Oral contraceptives and rheumatoid arthritis: results from a primary care-based incident case-control study

Health benefits of combined oral contraceptives - a narrative review

PURPOSE

This review presents an update of the non-contraceptive health benefits of the combined oral contraceptive pill.

METHODS

We conducted a literature search for (review) articles that discussed the health benefits of combined oral contraceptives (COCs), in the period from 1980 to 2023.

RESULTS

We identified 21 subjective and/or objective health benefits of COCs related to (i) the reproductive tract, (ii) non-gynaecological benign disorders and (iii) malignancies. Reproductive tract benefits are related to menstrual bleeding(including anaemia and toxic shock syndrome), dysmenorrhoea, migraine, premenstrual syndrome (PMS), ovarian cysts, Polycystic Ovary Syndrome (PCOS), androgen related symptoms, ectopic pregnancy, hypoestrogenism, endometriosis and adenomyosis, uterine fibroids and pelvic inflammatory disease (PID). Non-gynaecological benefits are related to benign breast disease, osteoporosis, rheumatoid arthritis, multiple sclerosis, asthma and porphyria. Health benefits of COCs related to cancer are lower risks of endometrial cancer, ovarian cancer and colorectal cancer.

CONCLUSIONS

The use of combined oral contraceptives is accompanied with a range of health benefits, to be balanced against its side-effects and risks. Several health benefits of COCs are a reason for non-contraceptive COC prescription.

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.

Association of pregnancy complications/risk factors with the development of future long-term health conditions in women: overarching protocol for umbrella reviews

INTRODUCTION

With good medical care, most pregnancy complications like pre-eclampsia, gestational diabetes, etc resolve after childbirth. However, pregnancy complications are known to be associated with an increased risk of new long-term health conditions for women later in life, such as cardiovascular disease. These umbrella reviews aim to summarise systematic reviews evaluating the association between pregnancy complications and five groups of long-term health conditions: autoimmune conditions, cancers, functional disorders, mental health conditions and metabolic health conditions (diabetes and hypertension).

METHODS AND ANALYSIS

We will conduct searches in Medline, Embase and the Cochrane database of systematic reviews without any language restrictions. We will include systematic reviews with or without meta-analyses that studied the association between pregnancy complications and the future risk of the five groups of long-term health conditions in women. Pregnancy complications were identified from existing core outcome sets for pregnancy and after consultation with experts. Two reviewers will independently screen the articles. Data will be synthesised with both narrative and quantitative methods. Where a meta-analysis has been carried out, we will report the combined effect size from individual studies. For binary data, pooled ORs with 95% CIs will be presented. For continuous data, we will use the mean difference with 95% CIs. The findings will be presented in forest plots to assess heterogeneity. The methodological quality of the studies will be evaluated with the AMSTAR 2 tool or the Cochrane risk of bias tool. The corrected covered area method will be used to assess the impact of overlap in reviews. The findings will be used to inform the design of prediction models, which will predict the risk of women developing these five group of health conditions following a pregnancy complication.

ETHICS AND DISSEMINATION

No ethical approvals required. Findings will be disseminated through publications in peer-reviewed journals and conference presentations.

Hormonal and Reproductive Factors in Relation to Cardiovascular Events in Women with Early Rheumatoid Arthritis

Hormonal and reproductive factors affect the risk for cardiovascular events (CVE) in the general population. Although the risk of CVE is increased in rheumatoid arthritis (RA), the knowledge about the impact of hormonal factors for CVE in RA is sparse. Female postmenopausal patients ≤80 years with early RA were consecutively included in this observational study (n = 803) between 1 January 1996 until 31 December 2017. Questionnaires regarding hormonal factors were distributed from the index date. Data regarding CVE were obtained from the Swedish National Health Register and Cause of Death Register. Associations between CVE and hormonal factors were analyzed using Cox proportional hazard regression. Of the postmenopausal women, 64 women had a CVE after RA onset. The time period from menopause to RA onset was significantly longer for CVE cases with higher proportion of postmenopausal women. In Cox proportional hazard regression models, years from last childbirth and multiparity were associated with higher CVE risk. Adjustments for traditional risk factors did not affect the results except for hypertension. RA onset after menopause and a longer duration from menopause until onset increased the CVE risk. Multiparity was associated with higher CVE risk whilst oral contraceptives decreased the risk. These results can contribute to identification of high-risk patients for CVE beyond traditional risk factors.

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

Rheumatoid arthritis (RA) is the most common inflammatory rheumatic disease and has a female predominance of around 3:1. The relationship between sex hormones and RA has been of great interest to researchers ever since Philip Hench's observations in the 1930's regarding spontaneous disease amelioration in pregnancy. Extensive basic scientific work has demonstrated the immunomodulatory actions of sex hormones but this therapeutic potential has not to date resulted in successful clinical trials in RA. Epidemiological data regarding both endogenous and exogenous hormonal factors are inconsistent, but declining estrogen and/or progesterone levels in the menopause and post-partum appear to increase the risk and severity of RA. This review assimilates basic scientific, epidemiological and clinical trial data to provide an overview of the current understanding of the relationship between sex hormones and RA, focusing on estrogen, progesterone and androgens.

Combined oral contraceptive use in rheumatoid arthritis for the purpose of pregnancy prevention and additional benefits: A narrative review

Combined oral contraceptives are a common method of contraception and many females prefer them regardless of their medical history. The use in patients with rheumatoid and autoimmune disorders has not been extensively studied with previous reviews focusing on the safety component. This review seeks to address the effectiveness and benefits of utilizing combined oral contraceptives in females with rheumatoid arthritis (RA). Current literature regarding combined oral contraceptives was surveyed for its use in RA and two PubMed searches were conducted, yielding 202 and 142 results, respectively. Results were screened and analyzed for relevance to this review topic. Eighteen results, consisting of clinical trials, observational studies, patient cases, and meta-analyses were used in this narrative review. Historically, it was thought that females with an autoimmune disorder such as RA need to be on contraception due to the teratogenicity potential with disease-modifying therapy but no evidence exists about which type of contraception is the most effective and least interacting. Current evidence available shows no preference for types of contraception in this population, but it has been demonstrated that combination oral contraceptives may provide contraceptive benefits and have a potential for other benefits such as less disability and the prevention of disease progression. Although current evidence provides reasoning to believe combination oral contraceptives are safe and efficacious in patients with RA and may even offer additional benefits, further studies and clinical trials are needed to completely understand the role combination oral contraceptives play in this patient population.

Female hormonal exposures and risk of rheumatoid arthritis in the French E3N-EPIC cohort study

OBJECTIVE

To assess the relationships between female hormonal exposures and risk of RA in a prospective cohort of French women.

METHODS

E3N (Etude Epidémiologique auprès des femmes de la Mutuelle générale de l'Education Nationale) is an on-going French prospective cohort that included 98 995 women aged 40-65 years in 1990. Every 2-3 years, women completed mailed questionnaires on their lifestyles, reproductive factors and health conditions. Cox proportional hazards regression models were used to determine factors associated with risk of incident RA, with age as the time scale, adjusted for known risk factors of RA, and considering endogenous and exogenous hormonal factors. Hazard ratios (HRs) and 95% CIs were estimated. Effect modification by smoking history was investigated.

RESULTS

A total of 698 incident cases of RA were ascertained among 78 452 women. In multivariable-adjusted Cox regression models, risk of RA was increased with early age at first pregnancy (<22 vs ≥27 years; HR = 1.34; 95% CI 1.0, 1.7) and menopause (≤45 vs ≥53 years; HR = 1.40; 95% CI 1.0, 1.9). For early menopause, the association was of similar magnitude in ever and never smokers, although the association was statistically significant only in ever smokers (HR = 1.54; 95% CI 1.0, 2.3). We found a decreased risk in nulliparous women never exposed to smoking (HR = 0.44; 95% CI 0.2, 0.8). Risk of RA was inversely associated with exposure to progestogen only in perimenopause (>24 vs 0 months; multi-adjusted HR = 0.77; 95% CI 0.6, 0.9).

CONCLUSIONS

These results suggest an effect of both endogenous and exogenous hormonal exposures on RA risk and phenotype that deserves further investigation.

Estrogen induces St6gal1 expression and increases IgG sialylation in mice and patients with rheumatoid arthritis: a potential explanation for the increased risk of rheumatoid arthritis in postmenopausal women

BACKGROUND

Rheumatoid arthritis (RA) preferentially affects women, with the peak incidence coinciding with estrogen decrease in menopause. Estrogen (E2) may therefore have intrinsic immune-regulatory properties that vanish with menopause. Fc sialylation is a crucial factor determining the inflammatory effector function of antibodies. We therefore analyzed whether E2 affects immunoglobulin G (IgG) sialylation.

METHODS

Postmenopausal (ovariectomized) mice were immunized with ovalbumin and treated with E2 or vehicle. Total and ovalbumin-specific IgG concentrations, sialylation, and Fcγ receptor expression were analyzed. Postmenopausal women with RA receiving hormone replacement therapy, including E2, or no treatment were analyzed for IgG sialylation. Furthermore, effects of E2 on the expression of the sialylation enzyme β-galactoside α2,6-sialyltransferase 1 (St6Gal1) were studied in mouse and human antibody-producing cells.

RESULTS

E2 treatment significantly increased Fc sialylation of total and ovalbumin-specific IgG in postmenopausal mice. Furthermore, E2 led to increased expression of inhibitory Fcγ receptor IIb on bone marrow leukocytes. Treatment with E2 also increased St6Gal1 expression in mouse and human antibody-producing cells, providing a mechanistic explanation for the increase in IgG-Fc sialylation. In postmenopausal women with RA, treatment with E2 significantly increased the Fc sialylation of IgG.

CONCLUSIONS

E2 induces anti-inflammatory effector functions in IgG by inducing St6Gal1 expression in antibody-producing cells and by increasing Fc sialylation. These observations provide a mechanistic explanation for the increased risk of RA in conditions with low estrogen levels such as menopause.

Rheumatoid arthritis is getting less frequent-results of a nationwide population-based cohort study

Objectives

The objectives of this study were to examine changes in the incidence and prevalence of RA between 1990 and 2014 and to explore if there is any geographic variation in the incidence and prevalence of RA in the UK.

Methods

This was a primary care-based prospective cohort study. People contributing acceptable data to Clinical Practice Research Datalink between 1 January 1990 and 31 December 2014 were included. Read codes were used to identify RA cases ⩾18 years of age. The prevalence and incidence rates for each year were standardized to the 2014 population and the regional incidence and prevalence of RA for the year 2014 were standardized to the overall population.

Results

The incidence and prevalence of RA was 3.81/10 000 person-years and 0.67%, respectively, in 2014. The annual incidence of RA decreased by 1.6% (95% CI 0.8, 2.5) between 1990 and 2014, with significant joinpoints at 1994 and 2002. The prevalence of RA increased by 3.7%/year (95% CI 3.2, 4.1) from 1990 to 2005 and decreased by 1.1%/year (95% CI 2.0, 0.2) between 2005 and 2014. There were significant differences in the occurrence of RA throughout different regions of the UK, with the highest incidence in East Midlands, Yorkshire and Humber and the highest prevalence in North East, Yorkshire and Humber.

Conclusion

The incidence of RA is decreasing, with a reduction in prevalence in recent years. There is significant geographic variation in the occurrence of RA in the UK. Further research is required to identify the reasons underlying this phenomenon so that public health interventions can be designed to further reduce the incidence of RA.

Oral contraceptives, breastfeeding and the risk of developing rheumatoid arthritis: results from the Swedish EIRA study

OBJECTIVES

To study whether oral contraceptive (OC) use or breastfeeding (BF) influence the risk of rheumatoid arthritis (RA), stratifying the cases by presence/absence of anticitrullinated protein antibodies (ACPA), and whether these factors interact with known risk factors in the development of ACPA-positive RA.

METHODS

Women aged ≥18 years, participants in the population-based case-control Swedish Epidemiological Investigation of RA study (2641 cases/4251 controls), completed an extensive questionnaire regarding OC, BF and potential confounders. We calculated ORs, with 95% CIs, adjusted for age, residential area, smoking and alcohol consumption. Attributable proportion due to interaction (AP) was estimated to evaluate presence of interaction.

RESULTS

Compared with never users, ever and past OC users had a decreased risk of ACPA-positive RA (OR=0.84 (95% CI 0.74 to 0.96); OR=0.83 (95% CI 0.73 to 0.95), respectively). No significant associations were found for ACPA-negative RA. Long duration of OC use (>7 years vs never use) decreased the risk of both ACPA-positive (p=0.0037) and ACPA-negative RA (p=0.0356).A history of long BF decreased the risk only of ACPA-positive RA in a dose-dependent manner (p=0.0086), but this trend did not remain after adjustments. A significant interaction was observed between the lack of OC use and smoking (AP=0.28 (95% CI 0.14-0.42)) on the risk of ACPA-positive RA. No interactions were found for BF.

CONCLUSIONS

OC decreased the risk of RA, especially ACPA-positive RA, where an interaction with smoking was observed. A long duration of OC use decreased the risk of both disease subsets. We could not confirm an association between BF and a decreased risk of either ACPA-positive or ACPA-negative RA.

Postmenopausal hormone therapy and the risk of rheumatoid arthritis: results from the Swedish EIRA population-based case-control study

To study the association between postmenopausal hormone therapy (PMH) use and the risk of rheumatoid arthritis (RA) stratifying the cases by the presence/absence of antibodies against citrullinated peptides (ACPA). A subset of the Epidemiological Investigation of RA (EIRA), a population-based case-control study, comprising postmenopausal women aged 50–70 living in Sweden, between 2006 and 2011 was analysed (523 cases and 1057 controls). All participants answered an extensive questionnaire, including questions regarding PMH use and potential confounders (education, smoking, BMI, oral contraceptives, reproductive factors). We calculated odds ratios (OR) of developing ACPA-positive/-negative RA, with 95 % confidence intervals (CI) and adjusted for age, residential area and smoking. Current users of PMH had a decreased risk of ACPA-positive RA compared with never users (OR 0.6, 95 % CI 0.3–0.9). The decreased risk was observed mainly in the age-group 50–59 years (OR 0.3, 95 % CI 0.1–0.8) but not in the age-group 60–70 years (OR 0.8, 95 % CI 0.4–1.4). Among current users of a combined therapy (estrogen plus progestogens) an OR of 0.3 (95 % CI 0.1–0.7) of ACPA-positive RA was observed, while no significant association was found among women who used estrogen only (OR 0.8, 95 % CI 0.5–1.6). No association between PMH use and ACPA-negative RA was found. PMH use might reduce the risk of ACPA-positive RA in post-menopausal women over 50 years of age, but not of ACPA-negative RA. The negative influence of this treatment on the risk of other chronic conditions cannot be overlooked.

Meta-analysis of oral contraceptives and rheumatoid arthritis risk in women

Background and objectives

Epidemiological investigations of the relationship between oral contraceptives and rheumatoid arthritis (RA) risk have reported controversial results. Therefore, a meta-analysis of case-control or cohort studies was performed to evaluate the role of oral contraceptives in relation to risk of developing RA.

Methods

Eligible studies were identified from databases PubMed and EMBASE by searching and reviewing references. Random effect models were utilized to summarize the relative risk (RR) estimates with 95% confidence intervals (CIs).

Results

A total of 12 case-control studies and five cohort studies were eligible for our analysis. No statistically significant association was observed between oral contraceptives and RA risk (RR=0.88, 95% CI=0.75–1.03). In the subgroup of geographic area, a decreased risk of borderline significance was observed for oral contraceptive users in European studies (RR=0.79, 95% CI=0.62–1.01), but this association did not emerge in the North American studies group (RR=0.99, 95% CI=0.81–1.21). No evidence for publication bias was detected (P for Egger’s test =0.231).

Conclusion

Our results of meta-analysis do not support the hypothesis of a protective effect of oral contraceptives on the risk for RA in women.

Using lifestyle factors to identify individuals at higher risk of inflammatory polyarthritis (results from the European Prospective Investigation of Cancer-Norfolk and the Norfolk Arthritis Register--the EPIC-2-NOAR Study)

Objectives

To investigate the association of lifestyle factors with risk of inflammatory polyarthritis (IP) and rheumatoid arthritis (RA).

Methods

The European Prospective Investigation of Cancer, Norfolk, UK (EPIC-Norfolk) gathered lifestyle data from participants aged 40–79 years from 1993 to 1997. Individuals who subsequently developed IP were identified by linkage with the Norfolk Arthritis Register. A Cox proportional hazard model was developed, and a score assigned to each risk factor to calculate the odds of developing IP.

Results

25 455 EPIC participants were followed for a median (IQR) of 14.2 (12.9, 15.3) years; 184 developed incident IP (138 cumulatively fulfilled criteria for RA; 107 were seropositive). Pack-years of smoking were associated with increased risk of IP and RA in men (HR 1.21 (95% CI 1.08 to 1.37) per 10-pack-years) and seropositive IP (HR 1.24 (95% CI 1.10 to 1.41)) for all. Diabetes mellitus was associated with increased risk of IP (HR 2.54 (95% CI 1.26 to 5.09)), while alcohol (HR 0.86 (95% CI 0.74 to 0.99) per unit/day) and higher social class (HR 0.36 (95% CI 0.15 to 0.89) for professionals vs manual workers) were associated with reduced risk. Body mass index was associated with seronegative IP (HR 2.75 (95% CI 1.39 to 5.46) for obese vs normal-weight participants). In women, parity (HR 2.81 (95% CI 1.37 to 5.76) for ≥2 vs no children) was associated with increased risk, and breast feeding (HR 0.66 (95% CI 0.46 to 0.94) for every 52 weeks of breast feeding) was inversely associated with risk. Risk factors from the model were used to generate a ‘risk score’. A total of 1159 (8.4%) women had scores reflecting a >3-fold increased risk of IP over those with a score of 0.

Conclusions

Several easily ascertained clinical and lifestyle factors can be used to stratify populations for risk of IP.

What Have We Learned about the Pathogenesis of Rheumatoid Arthritis from TNF-Targeted Therapy?

Studies of cytokine regulation in rheumatoid arthritis led to the development of TNFα inhibitors which are now used for a number of indications, including rheumatoid arthritis, inflammatory bowel disease, psoriasis, psoriatic arthritis, and ankylosing spondylitis. The widespread use of biologics in the clinic offers unique opportunities for probing disease pathogenesis and this paper provides an overview of rheumatoid arthritis, with a particular emphasis on the impact of anti-TNFα therapy on pathogenetic mechanisms. An overview is also provided on the most commonly used animal models that mimic RA, including adjuvant-induced arthritis, collagen-induced arthritis, TNFα-transgenic mice, and the K/BxN and SKG models. These models have led to significant discoveries relating to the importance of pro-inflammatory cytokines in the pathogenesis of rheumatoid arthritis, resulting from disregulation of the normally finely tuned balance of pro- and anti-inflammatory cytokine signalling. In addition, experimental evidence is discussed suggesting how genetic and environmental factors can contribute to disease susceptibility. The role of effector and regulatory T cells is discussed in the light of the relatively disappointing therapeutic effects of T cell modifying agents such as anti-CD4 antibody and cyclosporin. It is concluded that comprehensive analyses of mechanisms of action of biologics and other drugs entering the clinic will be essential to optimise therapy, with the ultimate aim of providing a cure.

Early menopause and severity of rheumatoid arthritis in women older than 45 years

Introduction

We aimed to investigate whether recognized hormonal predictors of rheumatoid arthritis (RA) also influence the severity of RA.

Methods

One hundred thirty-four incident RA cases identified by four different local and national registers, who had participated in a community-based health survey between 1991 and 1996, were included. By a retrospective structured review of the medical records, information on the use of disease-modifying antirheumatic drugs (DMARDs), erosions on radiographs, rheumatoid factor (RF) status, and disability measured by using the health assessment questionnaire (HAQ) were collected. The variables were added to the SPSS TwoStep Cluster Analysis to reveal natural groupings of RA severity. Known hormonal predictors analyzed were breastfeeding history, history of oral contraceptive (OC) use, and menopausal age.

Results

The mean age at RA diagnosis was 63.4 years; 72% were RF positive, and 28% had received biological treatment. Three clusters were identified, one with severe RA, one with mild/moderate RF-positive RA, and one with mild/moderate RF-negative RA. A significant difference (P = 0.005) was found in the distribution of clusters between patients with a history of early menopause compared with those with menopause after 45 years, with a higher proportion with mild/moderate RF-negative RA in the early-menopause subset. No major difference in severity of the disease was noted depending on OC use or history of breastfeeding.

Conclusions

Early menopause was associated with a milder form of RA. Hormonal changes may influence pathways that are distinct from those leading to severe, progressive disease.

Environmental and gene-environment interactions and risk of rheumatoid arthritis

Multiple environmental factors including hormones, dietary factors, infections, and exposure to tobacco smoke, as well as gene-environment interactions, have been associated with increased risk for rheumatoid arthritis (RA). The growing understanding of the prolonged period before the first onset of symptoms of RA suggests that these environmental and genetic factors are likely acting to drive the development of RA-related autoimmunity long before the appearance of the first joint symptoms and clinical findings that are characteristic of RA. This article reviews these factors and interactions, especially those that have been investigated in a prospective fashion before the symptomatic onset of RA.

Tobacco and other environmental risk factors in rheumatoid arthritis

Many environmental factors have been associated with an increased risk of developing Rheumatoid Arthritis (RA), but so far smoking is the only environmental risk factor that has been extensively studied and widely accepted. Smoking is associated with an increased risk of developing seropositive RA (RF and/or ACPA). Recent studies show that tobacco smoking can influence disease phenotype, with the development of more aggressive disease and greater joint damage; but other studies show contradictory results. Recent data suggests that response to antirheumatic therapy in RA is worse in smokers. In this article we review different environmental factors that have been associated with an increased risk of developing RA, with a special interest in tobacco smoking.

[Chronic inflammatory arthritis and pregnancy]

BACKGROUND

Chronic inflammatory arthritis often appears first in women of fertile age. Their pregnancies are considered to be of low risk compared with pregnancies in women with systemic inflammatory connective tissue disease.

METHOD

The article is based on literature searches in PubMed for studies of the pregnancy outcomes of women with chronic inflammatory arthritis. Studies without a reference group or studies based on analyses of mixed populations of inflammatory arthritis and connective tissue disease patients were excluded.

RESULTS

Recurrent findings in the published literature were: low mean birth weight, a higher proportion of children with a birth weight of less than 2500 grams, children born small for gestational age, preterm births and a higher proportion of Caesarean sections. A high level of disease activity is associated with the risk of low birth weight and preterm birth. However, serious complications are not frequently reported. Glucocorticosteroids and disease-modifying medicines such as sulphasalazine and hydroxychloroquine may be used during pregnancy. Non-steroidal anti-inflammatory drugs such as ibuprofen and naproxen may be used until gestational week 32. Methotrexate is contraindicated and must be terminated three months before conception. The TNF inhibitors adalimumab, etanercept and infliximab may be used until conception.

INTERPRETATION

Pregnancy is seldom absolutely contraindicated for women with inflammatory arthritis. Pregnancy should be planned carefully and preferably be confined to periods with a low level of disease activity. First pregnancies require special attention. Interdisciplinary collaboration between rheumatologists and gynaecologists is recommended for monitoring patients with active arthritis.

Modifiable risk factors for RA: prevention, better than cure?

Objective. To perform a meta-synthesis of the evidence for modifiable lifestyle risk factors for inflammatory polyarthritis (IP) and RA.

Methods. We performed a MEDLINE literature search. Case–control and cohort studies and systematic reviews published from 1948 through February 2011 and studying modifiable risk factors for RA were retrieved. The main outcome measure was diagnosis of RA according to the standard criteria.

Results. Smoking contributes up to 25% of the population burden of RA. The risk is dose related, stronger in males and especially strong for anti-citrullinated peptide antibody positive (ACPA⁺) RA through an interaction with the shared epitope. After smoking cessation, there is, however, a latency of up to 20 years to return to baseline risk. Other associations are less definitive; however, prospective studies suggest that dietary antioxidants and breastfeeding may be protective and that high coffee consumption may increase RA risk. An inverse association with alcohol intake (especially in smokers) and with education/social class (especially seropositive RA) and an increased risk with obesity (seronegative RA) is also noted.

Conclusion. There is a need for further large-scale prospective studies with a consistent definition of RA phenotype (undifferentiated IP through to ACPA⁺/RF⁺ disease). This will ultimately afford the opportunity to evaluate preventative population strategies for RA akin to the well-established programmes for cardiovascular disease and cancer, targeting common risk factors.

The relationship between oral contraceptive use and functional outcome in women with recent-onset inflammatory polyarthritis: results from the Norfolk Arthritis Register

OBJECTIVE

Use of oral contraceptives (OCs) may prevent the development of rheumatoid arthritis, but the influence of OC use on disease outcome is unresolved. The purpose of this study was to examine functional outcome and OC use in women with inflammatory polyarthritis (IP).

METHODS

The Norfolk Arthritis Register (NOAR) is an inception cohort of patients with recent-onset IP. We studied patient-reported history of OC use in 663 women who were born after 1945 and who had not used OCs during followup. OC use during followup was additionally investigated in 265 women who were <50 years old and had not undergone menopause or hysterectomy during followup. All patients were recruited to the NOAR between 1990 and 2004. Functional ability was assessed using the Health Assessment Questionnaire (HAQ), with adjustment for age at symptom onset.

RESULTS

The median followup was 4.9 years. In the investigation analyzing OC use before symptom onset, patients who had used OCs before symptom onset had lower HAQ scores throughout followup than patients who had not taken OCs before symptom onset (difference in score at 5-year followup -0.35; 95% confidence interval [95% CI] -0.51, -0.19). Patients who were taking OCs at baseline had lower HAQ scores over time than women who were not taking OCs at baseline but had previously done so (mean difference -0.21; 95% CI -0.40, -0.02). In the investigation analyzing OC use during followup, OC use during followup was associated with lower HAQ scores over time than no OC use during followup (mean difference -0.06; 95% CI -0.16, 0.03); however, this was only significant for women with moderate or severe functional disability at the previous assessment (mean difference -0.23; 95% CI -0.40, -0.07). Further adjustment for potential confounders and exclusion of hormone replacement therapy users had little impact.

CONCLUSION

OC use is generally associated with a beneficial functional outcome in IP, and use before and at symptom onset appeared to have the most consistent benefit.

Estrogens in rheumatoid arthritis; the immune system and bone

Rheumatoid arthritis (RA) is an autoimmune disease that is more common in women than in men. The peak incidence in females coincides with menopause when the ovarian production of sex hormones drops markedly. RA is characterized by skeletal manifestations where production of pro-inflammatory mediators, connected to the inflammation in the joint, leads to bone loss. Animal studies have revealed distinct beneficial effects of estrogens on arthritis, and a positive effect of hormone replacement therapy has been reported in women with postmenopausal RA. This review will focus on the influence of female sex hormones in the pathogenesis and progression of RA.

Role of endogenous and exogenous female sex hormones in arthritis and osteoporosis development in B10.Q-ncf1*/* mice with collagen-induced chronic arthritis

Background

Collagen-induced arthritis (CIA) is an often-used murine model for human rheumatoid arthritis (RA). Earlier studies have shown potent anti-arthritic effects with the female sex hormone estradiol and the selective estrogen receptor modulator (SERM) raloxifene in CIA in DBA/1-mice. B10.Q-ncf1^*/*mice are B10.Q mice with a mutated Ncf1 gene. In B10.Q-ncf1^*/*mice, CIA develops as a chronic relapsing disease, which more accurately mimics human RA. We investigated the role of endogenous and exogenous sex steroids and raloxifene in the course of this model of chronic arthritis. We also examined whether treatment would prevent the development of inflammation-triggered generalized osteoporosis.

Methods

Female B10.Q-ncf1^*/*mice were sham-operated or ovariectomized, and CIA was induced. 22 days later, when 30% of the mice had developed arthritis, treatment with raloxifene, estradiol or vehicle was started, and the clinical disease was evaluated continuously. Treatment was continued until day 56 after immunization. At termination of the experiment (day 73), bone mineral density (BMD) was analyzed, paws were collected for histological examination, and sera were analyzed for markers of cartilage turnover and pro-inflammatory cytokines.

Results

Raloxifene and estradiol treatment, as well as endogenous estrogen, decreased the frequency of arthritis, prevented joint destruction and countered generalized osteoporosis. These effects were associated with lower serum levels of the pro-inflammatory cytokine IL-6.

Conclusions

This is the first study to show that raloxifene and estradiol can ameliorate established erosive arthritis and inflammation-triggered osteoporosis in this chronic arthritis model. We propose that treatment with raloxifene could be a beneficial addition to the treatment of postmenopausal RA.

The swollen joint, the thickened artery, and the smoking gun: tobacco exposure, citrullination and rheumatoid arthritis

Autoimmune diseases result from an interplay between susceptibility genes and environmental factors. These interacting etiopathogenetic components converge in a critical step preceding disease, the loss of tolerance to self. In this review, we examine the evidences linking tobacco smoking with the initiation and perpetuation of inflammation affecting both the synovial membrane and the endothelial lining in patients with rheumatoid arthritis. This disease is a compelling argument for the decisive role of environment in the triggering of a human autoimmune disease in genetically prone individuals.

Is the incidence of rheumatoid arthritis rising?: results from Olmsted County, Minnesota, 1955-2007

OBJECTIVE

To examine trends in the incidence and prevalence of rheumatoid arthritis (RA) from 1995 to 2007.

METHODS

To augment our preexisting inception cohort of patients with RA (1955-1994), we assembled a population-based incidence cohort of individuals >or=18 years of age who first fulfilled the American College of Rheumatology 1987 criteria for the classification of RA between January 1, 1995 and December 31, 2007 and a cohort of patients with prevalent RA on January 1, 2005. Incidence and prevalence rates were estimated and were age-and sex-adjusted to the white population in the US in 2000. Trends in incidence rates were examined using Poisson regression methods.

RESULTS

The 1995-2007 incidence cohort comprised 466 patients (mean age 55.6 years), 69% of whom were female and 66% of whom were rheumatoid factor positive. The overall age- and sex-adjusted annual RA incidence was 40.9/100,000 population. The age-adjusted incidence in women was 53.1/100,000 population (versus 27.7/100,000 population in men). During the period of time from 1995 to 2007, the incidence of RA increased moderately in women (P = 0.02) but not in men (P = 0.74). The increase was similar among all age groups. The overall age- and sex-adjusted prevalence on January 1, 2005 was 0.72% (95% confidence interval [95% CI] 0.66, 0.77), which is an increase when compared with a prevalence of 0.62% (95% CI 0.55, 0.69) in 1995 (P < 0.001). Applying the prevalence on January 1, 2005 to the US population in 2005 showed that an estimated 1.5 million US adults were affected by RA. This is an increase from the previously reported 1.3 million adults with RA in the US.

CONCLUSION

The incidence of RA in women appears to have increased during the period of time from 1995 to 2007. The reasons for this recent increase are unknown, but environmental factors may play a role. A corresponding increase in the prevalence of RA was also observed.

Environmental influences on risk for rheumatoid arthritis

PURPOSE OF REVIEW

To examine new environmental factors and provide updates on known risk factors for rheumatoid arthritis (RA) in the past 2 years (2006-2008). This review is timely given the expanding information on treatment, pathogenesis and genetic risk factors for RA.

RECENT FINDINGS

High consumption of red meat does not increase risk of RA, whereas alcohol intake may be protective. The role of vitamin D and oral contraceptives as modifiers of disease risk remains equivocal. Other factors associated with increased risk of RA include higher birthweight, living in the northeastern United States compared with other regions of the country, and lower socioeconomic status. Duration of breastfeeding is inversely associated with RA risk. Several studies have now demonstrated that anti-citrullinated protein antibody positive RA has a specific association with environmental risk factors such as smoking.

SUMMARY

Recent studies have increased our understanding of environmental exposures that modify risk for RA such as smoking and alcohol intake. Other factors such as birthweight, breastfeeding, socioeconomic status and region of birth have also been demonstrated to contribute to risk. ACPA status is associated with specific environmental factors and is therefore important to incorporate into present and future studies.

Biomarkers of inflammation and development of rheumatoid arthritis in women from two prospective cohort studies

OBJECTIVE

To examine the association of biomarkers of inflammation with preclinical rheumatoid arthritis (RA).

METHODS

A nested case-control study was performed using samples from 2 large, prospectively studied cohorts of women (the Women's Health Study [WHS] and the Nurses' Health Study [NHS]). Blood samples obtained prior to symptom onset in women who later developed RA were selected as incident RA cases, and 3 controls per case were randomly chosen, matched for age, menopausal status, postmenopausal hormone use, and day, time, and fasting status at the time of collection. Plasma was tested for levels of interleukin-6 (IL-6), soluble tumor necrosis factor receptor II (sTNFRII) (as a proxy for TNFalpha), and high-sensitivity C-reactive protein. Relationships between biomarkers and RA were assessed using conditional logistic regression models, adjusting for age, body mass index, smoking habits, ethnicity, and reproductive factors.

RESULTS

In 93 incident cases in the NHS and 77 incident cases in the WHS, the mean time between blood collection and the onset of RA symptoms was 5.2 years (range 0.3-12 years). Median IL-6 and sTNFRII levels were significantly higher in preclinical RA cases compared with matched controls in the NHS (P = 0.03 and P = 0.003, respectively) though not in the WHS. Pooled analysis of the NHS and WHS cohorts demonstrated significant association of sTNFRII with RA (relative risk 2.0 [95% confidence interval 1.1-3.6], P for trend = 0.004), and a modest association of IL-6 with RA (relative risk 1.4 [95% confidence interval 0.8-2.5], P for trend = 0.06).

CONCLUSION

Levels of sTNFRII, a biomarker typically associated with active RA, were elevated up to 12 years prior to the development of RA symptoms and were positively associated with incident RA in these nested case-control studies. Studies with repeated assessments of biomarkers prior to RA development may provide further insight into the timing of biomarker elevation in preclinical RA.

Women, men, and rheumatoid arthritis: analyses of disease activity, disease characteristics, and treatments in the QUEST-RA study

Introduction

Gender as a predictor of outcomes of rheumatoid arthritis (RA) has evoked considerable interest over the decades. Historically, there is no consensus whether RA is worse in females or males. Recent reports suggest that females are less likely than males to achieve remission. Therefore, we aimed to study possible associations of gender and disease activity, disease characteristics, and treatments of RA in a large multinational cross-sectional cohort of patients with RA called Quantitative Standard Monitoring of Patients with RA (QUEST-RA).

Methods

The cohort includes clinical and questionnaire data from patients who were seen in usual care, including 6,004 patients at 70 sites in 25 countries as of April 2008. Gender differences were analyzed for American College of Rheumatology Core Data Set measures of disease activity, DAS28 (disease activity score using 28 joint counts), fatigue, the presence of rheumatoid factor, nodules and erosions, and the current use of prednisone, methotrexate, and biologic agents.

Results

Women had poorer scores than men in all Core Data Set measures. The mean values for females and males were swollen joint count-28 (SJC28) of 4.5 versus 3.8, tender joint count-28 of 6.9 versus 5.4, erythrocyte sedimentation rate of 30 versus 26, Health Assessment Questionnaire of 1.1 versus 0.8, visual analog scales for physician global estimate of 3.0 versus 2.5, pain of 4.3 versus 3.6, patient global status of 4.2 versus 3.7, DAS28 of 4.3 versus 3.8, and fatigue of 4.6 versus 3.7 (P < 0.001). However, effect sizes were small-medium and smallest (0.13) for SJC28. Among patients who had no or minimal disease activity (0 to 1) on SJC28, women had statistically significantly higher mean values compared with men in all other disease activity measures (P < 0.001) and met DAS28 remission less often than men. Rheumatoid factor was equally prevalent among genders. Men had nodules more often than women. Women had erosions more often than men, but the statistical significance was marginal. Similar proportions of females and males were taking different therapies.

Conclusions

In this large multinational cohort, RA disease activity measures appear to be worse in women than in men. However, most of the gender differences in RA disease activity may originate from the measures of disease activity rather than from RA disease activity itself.

Geographic variation in rheumatoid arthritis incidence among women in the United States

BACKGROUND

The geographic variation in rheumatoid arthritis (RA) incidence in the United States is unknown.

METHODS

We studied residential region from January 1, 1921, to May 31, 1976, and RA risk in a prospective cohort of women, the Nurses' Health Study. Information on state of residence was collected at baseline in 1976 (when participants were aged 30-55 years) and on state of residence at birth, at age 15 years, and at age 30 years in 1992. Among 83,546 participants reporting residence for all 4 time points, 706 incident RA cases from June 1, 1976, to May 31, 2004, were confirmed by screening questionnaire and record review for American College of Rheumatology criteria. Residential region was classified as West, Midwest, mid-Atlantic, New England, and Southeast. Multivariate Cox proportional hazards regression models were used to assess relationships between region and RA risk, adjusting for age, smoking, body mass index, parity, breastfeeding, postmenopausal status, postmenopausal hormone use, father's occupation, race, and physical activity. Analyses were performed in participants who lived in the same regions, or moved, over time.

RESULTS

Compared with those in the West, women in New England had a 37% to 45% elevated risk of RA in multivariate models at each time point (eg, state of residence in 1976: rate ratio [RR], 1.42; 95% confidence interval [CI], 1.10-1.82). In analyses of women who lived in the same region at birth, age 15 years, and age 30 years, living in the Midwest was associated with greater risk (RR, 1.47; 95% CI, 1.05-2.05), as was living in New England (RR, 1.40; 95% CI, 0.98-2.00). Compared with living in the West at birth, age 15 years, and age 30 years, RA risk was higher in the East.

CONCLUSIONS

In this large cohort of US women, significant geographic variation in incident RA existed after controlling for confounders. Potential explanations include regional variation in behavioral factors, climate, environmental exposures, RA diagnosis, and genetic factors.

La contraception des adolescentes en France en 2007

The two main objectives of adolescence contraception are the eviction of involuntary pregnancies and the prevention of sexually transmitted infections. In France, in spite of our rich contraceptive arsenal and a widely spread information, the rate of voluntary termination of pregnancy keeps growing among the teenagers population--and this, probably because the gap between theoretical effectiveness and practice of contraception is particularly wide among the young people. Every contraceptive means can be used by teenagers; the best option being, it seems, the "double DUTCH", which consists of concomitant use of condoms and hormonal contraception. Most often, the consultation for contraception is the first gynaecological consultation. That is the reason why it is usually stressful for teenagers who dread undergoing a gynaecological examination. If this examination is not necessary for most of young patients, it is essential to create a trustful relationship and to make explicit the several contraceptive methods. During this consultation it is interesting to look for common teenage troubles like addiction to smoking and eating disorders. For any prescription of hormonal contraception, it is important to explain the benefits and the possible side effects, to stress the observance and to tell the teenager about the recommendations in case of forgetting. Concerning condom - the only efficient way of preventing sexually transmitted infections--, it is useful to talk about it in concrete and straightforward terms, to show its handling and to inform about risks of tearing. With this state of mind, an emergency contraception can be prescribed straightaway in order to make its use easier. Also, without any moralizing speech, the need for maturity must be emphasized as well as taking care of one's body with the aim of avoiding a premature pregnancy or any sexually transmitted infection. This consultation must be coupled with a close follow-up, availability and mutual confidence which are the main elements vouching for a good observance and consequently an efficient contraception.

Pathogenesis and therapy of rheumatoid arthritis

Rheumatoid arthritis is a chronic disabling disease affecting at least 1% of the population on a worldwide basis. Research aimed at understanding the pathogenesis of this disease led to the identification of TNFalpha as a major pro-inflammatory cytokine expressed in the inflamed joints of patients with rheumatoid arthritis. Subsequently, in vitro studies provided evidence to suggest that TNFalpha played an important role in driving the expression of additional pro-inflammatory cytokines, such as IL-1, GM-CSF, IL-6, and IL-8, in synovial cell cultures. Another important finding that confirmed the pathological significance of TNFalpha was that mice genetically engineered to overexpress TNFalpha spontaneously developed arthritis. Subsequently, the therapeutic effect TNFalpha blockade was tested in animal models prior to clinical trials in human patients, which provided unequivocal verification of the validity of TNFalpha as a therapeutic target. Anti-TNFalpha therapy is now accepted as a fully-validated treatment modality for rheumatoid arthritis.

The complex role of estrogens in inflammation

There is still an unresolved paradox with respect to the immunomodulating role of estrogens. On one side, we recognize inhibition of bone resorption and suppression of inflammation in several animal models of chronic inflammatory diseases. On the other hand, we realize the immunosupportive role of estrogens in trauma/sepsis and the proinflammatory effects in some chronic autoimmune diseases in humans. This review examines possible causes for this paradox. This review delineates how the effects of estrogens are dependent on criteria such as: 1) the immune stimulus (foreign antigens or autoantigens) and subsequent antigen-specific immune responses (e.g., T cell inhibited by estrogens vs. activation of B cell); 2) the cell types involved during different phases of the disease; 3) the target organ with its specific microenvironment; 4) timing of 17beta-estradiol administration in relation to the disease course (and the reproductive status of a woman); 5) the concentration of estrogens; 6) the variability in expression of estrogen receptor alpha and beta depending on the microenvironment and the cell type; and 7) intracellular metabolism of estrogens leading to important biologically active metabolites with quite different anti- and proinflammatory function. Also mentioned are systemic supersystems such as the hypothalamic-pituitary-adrenal axis, the sensory nervous system, and the sympathetic nervous system and how they are influenced by estrogens. This review reinforces the concept that estrogens have antiinflammatory but also proinflammatory roles depending on above-mentioned criteria. It also explains that a uniform concept as to the action of estrogens cannot be found for all inflammatory diseases due to the enormous variable responses of immune and repair systems.

Influence of male sex on disease phenotype in familial rheumatoid arthritis

OBJECTIVE

To examine sex differences in clinical, demographic, and genetic characteristics among a large cohort of patients with familial rheumatoid arthritis (RA).

METHODS

We studied 1,004 affected members of 467 Caucasian multicase RA families recruited from the North American Rheumatoid Arthritis Consortium. Standardized information about demographic and clinical characteristics was collected from all patients. Affected individuals also underwent radiography of the hands and were genotyped for markers in the HLA region. Sex differences were assessed using contingency table analysis (for categorical variables) and Student's t-tests for (continuous variables), and by multivariate logistic and linear regression analysis.

RESULTS

Male patients had a significantly later onset of RA, were more likely to be seropositive for RF, and had significantly higher titers of anti-cyclic citrullinated peptide (anti-CCP) antibodies compared with female patients, even after adjustment for covariates in multivariate analyses. Male patients were also significantly more likely to have a history of smoking and to be HLA-DRB1 shared epitope (SE) positive. Interestingly, female patients with an affected male sibling had significantly higher titers of anti-CCP antibodies and were more likely to be SE positive compared with female patients without affected male siblings. Multivariate analyses indicated that the presence of the SE did not fully explain the increased anti-CCP antibody titers observed in these families.

CONCLUSION

Sex has an important influence on the disease phenotype in RA, including the age at disease onset and autoantibody production. Furthermore, families with affected male members are characterized by higher titers of autoantibodies, particularly anti-CCP antibodies. Our results indicate that these findings are not fully explained by differences in exposure to tobacco smoke, presence of the HLA-DRB1 SE, or other HLA region genetic variation. Thus, other genetic or nongenetic factors also contribute to sex differences in the RA phenotype.

Rheumatoid factor seropositivity is inversely associated with oral contraceptive use in women without rheumatoid arthritis

OBJECTIVES

To examine whether oral contraceptive use is associated with the presence of serum rheumatoid factor in women of reproductive age without rheumatoid arthritis.

METHODS

304 women selected from parents of children who were at increased risk of developing type 1 diabetes were studied, because they were enriched with the human leucocyte antigen-DR4 allele, a susceptibility marker for both type 1 diabetes and rheumatoid arthritis. Participants visited a clinic where blood was drawn for rheumatoid factor testing, and exposure data were collected via questionnaires. A medical history and joint examination were performed to rule out rheumatoid arthritis. Participants and examiners were unaware of the participants' rheumatoid factor status at the time of examination and questionnaire.

RESULTS

Use of oral contraceptives at any time was inversely associated with rheumatoid factor positivity (adjusted odds ratio (OR) 0.2, 95% confidence interval (CI) 0.07 to 0.52) independent of age, education and smoking. Smoking > or = 20 pack-years was also associated with rheumatoid factor positivity (adjusted OR 56.38, 95% CI 4.31 to 736.98) compared with never smoking. Smoking 1-19 pack-years was not associated with a positive rheumatoid factor.

CONCLUSIONS

Our results suggest that oral contraceptive use, and possibly cigarette smoking, act early in the development of the immune dysregulation that occurs in rheumatoid arthritis.

Th2 immune deviation induced by pregnancy: the two faces of autoimmune rheumatic diseases

One of the most important immunological modifications during pregnancy is the Th1/Th2 shift, due to the progressive increase of progesterone and estrogens during pregnancy, which reach their peak-level in the third trimester of gestation. At high levels, estrogens seem mainly to suppress Th1 cytokines and stimulate Th2-mediated immunological responses as well as antibody production. For this reason Th1-mediated diseases, like rheumatoid arthritis (RA), tend to improve and Th2-mediated disease, like systemic lupus erythematosus (SLE), tend to worsen during pregnancy. SLE is the autoimmune rheumatic disease in which pregnancy most frequently occurs because it predominantly affects young females in their childbearing age. Other autoimmune rheumatic diseases, including RA, are less frequently observed during pregnancy due to their low female-to-male ratio and peak onset after the age of 40. This review is focused on the disease course, gestational outcome and management of patients with SLE and RA during pregnancy.

Do breast-feeding and other reproductive factors influence future risk of rheumatoid arthritis?: Results from the Nurses' Health Study

OBJECTIVE

To explore the contribution of female hormonal factors occurring prior to the onset of rheumatoid arthritis (RA), such as age at menarche, parity, age at first birth, breast-feeding, use of oral contraceptives (OCs), irregular menstrual cycles, and postmenopausal hormone (PMH) use, to the subsequent development of RA in a large female cohort.

METHODS

We studied female reproductive and hormonal risk factors for RA in a cohort of 121,700 women enrolled in the longitudinal Nurses' Health Study. The diagnosis of incident RA (between 1976 and 2002) in 674 women was confirmed by a connective tissue disease screening questionnaire and blinded medical record review for American College of Rheumatology criteria. Sixty percent of the patients with RA were rheumatoid factor positive. The relationship between potential risk factors, including age, age at menarche, parity, age at first birth, total lifetime history of breast-feeding, use of OCs, and irregular menstrual cycles and the multivariate-adjusted risk of RA was estimated using Cox proportional hazards models.

RESULTS

Using a multivariate model that adjusted for age, body mass index, smoking, parity, and other hormonal factors, we observed a strong trend for decreasing risk of RA with increasing duration of breast-feeding (P for trend = 0.001). For women who breast-fed (compared with parous women who did not breast-feed), the risk ratios (RRs) and 95% confidence intervals (95% CIs) were as follows: breast-feeding for < or =3 total months, RR 1.0 (95% confidence interval [95% CI] 0.8-1.2); for 4-11 total months, RR 0.9 (95% CI 0.7-1.1); for 12-23 total months, RR 0.8 (95% CI 0.6-1.0); and for > or =24 total months, RR 0.5 (95% CI 0.3-0.8). Very irregular menstrual cycles were associated with an increased risk of RA (RR 1.4, 95% CI 1.0-2.0). Age at menarche < or =10 years was associated with an increased risk of seropositive RA (RR 1.6, 95% CI 1.1-2.4) but not significantly associated with risk of RA. Parity, total number of children, age at first birth, and OC use were not associated with an increased risk of RA in this cohort.

CONCLUSION

In this large cohort, breast-feeding for >12 months was inversely related to the development of RA. This apparent effect was dose-dependent, with a significant trend toward lower risk with longer duration of breast-feeding. Irregular menstrual cycles and earlier age at menarche increased the risk of RA. Other reproductive hormonal factors were not associated with RA risk.

New insights into sexual functioning and fertility in rheumatic diseases

Sexuality is an often neglected area of quality of life in patients with rheumatic disease. Manifestations and symptoms of disease can impair sexual functioning, but this can be much improved by adequate intervention and counseling. Fertility is in general not reduced in rheumatic diseases, however, the time taken to achieve a pregnancy is often increased. An increased rate of pregnancy loss is observed in systemic lupus erythematosus and the antiphospholipid syndrome contributing to a reduced family size. Autoantibodies are present in most of the rheumatic diseases and can interfere with fertilization, implantation, embryonic development and placental function. Active disease disturbs the hypothalamic-pituitary-axis, giving rise to periods of gonadal dysfunction. Toxic effects of immunosuppressive drugs can induce transient or permanent gonadal failure in women and men.

Risk factors for rheumatoid arthritis

Both genetic and environmental factors contribute to the development of rheumatoid arthritis (RA). A long-term latent process often precedes the onset of arthritis. Hence, the ultimate causes of RA cannot be clarified by studying only the inflamed joints. Longitudinal studies focusing on risk factors are crucial in approaching the true aetiology. At present, most information gained from epidemiological studies is contradictory or vague. For instance, there is no consensus concerning the long-term effects of pregnancy or the putative protective role of oral contraceptives. There is no doubt that diet plays a role, but no specific nutrient has proved to be either protective or deleterious. Smoking is the only environmental risk factor that has been firmly verified epidemiologically for RA. It can be reasonably regarded as a contributory cause of RA. Studying the immunological effects of exposure to cigarette smoke may offer an opportunity to combine information from basic and epidemiological research to clarify the causal chains leading to RA.

[Non contraceptive benefits of oral contraception]

Both women and the medical profession underrate the non-contraceptive benefits of oral contraception, imbued as they are with its sole deleterious effects, such as thromboembolic ones, in particular. However, the pill is quite an efficient means of preventing against troubles of the menstrual cycle, with a betterment of cycle regularity, a diminishing of menstrual flux and a lowering of the frequency and the severity of primary dismenorrhoea. A review of the literature also demonstrates that oral contraception reduce by 40-50% the incidence of endometrial and ovarian cancer, inclusive of women with a previous history, or genetic predispositions. This effect is correlated with time of use and continues until 10 years or more after stopping taking the pill. Also, the positive part of the pill may well be considered as far as colorectal cancer is concerned, with a 40% or so reduction in risk, by means of decreasing bile acids in the colon. Other benefits of oral contraception have been documented, such as prevention of postmenopausal osteopenia when used during perimenopause, decrease in the incidence of adenofibromas, uterine fibromyomas, fibrocystic mastosis and uterine adnexial infections, and, finally, a favourable effect on acne. Preventive action of the pill on rheumatoid arthritis is debatable, the current feeling being that it diminishes severity as well as symptomatology more than risk of occurrence.

Smoking, gender and rheumatoid arthritis–epidemiological clues to etiology

OBJECTIVES

This study was undertaken to confirm and extend our earlier observation that gender is a biological effect modifier of smoking-rheumatoid arthritis (RA) relationship in a diverse national survey sample in the United States.

METHODS

Smoking history of 644 cases of RA and 1509 geographically matched general population controls were compared using weighted logistic regression.

RESULTS

There were 644 respondents with RA (cases) and 1509 geographically matched controls. Cases were significantly younger, less educated, more likely to be single and female than controls. Among cases 57% were smokers while among controls 49% smoked. Among women, after adjusting for age, hysterectomy had an age adjusted odds ratio 1.45, (95% CI 0.99-2.10) and menopause an adjusted odds ratio 1.18 (95% CI 0.99-2.10) were associated with smoking. In univariable analysis ever-smoking was associated with increased risk of RA (odds ratio 1.34, 95% CI 1.0-1.81). Among the strata of smokers, there was an increasing gradient of risk with increasing exposure to smoking (P = 0.041). In separate multivariable models, smoking increased the risk in men (odds ratio 2.29, 95% CI 1.35-3.90) while in women the risk was not elevated (odds ratio 0.98, 95% CI 0.67-1.42). After adjusting for the statistically significant interaction both female gender (odds ratio 2.30, 95% CI 1.39-3.83) and having ever smoked (odds ratio 2.31, 95% CI 1.36-3.94) emerged as significant risk factors for RA.

CONCLUSIONS

Gender interacts with smoking in by an unknown mechanism to lead to differential risk of RA.