Impact and Timing of Smoking Cessation on Reducing Risk of Rheumatoid Arthritis Among Women in the Nurses' Health Studies

Air Pollution and Rheumatoid Arthritis Risk and Progression: Implications for the Mucosal Origins Hypothesis and Climate Change for RA Pathogenesis

PURPOSE OF REVIEW

The goal of this review paper is to summarize the main research and findings regarding air pollution and its association with the risk and progression of rheumatoid arthritis (RA).

RECENT FINDINGS

The most studied components of air pollution included particulate matter of ≤ 2.5 microns in diameter (PM2.5), PM10, carbon monoxide (CO), nitrogen dioxide (NO2), nitric oxide (NOx), sulfur dioxide (SO2), and ozone (O3). In addition, specific occupations and occupational inhalants have been investigated for RA risk. Several studies showed that increased exposure to air pollutants increased the risk of developing RA, particularly seropositive RA. There was evidence of gene-inhalant interactions for seropositive RA risk. Fewer studies have been conducted on RA disease activity and bone erosions. Some studies suggest that patients with RA-associated interstitial lung disease may have worse outcomes if exposed to air pollution. We summarized associations between air pollution and increased RA risk, including RA-associated interstitial lung disease. Relatively few studies investigated air pollution and RA disease activity or other outcomes. These results suggest an important role of air pollution for seropositive RA development and suggest that climate change could be a driver in increasing RA incidence as air pollution increases.

Galangin: A Promising Flavonoid for the Treatment of Rheumatoid Arthritis-Mechanisms, Evidence, and Therapeutic Potential

Rheumatoid Arthritis (RA) is a chronic autoimmune disease characterized by progressive joint inflammation and damage. Oxidative stress plays a critical role in the onset and progression of RA, significantly contributing to the disease's symptoms. The complex nature of RA and the role of oxidative stress make it particularly challenging to treat effectively. This article presents a comprehensive review of RA's development, progression, and the emergence of novel treatments, introducing Galangin (GAL), a natural flavonoid compound sourced from various plants, as a promising candidate. The bioactive properties of GAL, including its anti-inflammatory, antioxidant, and immunomodulatory effects, are discussed in detail. The review elucidates GAL's mechanisms of action, focusing on its interactions with key targets such as inflammatory cytokines (e.g., TNF-α, IL-6), enzymes (e.g., SOD, MMPs), and signaling pathways (e.g., NF-κB, MAPK), which impact inflammatory responses, immune cell activation, and joint damage. The review also addresses the lack of comprehensive understanding of potential treatment options for RA, particularly in relation to the role of GAL as a therapeutic candidate. It highlights the need for further research and clinical studies to ascertain the effectiveness of GAL in RA treatment and to elucidate its mechanisms of action. Overall, this review provides valuable insights into the potential of GAL as a therapeutic option for RA, shedding light on its multifaceted pharmacological properties and mechanisms of action, while suggesting avenues for future research and clinical applications.

Fine Particulate Matter Components and Risk of Rheumatoid Arthritis: A Large General Canadian Open Cohort Study

OBJECTIVE

Exposure to fine particulate matter (PM2.5) has been linked to many diseases. However, it remains unclear which PM2.5 chemical components for these diseases, including rheumatoid arthritis (RA), are more harmful. This study aimed to assess potential associations between PM2.5 components and RA and quantify the individual effects of each chemical component on RA risk.

METHODS

An open cohort of 11,696,930 Canadian adults was assembled using Ontario administrative health data from January 2007 onward. Individuals were followed until RA onset, death, emigration from Ontario, or the end of the study (December 2019). Incident RA cases were defined by physician billing and hospitalization discharge diagnostic codes. The average levels of PM2.5 components (ammonium, black carbon, mineral dust, nitrate, organic matter, sea salt, and sulfate) for 5 years before cohort entry were assigned to participants based on residential postal codes. A quantile g-computation and Cox proportional hazard models for time to RA onset were developed for the mixture of PM2.5 components and environmental overall PM2.5, respectively.

RESULTS

We identified 67,676 new RA cases across 130,934,256 person-years. The adjusted hazard ratios for the time to RA onset were 1.027 and 1.023 (95% confidence intervals 1.021-1.033 and 1.017-1.029) per every decile increase in exposures to all seven components and per 1 μg/m3 increase in the overall PM2.5, respectively. Ammonium contributed the most to RA onset in the seven components.

CONCLUSION

Exposure to PM2.5 components was modestly associated with RA risk. Public health efforts focusing on specific components (eg, ammonium) may be a more efficient way to reduce RA burden.

Prevention of Rheumatoid Arthritis in At-Risk Individuals: Current Status and Future Prospects

Early intervention has been the cornerstone of improving outcomes in patients with rheumatoid arthritis. Over the past decade, the boundaries have been pushed in an attempt to achieve effective prevention strategies in those who are at high risk of developing rheumatoid arthritis. Core risk factors including the presence of serum anti-citrullinated protein antibodies, arthralgia and subclinical inflammation on imaging are highly predictive of arthritis development. The influence of air pollution, diet and the role of microbiome on disease progression are less clear. In turn, therapeutic focus has shifted to an earlier pre-arthritis phase of the disease continuum where the clinically apparent arthritis may potentially be intercepted. Seven proof-of-concept interventional trials in at-risk individuals have been conducted so far. Whether true prevention of rheumatoid arthritis is possible remains elusive. Promising signals towards permanent disease modulation and improvement in symptom burden were seen with some immunomodulatory therapies, whilst others were unsuccessful. Long-term follow-up is required to ascertain a true effect. Looking forward, a better understanding of the natural history and underlying biological mechanisms of arthritis development and more accurate, validated risk stratification is needed.

The peculiar features, diversity and impact of citrulline-reactive autoantibodies

Since entering the stage 25 years ago as a highly specific serological biomarker for rheumatoid arthritis, anti-citrullinated protein antibodies (ACPAs) have been a topic of extensive research. This hallmark B cell response arises years before disease onset, displays interpatient autoantigen variability, and is associated with poor clinical outcomes. Technological and scientific advances have revealed broad clonal diversity and intriguing features including high levels of somatic hypermutation, variable-domain N-linked glycosylation, hapten-like peptide interactions, and clone-specific multireactivity to citrullinated, carbamylated and acetylated epitopes. ACPAs have been found in different isotypes and subclasses, in both circulation and tissue, and are secreted by both plasmablasts and long-lived plasma cells. Notably, although some disease-promoting features have been reported, results now demonstrate that certain monoclonal ACPAs therapeutically block arthritis and inflammation in mouse models. A wealth of functional studies using patient-derived polyclonal and monoclonal antibodies have provided evidence for pathogenic and protective effects of ACPAs in the context of arthritis. To understand the roles of ACPAs, one needs to consider their immunological properties by incorporating different facets such as rheumatoid arthritis B cell biology, environmental triggers and chronic antigen exposure. The emerging picture points to a complex role of citrulline-reactive autoantibodies, in which the diversity and dynamics of antibody clones could determine clinical progression and manifestations.

ABCD of IA: A multi-scale agent-based model of T cell activation in inflammatory arthritis

Biomaterial-based agents have been demonstrated to regulate the function of immune cells in models of autoimmunity. However, the complexity of the kinetics of immune cell activation can present a challenge in optimizing the dose and frequency of administration. Here, we report a model of autoreactive T cell activation, which are key drivers in autoimmune inflammatory joint disease. The model is termed a multi-scale Agent-Based, Cell-Driven model of Inflammatory Arthritis (ABCD of IA). Using kinetic rate equations and statistical theory, ABCD of IA simulated the activation and presentation of autoantigens by dendritic cells, interactions with cognate T cells and subsequent T cell proliferation in the lymph node and IA-affected joints. The results, validated with in vivo data from the T cell driven SKG mouse model, showed that T cell proliferation strongly correlated with the T cell receptor (TCR) affinity distribution (TCR-ad), with a clear transition state from homeostasis to an inflammatory state. T cell proliferation was strongly dependent on the amount of antigen in antigenic stimulus event (ASE) at low concentrations. On the other hand, inflammation driven by Th17-inducing cytokine mediated T cell phenotype commitment was influenced by the initial level of Th17-inducing cytokines independent of the amount of arthritogenic antigen. The introduction of inhibitory artificial antigen presenting cells (iaAPCs), which locally suppress T cell activation, reduced T cell proliferation in a dose-dependent manner. The findings in this work set up a framework based on theory and modeling to simulate personalized therapeutic strategies in IA.

Rheumatoid Arthritis: The Continuum of Disease and Strategies for Prediction, Early Intervention, and Prevention

Rheumatoid arthritis (RA) is known to include a pre-RA stage that can be defined as the presence of familial or genetic risk factors, biomarker abnormalities (eg, anticitrullinated protein antibodies [ACPA]), symptoms, and even abnormal imaging findings prior to the development of the onset of clinical RA with inflammatory arthritis that is apparent on physical examination. Indeed, there are multiple completed or ongoing retrospective case-control as well as prospective observational studies to identify the key biologic drivers of disease. Further, building on the predictive ability of combinations of biomarkers, symptoms, and imaging for future RA, there are multiple clinical trials completed, underway, or in development to identify approaches that may prevent, delay, or ameliorate future clinical RA in at-risk individuals. Importantly, however, although an effective preventive intervention has not yet been identified, at-risk individuals are being increasingly identified in clinical care; this presents a challenge of how to manage these individuals in clinical practice. This review will discuss the current understanding of the biology and natural history of RA development, nomenclature, and current models for prediction of future RA, as well as evaluate the current and ongoing clinical prevention trials with the overall goal to provide insights into the challenges and opportunities in the field of RA prevention. Moreover, this review will provide up-to-date options for clinical management of individuals at risk for RA.

Integrative non-pharmacological care for individuals at risk of rheumatoid arthritis

There is increasing knowledge in the recognition of individuals at risk for progression to rheumatoid arthritis (RA) before the clinical manifestation of the disease. This prodromal phase preceding the manifestation of RA may represent a "window of opportunity" for preventive interventions that may transform the clinical approach to this disease. However, limited evidence exists in support of effective interventions to delay the onset or even halt the manifestation of RA. Given the multifactorial nature of RA development and disease progression, the latest guidelines for established RA stress the use of integrative interventions and multidisciplinary care strategies, combining pharmacologic treatment with non-pharmacological approaches. Accordingly, individuals at risk of RA could be offered an integrative, multifactorial intervention approach. Current data point toward pharmacological intervention reverting the subclinical inflammation and delay in the disease onset. In addition, targeting life style modifiable factors (smoking cessation, dental health, physical activity, and diet) may presumably improve RA prognosis in individuals at risk, mainly by changes in epigenetics, autoantibodies, cytokines profiles, and microbiome. Nonetheless, the benefits of multidisciplinary interventions to halt the manifestation of RA in at-risk individuals remain unknown. As there is a growing knowledge of possible pharmacological intervention in the preclinical phase, this narrative review aims to provide a comprehensive overview of non-pharmacological treatments in individuals at risk of RA. Considering the mechanisms preceding the clinical manifestation of RA we explored all aspects that would be worth modifying and that would represent an integrative non-pharmacological care for individuals at risk of RA.

Rheumatoid arthritis, quantitative parenchymal lung features, and mortality among smokers

OBJECTIVES

There have been limited investigations of the prevalence and mortality impact of quantitative computed tomography (QCT) parenchymal lung features in rheumatoid arthritis (RA). We examined the cross-sectional prevalence and mortality associations of QCT features, comparing RA and non-RA participants.

METHODS

We identified participants with and without RA in COPDGene, a multicentre cohort study of current or former smokers. Using a k-nearest neighbor quantifier, high resolution CT chest scans were scored for percentage of normal lung, interstitial changes, and emphysema. We examined associations between QCT features and RA using multivariable linear regression. After dichotomizing participants at the 75th percentile for each QCT feature among non-RA participants, we investigated mortality associations by RA/non-RA status and quartile 4 vs quartiles 1-3 of QCT features using Cox regression. We assessed for statistical interactions between RA and QCT features.

RESULTS

We identified 82 RA cases and 8820 non-RA comparators. In multivariable linear regression, RA was associated with higher percentage of interstitial changes (β = 1.7 ± 0.5, p= 0.0008) but not emphysema (β = 1.3 ± 1.7, p= 0.44). Participants with RA and >75th percentile of emphysema had significantly higher mortality than non-RA participants (HR 5.86, 95%CI 3.75-9.13) as well as RA participants (HR 5.56, 95%CI 2.71-11.38) with ≤75th percentile of emphysema. There were statistical interactions between RA and emphysema for mortality (multiplicative p= 0.014; attributable proportion 0.53, 95%CI 0.30-0.70).

CONCLUSIONS

Using machine learning-derived QCT data in a cohort of smokers, RA was associated with higher percentage of interstitial changes. The combination of RA and emphysema conferred >5-fold higher mortality.

Epidemiology and Risk Factors for Rheumatoid Arthritis Development

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

Geospatial analysis of the hospitalisation rate of patients with rheumatoid arthritis in Hunan: a cross-sectional Chinese study

OBJECTIVE

Little is known about spatial variability of hospitalisation rate (HR) of patients with rheumatoid arthritis (RA) worldwide, especially in China.

METHODS

A cross-sectional study was conducted among patients with RA admitted to hospitals in Hunan Province. Global Moran's I and local indicators of spatial association were used to explore the geospatial pattern of the HR of patients with RA. Generalised estimating equation analysis and geographically weighted regression were used to identify the potential influencing factors of the HR of patients with RA.

RESULTS

There were a total of 11 599 admissions, and the average HR was 1.57 per 10 000 population in Hunan. We detected different cluster patterns of the HR among patients with RA by local indicators of spatial association. Age, ethnicity, average temperature, average temperature range, average rainfall, regions, gross domestic product per capita, and doctors and hospitals per 10 000 people were risk factors for the HR. However, only average temperature, gross domestic product per capita and hospitals per 10 000 people showed different regression coefficients on the HR in different counties. The increase in hospitals increased the probability of HR from east to west in Hunan with a positive coefficient, while temperature decreases increased the risk of HR from south to north negatively. Similarly, the growth of gross domestic product per capita decreased the probability of HR from southwest to northeast.

CONCLUSION

A non-random spatial distribution of the HR of patients with RA was demonstrated in Hunan, and average temperature, gross domestic product per capita and hospitals per 10 000 people showed different regression coefficients on the HR in different counties. Our study indicated that spatial and geostatistics may be useful approaches for further study among patients with RA.

Global, regional, and national burden of rheumatoid arthritis, 1990-2020, and projections to 2050: a systematic analysis of the Global Burden of Disease Study 2021

Background

Rheumatoid arthritis is a chronic autoimmune inflammatory disease associated with disability and premature death. Up-to-date estimates of the burden of rheumatoid arthritis are required for health-care planning, resource allocation, and prevention. As part of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021, we provide updated estimates of the prevalence of rheumatoid arthritis and its associated deaths and disability-adjusted life-years (DALYs) by age, sex, year, and location, with forecasted prevalence to 2050.

Methods

Rheumatoid arthritis prevalence was estimated in 204 countries and territories from 1990 to 2020 using Bayesian meta-regression models and data from population-based studies and medical claims data (98 prevalence and 25 incidence studies). Mortality was estimated from vital registration data with the Cause of Death Ensemble model (CODEm). Years of life lost (YLL) were calculated with use of standard GBD lifetables, and years lived with disability (YLDs) were estimated from prevalence, a meta-analysed distribution of rheumatoid arthritis severity, and disability weights. DALYs were calculated by summing YLLs and YLDs. Smoking was the only risk factor analysed. Rheumatoid arthritis prevalence was forecast to 2050 by logistic regression with Socio-Demographic Index as a predictor, then multiplying by projected population estimates.

Findings

In 2020, an estimated 17·6 million (95% uncertainty interval 15·8-20·3) people had rheumatoid arthritis worldwide. The age-standardised global prevalence rate was 208·8 cases (186·8-241·1) per 100 000 population, representing a 14·1% (12·7-15·4) increase since 1990. Prevalence was higher in females (age-standardised female-to-male prevalence ratio 2·45 [2·40-2·47]). The age-standardised death rate was 0·47 (0·41-0·54) per 100 000 population (38 300 global deaths [33 500-44 000]), a 23·8% (17·5-29·3) decrease from 1990 to 2020. The 2020 DALY count was 3 060 000 (2 320 000-3 860 000), with an age-standardised DALY rate of 36·4 (27·6-45·9) per 100 000 population. YLDs accounted for 76·4% (68·3-81·0) of DALYs. Smoking risk attribution for rheumatoid arthritis DALYs was 7·1% (3·6-10·3). We forecast that 31·7 million (25·8-39·0) individuals will be living with rheumatoid arthritis worldwide by 2050.

Interpretation

Rheumatoid arthritis mortality has decreased globally over the past three decades. Global age-standardised prevalence rate and YLDs have increased over the same period, and the number of cases is projected to continue to increase to the year 2050. Improved access to early diagnosis and treatment of rheumatoid arthritis globally is required to reduce the future burden of the disease.

Funding

Bill & Melinda Gates Foundation, Institute of Bone and Joint Research, and Global Alliance for Musculoskeletal Health.

Modifiable risk factors linked to the development of rheumatoid arthritis: evidence, immunological mechanisms and prevention

Rheumatoid Arthritis (RA) is a common autoimmune disease that targets the synovial joints leading to arthritis. Although the etiology of RA remains largely unknown, it is clear that numerous modifiable risk factors confer increased risk to developing RA. Of these risk factors, cigarette smoking, nutrition, obesity, occupational exposures and periodontal disease all incrementally increase RA risk. However, the precise immunological mechanisms by which these risk factors lead to RA are not well understood. Basic and translational studies have provided key insights into the relationship between inflammation, antibody production and the influence in other key cellular events such as T cell polarization in RA risk. Improving our general understanding of the mechanisms which lead to RA will help identify targets for prevention trials, which are underway in at-risk populations. Herein, we review the modifiable risk factors that are linked to RA development and describe immune mechanisms that may be involved. We highlight the few studies that have sought to understand if modification of these risk factors reduces RA risk. Finally, we speculate that modification of risk factors may be an appealing avenue for prevention for some at-risk individuals, specifically those who prefer lifestyle interventions due to safety and economic reasons.

Prevalence of rheumatoid arthritis in Greece: results from the national health examination survey EMENO

Rheumatoid arthritis (RA) is considered the most common form of autoimmune arthritis. The disease's prevalence is around 0.5-1% worldwide, but it seems to vary among different populations. The aim of this study was to estimate the prevalence of self-reported diagnosed RA in the general adult population in Greece. The data were derived from the Greek Health Examination Survey EMENO, a population-based survey performed between 2013 and 2016. Of the 6006 participants (response rate 72%), 5884 were eligible for this study. Prevalence estimates were calculated according to the study design. Prevalence of self-reported RA was estimated to be overall 0.5% (95% CI 0.4-0.7) being approximately three times higher in women than in men (0.7% vs 0.2%, p value = 0.004). A decrease in the prevalence of RA was observed in urban areas of the country. In contrast, higher disease rates were reported in individuals with lower socioeconomic status. Multivariable regression analysis showed that gender, age, and income were related to the occurrence of the disease. Osteoporosis and thyroid disease were the two comorbidities observed at statistically significant higher rates in individuals with self-reported RA. The prevalence of self-reported RA in Greece is similar to that reported in other European countries. Gender, age, and income are the main factors related to the disease's prevalence in Greece.

Prevention of rheumatoid arthritis: A systematic literature review of preventive strategies in at-risk individuals

BACKGROUND

Rheumatoid arthritis (RA) is an autoimmune disease characterized by symmetrical peripheral polyarthritis in the hands and/or feet, leading to long-term disability if not treated effectively. RA is preceded by a preclinical phase, in which genetically predisposed individuals accumulate environmental risk factors, and during which autoimmunity develops, followed by the emergence of non-specific signs and symptoms before arthritis becomes manifest. Early treatment in at-risk individuals - i.e. before the disease is fully established - has the theoretical potential to delay or prevent disease onset, with a positive impact on both patients' life and society.

OBJECTIVES

We aimed to understand the feasibility of preventive treatment in at-risk individuals, taking into account recently performed studies and ongoing clinical trials, as well as patient perspectives.

METHODS

We performed a systematic literature review (SLR) on Medline and Embase, searching articles published between 2010 and 2021 with the following key-words: "Rheumatoid arthritis", "arthralgia", "pre-treatment" or "prevent".

RESULTS

Our SLR identified a total of 1821 articles. Articles were independently screened by two researchers. A total of 14 articles were included after screening, and an additional 8 reports were manually included. We identified ten relevant clinical trials performed in at-risk individuals, or in individuals with undifferentiated inflammatory arthritis. Although no treatment was shown to prevent RA onset, early treatment with rituximab and abatacept delayed onset of full-blown RA, and both conventional and biological disease-modifying anti-rheumatic drugs (DMARDs) decreased disease-related physical limitations and increased DAS28-defined remission, at least temporarily.

CONCLUSIONS

This SLR demonstrates that early treatment of at-risk individuals may be effective in delaying RA onset, thereby decreasing disease-related limitations in individuals in the pre-clinical phase of RA. Whether this may ultimately lead to prevention of RA remains to be determined.

Recent advances in the treatment of systemic sclerosis associated interstitial lung disease

Connective tissue diseases (CTDs) are a heterogenous group of systemic inflammatory disorders. The development of connective tissue disease-associated interstitial lung disease (CTD-ILD) is a key complication associated with significant morbidity and mortality. The aim of this review is to explore the pathogenesis of CTD-ILD and summarize the recent evidence from clinical trials for novel treatment options, including the role of antifibrotics and immunomodulatory therapies with a focus on systemic sclerosis associated ILD. Further clinical trials are ongoing to explore combination therapies and more targeted therapeutic options. Clinicians remain faced with the difficult challenge of appropriately selecting patients who will benefit from the available therapies and timing the start of therapy at the most suitable part of the disease course.

The pathogenesis of rheumatoid arthritis

Significant recent progress in understanding rheumatoid arthritis (RA) pathogenesis has led to improved treatment and quality of life. The introduction of targeted-biologic and -synthetic disease modifying anti-rheumatic drugs (DMARDs) has also transformed clinical outcomes. Despite this, RA remains a life-long disease without a cure. Unmet needs include partial response and non-response to treatment in many patients, failure to achieve immune homeostasis or drug free remission, and inability to repair damaged tissues. RA is now recognized as the end of a multi-year prodromal phase in which systemic immune dysregulation, likely beginning in mucosal surfaces, is followed by a symptomatic clinical phase. Inflammation and immune reactivity are primarily localized to the synovium leading to pain and articular damage, but is also associated with a broader series of comorbidities. Here, we review recently described immunologic mechanisms that drive breach of tolerance, chronic synovitis, and remission.

Targeting Environmental Risks to Prevent Rheumatic Disease

Targeting environmental factors can be an important way to reduce the incidence of rheumatic diseases (RDs). Such approaches may be at population levels; furthermore, an emerging ability to identify an individual who is at very high risk for the development of a future RD can allow for personalized approaches to environmental modification for prevention. In this article, we will discuss challenges and opportunities to targeting environmental factors for the prevention of RDs.

Inhalant and Additional Mucosal-Related Environmental Risks for Rheumatoid Arthritis

Rheumatoid arthritis (RA) occurs as the result of a complex interplay of environmental factors in a genetically susceptible individual. There is considerable evidence that the lungs may serve as an initial site of tolerance loss in the generation of RA-related autoimmunity, and several environmental inhalant exposures and lung diseases have been associated with RA risk. There is additional evidence that immune and microbial dysregulation of other mucosal sites, including the oral and gastrointestinal mucosa, may contribute to the development of RA. Epidemiologic evidence linking mucosal exposures to various environmental insults as risk determinants in RA will be reviewed.

Acceptability of predictive testing for ischemic heart disease in those with a family history and the impact of results on behavioural intention and behaviour change: a systematic review

BACKGROUND

Tests to predict the development of chronic diseases in those with a family history of the disease are becoming increasingly available and can identify those who may benefit most from preventive interventions. It is important to understand the acceptability of these predictive approaches to inform the development of tools to support decision making. Whilst data are lacking for many diseases, data are available for ischemic heart disease (IHD). Therefore, this study investigates the willingness of those with a family history of IHD to take a predictive test, and the effect of the test results on risk-related behaviours.

METHOD

Medline, EMBASE, PsycINFO, LILACS and grey literature were searched. Primary research, including adult participants with a family history of IHD, and assessing a predictive test were included. Qualitative and quantitative outcomes measuring willingness to take a predictive test and the effect of test results on risk-related behaviours were also included. Data concerning study aims, participants, design, predictive test, intervention and findings were extracted. Study quality was assessed using the Standard Quality Assessment Criteria for Evaluating Research Papers from a Variety of Fields and a narrative synthesis undertaken.

RESULTS

Five quantitative and two qualitative studies were included. These were conducted in the Netherlands (n = 1), Australia (n = 1), USA (n = 1) and the UK (n = 4). Methodological quality ranged from moderate to good. Three studies found that most relatives were willing to take a predictive test, reporting family history (n = 2) and general practitioner (GP) recommendation (n = 1) as determinants of interest. Studies assessing the effect of test results on behavioural intentions (n = 2) found increased intentions to engage in physical activity and smoking cessation, but not healthy eating in those at increased risk of developing IHD. In studies examining actual behaviour change (n = 2) most participants reported engaging in at least one preventive behaviour, particularly medication adherence.

CONCLUSION

The results suggests that predictive approaches are acceptable to those with a family history of IHD and have a positive impact on health behaviours. Further studies are needed to provide a comprehensive understanding of predictive approaches in IHD and other chronic conditions.

Disease mechanisms in preclinical rheumatoid arthritis: A narrative review

In the last decades, the concept of preclinical rheumatoid arthritis (RA) has become established. In fact, the discovery that disease mechanisms start years before the onset of clinical RA has been one of the major recent insights in the understanding of RA pathogenesis. In accordance with the complex nature of the disease, preclinical events extend over several sequential phases. In a genetically predisposed host, environmental factors will further increase susceptibility for incident RA. In the initial steps of preclinical disease, immune disturbance mechanisms take place outside the joint compartment, namely in mucosal surfaces, such as the lung, gums or gut. Herein, the persistent immunologic response to altered antigens will lead to breach of tolerance and trigger autoimmunity. In a second phase, the immune response matures and is amplified at a systemic level, with epitope spreading and widening of the autoantibody repertoire. Finally, the synovial and bone compartment are targeted by specific autoantibodies against modified antigens, initiating a local inflammatory response that will eventually culminate in clinically evident synovitis. In this review, we discuss the elaborate disease mechanisms in place during preclinical RA, providing a broad perspective in the light of current evidence.

Epidemiology of rheumatoid arthritis: genetic and environmental influences

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic systemic disease characterized by articular involvement and extra-articular manifestations. The incidence and prevalence of the disease vary across populations, and there is an ongoing debate on whether a change of RA occurrence over time exists or is due to methodological issues and other biases. Moreover, the disease's onset is related to an interaction of genetic and environmental factors that influence its expression.

AREAS COVERED

This review explores the latest knowledge on RA epidemiology and the possible risk factors associated with its presentation to identify potential warning signs that may in the future help disease management.

EXPERT OPINION

Current epidemiological evidence suggests a significant impact of smoking, sex hormones, and lifestyle status in RA occurrence. However, the association between these variables has not yet been thoroughly studied. Still, their effect must be interpreted as they may present subsequently integral indicators for a more rational approach of the disease.

Preclinical Autoimmune Disease: a Comparison of Rheumatoid Arthritis, Systemic Lupus Erythematosus, Multiple Sclerosis and Type 1 Diabetes

The preclinical phase of autoimmune disorders is characterized by an initial asymptomatic phase of varying length followed by nonspecific signs and symptoms. A variety of autoimmune and inflammatory manifestations can be present and tend to increase in the last months to years before a clinical diagnosis can be made. The phenotype of an autoimmune disease depends on the involved organs, the underlying genetic susceptibility and pathophysiological processes. There are different as well as shared genetic or environmental risk factors and pathophysiological mechanisms between separate diseases. To shed more light on this, in this narrative review we compare the preclinical disease course of four important autoimmune diseases with distinct phenotypes: rheumatoid arthritis (RA), Systemic Lupus Erythematosus (SLE), multiple sclerosis (MS) and type 1 diabetes (T1D). In general, we observed some notable similarities such as a North-South gradient of decreasing prevalence, a female preponderance (except for T1D), major genetic risk factors at the HLA level, partly overlapping cytokine profiles and lifestyle risk factors such as obesity, smoking and stress. The latter risk factors are known to produce a state of chronic systemic low grade inflammation. A central characteristic of all four diseases is an on average lengthy prodromal phase with no or minor symptoms which can last many years, suggesting a gradually evolving interaction between the genetic profile and the environment. Part of the abnormalities may be present in unaffected family members, and autoimmune diseases can also cluster in families. In conclusion, a promising strategy for prevention of autoimmune diseases might be to address adverse life style factors by public health measures at the population level.

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

Background & Aims

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

Methods

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

Results

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

Conclusion

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

Pre-RA: Can early diagnosis lead to prevention?

Rheumatoid arthritis (RA) is currently diagnosed and treated once an individual displays the clinical findings of inflammatory arthritis (IA). However, growing evidence supports that there is a 'pre-RA' stage that can be identified through factors such as autoantibodies in absence of clinically apparent IA. In particular, biomarkers, including antibodies to citrullinated protein antigens (ACPA), demonstrate a high risk for future IA/RA, and multiple clinical trials have been developed to intervene in individuals in pre-RA to prevent or delay clinically apparent disease. Herein, we will discuss in more depth what is currently known about the natural history of RA, and the emerging possibility that early 'diagnosis' of RA-related autoimmunity followed by an intervention can lead to the delay or prevention of the first onset of clinically apparent RA.

Association of a Combination of Healthy Lifestyle Behaviors With Reduced Risk of Incident Systemic Lupus Erythematosus

OBJECTIVE

While previous studies have demonstrated an association between individual factors related to lifestyle and the risk of systemic lupus erythematosus (SLE), it is unclear how the combination of these factors might affect the risk of incident SLE. This study was undertaken to prospectively evaluate whether a combination of healthy lifestyle factors is associated with a lower risk of incident SLE and its subtypes (anti-double-stranded DNA [anti-dsDNA]-positive and anti-dsDNA-negative SLE).

METHODS

The study included 185,962 women from the Nurses' Health Study (NHS) and NHSII cohorts, among whom there were 203 incident cases of SLE (96 with anti-dsDNA-positive SLE, 107 with anti-dsDNA-negative SLE) during 4,649,477 person-years of follow-up. The Healthy Lifestyle Index Score (HLIS) was calculated at baseline and approximately every 2 years during follow-up, with scores assigned for 5 healthy lifestyle factors: alcohol consumption, body mass index, smoking, diet, and exercise. A time-varying Cox proportional hazards regression model was used to estimate the adjusted hazard ratios (HRs) with 95% confidence intervals (95% CIs) for the risk of SLE. In addition, the percentage of partial population attributable risk (PAR%) of SLE development was calculated.

RESULTS

A higher HLIS was associated with a lower risk of SLE overall (HR 0.81 [95% CI 0.71-0.94]) and a lower risk of anti-dsDNA-positive SLE (HR 0.78 [95% CI 0.63-0.95]). Women with ≥4 healthy lifestyle factors had the lowest risk of SLE overall (HR 0.42, 95% CI 0.25-0.70) and lowest risk of anti-dsDNA-positive SLE (HR 0.35, 95% CI 0.17-0.75) as compared to women with only 1 healthy behavior or no healthy behaviors. The PAR% of SLE development was 47.7% (95% CI 23.1-66.6%), assuming that the entire population had adhered to at least 4 healthy lifestyle behaviors.

CONCLUSION

These results indicate that the risk of developing SLE, a disease in which significant evidence of genetic involvement has been established, might be reduced by nearly 50% with adherence to modifiable healthy lifestyle behaviors.

Temperature might increase the hospital admission risk for rheumatoid arthritis patients in Anqing, China: a time-series study

Temperature has been studied in relation to many health outcomes. However, few studies have explored its effect on the risk of hospital admission for rheumatoid arthritis (RA). A distributed lag non-linear model (DLNM) was used to analyze associations between mean temperature, diurnal temperature range (DTR), temperature change between neighboring days (TCN), and daily admissions for RA from 2015 to 2019 in Anqing, China. Subgroup analyses based on age, gender, rheumatoid factors, and admission route were performed. In total, 1456 patients with RA were hospitalized. Regarding the cumulative-lag effects of extreme cold temperature (5th percentile = 3℃), the risks of admissions for RA were increased and highest at lag 0-11 (RR = 2.68, 95% CI: 1.23-5.86). Exposing to low (5th percentile = 1.9℃) and high (95th percentile = 14.2℃) DTRs both had increased risks of RA admission, with highest RRs of 1.40 (95% CI: 1.03-1.91) and 1.24 (95% CI: 1.0-1.53) at lag 0 day, respectively. As for TCN, the marginal risk of admission in RA patients was found when exposed to high TCN (95th percentile = 2.9℃) with the largest single-day effect at lag 10 (RR = 1.11, 95% CI: 1.01-1.23). In subgroup analyses, females were more susceptible to extreme cold temperature, low and high DTRs, and high TCN. In regard to extreme cold temperature, significant risk of hospital admission in females only appeared at lag 2 (RR = 1.48, 95% CI: 1.02-2.15) and lag 0-2 (RR = 2.35, 95% CI: 1.11-4.95). It is clear that RA patients exposed to changing temperature may increase risks of admission.

Etiology and Risk Factors for Rheumatoid Arthritis: A State-of-the-Art Review

Rheumatoid arthritis (RA) is the most common systemic inflammatory rheumatic disease. It is associated with significant burden at the patient and societal level. Extensive efforts have been devoted to identifying a potential cause for the development of RA. Epidemiological studies have thoroughly investigated the association of several factors with the risk and course of RA. Although a precise etiology remains elusive, the current understanding is that RA is a multifactorial disease, wherein complex interactions between host and environmental factors determine the overall risk of disease susceptibility, persistence and severity. Risk factors related to the host that have been associated with RA development may be divided into genetic; epigenetic; hormonal, reproductive and neuroendocrine; and comorbid host factors. In turn, environmental risk factors include smoking and other airborne exposures; microbiota and infectious agents; diet; and socioeconomic factors. In the present narrative review, aimed at clinicians and researchers in the field of RA, we provide a state-of-the-art overview of the current knowledge on this topic, focusing on recent progresses that have improved our comprehension of disease risk and development.

Should We Be Screening for and Treating Periodontal Disease in Individuals Who Are at Risk of Rheumatoid Arthritis?

There is increasing evidence supporting an association between periodontal disease (PD) and rheumatoid arthritis (RA), both mechanistically and clinically. Trials have shown that treating PD in people with RA may improve RA disease activity. Patients with musculoskeletal symptoms without arthritis, who test positive for cyclic-citrullinated protein antibodies, are at risk of RA (CCP+ at-risk), with seropositivity preceding arthritis onset by months or years. Importantly, there is evidence to suggest that periodontal inflammation may precede joint inflammation in CCP+ at-risk and, therefore, this could be a trigger for RA. There has been increased research interest in RA prevention and the phenotyping of the pre-RA disease phase. This review will examine the merits of identifying individuals who are CCP+ at-risk and performing screening for PD. In addition, we discuss how PD should be treated once identified. Finally, the review will consider future research needed to advance our understanding of this disease association.

Intake of marine n-3 polyunsaturated fatty acids and the risk of rheumatoid arthritis: protocol for a cohort study using data from the Danish Diet, Cancer and Health cohort and Danish health registers

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory joint disease with multifactorial aetiology. Smoking is a well-established lifestyle risk factor, but diet may also have an impact on the risk of RA. Intake of the major marine n-3 polyunsaturated fatty acids in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been hypothesised to lower the risk of RA due to their anti-inflammatory effects, although based on limited knowledge. Therefore, we aim to investigate the associations between dietary intake of EPA and DHA and the risk of incident RA.

METHODS AND ANALYSIS

A cohort study. The follow-up design will be based on data from the Danish Diet, Cancer and Health cohort, which was established between 1993 and 1997. The participants will be followed through record linkage using nationwide registers including the Danish Civil Registration System, the Danish National Patient Registry and the Danish National Prescription Registry using the unique Civil Personal Registration number. Time-to-event analyses will be conducted with RA as the outcome of interest. The participants will be followed from inclusion until date of RA diagnosis, death, emigration or end of follow-up. HRs with 95% CIs obtained using Cox proportional hazard regression models, with age as underlying time scale and adjustment for established and potential risk factors, will be used as measures of association.

ETHICS AND DISSEMINATION

The study has been approved by the Data Protection Committee of Northern Jutland, Denmark (2019-87) and the North Denmark Region Committee on Health Research Ethics (N-20190031). Study results will be disseminated through peer-reviewed journals and presentations at international conferences.

Interstitial Lung Disease in Connective Tissue Disease: A Common Lesion With Heterogeneous Mechanisms and Treatment Considerations

Connective tissue disease (CTD) related interstitial lung disease (CTD-ILD) is one of the leading causes of morbidity and mortality of CTD. Clinically, CTD-ILD is highly heterogenous and involves rheumatic immunity and multiple manifestations of respiratory complications affecting the airways, vessels, lung parenchyma, pleura, and respiratory muscles. The major pathological features of CTD are chronic inflammation of blood vessels and connective tissues, which can affect any organ leading to multi-system damage. The human lung is particularly vulnerable to such damage because anatomically it is abundant with collagen and blood vessels. The complex etiology of CTD-ILD includes genetic risks, epigenetic changes, and dysregulated immunity, which interact leading to disease under various ill-defined environmental triggers. CTD-ILD exhibits a broad spectra of clinical manifestations: from asymptomatic to severe dyspnea; from single-organ respiratory system involvement to multi-organ involvement. The disease course is also featured by remissions and relapses. It can range from stability or slow progression over several years to rapid deterioration. It can also present clinically as highly progressive from the initial onset of disease. Currently, the diagnosis of CTD-ILD is primarily based on distinct pathology subtype(s), imaging, as well as related CTD and autoantibodies profiles. Meticulous comprehensive clinical and laboratory assessment to improve the diagnostic process and management strategies are much needed. In this review, we focus on examining the pathogenesis of CTD-ILD with respect to genetics, environmental factors, and immunological factors. We also discuss the current state of knowledge and elaborate on the clinical characteristics of CTD-ILD, distinct pathohistological subtypes, imaging features, and related autoantibodies. Furthermore, we comment on the identification of high-risk patients and address how to stratify patients for precision medicine management approaches.

Challenges and Opportunities of Targeted Behavioral Interventions for Groups at Risk for Developing Rheumatoid Arthritis

Background: Rheumatoid arthritis (RA) is a serious autoimmune disease which causes painful, swollen joints and can impact quality of life and increase morbidity and mortality. There are several preclinical stages of RA that correspond to at-risk groups that include: genetic risk, risk from behaviors, elevation of RA-related autoantibodies, and early clinical disease manifestations such as undifferentiated arthritis. Early interventions are crucial to slowing progression to and potentially preventing RA onset. Modification of behaviors among at-risk individuals may decrease RA risk. There are several challenges and opportunities in implementing preventative behavioral interventions, which may vary within different at-risk groups. Methods: We performed a narrative review of the literature, including meta-analyses focused on RA risk-related behaviors as well as publications investigating the potential efficacy of behavioral modifications on RA risk. Results: There are multiple behavioral risk factors associated with RA, including smoking, obesity, low physical activity, low quality diet, and poor dental hygiene, which may contribute to progression to clinical RA. Meta-analyses have been performed for smoking, excess body weight, and physical activity. Likelihood of adopting behavioral modifications may increase as RA risk increases. Conclusions: Clinicians may be able to tailor preventative approaches to various RA at-risk groups to help reduce RA risk, but further research is needed. A better understanding of the relationship of behaviors with RA risk and optimized approaches to implementing behavioral changes may allow for clinicians to tailor their preventative approaches for at-risk individuals.

The pre-clinical phase of rheumatoid arthritis: From risk factors to prevention of arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease considered as a multistep process spanning from the interaction of genetic (e.g., shared epitope or non-HLA loci), environmental and behavioral risk factors (e.g., smoking) leading to breaking immune tolerance and autoimmune processes such as the production of autoantibodies (e.g., antibodies against citrullinated proteins ACPA or rheumatoid factors, RF), development of the first symptoms without clinical arthritis, and, finally, the manifestation of arthritis. Despite the typical joint involvement in established RA, the pathogenesis of the disease likely begins far from joint structures: in the lungs or periodontium in association with citrullination, intestinal microbiome, or adipose tissue, which supports normal findings in synovial tissue in ACPA+ patients with arthralgia. The presence of ACPA is detectable even years before the first manifestation of RA. The pre-clinical phase of RA is the period preceding clinically apparent RA with ACPA contributing to the symptoms without subclinical inflammation. While the combination of ACPA and RF increases the risk of progression to RA by up to 10 times, increasing numbers of novel autoantibodies are to be investigated to contribute to the increased risk and pathogenesis of RA. With growing knowledge about the course of RA, new aspiration emerges to cure and even prevent RA, shifting the "window of opportunity" to the pre-clinical phases of RA. The clinical definition of individuals at risk of developing RA (clinically suspect arthralgia, CSA) makes it possible to unify these at-risk individuals' clinical characteristics for "preventive" treatment in ongoing clinical trials using mostly biological or conventional synthetic disease-modifying drugs. However, the combination of symptoms, laboratory, and imaging biomarkers may be the best approach to select the correct target at-risk population. The current review aims to explore different phases of RA and discuss the potential of (non)pharmacological intervention aiming to prevent RA.

Roles of Postdiagnosis Accumulation of Morbidities and Lifestyle Changes in Excess Total and Cause-Specific Mortality Risk in Rheumatoid Arthritis

OBJECTIVE

To elucidate how postdiagnosis multimorbidity and lifestyle changes contribute to the excess mortality of rheumatoid arthritis (RA).

METHODS

We performed a matched cohort study among women in the Nurses' Health Study (1976-2018). We identified women with incident RA and matched each by age and year to 10 non-RA comparators at the RA diagnosis index date. Specific causes of death were ascertained via death certificates and medical record review. Lifestyle and morbidity factors were reported biennially; 61 chronic conditions were combined into the Multimorbidity Weighted Index (MWI). After adjusting for baseline confounders, we used inverse probability weighting analysis to examine the mediating influence of postindex MWI scores and lifestyle factors on total, cardiovascular, and respiratory mortality, comparing women with RA to their matched comparators.

RESULTS

We identified 1,007 patients with incident RA and matched them to 10,070 non-RA comparators. After adjusting for preindex confounders, we found that hazard ratios (HRs) and 95% confidence intervals (95% CIs) were higher for total mortality (HR 1.46 [95% CI 1.32, 1.62]), as well as cardiovascular (HR 1.54 [95% CI 1.22, 1.94]) and respiratory (HR 2.75 [95% CI 2.05, 3.71]) mortality in patients with RA compared to non-RA comparators. Adjusting for postindex lifestyle factors (physical activity, body mass index, diet, smoking) attenuated but did not substantially account for this excess RA mortality. After additional adjustment for postindex MWI scores, patients with RA had HRs of 1.18 (95% CI 1.05, 1.32) for total, 1.19 (95% CI 0.94, 1.51) for cardiovascular, and 1.93 (95% CI 1.42, 2.62) for respiratory mortality.

CONCLUSION

We found that MWI scores substantially accounted for the excess total and cardiovascular mortality among women with RA. This finding underscores the importance of monitoring for the total disease burden as a whole in monitoring patients with RA.

Rheumatoid Arthritis Pathogenesis, Prediction, and Prevention: An Emerging Paradigm Shift

Rheumatoid arthritis (RA) is currently diagnosed and treated when an individual presents with signs and symptoms of inflammatory arthritis (IA) as well as other features, such as autoantibodies and/or imaging findings, that provide sufficient confidence that the individual has RA-like IA (e.g., meeting established classification criteria) that warrants therapeutic intervention. However, it is now known that there is a stage of seropositive RA during which circulating biomarkers and other factors (e.g., joint symptoms) can be used to predict if and when an individual who does not currently have IA may develop future clinically apparent IA and classifiable RA. Indeed, the discovery of the "pre-RA" stage of seropositive disease has led to the development of several clinical trials in which individuals are studied to identify ways to delay or prevent the onset of clinically apparent IA/RA. This review focuses on several issues pertinent to understanding the prevention of RA. These include discussion of the pathogenesis of pre-RA development, prediction of the likelihood and timing of future classifiable RA, and a review of completed and ongoing clinical trials in RA prevention. Furthermore, this review discusses challenges and opportunities to be addressed to effect a paradigm shift in RA, where in the near future, proactive risk assessment focused on prevention of RA will become a public health strategy in much the same manner as cardiovascular disease is managed today.

Depression and Subsequent Risk for Incident Rheumatoid Arthritis Among Women

OBJECTIVE

To investigate the association of depression with subsequent risk of rheumatoid arthritis (RA) by serologic phenotype.

METHODS

We performed a cohort study using pooled data from the Nurses' Health Study (NHS; 1992-2014) and the NHSII (1993-2015). Depression was defined according to the following composite definition: diagnosis by clinician, regular antidepressant use, or a 5-question Mental Health Inventory score of <60 using time-updated questionnaires during follow-up. Incident RA cases met research criteria by medical record review. Information on covariates, including smoking, diet, and body mass index, was obtained using questionnaires. Cox regression estimated hazard ratios (HRs) and 95% confidence intervals (95% CIs) for RA risk (overall and by serologic phenotype) according to depression status and adjusted for potential confounders. All analyses included a time separation between assessments of depression and the window for RA risk of at least 4 years to lower the possibility that depressive symptoms due to early RA prior to diagnosis explained any associations.

RESULTS

Among 195,358 women, we identified 858 cases of incident RA (65% seropositive) over 3,087,556 person-years (median 17.9 years per participant). Compared to women without depression, those with depression had multivariable HRs as follows: 1.28 (95% CI 1.10-1.48) for all RA; 1.12 (95% CI 0.93-1.35) for seropositive RA; and 1.63 (95% CI 1.27-2.09) for seronegative RA. When analyzing components of the composite depression exposure variable, regular antidepressant use was not associated with subsequent seropositive RA (HR 1.21 [95% CI 0.97-1.49]) and was associated with seronegative RA (HR 1.75 [95% CI 1.32-2.32]).

CONCLUSION

Indicators of depression, specifically antidepressant use, were associated with subsequent increased risk for seronegative RA, and this finding was not explained by measured lifestyle factors prior to clinical presentation.

Lifestyle factors associated with incidence of rheumatoid arthritis in US adults: analysis of National Health and Nutrition Examination Survey database and meta-analysis

OBJECTIVE

To quantify rheumatoid arthritis (RA) cases attributable to selected non-genetic risk factors.

DESIGN

National Health and Nutrition Examination Survey (NHANES) and meta-analysis.

PARTICIPANTS

US adults.

DATA SOURCES

The prevalence of exposure was obtained from NHANES. Weighted analysis was performed to account for the complex sampling design in NHANES. PubMed and Web of Science up to 31 March 2019 were searched to identify epidemiological studies reported the association between non-genetic risk factors and RA in US adults. Relative risk (RR) value and the corresponding CI were pooled by meta-analysis to evaluate the associations between modifiable risk factors and RA. Population attributable fraction (PAF) was calculated based on the prevalence and RR data.

RESULTS

The weighted percentages of former smokers, current smokers and overweight or obese people were 24.84%, 23.93% and 63.97%, and the average alcohol consumption was 51.34 g/week. In the meta-analysis, we found that former smokers (RR 1.22, 95% CI 1.10 to 1.36) and current smokers (RR 1.47, 95% CI 1.29 to 1.68) had higher risks of RA. Overweight and obese individuals had 1.27-fold (95% CI 1.09 to 1.48) increased risk of RA. Each per 50 g/week increment of alcohol consumption was associated with 8% (95% CI 0% to 16%) reduction in the risk of RA. Therefore, PAF value of smoking was 14.00% (95% CI 8.13% to 23.33%). Excess body mass index (BMI) was found to account for 14.73% (95% CI 5.45% to 23.50%) of RA incidence. The fraction of RA risk attributed by low alcohol intake was 8.21% (95% CI 0.31% to 16.39%). Collectively, we found that 32.69% (95% CI 13.41% to 50.96%) of RA cases were attributable to smoking, overweight or obesity and low alcohol drinking.

CONCLUSION

Nearly 33% of RA incidence was attributed to smoking, excess BMI and low alcohol drinking in USA. Our findings could provide a basis for developing guidelines of RA prevention and control in USA.

Inhalants other than personal cigarette smoking and risk for developing rheumatoid arthritis

PURPOSE OF REVIEW

The current review summarizes the current evidence on inhalants other than personal cigarette smoking and risk for developing rheumatoid arthritis (RA).

RECENT FINDINGS

Personal cigarette smoking has been implicated as an environmental risk factor for seropositive RA, perhaps by inducing autoimmunity at pulmonary mucosa. Since many patients with RA are nonsmokers, other inhalants are being investigated as potential RA risk factors. Recent case-control and cohort studies have investigated passive cigarette smoking, air pollution, inhalant-related occupations, silica, pesticides, household environment, and allergic inhalants as inhalant exposures for RA risk. Inhalant-related occupations and silica inhalants have the most consistent evidence for associations with increased RA risk. However, most studies relied on retrospective designs and had limited ability to adjust for personal cigarette smoking or investigate associations among nonsmokers.

SUMMARY

Several inhalants other than personal cigarette smoking may be associated with increased risk for developing RA. These results support the hypothesis that inhalants, pulmonary mucosal inflammation, and RA pathogenesis may be linked. Future studies are needed to firmly establish the independence of these findings from personal cigarette smoking and to determine the specific inhalants and biologic mechanisms related to RA pathogenesis.

Decreased Risk of Parkinson's Disease After Rheumatoid Arthritis Diagnosis: A Nested Case-Control Study with Matched Cases and Controls

BACKGROUND

Rheumatoid arthritis (RA) and the genetic risk landscape of autoimmune disorders and Parkinson's disease (PD) overlap. Additionally, anti-inflammatory medications used to treat RA might influence PD risk.

OBJECTIVE

To use a population-based approach to determine if there is an association between pre-occurring rheumatoid arthritis (RA) and later-life risk of PD.

METHODS

The study population was 3.6 million residents of Sweden, who were alive during part or all of the follow-up period; 1997-2016. We obtained diagnoses from the national patient registry and identified 30,032 PD patients, 8,256 of whom each was matched to ten controls based on birth year, sex, birth location, and time of follow-up. We determined the risk reduction for PD in individuals previously diagnosed with RA. We also determined if the time (in relation to the index year) of the RA diagnosis influenced PD risk and repeated the analysis in a sex-stratified setting.

RESULTS

Individuals with a previous diagnosis of RA had a decreased risk of later developing PD by 30-50% compared to individuals without an RA diagnosis. This relationship was strongest in our conservative analysis, where the first PD diagnosis occurred close to the earliest PD symptoms (odds ratio 0.47 (CI 95% 0.28-0.75, p = 0.0006); with the greatest risk reduction in females (odds ratio 0.40 (CI 95% 0,19-0.76, p = 0.002).

DISCUSSION

Our findings provide evidence that individuals diagnosed with RA have a significantly lower risk of developing PD than the general population. Our data should be considered when developing or repurposing therapies aimed at modifying the course of PD.

Beverages in Rheumatoid Arthritis: What to Prefer or to Avoid

Background: The role of nutrition in the pathogenesis of rheumatic diseases, including rheumatoid arthritis (RA), has gained increasing attention in recent years. A growing number of studies have focussed on the diverse nutritional contents of beverages, and their possible role in the development and progression of RA. Main body: We aimed to summarise the current knowledge on the role of a range of beverages in the context of RA. Beverages have a key role within the mosaic of autoimmunity in RA and potential to alter the microbiome, leading to downstream effects on inflammatory pathways. The molecular contents of beverages, including coffee, tea, and wine, have similarly been found to interfere with immune signalling pathways, some beneficial for disease progression and others less so. Finally, we consider beverages in the context of wider dietary patterns, and how this growing body of evidence may be harnessed by the multidisciplinary team in patient management. Conclusions: While there is increasing work focussing on the role of beverages in RA, integration of discussions around diet and lifestyle in our management of patients remains sparse. Nutrition in RA remains a controversial topic, but future studies, especially on the role of beverages, are likely to shed further light on this in coming years.

Environment and Lifestyle: Their Influence on the Risk of RA

Background: Rheumatoid arthritis (RA) is a complex disease in which environmental agents are thought to interact with genetic factors that lead to triggering of autoimmunity. Methods: We reviewed environmental, hormonal, and dietary factors that have been suggested to be associated with the risk of RA. Results: Smoking is the most robust factor associated with the risk of RA, with a clear gene–environment interaction. Among other inhalants, silica may increase the risk of RA in men. There is less evidence for pesticides, pollution, and other occupational inhalants. Regarding female hormonal exposures, there is some epidemiological evidence, although not consistent in the literature, to suggest a link between hormonal factors and the risk of RA. Regarding dietary factors, available evidence is conflicting. A high consumption of coffee seems to be associated with an increased risk of RA, whereas a moderate consumption of alcohol is inversely associated with the risk of RA, and there is less evidence regarding other food groups. Dietary pattern analyses (Mediterranean diet, the inflammatory potential of the diet, or diet quality) suggested a potential benefit of dietary modifications for individuals at high risk of RA. Conclusion: To date, smoking and silica exposure have been reproducibly demonstrated to trigger the emergence of RA. However, many other environmental factors have been studied, mostly with a case-control design. Results were conflicting and studies rarely considered potential gene–environment interactions. There is a need for large scale prospective studies and studies in predisposed individuals to better understand and prevent the disease and its course.

Rheumatoid arthritis-associated interstitial lung disease: Current update on prevalence, risk factors, and pharmacologic treatment

Purpose of review

Rheumatoid arthritis-associated interstitial lung disease (RA-ILD) is one of the most serious extra-articular RA manifestations. RA-ILD is associated with worse physical function, lower quality of life, and increased mortality. RA-ILD is comprised of heterogeneous subtypes characterized by inflammation and fibrosis. Diagnosis can be difficult since the presentation of RA-ILD is characterized by non-specific symptoms and imaging findings. Management of RA-ILD is also challenging due to difficulty in precisely measuring pulmonary disease activity and response to treatment in patients who may also have articular inflammation. We provide a current overview of RA-ILD focusing on prevalence, risk factors, and treatment.

Recent findings

Research interest in RA-ILD has increased in recent years. Some studies suggest that RA-ILD prevalence may be increasing; this may be due to underlying biologic drivers or increases in imaging and recognition. Novel RA-ILD risk factors include the MUC5B promotor variant, articular disease activity, autoantibodies, and biomarkers of damaged pulmonary parenchyma. Treatment should focus on controlling RA disease activity, which emerging data suggest may reduce RA-ILD risk. Immunomodulatory and antifibrotic drugs may also treat RA-ILD.

Summary

RA-ILD is an underrecognized and serious manifestation of RA, but important progress is being made in identifying risk factors and treatment.

The impact of lifestyle behaviours, physical activity and smoking on morbidity and mortality in patients with rheumatoid arthritis

Rheumatoid arthritis (RA) is associated with pain, disability and increased risk of developing comorbidities and premature mortality. While these poor outcomes have improved in line with advances in the treatment of RA, they still persist to some degree today. Physical activity and smoking are two areas of patients' lives where changes may have a substantial impact on the poor outcomes associated with RA. Physical activity in RA has been well studied, with many randomised trials indicating the benefits of physical activity on pain and disability. A number of observational studies have assessed the impact of smoking on RA, also indicating the benefits of quitting smoking on RA-related outcomes, but with less consistent findings, potentially due to epidemiological challenges (e.g. collider bias, recall bias). There are also a number of barriers preventing patients making these positive lifestyle changes, such as lack of time and motivation, lack of knowledge and advice, as well as disease-specific barriers, such as pain and fatigue.

Precision medicine in the care of rheumatoid arthritis: Focus on prediction and prevention of future clinically-apparent disease

There is an emerging understanding that an individual's risk for future rheumatoid arthritis (RA) can be determined using a combination of factors while they are still in a state where clinically-apparent inflammatory arthritis (IA) is not yet present. Indeed, this concept has underpinned several completed and ongoing prevention trials in RA. Importantly, risk factors can be divided into modifiable (e.g. smoking, exercise, dental care and diet) and non-modifiable factors (e.g. genetics, sex, age). In addition, there are now several biomarkers including autoantibodies, inflammatory markers and imaging techniques that are highly predictive of future clinically-apparent IA/RA. Although none of the prevention studies have yet provided major breakthroughs, several of them have provided valuable insights that can help to improve the design of future clinical trials and enable RA prevention. In aggregate, these findings suggest that the most accurate disease prediction models will require the combination of demographic and clinical information, biomarkers and potentially medical imaging data to identify individuals for intervention. This review summarizes some of the key aspects around precision medicine in RA with special focus on disease prediction and prevention.

Predictors of Smoking Cessation in Patients With Rheumatoid Arthritis in Two Cohorts: Most Predictive Health Care Factors

OBJECTIVE

Recognizing smoking as a risk factor for rheumatoid arthritis (RA) severity, the present study was undertaken to evaluate patient- and health care-level predictors of smoking cessation in patients with RA to guide implementation of smoking cessation interventions.

METHODS

Electronic health record data from 2 health systems were abstracted for patients with at least 2 International Classification of Disease diagnosis codes for RA between 2005 and 2016. Patients missing smoking statuses or with <6 months of follow-up were excluded. Multivariable logistic regression was used to determine predictors of smoking cessation.

RESULTS

Among 3,577 patients with RA, 507 smoked at baseline, and 29% quit over a median of 4.75 years. Black male patients, ages 40-59 years and enrolled in Medicaid, were significantly more likely to be baseline smokers; however, none of these factors predicted cessation. Instead, patients new to rheumatology care were 60% more likely to quit (adjusted odds ratio [OR_adj ] 1.60 [95% confidence interval (95% CI) 1.02-2.50]), and patients in the rural community health system were 66% more likely to quit (OR_adj 1.66 [95% CI 1.03-2.69]). Seropositive patients were 43% less likely to quit smoking (OR_adj 0.57 [95% CI 0.35-0.91]).

CONCLUSION

Health care factors, including health system and being new to rheumatology care, were more predictive of smoking cessation in patients with RA than patient sociodemographic factors, suggesting an important role for health system cessation efforts for patients with RA. Seropositive patients were less likely to quit and may particularly benefit from cessation support. Emphasizing smoking cessation with new or seropositive RA patients and leveraging health system interventions could improve smoking cessation and outcomes in RA.