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

Estrogen and other female reproductive risk factors are not strongly associated with the development of rheumatoid arthritis in elderly women

OBJECTIVE

Endogenous and exogenous reproductive hormones have been associated with rheumatoid arthritis (RA) in women, but data are inconsistent and no studies have assessed RA risk factors exclusively in elderly women.

METHODS

The authors examined the association between reproductive factors, exogenous hormone exposure, and RA in a prospective cohort study of 31,336 Iowa women who were aged 55 to 69 years at cohort baseline in 1986.

RESULTS

During 11 years of follow-up, 158 incident cases of RA were identified and validated. Age at last pregnancy (P trend =.01) and age at menopause (P trend =.03) were inversely associated with RA, whereas a history of polycystic ovary syndrome (relative risk [RR], 2.58; 95% confidence interval [CI], 1.06 to 6.30), endometriosis (RR, 1.72; 95% CI, 0.93 to 3.18), and former use of hormone replacement therapy (RR, 1.47; 95% CI, 1.04 to 2.06) were positively associated with RA. In multivariate analysis models, a history of polycystic ovary syndrome remained the most consistent predictor of RA, whereas the RRs for other factors attenuated.

CONCLUSION

Few reproductive factors showed a strong or statistically significant association with RA in elderly women. The association of polycystic ovary syndrome may be indicative of perturbations of endocrine-immune activity that may influence the development of RA. This prospective cohort study adds to the understanding of the potential contribution of hormonal factors to the cause of RA in older women.

Smoking-gender interaction and risk for rheumatoid arthritis

The present case-control study was conducted to investigate the relationship between smoking and rheumatoid arthritis, and to investigate formally the interaction between sex, smoking, and risk for developing rheumatoid arthritis. The study was performed in the Central District of Finland. Cases were patients with rheumatoid arthritis and the control group was a random sample of the general population. Logistic regression models were used to evaluate the effect of smoking on risk for rheumatoid arthritis, after adjusting for the effects of age, education, body mass index, and indices of general health and pain. Overall, 1095 patients with rheumatoid arthritis and 1530 control individuals were included. Patients were older, less well educated, more disabled, and had poorer levels of general health as compared with control individuals (all P < 0.01). Preliminary analyses revealed the presence of substantial statistical interaction between smoking and sex (P < 0.001). In separate multivariable analyses, past history of smoking was associated with increased risk for rheumatoid arthritis overall in men (odds ratio 2.0, 95% confidence interval 1.2-3.2) but not in women. Among men, this effect was seen only for rheumatoid factor-positive rheumatoid arthritis. There were significant interactions between smoking and age among women but not among men. We conclude that sex is a biologic effect modifier in the association between smoking and rheumatoid arthritis. The role of menopause in the etiology of rheumatoid arthritis merits further research.

Hormone replacement therapy in rheumatoid arthritis is associated with lower serum levels of soluble IL-6 receptor and higher insulin-like growth factor 1

Hormone replacement therapy (HRT) modulates the imbalance in bone remodeling, thereby decreasing bone loss. Sex hormones are known to influence rheumatic diseases. The aim of this study was to investigate the effects of HRT on the serum levels of hormones and cytokines regulating bone turnover in 88 postmenopausal women with active rheumatoid arthritis (RA) randomly allocated to receive HRT plus calcium and vitamin D3 or calcium and vitamin D3 alone for 2 years. An increase in estradiol (E2) correlated strongly with improvement of bone mineral density in the hip (P < 0.001) and lumbar spine (P < 0.001). Both baseline levels and changes during the study of IL-6 and erythrocyte sedimentation rate were correlated positively (P < 0.001). HRT for 2 years resulted in an increase of the bone anabolic factor, insulin-like growth factor 1 (IGF-1) (P < 0.05) and a decrease of serum levels of soluble IL-6 receptor (sIL-6R) (P < 0.05), which is known to enhance the biological activity of IL-6, an osteoclast-stimulating and proinflammatory cytokine. Baseline levels of IL-6 and IGF-1 were inversely associated (P < 0.05), and elevation of IGF-1 was connected with decrease in erythrocyte sedimentation rate (P < 0.05) after 2 years. Interestingly, increase in serum levels of E2 was associated with reduction of sIL-6R (P < 0.05) and reduction of sIL-6R was correlated with improved bone mineral density in the lumbar spine (P < 0.05). The latter association was however not significant after adjusting for the effect of E2 (P = 0.075). The influences of IGF-1 and the IL-6/sIL-6R pathways suggest possible mechanisms whereby HRT may exert beneficial effects in RA. However, to confirm this hypothesis future and larger studies are needed.

Epidemiology and genetics of rheumatoid arthritis

The prevalence of rheumatoid arthritis (RA) is relatively constant in many populations, at 0.5-1.0%. However, a high prevalence of RA has been reported in the Pima Indians (5.3%) and in the Chippewa Indians (6.8%). In contrast, low occurrences have been reported in populations from China and Japan. These data support a genetic role in disease risk. Studies have so far shown that the familial recurrence risk in RA is small compared with other autoimmune diseases. The main genetic risk factor of RA is the HLA DRB1 alleles, and this has consistently been shown in many populations throughout the world. The strongest susceptibility factor so far has been the HLA DRB1*0404 allele. Tumour necrosis factor alleles have also been linked with RA. However, it is estimated that these genes can explain only 50% of the genetic effect. A number of other non-MHC genes have thus been investigated and linked with RA (e.g. corticotrophin releasing hormone, oestrogen synthase, IFN-gamma and other cytokines). Environmental factors have also been studied in relation to RA. Female sex hormones may play a protective role in RA; for example, the use of the oral contraceptive pill and pregnancy are both associated with a decreased risk. However, the postpartum period has been highlighted as a risk period for the development of RA. Furthermore, breastfeeding after a first pregnancy poses the greatest risk. Exposure to infection may act as a trigger for RA, and a number of agents have been implicated (e.g. Epstein-Barr virus, parvovirus and some bacteria such as Proteus and Mycoplasma). However, the epidemiological data so far are inconclusive. There has recently been renewed interest in the link between cigarette smoking and RA, and the data presented so far are consistent with and suggestive of an increased risk.

The epidemiology of rheumatoid arthritis

Studies of the descriptive epidemiology of RA indicate a population prevalence of 0.5% to 1% and a highly variable annual incidence (12-1200 per 100,000 population) depending on gender, race/ethnicity, and calendar year. Secular trends in RA incidence over time have been shown in several studies, supporting the hypothesis of a host-environment interaction. People with RA have a significantly increased risk of death compared with age- and sex-matched controls without RA from the same community. The determinants of this excess mortality remain unclear; however, reports suggest increased risk from gastrointestinal, respiratory, cardiovascular, infectious, and hematologic diseases among RA patients compared with controls. Despite extensive epidemiologic research, the etiology of RA is unknown. Several risk factors have been suggested as important in the development or progression of RA. These include genetics, infectious agents, oral contraceptives, smoking, and formal education. Epidemiologic research is an essential contributor to our understanding of RA.

Involvement of the hypothalamic--pituitary--adrenal/gonadal axis and the peripheral nervous system in rheumatoid arthritis: viewpoint based on a systemic pathogenetic role

From the compendium presented above, the following statements become evident: 1) Inappropriately low secretion of cortisol in relation to inflammation is a typical feature of the inflammatory disease in patients with RA. 2) The secretion of adrenal androgens is significantly reduced, which is a problem in postmenopausal women and elderly men due to a lack of downstream sex hormones. 3) Serum levels of testosterone are markedly reduced in RA. 4) Sympathetic nerve fibers are markedly reduced in the synovial tissue of patients with RA, whereas proinflammatory sensory fibers (substance P) are present. 5) Substance P serves to continuously sense painful stimuli in the periphery, and the nociceptive input from the inflamed joint shows a large amplification in the spinal cord. This leads to continuous pain with stabilization of the afferent sensory input and continuous release of proinflammatory substance P into the lumen of the joint. From these facts it is obvious that alterations of the systemic antiinflammatory feedback systems contribute significantly to the pathogenesis of RA. Disease therapy directed at these alterations must provide a mechanism to replace the adrenal glands (glucocorticoids), the gonadal glands (androgens), and the sympathetic nervous system (adenosine increase by low-dose MTX, sulfasalazine, and salicylates) in order to integrate their immunosuppressive effects at the local site of synovial inflammation. Although local processes of the adaptive immune system are important in pathogenesis in the acute phase of RA, these mechanisms may be less important during the chronic phase of the disease in the absence of a specific trigger. We believe that a defect of systemic antiinflammatory feedback systems is an important factor in the perpetuation of RA. This review reinforces the belief that combined therapeutic approaches on a neuroendocrine immune basis are of crucial importance in a pathogenetically oriented therapy of RA.

Health benefits of oral contraceptives

A sizeable literature corroborates the multiple health benefits of oral contraceptive use. The first estrogen/progestin combination pills were marketed to treat a variety of menstrual disorders. Although currently used oral contraceptives no longer carry FDA-approved labeling for these indications, they remain important therapeutic options for a variety of gynecologic conditions. Well-established gynecologic benefits include a reduction in dysmenorrhea and menorrhagia, iron-deficiency anemia, ectopic pregnancy, and PID. Although older, higher-dose pills reduced the incidence of ovarian cysts, low-dose pills suppress follicular activity less consistently. Nevertheless, cycle-related symptoms, including functional cysts, dysmenorrhea, chronic pelvic pain, and ovulation pain (mittelschmerz), generally improve. Women with polycystic ovary syndrome note improvement in bleeding patterns and a reduction in acne and hirsutism. Symptoms from endometriosis also improve with oral contraceptive therapy. Current data suggest that oral contraceptive therapy increases bone density and that past use decreases fracture risk. Oral contraceptives also improve acne, a major health concern of young women. Oral contraceptives provide lasting reduction in the risk of two serious gynecologic malignancies--ovarian and endometrial cancer. The data with respect to ovarian cancer are compelling enough to recommend the use of oral contraceptives to women at high risk by virtue of family history, positive carrier status of the BRCA mutations, or nulliparity, even if contraception is not required. Health care providers must counsel women regarding these benefits to counteract deeply held public attitudes and misconceptions regarding oral contraceptive use. Messages should focus on topics of interest to particular groups of women. The fact that oral contraceptives increase bone mineral density and reduce ovarian cancer is of great interest to women in their forties and helps influence use and compliance in this group. In contrast, the beneficial effects of oral contraceptives on acne resonates with younger women. Getting the good news out about the benefits of oral contraceptives will enable more women to take advantage of their positive health effects.

Hormonal alterations in rheumatoid arthritis, including the effects of pregnancy

A number of hormonal abnormalities are present in RA patients. A major theme of these abnormalities seems to be that deficiencies in the production or action of gonadal (estrogens and androgens) and adrenal (corticosteroids and DHEA) hormones may be involved in regulating the onset, severity, and progression of RA. Differences in RA incidence and activity in the pregnant and postpartum periods provide the strongest support for this view. Hormonal changes during these periods clearly have the potential to exert profound effects on RA incidence and activity. The effect of pregnancy on RA activity is actually greater than the effect of some of the newer therapeutic agents. The striking increase in corticosteroids, estrogen, and progesterone during pregnancy may suppress RA onset or activity through the regulation of production or action of cytokines such as TNF alpha, IL-1, IL-6, IL-12, and IL-10. The relative adrenal- and gonadal-deficient environment of the postpartum period further supports the view that hormonal deficiencies predispose to the development or increased activity of RA. These observations justify the search for hormonal abnormalities in RA patients outside the pregnancy and postpartum periods. In particular, further studies on the period before the onset of disease are needed. Additional evidence does exist that a functional abnormality in the adrenal glands in RA patients results in dysregulation of corticosteroid and DHEA production. These abnormalities seem to be linked to aging and disease activity. It is still not established whether these abnormalities are primary or secondary, although data indicating adrenal hypofunction before the development of RA or within the first year of disease activity suggest a primary abnormality. Several hormonal abnormalities seem to be restricted by gender and age, particularly around perimenopause and menopause. These age- and gender-influenced effects may be the cause of some of the contradictory data reviewed here. Studies in the future should make greater efforts to segregate study populations by age, gender, and reproductive status. The identification of the specific hormonal abnormalities and patient populations that are at risk is important, because these factors may allow new therapeutic approaches that are less toxic than current regimens.

Sex hormone adjuvant therapy in rheumatoid arthritis

RA is an autoimmune rheumatic disorder resulting from the combination of several predisposing factors, including the relation between epitopes of possible triggering agents and histocompatibility epitopes, the status of the stress response system, and the sex hormone status. Estrogens are implicated as enhancers of humoral immunity, and androgens and progesterone are natural immune suppressors. Sex hormone concentrations have been evaluated in RA patients before glucocorticoid therapy and have frequently been found to be altered, especially in premenopausal women and male patients. In particular, low levels of gonadal and adrenal androgens (testosterone and DHT, DHEA and DHEAS) and a reduced androgen:estrogen ratio have been detected in body fluids (i.e., blood, synovial fluid, smears, saliva) of male and female RA patients. These observations support a possible pathogenic role for the decreased levels of the immune-suppressive androgens. Exposure to environmental estrogens (estrogenic xenobiotics), genetic polymorphisms of genes coding for hormone metabolic enzymes or receptors, and gonadal disturbances related to stress system activation (hypothalamic-pituitary-adrenocortical axis) and physiologic hormonal perturbations such as during aging, the menstrual cycle, pregnancy, the postpartum period, and menopause may interfere with the androgen:estrogen ratio. Sex hormones might exert their immune-modulating effects, at least in RA synovitis, because synovial macrophages, monocytes, and lymphocytes possess functional androgen and estrogen receptors and may metabolize gonadal hormones. The molecular basis for sex hormone adjuvant therapy in RA is thus experimentally substantiated. By considering the well-demonstrated immune-suppressive activities exerted by androgens, male hormones and their derivatives seem to be the most promising therapeutic approach. Recent studies have shown positive effects of androgen replacement therapy at least in male RA patients, particularly as adjuvant treatment. Interestingly, the increase in serum androgen metabolism induced by RA treatment with CSA should be regarded as a possible marker of androgen-mediated immune-suppressive activities exerted by CSA, at least in RA and at the level of sensitive target cells and tissues (i.e., synovial macrophages). The absence of altered serum levels of estrogens in RA patients and the reported immune-enhancing properties exerted by female hormones have represented a poor stimulus to test estrogen replacement therapy in RA. The different results obtained with OC use seem to depend on dose-related effects and the different type of response to estrogens in relation to the cytokine balance between Th1 cells (cellular immunity, i.e., RA) and Th2 cells (humoral immunity, i.e., SLE). The androgen replacement obtained directly (i.e., testosterone, DHT, DHEAS) or indirectly (i.e., antiestrogens) may represent a valuable concomitant or adjuvant treatment to be associated with other disease-modifying antirheumatic drugs (i.e., MTX, CSA) in the management of RA.

Hormonal and immunologic risk factors for the development of rheumatoid arthritis: an integrative physiopathogenetic perspective

Evidence indicates that women who are susceptible to premenopausal onset of RA and men each have identifiable risk factors or risk markers long before onset of the clinical disease. Accordingly, further definition of such predictive factors promises to identify persons who are susceptible to developing RA during preclinical phases. Like coronary artery disease, once risks for developing RA can be reliably quantitated, research in primary prevention should become a realistic objective. Disease prevention objectives are central to the public health strategy of the National Arthritis Action Plan and the US Public Health Service "Healthy People 2000" plan (2010 plan also proposed). The decade of arthritis and musculoskeletal diseases (2000-2010) offers an incentive to nurture a new paradigm of RA prevention. Further research in neuroendocrine, immunologic, and microvascular risk factors for the development of RA promises to unravel its complex physiopathogenetic mechanisms and permit identification of persons who are at high risk for developing this disease. Successful research in identifying reliable risk factors (or markers) can be expected to lead to prevention strategies. Effective programs in identifying persons susceptible to RA could lead to earlier control measures and significantly reduce the enormous burden of this common disease, which affects all segments of the population.

Elderly-onset rheumatoid arthritis

It is appreciated that age has a modifying effect on the clinical presentations of disorders such as hyperthyroidism and systemic lupus erythematosus. Similarly in EORA, there seems to be a change in the disease phenotype when it is compared to YORA. These differences are significant not only in highlighting the importance of the aging process on the immune system but also because they have medical and therapeutic implications. Improved classification has greatly improved our understanding and treatment of systemic lupus erythematosus, juvenile chronic arthritis, and seronegative spondyloarthropathies. Similarly, appreciating the differences, and similarities, between YORA and EORA should advance the choice of therapeutic options and potentially move closer to defining pathogenesis and origin.

Menopause, oestrogens and arthritis

The menopause coincides with the appearance of many of the common arthritic conditions and with the lessening of severity of others such as SLE. The hormonal changes that occur may modulate these diseases. Thus, hormonal manipulation may have either beneficial or detrimental effects on the incidence and activity of a number of common joint diseases. We review the evidence regarding the effect of the menopause and oestrogen replacement therapy on the pathogenesis, incidence and prevalence and disease activity of osteoarthritis, rheumatoid arthritis, systemic lupus erythematosus and carpal tunnel syndrome.

Linkage of a marker in intron D of the estrogen synthase locus to rheumatoid arthritis

OBJECTIVE

To test for the presence of linkage of the estrogen synthase (CYP19) locus to rheumatoid arthritis (RA) in affected sibling pair (ASP) families.

METHODS

Two data sets of RA ASPs (225 ASPs and 107 ASPs) were genotyped for a polymorphic tetranucleotide marker at the CYP19 locus using fluorescence-based semiautomated genotyping technology. Evidence of linkage was assessed by estimating allele sharing (identical by descent) in affected sibling pairs. The effect of this locus was also examined in patient subgroups stratified by sex and by age at disease onset.

RESULTS

An increase in allele sharing at the CYP19 locus was observed in the first data set of 225 ASPs (logarithm of odds [LOD] 0.8; P = 0.04). There was also an increase in allele sharing in a second data set, but this did not reach statistical significance (LOD 0.34; P = 0.1). The highest increase in allele sharing was seen in patients with an age at disease onset that was >50 years (LOD 1.1; P = 0.02).

CONCLUSION

An increase in allele sharing at the CYP19 locus has been demonstrated in 2 large samples of RA ASPs. The evidence for linkage was strongest in patients with an age at onset that was >50 years, which suggests that this locus may be a susceptibility locus for developing RA later in life. These data provide preliminary evidence that CYP19 may have a role in RA susceptibility.

Hormonal regulation of tumor necrosis factor-alpha, interleukin-12 and interleukin-10 production by activated macrophages. A disease-modifying mechanism in rheumatoid arthritis and systemic lupus erythematosus?

Rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) frequently develop and progress in settings in which sympathoadrenomedullary and gonadal hormone levels are changing, e.g., during pregnancy, postpartum period, menopause, estrogen administration. This paper addresses the view that adrenal and gonadal hormonal deficiency facilitates excessive macrophage production of TNF-alpha and IL-12 that characterizes RA, whereas excessive estrogen action is suggested to play an essential role in the production of IL-10 in patients with SLE. Disease activity in SLE, in contrast to RA, appears to be associated with high-level production of IL-10, relative to the proinflammatory cytokines, TNF-alpha and IL-12. Accumulating data suggest that novel therapeutic approaches may ultimately be developed from continued investigation of the role of the neuroendocrine factors in RA and SLE.

Benefits and risks of oral contraceptives

The major benefits of modern low-dose oral contraceptives include relative safety and a high degree of efficacy, decreasing the need for abortion or surgical sterilization; reduced risks of bacterial (but not viral) pelvic inflammatory disease and of endometrial and ovarian cancer; improved menstrual regularity, with less dysmenorrhea and blood flow; and, when low-dose combination (not progestogen-only) oral contraceptives are used, reduced acne and hirsutism. Major risks are cardiovascular. Preliminary data from nonrandomized studies suggest that oral contraceptives containing third-generation progestogens are associated with increased risk of venous thromboembolism, particularly in carriers of the coagulation factor V Leiden mutation. The risk of arterial thrombosis, such as myocardial infarction or stroke, may be directly related to estrogen dose, particularly in women who have hypertension, smoke, or are >35 years old. Considering that only users aged >/=30 years who smoke >/=25 cigarettes/d have a higher estimated mortality rate than that of pregnant women, the benefits of oral contraceptives appear to outweigh their risks.

The lack of associations between rheumatoid arthritis and both nulliparity and infertility

OBJECTIVES

Rheumatoid arthritis (RA) is an autoimmune disease that occurs more commonly in women and frequently onsets in women of childbearing age. Pregnancy often causes disease remission, with a subsequent flare postpartum. Nulliparity may be a risk factor for RA, but the literature does not consistently report this finding. There may be a production of antibodies in women with RA that could lead to infertility, and subsequent nulliparity, but this has not been proved. We wanted to determine whether there was a relationship between nulliparity, infertility, oral contraceptive use, and adverse pregnancy outcome in women with newly diagnosed RA.

METHODS

Through a case control study, using a mailed questionnaire, we compared the fertility and pregnancy outcome histories of 34 women between the ages of 19 and 44 years with recent-onset RA with 68 healthy controls matched for age and marital status. The response rate was 97%. A review of the literature also was performed to study the associations between RA and infertility and nulliparity, using Medline searching key references.

RESULTS

We found no association between infertility and the onset of RA. Seventy-one percent of women with RA and 68% of controls had been pregnant. There was a trend toward increased nulliparity in these patients, but the result was not statistically significant (odds ratio [OR], 1.4; P<.6). There were no differences in the number of children (2.6 v. 2.7; P<.6) and parity outcomes in the two groups. Age at first pregnancy was younger in the women with RA (22.6 v. 25.5 years; P<.008), but the education level was higher in the controls (P<.0001), which may explain these differences. Oral contraceptive use was lower in the RA women, but more RA women had long-term use (greater than or equal to 5 years), and neither result was statistically significant. Literature review shows that at best, there are weak negative associations between current estrogen use and RA, and no association with nulliparity and infertility.

CONCLUSIONS

It appears that infertility, the number of pregnancies, and pregnancy outcome are not strongly associated with the risk of developing RA in women of childbearing age. However, in this study there may have been selection biases in the women with RA and the controls that differentially could have affected their reproductive outcomes. Thus, a true association could have been missed. Most other published studies find no association between nulliparity and RA.