Could sex-specific subtypes of hand osteoarthritis exist? A retrospective study in women presenting to secondary care

Introduction

Hand osteoarthritis is more common in women, and its risk increases around the time of the menopause. We set out to describe the timing between menopause and the onset of symptomatic hand osteoarthritis (OA), and associations with the use of hormone replacement therapy (HRT) or its discontinuation, describing any identifiable subgroups of women.

Methods

Retrospective healthcare-records study of sequential women referred to a specialist hand OA clinic, 2007-2015. Confirmation of hand OA diagnosis was by clinican, by accepted criteria. Demographics and clinical variables were from healthcare-records, recorded by standardised proforma. Outcomes of interest were reported age of onset of hand symptoms, reported age at final menstrual period (FMP), time from FMP to reported onset of hand symptoms and time from cessation of HRT to reported onset of hand symptoms. Exposure categories for systemic HRT use were never users, current users, previous users. Analysis of Variance compared groups; linear regression analysed associations of exposure with outcome.

Results

82/92(89%) of eligible women were post-menopausal, mean age at FMP 49.9 years (SD5.4). In these post-menopausal women, median time from FMP to hand symptom onset was 3 years. 48/82 (59%) developed hand symptoms within the defined peri-menopausal period (FMP ± 4 years), whilst some women developed their symptoms before or after (range -25, 30 years). In women who discontinued HRT prior to symptom onset, the median time from HRT cessation to onset of hand symptoms was 6 months. Past HRT users were older at hand symptom onset than women who had not taken HRT [coeff.4.7 years (0.92, 8.39); P = 0.015].

Conclusions

This study adds to evidence associating the menopause/sex hormone deficiency with hand OA symptom onset in a sizeable subgroup of women (but not all). HRT use/cessation appears to influence the timing of onset of hand OA symptoms. It is not possible to interpret from this type of study whether sex hormone deficiency is causative of disease or modulates its symptoms. It is also not possible to judge whether painful hand osteoarthritis in post-menopausal women is a subtype of disease. Further investigation is indicated of sex-specific subtypes and potential for personalised medicine for post-menopausal women with hand osteoarthritis, as a clearly definable high-risk subgroup.

Hysterectomy and risk of osteoarthritis in women: a nationwide nested case-control study

OBJECTIVE

Hysterectomy is the most common gynaecological surgery, performed mainly for benign uterine pathologies in women. Studies have suggested that hysterectomy is associated with osteoarthritis (OA); however, the association remains controversial. This study aimed to investigate the association between hysterectomy and the risk of OA.

METHOD

We performed a population-based nested case-control study using the National Health Insurance programme database from 2000 to 2016 in Taiwan. All medical conditions for each case and control were categorized using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) and ICD-10. A multiple conditional logistic regression model was applied to analyse the adjusted odds ratio (aOR) and 95% confidence interval (CI) for the association between hysterectomy and OA.

RESULTS

Our analyses included 16 592 patients with OA and 66 368 matched controls. After adjustment for possible confounders, hysterectomy had a significant association with OA (aOR = 1.19, 95% CI = 1.09-1.30), especially knee OA (aOR = 1.25, 95% CI = 1.13-1.38). Furthermore, women who received oestrogen therapy (ET) alone and patients who underwent hysterectomy without ET showed a greater risk of OA development compared to women who did not receive ET (aOR = 1.14, 95% CI = 1.07-1.23, and aOR = 1.19, 95% CI = 1.08-1.31, respectively).

CONCLUSION

Our findings indicate that hysterectomy is associated with OA, especially knee OA. We also found that women who received ET alone and patients who underwent hysterectomy without ET had an increased risk of OA.

The influence of sex hormones on musculoskeletal pain and osteoarthritis

The association of female sex with certain rheumatic symptoms and diseases is now indisputable. Some of the most striking examples of this association occur in individuals with musculoskeletal pain and osteoarthritis, in whom sex-dependent changes in incidence and prevalence of disease are seen throughout the lifecourse. Joint and muscle pain are some of the most common symptoms of menopause, and there is increasingly compelling evidence that changes in or loss of sex hormones (be it natural, autoimmune, pharmacological, or surgical) influence musculoskeletal pain propensity and perhaps disease. However, the effects of modulation or replacement of sex hormones in this context are far less established, particularly whether these approaches could represent a preventative or therapeutic opportunity once symptoms have developed. In this Review, we present evidence for the association of changes in sex hormones with musculoskeletal pain and painful osteoarthritis, discussing data from diverse natural, therapeutic, and experimental settings in humans and relevant animal models relating to hormone loss or replacement and the consequent effects on health, pain, and disease. We also postulate mechanisms by which sex hormones could mediate these effects. Further research is needed; however, increased scientific understanding of this complex area could lead to real benefits in musculoskeletal and women's health.

Uncovering the "riddle of femininity" in osteoarthritis: a systematic review and meta-analysis of menopausal animal models and mathematical modeling of estrogen treatment

OBJECTIVE

Post-menopausal women are disproportionately affected by osteoarthritis (OA). As such, the purpose of this study was to (1) summarize the state-of-the-science aimed at understanding the effects of menopause on OA in animal models and (2) investigate how dosage and timing of initiation of estrogen treatment affect cartilage degeneration.

DESIGN

A systematic review identified articles studying menopausal effects on cartilage in preclinical models. A meta-analysis was performed using overlapping cartilage outcomes in conjunction with a rigor and reproducibility analysis. Ordinary differential equation models were used to determine if a relationship exists between cartilage degeneration and the timing of initiation or dosage of estrogen treatment.

RESULTS

Thirty-eight manuscripts were eligible for inclusion. The most common menopause model used was ovariectomy (92%), and most animals were young at the time of menopause induction (86%). Most studies did not report inclusion criteria, animal monitoring, protocol registration, or data accessibility. Cartilage outcomes were worse in post-menopausal animals compared to age-matched, non-menopausal animals, as evidenced by cartilage histological scoring [0.75, 1.72], cartilage thickness [-4.96, -0.96], type II collagen [-4.87, -0.56], and c-terminal cross-linked telopeptide of type II collagen (CTX-II) [2.43, 5.79] (95% CI of Effect Size (+greater in menopause, -greater in non-menopause)). Moreover, modeling suggests that cartilage health may be improved with early initiation and higher doses of estrogen treatment.

CONCLUSIONS

To improve translatability, animal models that consider aging and natural menopause should be utilized, and more attention to rigor and reproducibility is needed. Timing of initiation and dosage may be important factors modulating therapeutic effects of estrogen on cartilage.

Osteoarthritis: The importance of hormonal status in midlife women

Osteoarthritis (OA) is the commonest joint condition globally, affecting 18 % of women over the age of 60 years, although the prevalence varies according to the definition used. Although it may develop in any joint, it most commonly affects joints of the knee, hip, hand, spine and foot. Because OA often emerges in women in midlife, there has been longstanding interest in the association between hormonal status and the development and progression of OA. Researchers have variably suggested that estrogen exposure may be a risk factor for OA development, or that, conversely, it may be used as a therapy to treat OA. This review considers the historical development of this question, first described in the literature in 1805, and highlights the need for future research in this area.

Estrogen alleviates post-traumatic osteoarthritis progression and decreases p-EGFR levels in female mouse cartilage

Objective

To investigate the effect of estrogen on the progression of post-traumatic osteoarthritis (PTOA) in mice and its possible mechanism.

Methods

Twelve-week-old ICR mice were divided into Group A (female control group), group B (ovariectomized(OVX) group), group C (OVX group supplemented with estrogen), and group D (male group) by destabilization of the medial meniscus (DMM)or sham operation. Safranin O staining was performed at 8 weeks and 12 weeks after operation, and the degree of articular cartilage lesion was evaluated using Mankin score. Twelve weeks after the operation, tissue sections were stained to analyze the matrix metalloproteinase 13(MMP13), phosphorylated epidermal growth factor receptor (p-EGFR) expression and apoptosis of chondrocytes.

Results

Decreased estrogen can significantly increase the weight of mice in female mice. The degree of cartilage damage in the knee joint on the DMM side of female mice was significantly severer than that on the Sham side. The DMM side also showed higher MMP13 expression and increased apoptotic chondrocytes. The degree of cartilage damage in the knee joint on the DMM side of female mice was significantly reduced after estrogen supplementation, and cartilage damage in the knee joint on the DMM side of female mice was less serious than that of male mice. As estrogen levels decreased, the severity of cartilage erosion in the knee joint on the DMM side was aggravated, and p-EGFR expression in the cartilage surface was also higher in female mice contrast to that in male mice. However, minimal changes in p-EGFR expression in the cartilage surface of bilateral knee joints of male mice were observe.

Conclusion

Estrogen has a regulatory effect on PTOA and its inhibits the expression of p-EGFR in cartilage on the knee joint surface and has a protective effect on articular cartilage in female mice.

Orthobiologics for the Management of Early Arthritis in the Middle-Aged Athlete

This article is dedicated to the use of orthobiologic therapies in the management of early osteoarthritis in middle-aged athletes. Understanding a patient's presenting symptoms, physical examination, imaging results, and goals is of critical importance in applying orthobiologic therapies. The field of orthobiologics is expanding at a rapid pace, and the clinical studies examining the utility of each treatment lag behind the direct-to-consumer marketing that leads to these products being used. Here we provide a review of the available treatments, emerging treatments, and the current literature supporting or refuting their use. Currently studied orthobiologics include autologous and allogenic cell therapies, autologous blood products, hyaluronic acid, gene therapies, Wnt inhibitors, and a variety of systemic treatments.

Estrogen receptor Alpha in human knee articular cartilage of healthy and osteoarthritic females

Objective

Estrogen and osteoarthritis association has previously been proposed. This study evaluates the presence of estrogen receptors (ER)-α in articular cartilage, and its association.

Methods

A prospective cohort study of women undergoing anterior cruciate ligament reconstruction (controls) or total knee arthroplasty (cases) was performed. Cartilage samples were processed and ER-α expression was quantified.

Results

Twenty patients were included: 12 cases and 8 controls. ER-α expression was higher in the case subjects.

Conclusion

Increased ER-α expression is associated with age, and degeneration. This suggests estrogen deficiency is a risk for osteoarthritis and is inversely related to proliferative looking chondrocytes.

Menopausal hormone therapy and women's health: An umbrella review

BACKGROUND

There remains uncertainty about the impact of menopausal hormone therapy (MHT) on women's health. A systematic, comprehensive assessment of the effects on multiple outcomes is lacking. We conducted an umbrella review to comprehensively summarize evidence on the benefits and harms of MHT across diverse health outcomes.

METHODS AND FINDINGS

We searched MEDLINE, EMBASE, and 10 other databases from inception to November 26, 2017, updated on December 17, 2020, to identify systematic reviews or meta-analyses of randomized controlled trials (RCTs) and observational studies investigating effects of MHT, including estrogen-alone therapy (ET) and estrogen plus progestin therapy (EPT), in perimenopausal or postmenopausal women in all countries and settings. All health outcomes in previous systematic reviews were included, including menopausal symptoms, surrogate endpoints, biomarkers, various morbidity outcomes, and mortality. Two investigators independently extracted data and assessed methodological quality of systematic reviews using the updated 16-item AMSTAR 2 instrument. Random-effects robust variance estimation was used to combine effect estimates, and 95% prediction intervals (PIs) were calculated whenever possible. We used the term MHT to encompass ET and EPT, and results are presented for MHT for each outcome, unless otherwise indicated. Sixty systematic reviews were included, involving 102 meta-analyses of RCTs and 38 of observational studies, with 102 unique outcomes. The overall quality of included systematic reviews was moderate to poor. In meta-analyses of RCTs, MHT was beneficial for vasomotor symptoms (frequency: 9 trials, 1,104 women, risk ratio [RR] 0.43, 95% CI 0.33 to 0.57, p < 0.001; severity: 7 trials, 503 women, RR 0.29, 95% CI 0.17 to 0.50, p = 0.002) and all fracture (30 trials, 43,188 women, RR 0.72, 95% CI 0.62 to 0.84, p = 0.002, 95% PI 0.58 to 0.87), as well as vaginal atrophy (intravaginal ET), sexual function, vertebral and nonvertebral fracture, diabetes mellitus, cardiovascular mortality (ET), and colorectal cancer (EPT), but harmful for stroke (17 trials, 37,272 women, RR 1.17, 95% CI 1.05 to 1.29, p = 0.027) and venous thromboembolism (23 trials, 42,292 women, RR 1.60, 95% CI 0.99 to 2.58, p = 0.052, 95% PI 1.03 to 2.99), as well as cardiovascular disease incidence and recurrence, cerebrovascular disease, nonfatal stroke, deep vein thrombosis, gallbladder disease requiring surgery, and lung cancer mortality (EPT). In meta-analyses of observational studies, MHT was associated with decreased risks of cataract, glioma, and esophageal, gastric, and colorectal cancer, but increased risks of pulmonary embolism, cholelithiasis, asthma, meningioma, and thyroid, breast, and ovarian cancer. ET and EPT had opposite effects for endometrial cancer, endometrial hyperplasia, and Alzheimer disease. The major limitations include the inability to address the varying effects of MHT by type, dose, formulation, duration of use, route of administration, and age of initiation and to take into account the quality of individual studies included in the systematic reviews. The study protocol is publicly available on PROSPERO (CRD42017083412).

CONCLUSIONS

MHT has a complex balance of benefits and harms on multiple health outcomes. Some effects differ qualitatively between ET and EPT. The quality of available evidence is only moderate to poor.

Hand Osteoarthritis: investigating Pain Effects of estrogen-containing therapy (HOPE-e): a protocol for a feasibility randomised placebo-controlled trial

BACKGROUND

Hand osteoarthritis (OA) is a common condition, causing pain, stiffness and reduced quality of life. Incidence is higher amongst women, particularly around the age of the menopause. Whilst the relationship between sex hormones and OA has been studied in vitro, in epidemiological studies and in clinical trials of hormone replacement therapy (HRT), this study is the first to investigate the effect of estrogen-containing therapy on hand pain in post-menopausal women with symptomatic hand OA in a randomised study design.

METHODS

This is a feasibility study of a double-blinded placebo-controlled intervention with 1:1 randomisation to either a combination of conjugated estrogens 0.45 mg and bazedoxifene acetate 20 mg (Duavive) or placebo. The target population is post-menopausal women with symptomatic hand OA, aiming to recruit 60-90 study participants. The primary objective is to assess the feasibility of a future fully powered randomised controlled trial (RCT). Participants will take the study medication for 24 weeks and be followed up for 28 weeks after randomisation. The primary outcomes used to determine feasibility are eligible participant identification rates and routes; recruitment, randomisation and retention rates of eligible participants; study medication compliance; and the likelihood of unintentional unblinding. Secondary outcomes include measures of hand pain, function, appearance and menopausal symptoms. An end of study questionnaire and focus groups will help to refine the final protocol for a full study.

DISCUSSION

Identifying new treatments for symptomatic hand OA is a recognised research priority. The study will help us to understand whether there are sufficient interested and eligible individuals in this target population who would consider HRT for their hand symptoms. It will provide proof-of-concept RCT data on the effects of HRT on hand pain and other clinically relevant outcomes in this population. The study will gain valuable information on the feasibility of a full RCT and how best to run this. The findings will be published in a peer-reviewed journal and presented at a relevant conference.

TRIAL REGISTRATION

ISRCTN12196200 registered on 15 January 2019.

A molecular quantitative trait locus map for osteoarthritis

Osteoarthritis causes pain and functional disability for over 500 million people worldwide. To develop disease-stratifying tools and modifying therapies, we need a better understanding of the molecular basis of the disease in relevant tissue and cell types. Here, we study primary cartilage and synovium from 115 patients with osteoarthritis to construct a deep molecular signature map of the disease. By integrating genetics with transcriptomics and proteomics, we discover molecular trait loci in each tissue type and omics level, identify likely effector genes for osteoarthritis-associated genetic signals and highlight high-value targets for drug development and repurposing. These findings provide insights into disease aetiopathology, and offer translational opportunities in response to the global clinical challenge of osteoarthritis.

Does Pain at an Earlier Stage of Chondropathy Protect Female Mice Against Structural Progression After Surgically Induced Osteoarthritis?

OBJECTIVE

Female C57BL/6 mice exhibit less severe chondropathy than male mice. This study was undertaken to test the robustness of this observation and explore underlying mechanisms.

METHODS

Osteoarthritis was induced in male and female C57BL/6 or DBA/1 mice (n = 6-15 per group) by destabilization of the medial meniscus (DMM) or partial meniscectomy (PMX). Some mice were ovariectomized (OVX) (n = 30). In vivo repair after focal cartilage defect or joint immobilization (sciatic neurectomy) following DMM was assessed. Histologic analysis, evaluation of gene expression in whole knees, and behavioral analysis using Laboratory Animal Behavior Observation Registration and Analysis System (LABORAS) and Linton incapacitance testing (n = 7-10 mice per group) were performed.

RESULTS

Female mice displayed less severe chondropathy (20-75% reduction) across both strains and after both surgeries. Activity levels after PMX were similar for male and female mice. Some repair-associated genes were increased in female mouse joints after surgery, but no repair differences were evident in vivo. Despite reduced chondropathy, female mice developed pain-like behavior at the same time as male mice. At the time of established pain-like behavior (10 weeks after PMX), pain-associated genes were significantly up-regulated in female mice, including Gdnf (mean ± SEM fold change 2.54 ± 0.30), Nrtn (6.71 ± 1.24), Ntf3 (1.92 ± 0.27), and Ntf5 (2.89 ± 0.48) (P < 0.01, P < 0.01, P < 0.05, and P < 0.001, respectively, versus male mice). Inflammatory genes were not regulated in painful joints in mice of either sex.

CONCLUSION

We confirm strong structural joint protection in female mice that is not due to activity or intrinsic repair differences. Female mice develop pain at the same time as males, but induce a distinct set of neurotrophins. We speculate that heightened pain sensitivity in female mice protects the joint by preventing overuse.

Risk of hand osteoarthritis in new users of hormone replacement therapy: A nested case-control analysis

OBJECTIVE

To estimate the risk of hand osteoarthritis (HOA) associated with hormone replacement therapy (HRT).

METHODS

We conducted a nested case-control study using data from the UKbased Clinical Practice Research Datalink (1998-2017). In the study inception cohort comprised women at age 45. We matched women with incident HOA during follow-up (cases) to osteoarthritisfree controls on age and calendar date (index date, ID), in a ratio of 1:4. We applied conditional logistic regression to calculate odds ratios (OR) with 95 % confidence intervals (CI) of HOA associated with new HRT use compared with non-use overall, and for women with recorded menopause we calculated separate ORs according to the time between menopause and HRT initiation (current users), and the time between HRT cessation and the ID (past users), versus non-users.

RESULTS

There were 3440 cases and 13,760 controls (mean age: 50.9 ± 4.1 years). We observed an adjusted OR (aOR) of HOA of 1.32 (95 % CI 1.17-1.48) in HRT users (versus nonusers), which attenuated to 0.98 (95 % CI 0.85-1.14) in women with recorded menopause. Current users (versus nonusers) who initiated HRT 3 months before or after menopause had an aOR of 0.72 (95 % CI 0.55-0.96), while aORs increased with later HRT initiation. Among past users (versus non-users), we observed an aOR of 1.25 (95 % CI 0.86-1.81) when HRT use was stopped ≤18 months before the ID, approaching the null with increasing duration between HRT cessation and the ID.

CONCLUSION

Current HRT use was associated with a decreased risk of HOA if initiated around menopause, but the risk reduction disappeared after HRT cessation.

Investigational drugs for the treatment of osteoarthritis, an update on recent developments

INTRODUCTION

Osteoarthritis (OA) is the leading cause of pain, loss of function, and disability among elderly, with the knee the most affected joint. It is a heterogeneous condition characterized by complex and multifactorial etiologies which contribute to the broad variation in symptoms presentation and treatment responses that OA patients present. This poses a challenge for the development of effective treatment on OA.

AREAS COVERED

This review will discuss recent development of agents for the treatment of OA, updating our previous narrative review published in 2015. They include drugs for controlling local and systemic inflammation, regulating articular cartilage, targeting subchondral bone, and relieving pain.

EXPERT OPINION

Although new OA drugs such as monoclonal antibodies have shown marked effects and favorable tolerance, current treatment options for OA remain limited. The authors believe there is no miracle drug that can be used for all OA patients'; treatment and disease stage is crucial for the effectiveness of drugs. Therefore, early diagnosis, phenotyping OA patients and precise therapy would expedite the development of investigational drugs targeting at symptoms and disease progression of OA.

The 2017 hormone therapy position statement of The North American Menopause Society

The 2017 Hormone Therapy Position Statement of The North American Menopause Society (NAMS) updates the 2012 Hormone Therapy Position Statement of The North American Menopause Society and identifies future research needs. An Advisory Panel of clinicians and researchers expert in the field of women's health and menopause was recruited by NAMS to review the 2012 Position Statement, evaluate new literature, assess the evidence, and reach consensus on recommendations, using the level of evidence to identify the strength of recommendations and the quality of the evidence. The Panel's recommendations were reviewed and approved by the NAMS Board of Trustees.Hormone therapy (HT) remains the most effective treatment for vasomotor symptoms (VMS) and the genitourinary syndrome of menopause (GSM) and has been shown to prevent bone loss and fracture. The risks of HT differ depending on type, dose, duration of use, route of administration, timing of initiation, and whether a progestogen is used. Treatment should be individualized to identify the most appropriate HT type, dose, formulation, route of administration, and duration of use, using the best available evidence to maximize benefits and minimize risks, with periodic reevaluation of the benefits and risks of continuing or discontinuing HT.For women aged younger than 60 years or who are within 10 years of menopause onset and have no contraindications, the benefit-risk ratio is most favorable for treatment of bothersome VMS and for those at elevated risk for bone loss or fracture. For women who initiate HT more than 10 or 20 years from menopause onset or are aged 60 years or older, the benefit-risk ratio appears less favorable because of the greater absolute risks of coronary heart disease, stroke, venous thromboembolism, and dementia. Longer durations of therapy should be for documented indications such as persistent VMS or bone loss, with shared decision making and periodic reevaluation. For bothersome GSM symptoms not relieved with over-the-counter therapies and without indications for use of systemic HT, low-dose vaginal estrogen therapy or other therapies are recommended.This NAMS position statement has been endorsed by Academy of Women's Health, American Association of Clinical Endocrinologists, American Association of Nurse Practitioners, American Medical Women's Association, American Society for Reproductive Medicine, Asociación Mexicana para el Estudio del Climaterio, Association of Reproductive Health Professionals, Australasian Menopause Society, Chinese Menopause Society, Colegio Mexicano de Especialistas en Ginecologia y Obstetricia, Czech Menopause and Andropause Society, Dominican Menopause Society, European Menopause and Andropause Society, German Menopause Society, Groupe d'études de la ménopause et du vieillissement Hormonal, HealthyWomen, Indian Menopause Society, International Menopause Society, International Osteoporosis Foundation, International Society for the Study of Women's Sexual Health, Israeli Menopause Society, Japan Society of Menopause and Women's Health, Korean Society of Menopause, Menopause Research Society of Singapore, National Association of Nurse Practitioners in Women's Health, SOBRAC and FEBRASGO, SIGMA Canadian Menopause Society, Società Italiana della Menopausa, Society of Obstetricians and Gynaecologists of Canada, South African Menopause Society, Taiwanese Menopause Society, and the Thai Menopause Society. The American College of Obstetricians and Gynecologists supports the value of this clinical document as an educational tool, June 2017. The British Menopause Society supports this Position Statement.

Are estrogen-related drugs new alternatives for the management of osteoarthritis?

Osteoarthritis (OA) is a chronic degenerative disease involving multiple physiopathological mechanisms. The increased prevalence of OA after menopause and the presence of estrogen receptors in joint tissues suggest that estrogen could help prevent development of OA. This review summarizes OA research with a focus on the effects of estrogen and selective estrogen receptor modulators (SERMs). Preclinical studies and clinical trials of estrogen therapy have reported inconsistent results. However, almost all studies assessing SERM treatment have obtained more consistent and favorable effects in OA with a relatively safety and tolerability profiles. At present, some SERMs including raloxifene and bazedoxifene have been approved for the treatment of osteoporosis. In summary, estrogen-related agents may exert both a direct effect on subchondral bone and direct and/or indirect effects upon the surrounding tissues, including the articular cartilage, synovium, and muscle, to name a few. Estrogen and SERMs may be particularly favorable for postmenopausal patients with early-stage OA or osteoporotic OA, a phenotype defined by reduced bone mineral density related to high remodeling in subchondral bone. At present, no single drug exists that can prevent OA progression. Although estrogen-related drugs provide insight into the continued work in the field of OA drug administration, further research is required before SERMs can become therapeutic alternatives for OA treatment.

Aromatase expression in human chondrocytes: An induction due to culture

OBJECTIVES

Despite the high prevalence of osteoarthritis (OA) in postmenopausal women, a relationship between circulating estrogen levels and the development of OA has not been found. Therefore, the purpose of this study was to evaluate the expression and activity of aromatase, a key enzyme in local production of estrogens, in human OA cultured articular chondrocytes, and to determine the physiological relevance of this enzyme in cartilage.

METHODS

Human OA articular chondrocytes were isolated and cultured. Local production of estradiol was measured after incubation with 100 ng/ml testosterone for 8 and 24h. Furthermore, chondrocytes were culture for 2h, 48 h, 7 days or 15 days, or in alginate beads for 10 days. Aromatase, type II and X collagen, aggrecan, alkaline phosphatase, and Runx2 expression were evaluated in cartilage, freshly isolated chondrocytes and cultured chondrocytes.

RESULTS

Aromatase was expressed and active in cultured human chondrocytes. Human cartilage, freshly isolated chondrocytes, and chondrocytes cultured for 2h expressed an insignificant amount of aromatase; however, expression arose after 48 h of culture and remained increased thereafter. Aromatase expression was not related to estrogen deprivation and was inversely correlated with differentiation. Re-differentiation did not reduce its expression.

CONCLUSIONS

Aromatase presents an almost undetectable expression in human cartilage but is induced in cultured chondrocytes. Therefore, human cartilage might act as a mere target for estrogens rather than a producer, and researchers using cell expansion in culture for latter therapies should consider these changes in estrogen metabolism which may not be reverted after re-differentiation.

Hand osteoarthritis, menopause and menopausal hormone therapy

Hand osteoarthritis (OA) is one of the commonest musculoskeletal conditions, primarily affecting women over the age of 50, typically around the age of the menopause. Symptomatic disease can give rise to substantial pain, impairment of hand function and quality of life, leading to significant socioeconomic cost. There is currently no disease-modifying therapy, representing a huge unmet clinical need. The evidence for a relationship between hand OA and the menopause is summarised. Whether there is evidence for an effect of menopausal hormonal therapy on the incidence, prevalence or severity of symptomatic hand OA is critically reviewed, and gaps in our knowledge identified. Lastly, the potential mechanisms by which estrogen, or newer agents such as SERMs, might act to interfere with disease pathogenesis are overviewed. The need for specifically designed, controlled trials of agents in cohorts with symptomatic hand OA, refractory to standard symptomatic management is highlighted.

Experimental osteoarthritis models in mice

Osteoarthritis (OA) is a slowly progressing, degenerative disorder of synovial joints culminating in the irreversible destruction of articular cartilage and subchondral bone. It affects almost everyone over the age of 65 and influences life quality of affected individuals with enormous costs to the health care system. Current therapeutic strategies seek to ameliorate pain and increase mobility; however, to date none of them halts disease progression or regenerates damaged cartilage or bone. Thus, there is an ultimate need for the development of new, noninvasive treatments that could substitute joint replacement for late- or end-stage patients. Therefore, osteoarthritis animal models for mimicking of all OA features are important. Mice develop an OA pathology that is comparable to humans, rapidly develop OA due to the short lifetime and show reproducible OA symptoms. They provide a versatile and widely used animal model for analyzing molecular mechanisms of OA pathology. One major advantage over large animal models is the availability of knockout or transgenic mice strains to examine genetic predispositions/contributions to OA.In this chapter, we describe three widely used instability-inducing murine osteoarthritis models. The most common two methods for surgical induction are: (1) destabilization of the medial meniscus (DMM) and (2) anterior cruciate ligament transection (ACLT). In the DMM model, the medial meniscotibial ligament is transected while in the ACLT model the anterior cruciate ligament is destroyed. In the third, chemical induced instability method, intraarticular collagenase is injected into the knee joint. Intraarticular collagenase weakens articular ligaments which cause instability of the joint, and full-blown OA develops within 6 weeks. For morphological evaluation, we correspond mainly to the recommendations of OARSI for histological assessment of osteoarthritis in mouse. For statistical evaluation summed or mean scores of all four knee areas (medial tibial plateau (MTP), medial tibial condyle (MFC), lateral tibial plateau (LTP) or lateral femoral condyle (LFC)), medial and/or lateral regions are used.In future, not only large animal models like guinea pigs, sheep, goats, or horses will be important for a better understanding of osteoarthritis, but especially the mouse model with its rapid development of osteoarthritis and its numerous advantages by providing knockout or transgenic strains will become more and more relevant for drug development and determination of genetic predispositions of osteoarthritis pathology.

Estrogen alone and joint symptoms in the Women's Health Initiative randomized trial

OBJECTIVE

Although joint symptoms are commonly reported after menopause, observational studies examining exogenous estrogen's influence on joint symptoms provide mixed results. Against this background, estrogen-alone effects on joint symptoms were examined in post hoc analyses in the Women's Health Initiative randomized, placebo-controlled, clinical trial.

METHODS

A total of 10,739 postmenopausal women who have had a hysterectomy were randomized to receive daily oral conjugated equine estrogens (0.625 mg/d) or a matching placebo. The frequency and severity of joint pain and joint swelling were assessed by questionnaire in all participants at entry and on year 1, and in a 9.9% random subsample (n = 1,062) after years 3 and 6. Logistic regression models were used to compare the frequency and severity of symptoms by randomization group. Sensitivity analyses evaluated adherence influence on symptoms.

RESULTS

At baseline, joint pain and joint swelling were closely comparable in the randomization groups (about 77% with joint pain and 40% with joint swelling). After 1 year, joint pain frequency was significantly lower in the estrogen-alone group compared with the placebo group (76.3% vs 79.2%, P = 0.001), as was joint pain severity, and the difference in pain between randomization groups persisted through year 3. However, joint swelling frequency was higher in the estrogen-alone group (42.1% vs 39.7%, P = 0.02). Adherence-adjusted analyses strengthen estrogen's association with reduced joint pain but attenuate estrogen's association with increased joint swelling.

CONCLUSIONS

The current findings suggest that estrogen-alone use in postmenopausal women results in a modest but sustained reduction in the frequency of joint pain.

The associations between parity, other reproductive factors and cartilage in women aged 50-80 years

OBJECTIVE

Sex hormones and reproductive factors may be important for osteoarthritis (OA). The aim of this study was to describe the associations of parity, use of hormone replacement therapy (HRT) and oral contraceptives (OCs) with cartilage volume, cartilage defects and radiographic OA in a population-based sample of older women.

DESIGN

Cross-sectional study of 489 women aged 50-80 years. Parity, use of HRT and OC was assessed by questionnaire; knee cartilage volume and defects by magnetic resonance imaging and knee joint space narrowing (JSN) and osteophytes by X-ray.

RESULTS

Parity was associated with a deficit in total knee cartilage volume [adjusted β=-0.69 ml, 95% confidence interval (CI) -1.34, -0.04]. Increasing parity was associated with decreasing cartilage volume in both the tibial compartment and total knee (both P trend <0.05). Parity was also associated with greater cartilage defects in the patella compartment [adjusted odds ratio (OR)=2.87, 95% CI=1.39, 5.93] but not other sites. There was a consistent but non-significant increase in knee JSN (OR=2.78, 95% CI=0.75, 10.31) and osteophytes (OR=1.69, 95% CI=0.59, 4.82) for parous women. Use of HRT and/or OC was not associated with cartilage volume, cartilage defects or radiographic change.

CONCLUSIONS

Parity (but not use of HRT or OC) is independently associated with lower cartilage volume primarily in the tibial compartment and higher cartilage defects in the patella compartment in this population-based sample of older women.

Weight gain and the risk of total hip replacement a population-based prospective cohort study of 265,725 individuals

OBJECTIVE

To study the association between change in the body mass index (BMI) at different ages and the risk of a later total hip replacement (THR) due to primary osteoarthritis (OA).

DESIGN

A total of 265,725 individuals who had two repeated measurements of weight and height were included from national health screenings. These individuals were followed prospectively. The data were matched with the Norwegian Arthroplasty Register and 4,442 of these individuals were identified as having received a THR for primary OA. Cox proportional hazard regression was used to calculate sex-specific relative risks for having a THR according to age at screening and BMI change.

RESULTS

Men and women aged 20 years or younger at the first screening in the quartile with the greatest BMI change per year had more than twice the risk of later having a THR compared with those in the quartile with the smallest BMI change per year. For men older than 30 years at the first screening, there was no relationship between BMI gain, or weight gain, and later risk of THR. For older women, BMI gain was associated with risk of THR, but to a lesser degree than in younger women.

CONCLUSION

There was a clear relationship between change in BMI and the risk of later THR in young men and women, whereas the association was absent in older men and weaker in older women. It is important to focus on weight control to prevent future OA, and the preventive strategy should be focused on the young population.

Osteoarthritis subpopulations and implications for clinical trial design

Treatment guidelines for osteoarthritis have stressed the need for research on clinical predictors of response to different treatments. However, identifying such clinical predictors of response is less easy than it seems, and there is not a given classification of osteoarthritis subpopulations. This review article highlights the key methodical issues when analyzing and designing clinical studies to detect important subgroups with respect to treatment effect. In addition, we discuss the main osteoarthritis subpopulations and give examples of how specific treatment effects in these subpopulations have been assessed.

Inflammatory osteoarthritis which was precipitated by Arimidex and resolved with tamoxifen

We report the case of a 51-year-old woman who presented with an inflammatory flare of osteoarthritis of the small joints of her hands occurring in a temporal relationship with the commencement of Arimidex, prescribed to reduce systemic oestrogen levels to treat breast cancer. Following the cessation of Arimidex and the initiation of tamoxifen, a specific oestrogen receptor antagonist, this flare resolved. It has long been observed that during the menopause, as oestrogen levels decline, many women develop osteoarthritis or experience progression of the disease. However, this theory of oestrogen-dependent osteoarthritis has not been consistently demonstrated in animal models. As far as the authors are aware, this is the first case in which systemic oestrogen reduction has resulted in a severe osteoarthritis flare but targeted oestrogen receptor blockade led to a resolution of symptoms. These findings may inform the pathophysiological process underlying oestrogen-dependent osteoarthritis, although further series are needed.

Hypertrophic differentiation of chondrocytes in osteoarthritis: the developmental aspect of degenerative joint disorders

Osteoarthritis is characterized by a progressive degradation of articular cartilage leading to loss of joint function. The molecular mechanisms regulating pathogenesis and progression of osteoarthritis are poorly understood. Remarkably, some characteristics of this joint disease resemble chondrocyte differentiation processes during skeletal development by endochondral ossification. In healthy articular cartilage, chondrocytes resist proliferation and terminal differentiation. By contrast, chondrocytes in diseased cartilage progressively proliferate and develop hypertrophy. Moreover, vascularization and focal calcification of joint cartilage are initiated. Signaling molecules that regulate chondrocyte activities in both growth cartilage and permanent articular cartilage during osteoarthritis are thus interesting targets for disease-modifying osteoarthritis therapies.

New developments in osteoarthritis. Sex differences in magnetic resonance imaging-based biomarkers and in those of joint metabolism

Sex differences in the prevalence, incidence, and severity of osteoarthritis (OA) have long been known. Some differences in the evaluation of this issue across studies may be related to differences in study design, sampling, study size, study populations, targeted joint sites, and definitions of OA. This report highlights recent studies of sex differences in individual joint components imaged by magnetic resonance imaging and in systemic biomarkers of joint metabolism. Particularly important are those studies that examine this issue in young unaffected adults and children before the development of disease. Despite some variation across studies, women appear for the most part to have a thinner and more reduced volume of cartilage in the knee than men, and this may occur from early childhood. It is not clear whether women have a more accelerated rate of cartilage volume loss than men. Few data exist on sex differences in systemic biomarkers of joint metabolism. In these studies, it is critically important to characterize the total body burden of OA and the presence of comorbid conditions likely to influence a given biomarker. Lastly, future research should dovetail studies of sex differences in imaging and biochemical biomarkers with genetics to maximize insight into the mechanisms behind observed sex differences.

Osteoarthritis in Women: Effects of Estrogen, Obesity and Physical Activity

Arthritis is the leading cause of physical disability in the USA and osteoarthritis (OA), the most common form, affects nearly 27 million people. Women have a higher prevalence of OA than men, but the underlying causes for the increased susceptibility of women to OA are not fully understood. This review discusses the associations of sex hormones, obesity and physical activity with the incidence and progression of OA in women. Although many studies have explored the relationships of estrogen and reproductive history with the risk of OA or joint replacement, there is no consensus on the role of these factors. Obesity clearly increases risk for OA, but whether obesity affects women and men differently is uncertain. Moderate levels of physical activity do not appear to increase the incidence or progression of OA and may even have a weak protective effect. Future investigations should focus on sex-specific mechanisms for the development of OA and determine whether there are modifiable factors (e.g., estrogen, obesity, physical activity) that can be targeted through prevention and treatment strategies to mitigate the increased incidence and prevalence of OA in women.

Common variations in estrogen-related genes are associated with severe large-joint osteoarthritis: a multicenter genetic and functional study

OBJECTIVE

Several lines of evidence suggest that estrogens influence the development of osteoarthritis (OA). The aim of this study was to explore the association of two common polymorphisms within the aromatase (CYP19A1) and estrogen receptor (ER) alpha (ESR1) genes with severe OA of the lower limbs.

METHODS

The rs1062033 (CYP19A1) and rs2234693 (ESR1) single nucleotide polymorphisms were genotyped in 5528 individuals (3147 patients with severe hip or knee OA, and 2381 controls) from four centres in Spain and the United Kingdom. Gene expression was measured in femoral bone samples from a group of patients.

RESULTS

In the global analysis, both polymorphisms were associated with OA, but there was a significant sex interaction. The GG genotype at rs1062033 was associated with an increased risk of knee OA in women [odds ratio (OR) 1.23; P=0.04]. The CC genotype at rs2234693 tended to be associated with reduced OA risk in women (OR 0.76, P=0.028, for knee OA; OR=0.84, P=0.076 for hip OA), but with increased risk of hip OA in men (OR 1.28; P=0.029). Women with unfavourable genotypes at both loci had an OR of 1.61 for knee OA (P=0.006). The rs1062033 genotype associated with higher OA risk was also associated with reduced expression of the aromatase gene in bone.

CONCLUSIONS

Common genetic variations of the aromatase and ER genes are associated with the risk of severe OA of the large joints of the lower limb in a sex-specific manner. These results are consistent with the hypothesis that estrogen activity may influence the development of large-joint OA.

Osteoarthritis associated with estrogen deficiency

Osteoarthritis (OA) affects all articular tissues and finally leads to joint failure. Although articular tissues have long been considered unresponsive to estrogens or their deficiency, there is now increasing evidence that estrogens influence the activity of joint tissues through complex molecular pathways that act at multiple levels. Indeed, we are only just beginning to understand the effects of estrogen deficiency on articular tissues during OA development and progression, as well as on the association between OA and osteoporosis. Estrogen replacement therapy and current selective estrogen receptor modulators have mixed effectiveness in preserving and/or restoring joint tissue in OA. Thus, a better understanding of how estrogen acts on joints and other tissues in OA will aid the development of specific and safe estrogen ligands as novel therapeutic agents targeting the OA joint as a whole organ.

No clear association between female hormonal aspects and osteoarthritis of the hand, hip and knee: a systematic review

OBJECTIVE

Incidence of OA rises steeply in women of age >50 years; the climacteric period for women. The simultaneous occurrence of these events suggests an association between OA and changes in female hormonal aspects. This systematic review studies the assumed association between OA and aspects concerning the fertile period (duration, endogenous hormones, age at menarche/menopause) and the menopause [menopausal status, years since menopause (YSM) and surgical menopause].

METHODS

Medline and EMBASE were searched for articles assessing associations between hand/hip/knee OA and female hormonal aspects. Methodological quality was assessed systematically, and results were summarized in a best-evidence synthesis.

RESULTS

Sixteen studies were included in the present study. For most hormonal aspects no association was found. Conflicting evidence was found for an association of age at menarche with Herberden's nodes (HNs) and hand ROA, YSM with knee ROA and ovariectomy with hip OA. An increased risk was seen for low estradiol serum levels in the early follicular phase with incident knee ROA, age at menarche being < or =11 years old with total hip replacement, being post-menopausal and YSM with the presence of HN. A protective effect was seen for age at menopause being > or =52 years with total knee replacement. Evidence level was limited for all.

CONCLUSIONS

The assumed relationship between the female hormonal aspects and OA was not clearly observed in this review. The relationship is perhaps too complex, or other aspects, yet to be determined, play a role in the increased incidence in women aged >50 years.