiveRA were younger (58, IQR: 49-67) versus (62, IQR: 52-72), and included more women (69% vs 59%). The pactiveRA was associated with worse scores in patient-reported outcomes at baseline, and anxiety and depression screens. Overall, there was clear social patterning in pactiveRA, with age-by-gender interaction. Logistic regression indicated age, gender, social deprivation and previous or current smoking, were independently associated with pactiveRA, after controlling for disease severity markers (seropositivity). Depression, lung disease, gastric ulcers and baseline corticosteroid use, were also associated with pactiveRA (p<0.05 for all).

CONCLUSION

Socioeconomic factors and deprivation were associated with pactiveRA, independent of clinical and disease characteristics. Identifying 'adverse' socioeconomic drivers of pactiveRA can help tailor interventions according to individual need.

Comprehensive insights into rheumatoid arthritis: Pathophysiology, current therapies and herbal alternatives for effective disease management

Rheumatoid arthritis is a chronic autoimmune inflammatory disease characterized by immune response overexpression, causing pain and swelling in the synovial joints. This condition is caused by auto-reactive antibodies that attack self-antigens due to their incapacity to distinguish between self and foreign molecules. Dysregulated activity within numerous signalling and immunological pathways supports the disease's development and progression, elevating its complexity. While current treatments provide some alleviation, their effectiveness is accompanied by a variety of adverse effects that are inherent in conventional medications. As a result, there is a deep-rooted necessity to investigate alternate therapeutic strategies capable of neutralizing these disadvantages. Medicinal herbs display a variety of potent bioactive phytochemicals that are effective in the complementary management of disease, thus generating an enormous potency for the researchers to delve deep into the development of novel phytomedicine against autoimmune diseases, although additional evidence and understanding are required in terms of their efficacy and pharmacodynamic mechanisms. This literature-based review highlights the dysregulation of immune tolerance in rheumatoid arthritis, analyses the pathophysiology, elucidates relevant signalling pathways involved, evaluates present and future therapy options and underscores the therapeutic attributes of a diverse array of medicinal herbs in addressing this severe disease.

Arthritis alleviation: unveiling the potential in Abrus precatorius macerated oil

Aim: This study endeavors to explore the anti-arthritic effects of macerated oil derived from the plant's aerial parts. Methods: The macerated oil was prepared using maceration in coconut oil, and its phytochemical composition was elucidated using GC-MS. To assess its anti-arthritic activity, in-vitro studies were conducted using various assays. Results & conclusion: The macerated oil showed better antioxidant and anti-arthritic potential by in-vitro investigations. Molecular docking studies elucidated potential binding interactions between specific constituents of the oil and critical molecular targets implicated in the pathogenesis of arthritis, further substantiating its therapeutic potential. The results demonstrated that Abrus precatorius macerated oil could ameliorate arthritis severity in a dose-dependent manner.

Hormonal and reproductive factors in relation to the risk of rheumatoid arthritis in women: a prospective cohort study with 223 526 participants

OBJECTIVE

This study aimed to examine rheumatoid arthritis (RA) risk associated with hormonal and reproductive factors in women from the large cohort of the UK Biobank.

METHODS

Data on hormonal and reproductive factors in women were collected from a prospective cohort of 223 526 UK Biobank participants. The potential relationship between reproductive factors and RA risk was assessed using restricted cubic spline. Hazard ratios (HR) were estimated using Cox proportional hazard regressions.

RESULTS

During a median follow-up of 12.39 years, 3313 women with RA were identified. Age at menarche >14 years was associated with a greater RA risk (HR 1.13, 95% CI 1.02 to 1.26) compared with menarche at 13. The multiple adjusted HR for RA in women with menopause at <45 years was 1.46. Reproductive years <33 increased the risk of RA (HR 1.39, 95% CI 1.21 to 1.59). Compared with those with 2 children, women with ≥4 children were associated with a higher risk of RA (HR 1.18, 95% CI 1.04 to 1.34). Women who had a hysterectomy (HR 1.40, 95% CI 1.25 to 1.56) or oophorectomy (HR 1.21, 95% CI 1.08 to 1.35) had a higher risk of RA than those without a hysterectomy or oophorectomy. Both hormone replacement therapy (HRT) use (HR 1.46, 95% CI 1.35 to 1.57) and HRT duration (HR 1.02, 95% CI 1.01 to 1.03) were associated with a higher risk of RA.

CONCLUSIONS

Some hormonal and reproductive factors were associated with a higher risk of RA. Hormonal and reproductive factors should be considered in risk assessment and formulating management plans in female patients with RA.

Epidemiology and Risk Factors for Rheumatoid Arthritis Development

Rheumatoid arthritis (RA) is a prevalent chronic inflammatory arthritis worldwide, significantly impacting patients and population health. The disease affects women primarily, with a female-to-male ratio of three to one. Its pathogenesis is multifactorial, including genetic and environmental risk factors. Epidemiological studies highlight the link between the environment and genetic susceptibility to RA. The so-called shared epitope is the most significant risk factor that seems to act synergetic with other environmental factors in the disease occurrence. In addition, recent findings suggest a potential role of new substantial environmental factors, such as the observed pollution of the planet's natural resources, on the susceptibility and progression of the disease. This review summarises the most decisive evidence on epidemiology and genetic, environmental, and lifestyle risk factors for RA. It shows that studying genetic and environmental factors in correlation could lead to prevention strategies that may impact the natural history of the disease.

Applications and recent advances in transdermal drug delivery systems for the treatment of rheumatoid arthritis

Rheumatoid arthritis is a chronic, systemic autoimmune disease predominantly based on joint lesions with an extremely high disability and deformity rate. Several drugs have been used for the treatment of rheumatoid arthritis, but their use is limited by suboptimal bioavailability, serious adverse effects, and nonnegligible first-pass effects. In contrast, transdermal drug delivery systems (TDDSs) can avoid these drawbacks and improve patient compliance, making them a promising option for the treatment of rheumatoid arthritis (RA). Of course, TDDSs also face unique challenges, as the physiological barrier of the skin makes drug delivery somewhat limited. To overcome this barrier and maximize drug delivery efficiency, TDDSs have evolved in terms of the principle of transdermal facilitation and transdermal facilitation technology, and different generations of TDDSs have been derived, which have significantly improved transdermal efficiency and even achieved individualized controlled drug delivery. In this review, we summarize the different generations of transdermal drug delivery systems, the corresponding transdermal strategies, and their applications in the treatment of RA.

Temporomandibular joint involvement in elderly onset and young onset rheumatoid arthritis patients

OBJECTIVE

There are studies showing clinical and laboratory differences between elderly-onset rheumatoid arthritis and young-onset rheumatoid arthritis. Temporomandibular joint involvement in rheumatoid arthritis is not rare. In this study, we aimed to examine the temporomandibular joint involvement and magnetic resonance imaging findings in elderly-onset rheumatoid arthritis and young-onset rheumatoid arthritis patients.

METHODS

A total of 87 rheumatoid arthritis patients were investigated retrospectively. The onset ≥60 years was considered elderly-onset rheumatoid arthritis. Erosion, flattening, and resorption of the condyle, narrowing of the joint space, joint effusion, synovial hypertrophy, and synovitis were interpreted as temporomandibular joint involvement with magnetic resonance imaging. Patients' age, gender, rheumatoid factor, and anti-cyclic citrullinated peptide positivity, extra-articular findings, medical treatment, and disease activity score were noted.

RESULTS

A total of 15 (17.2%) patients had elderly-onset rheumatoid arthritis. Temporomandibular joint involvement was detected in 67 (77%) patients; 9 (60%) of them were in the elderly-onset rheumatoid arthritis group (n=15) and 58 (80.6%) of them were in the young-onset rheumatoid arthritis group (n=72). Patients with temporomandibular joint involvement were significantly higher than those without temporomandibular joint involvement in both the elderly-onset rheumatoid arthritis and young-onset rheumatoid arthritis groups (p<0.001). No significant difference was found between elderly-onset rheumatoid arthritis and young-onset rheumatoid arthritis for the temporomandibular joint involvement (p=0.100). In the young-onset rheumatoid arthritis group, rheumatoid factor positivity and anti-cyclic citrullinated peptide positivity were more frequent in the patients with temporomandibular joint involvement (p=0.011, p=0.024). A comparison of the elderly-onset rheumatoid arthritis and young-onset rheumatoid arthritis patients showed no significant difference in the magnetic resonance imaging findings except for the resorption of the condyle.

CONCLUSION

According to our findings, elderly-onset rheumatoid arthritis is not much different from young-onset rheumatoid arthritis in terms of temporomandibular joint involvement, magnetic resonance imaging findings, and clinical and laboratory features.

Triterpenes as Potential Drug Candidates for Rheumatoid Arthritis Treatment

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease characterized by joint inflammation, swelling and pain. Although RA mainly affects the joints, the disease can also have systemic implications. The presence of autoantibodies, such as anti-cyclic citrullinated peptide antibodies and rheumatoid factors, is a hallmark of the disease. RA is a significant cause of disability worldwide associated with advancing age, genetic predisposition, infectious agents, obesity and smoking, among other risk factors. Currently, RA treatment depends on anti-inflammatory and disease-modifying anti-rheumatic drugs intended to reduce joint inflammation and chronic pain, preventing or slowing down joint damage and disease progression. However, these drugs are associated with severe side effects upon long-term use, including immunosuppression and development of opportunistic infections. Natural products, namely triterpenes with anti-inflammatory properties, have shown relevant anti-arthritic activity in several animal models of RA without undesirable side effects. Therefore, this review covers the recent studies (2017-2022) on triterpenes as safe and promising drug candidates for the treatment of RA. These bioactive compounds were able to produce a reduction in several RA activity indices and immunological markers. Celastrol, betulinic acid, nimbolide and some ginsenosides stand out as the most relevant drug candidates for RA treatment.

Sex and gender in infection and immunity: addressing the bottlenecks from basic science to public health and clinical applications

Although sex and gender are recognized as major determinants of health and immunity, their role is rarely considered in clinical practice and public health. We identified six bottlenecks preventing the inclusion of sex and gender considerations from basic science to clinical practice, precision medicine and public health policies. (i) A terminology-related bottleneck, linked to the definitions of sex and gender themselves, and the lack of consensus on how to evaluate gender. (ii) A data-related bottleneck, due to gaps in sex-disaggregated data, data on trans/non-binary people and gender identity. (iii) A translational bottleneck, limited by animal models and the underrepresentation of gender minorities in biomedical studies. (iv) A statistical bottleneck, with inappropriate statistical analyses and results interpretation. (v) An ethical bottleneck posed by the underrepresentation of pregnant people and gender minorities in clinical studies. (vi) A structural bottleneck, as systemic bias and discriminations affect not only academic research but also decision makers. We specify guidelines for researchers, scientific journals, funding agencies and academic institutions to address these bottlenecks. Following such guidelines will support the development of more efficient and equitable care strategies for all.

Frequency of osteoporosis in Chinese patients with rheumatoid arthritis: a meta-analysis

OBJECTIVE

To evaluate the current frequency of osteoporosis (OP) in Chinese patients with rheumatoid arthritis (RA) through meta-analysis.

METHODS

The databases of PubMed, Web of Science, Cochrane Library, CNKI, Wan Fang, CBM, and VIP were searched for relevant literature regarding the occurrence of OP in Chinese patients with RA from January 1, 2000, to September 15, 2022. The literature was screened using inclusion and exclusion criteria, and qualifying articles were subjected to data extraction, quality evaluation, and meta-analysis using Stata 17.0 software.

RESULTS

Altogether, 44 publications were included in this study, with a total sample size of 12,264 RA cases and 4532 patients with OP. Meta-analysis revealed that the frequency of OP in patients with RA was 37.67% [95% CI: 34.38%, 40.97%], while subgroup analysis showed that the frequency in South China was 49.43% [95% CI: 40.53%, 58.32%]. Also, the frequency in men was 29.29% [95% CI: 22.42%, 36.16%], which was significantly lower than in women (41.89% [95% CI: 36.87%, 46.90%]). The incidence rate in pre-menopausal women was only 15.19% [95% CI: 8.79%, 21.59%], much lower than the figure of 54.29% [95% CI: 45.28%, 63.30%] for post-menopausal women. Additionally, the frequency rates in the low, intermediate, and high disease activity groups were 24.52% [95% CI: 11.52%, 37.52%)], 27.67% [95% CI: 13.50%, 41.85%], and 57.96% [95% CI: 37.35%, 78.56%], respectively.

CONCLUSION

The frequency of OP in the Chinese RA population is higher than the world average, and patients with RA should receive standardized anti-RA therapy at an early stage, with emphasis on bone health in postmenopausal women, patients with high disease activity or longer disease duration.

Sex bias in lymphocytes: Implications for autoimmune diseases

Autoimmune diseases are characterized by a significant sex dimorphism, with women showing increased susceptibility to disease. This is, at least in part, due to sex-dependent differences in the immune system that are influenced by the complex interplay between sex hormones and sex chromosomes, with contribution from sociological factors, diet and gut microbiota. Sex differences are evident in the number and function of lymphocyte populations. Women mount a stronger pro-inflammatory response than males, with increased lymphocyte proliferation, activation and pro-inflammatory cytokine production, whereas men display expanded regulatory cell subsets. Ageing alters the immune landscape of men and women in differing ways, resulting in changes in autoimmune disease susceptibility. Here we review the current literature on sex differences in lymphocyte function, the factors that influence this, and the implications for autoimmune disease. We propose that improved understanding of sex bias in lymphocyte function can provide sex-specific tailoring of treatment strategies for better management of autoimmune diseases.