Treatment strategies for a rheumatoid arthritis patient with interstitial lung disease

N-Acetyl-L-cysteine in human rheumatoid arthritis and its effects on nitric oxide (NO) and malondialdehyde (MDA): analytical and clinical considerations

N-Acetyl-L-cysteine (NAC) is an endogenous cysteine metabolite. The drug is widely used in chronic obstructive pulmonary disease (COPD) and as antidote in acetaminophen (paracetamol) intoxication. Currently, the utility of NAC is investigated in rheumatoid arthritis (RA), which is generally considered associated with inflammation and oxidative stress. Besides clinical laboratory parameters, the effects of NAC are evaluated by measuring in plasma or serum nitrite, nitrate or their sum (NOx) as measures of nitric oxide (NO) synthesis. Malondialdehyde (MDA) and relatives such as 4-hydroxy-nonenal and 15(S)-8-iso-prostaglandin F_2α serve as measures of oxidative stress, notably lipid peroxidation. In this work, we review recent clinico-pharmacological studies on NAC in rheumatoid arthritis. We discuss analytical, pre-analytical and clinical issues and their potential impact on the studies outcome. Major issues include analytical inaccuracy due to interfering endogenous substances and artefactual formation of MDA and relatives during storage in long-term studies. Differences in the placebo and NAC groups at baseline with respect to these biomarkers are also a serious concern. Modern applied sciences are based on data generated using commercially available instrumental physico-chemical and immunological technologies and assays. The publication process of scientific work rarely undergoes rigorous peer review of the analytical approaches used in the study in terms of accuracy/trueness. There is pressing need of considering previously reported reference concentration ranges and intervals as well as specific critical issues such as artefactual formation of particular biomarkers during sample storage. The latter especially applies to surrogate biomarkers of oxidative stress, notably MDA and relatives. Reported data on NO, MDA and clinical parameters, including C-reactive protein, interleukins and tumour necrosis factor α, are contradictory in the literature. Furthermore, reported studies do not allow any valid conclusion about utility of NAC in RA. Administration of NAC patients with rheumatoid arthritis is not recommended in current European and American guidelines.

Novel Biomarkers, Diagnostic and Therapeutic Approach in Rheumatoid Arthritis Interstitial Lung Disease-A Narrative Review

Rheumatoid arthritis (RA) is considered a systemic inflammatory disease marked by polyarthritis which affects the joints symmetrically, leading to progressive damage of the bone structure and eventually joint deformity. Lung involvement is the most prevalent extra-articular feature of RA, affecting 10-60% of patients with this disease. In this review, we aim to discuss the patterns of RA interstitial lung disease (ILD), the molecular mechanisms involved in the pathogenesis of ILD in RA, and also the therapeutic challenges in this particular extra-articular manifestation. The pathophysiology of RA-ILD has been linked to biomarkers such as anti-citrullinated protein antibodies (ACPAs), MUC5B mutation, Krebs von den Lungen 6 (KL-6), and other environmental factors such as smoking. Patients at the highest risk for RA-ILD and those most likely to advance will be identified using biomarkers. The hope is that finding biomarkers with good performance characteristics would help researchers better understand the pathophysiology of RA-ILD and, in turn, lead to the development of tailored therapeutics for this severe RA manifestation.

Consensus recommendations on managing the selected comorbidities including cardiovascular disease, osteoporosis, and interstitial lung disease in rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA)-related comorbidities, including cardiovascular disease (CVD), osteoporosis (OP), and interstitial lung disease (ILD), are sub-optimally managed. RA-related comorbidities affect disease control and lead to impairment in quality of life. We aimed to develop consensus recommendations for managing RA-related comorbidities.

METHODS

The consensus statements were formulated based on emerging evidence during a face-to-face meeting of Taiwan rheumatology experts and modified through three-round Delphi exercises. The quality of evidence and strength of recommendation of each statement were graded after a literature review, followed by voting for agreement. Through a review of English-language literature, we focused on the existing evidence of management of RA-related comorbidities.

RESULTS

Based on experts' consensus, eleven recommendations were developed. CVD risk should be assessed in patients at RA diagnosis, once every 5 years, and at changes in DMARDs therapy. Considering the detrimental effects of nonsteroidal anti-inflammatory drugs (NSAIDs) and corticosteroids on CVD risks, we recommend using the lowest possible dose of corticosteroids and prescribing NSAIDs cautiously. The OP/fragility fracture risk assessment includes dual-energy X-ray absorptiometry and fracture risk assessment (FRAX) in RA. The FRAX-based approach with intervention threshold is a useful strategy for managing OP. RA-ILD assessment includes risk factors, pulmonary function tests, HRCT imaging and a multidisciplinary decision approach to determine RA-ILD severity. A treat-to-target strategy would limit RA-related comorbidities.

CONCLUSIONS

These consensus statements emphasize that adequate control of disease activity and the risk factors are needed for managing RA-related comorbidities, and may provide useful recommendations for rheumatologists on managing RA-related comorbidities.

Rheumatoid arthritis related interstitial lung disease - improving outcomes over 25 years: a large multicentre UK study

OBJECTIVE

This study explores whether the prognosis of interstitial lung disease in rheumatoid arthritis (RA-ILD) has improved over time and assesses the potential influence of drug therapy in a large multicentre UK network.

METHODS

We analysed data from 18 UK centres on patients meeting criteria for both RA and ILD diagnosed over a 25-year period. Data included age, disease duration, outcome and cause of death. We compared all cause and respiratory mortality between RA controls and RA-ILD patients, assessing the influence of specific drugs on mortality in four quartiles based on year of diagnosis.

RESULTS

A total of 290 RA-ILD patients were identified. All cause (respiratory) mortality was increased at 30% (18%) compared with controls 21% (7%) (P =0.02). Overall, prognosis improved over quartiles with median age at death rising from 63 years to 78 years (P =0.01). No effect on mortality was detected as a result of DMARD use in RA-ILD. Relative risk (RR) of death from any cause was increased among patients who had received anti-TNF therapy [2.09 (1.1-4.0)] P =0.03, while RR was lower in those treated with rituximab [0.52(0.1-2.1)] or mycophenolate [0.65 (0.2-2.0)]. Patients receiving rituximab as their first biologic had longer three (92%), five (82%) and seven year (80%) survival than those whose first biologic was an anti-TNF agent (82%, 76% and 64%, respectively) (P =0.037).

DISCUSSION

This large retrospective multicentre study demonstrates survival of patients with RA-ILD has improved. This may relate to the increasing use of specific immunosuppressive and biologic agents.

Beyond the joints, the extra-articular manifestations in rheumatoid arthritis

Rheumatoid arthritis (RA) is an inflammatory disease typically affecting the joints, but the systemic inflammatory process may involve other tissues and organs. Many extra-articular manifestations are recognized, which are related to worse long outcomes. Rheumatoid nodules are the most common extra-articular feature, found in about 30% of patients. Secondary Sjögren's syndrome and pulmonary manifestations are observed in almost 10% of patients, also in the early disease. Active RA with high disease activity has been associated with an increased risk of such features. Male gender, smoking habit, severe joint disease, worse function, high pro-inflammatory markers levels, high titer of rheumatoid factor, and HLA-related shared epitope have been reported as clinical predictors of occurrence of these rheumatoid complications. In addition, there is a little evidence deriving from randomized controlled trials in this field, thus the therapeutic strategy is mainly empiric and based on small case series and retrospective studies. However, considering that these extra-articular manifestations are usually related to the more active and severe RA, an aggressive therapeutic strategy is usually employed in view of the poor outcomes of these patients. The extra-articular features of RA remain, despite the improvement of joint damage, a major diagnostic and therapeutic challenge, since these are associated with a poor prognosis and need to be early recognized and promptly managed.

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.

Rheumatoid arthritis-associated interstitial lung disease: an overview of epidemiology, pathogenesis and management

Interstitial lung disease (ILD) accounts for the major cause of morbidity and mortality in rheumatoid arthritis (RA). However, little is known of the pathogenesis, diagnosis and treatment of RA-associated ILD. In this review, we describe our present understanding and ongoing research in RA-ILD. Its aetiology does appear to associate with anti-cyclic citrullinated peptide antibodies, MUC5B mutation and smoking. Another focus of this article is on recent diagnostic methods in RA-ILD. Compared with other methods, high-resolution computed tomography (HRCT) imaging is a main method for the evaluation of ILD in RA patients. Pulmonary function is better suited for assessing progression. An important topic relates to therapeutic intervention. Disease-modifying anti-rheumatic drugs (DMARDs) in RA lack strong evidence in the onset or worsening of ILD. The available literature support that methotrexate, leflunomide, abatacept and rituximab play beneficial roles in the prevention and treatment of RA-ILD.

Rheumatoid Arthritis-Associated Interstitial Lung Disease: Current Concepts

PURPOSE OF REVIEW

Among the many extra-articular complications of rheumatoid arthritis (RA), interstitial lung disease (ILD) contributes significantly to morbidity and mortality. Prevalence estimates for RA-ILD vary widely depending on the specific clinical, radiographic, and functional criteria used to establish the diagnosis. A key unresolved issue is whether early, subclinical forms of RA-ILD represent a precursor to end stage, fibrotic lung disease. Based on uncertainties surrounding the natural history of RA-ILD, incomplete understanding of underlying disease pathogenesis, and lack of controlled clinical trials, evidence-based therapeutic strategies remain largely undefined.

RECENT FINDINGS

Correlative clinico-epidemiological studies have identified key risk factors for disease progression. Complementing these findings, the identification of specific molecular and serological markers of RA-ILD has improved our understanding of disease pathogenesis and established the foundation for predictive biomarker profiling. Experience from case series and cohort studies suggests that newer biological agents such as rituximab may be viable treatment options. RA-ILD continues to have a major impact on "disease intrinsic" morbidity and mortality. Increased understanding of disease pathogenesis and the natural history of subclinical RA-ILD will promote the development of more refined therapeutic strategies.

Recent advances in the pathogenesis, prediction, and management of rheumatoid arthritis-associated interstitial lung disease

PURPOSE OF REVIEW

To provide an overview of recently published articles covering interstitial lung disease associated with rheumatoid arthritis (RA-ILD).

RECENT FINDINGS

Over the past year, many studies replicated previous findings in more diverse and occasionally larger populations internationally. Specifically, the association among cigarette smoking, high rheumatoid factor titer, elevated anticitrullinated protein antibody (ACPA) levels, and RA-ILD was strengthened. Clinical characteristics, autoantibodies, and biomarkers to aid in RA-ILD development, progression, and mortality prediction were explored. Finally, direct and indirect treatment effects were highlighted.

SUMMARY

The ability to identify risk factors for preclinical RA-ILD has been enhanced, but the proper management strategy for these patients is yet to be defined. ACPAs and cigarette smoking are highly associated with RA-ILD, but the mechanistic relationship between lung injury and autoantibody generation remains unknown. There is conflicting evidence regarding the significance of a usual interstitial pneumonia (UIP) versus non-UIP pattern on high-resolution computed tomography. The use of biologic agents in patients with rheumatoid arthritis does not appear to increase the risk of incident ILD or RA-ILD exacerbation. Randomized prospective studies of specific therapy for RA-ILD are still lacking.

Lung involvement in inflammatory rheumatic diseases

This chapter describes the involvement of the lung in systemic inflammatory joint disease (IJD) with a particular focus on rheumatoid arthritis, although the topics of pulmonary involvement in ankylosing spondylitis and psoriatic arthritis are also addressed. Interstitial lung disease is the most lethal pulmonary complication of IJD and the chapter describes recent advances in both our understanding of this complication and the therapeutic options that offer real hope for improved outcomes. Although less well recognised, airways disease is just as common and its association with IJD is described in some detail, with a section devoted to the recent surge in interest in bronchiectasis. Acute pulmonary infection is common in IJD and its management is reviewed in some detail. Although pleural disease is less common than it once was, its treatment is explored. We conclude by reviewing the relationship between the drug therapies employed in IJD and their effects on the lung.

Activation of mTOR (mechanistic target of rapamycin) in rheumatic diseases

Mechanistic target of rapamycin (mTOR, also known as mammalian target of rapamycin) is a ubiquitous serine/threonine kinase that regulates cell growth, proliferation and survival. These effects are cell-type-specific, and are elicited in response to stimulation by growth factors, hormones and cytokines, as well as to internal and external metabolic cues. Rapamycin was initially developed as an inhibitor of T-cell proliferation and allograft rejection in the organ transplant setting. Subsequently, its molecular target (mTOR) was identified as a component of two interacting complexes, mTORC1 and mTORC2, that regulate T-cell lineage specification and macrophage differentiation. mTORC1 drives the proinflammatory expansion of T helper (TH) type 1, TH17, and CD4(-)CD8(-) (double-negative, DN) T cells. Both mTORC1 and mTORC2 inhibit the development of CD4(+)CD25(+)FoxP3(+) T regulatory (TREG) cells and, indirectly, mTORC2 favours the expansion of T follicular helper (TFH) cells which, similarly to DN T cells, promote B-cell activation and autoantibody production. In contrast to this proinflammatory effect of mTORC2, mTORC1 favours, to some extent, an anti-inflammatory macrophage polarization that is protective against infections and tissue inflammation. Outside the immune system, mTORC1 controls fibroblast proliferation and chondrocyte survival, with implications for tissue fibrosis and osteoarthritis, respectively. Rapamycin (which primarily inhibits mTORC1), ATP-competitive, dual mTORC1/mTORC2 inhibitors and upstream regulators of the mTOR pathway are being developed to treat autoimmune, hyperproliferative and degenerative diseases. In this regard, mTOR blockade promises to increase life expectancy through treatment and prevention of rheumatic diseases.

Treatment of rheumatoid arthritis-associated interstitial lung disease: a perspective review

Rheumatoid arthritis (RA) is a systemic autoimmune disease affecting 0.5-1% of the worldwide population. Whilst predominantly causing chronic pain and inflammation in synovial joints, it is also associated with significant extra-articular manifestations in a large proportion of patients. Among the various pulmonary manifestations, interstitial lung disease (ILD), a progressive fibrotic disease of the lung parenchyma, is the commonest and most important, contributing significantly to increased morbidity and mortality. The most frequent patterns of RA-associated ILD (RA-ILD) are usual interstitial pneumonia and nonspecific interstitial pneumonia. New insights during the past several years have highlighted the epidemiological impact of RA-ILD and have begun to identify factors contributing to its pathogenesis. Risk factors include smoking, male sex, human leukocyte antigen haplotype, rheumatoid factor and anticyclic citrullinated protein antibodies (ACPAs). Combined with clinical information, chest examination and pulmonary function testing, high-resolution computed tomography of the chest forms the basis of investigation and allows assessment of subtype and disease extent. The management of RA-ILD is a challenge. Several therapeutic agents have been suggested in the literature but as yet no large randomized controlled trials have been undertaken to guide clinical management. Therapy is further complicated by commonly prescribed drugs of proven articular benefit such as methotrexate, leflunomide (LEF) and anti-tumour necrosis factor α agents having been implicated in both ex novo occurrence and acceleration of existing ILD. Agents that offer promise include immunomodulators such as mycophenolate and rituximab as well as newly studied antifibrotic agents. In this review, we discuss the current literature to evaluate recommendations for the management of RA-ILD and discuss key gaps in our knowledge of this important disease.

Collagen vascular disease-associated interstitial lung disease

Interstitial lung disease (ILD) is an important manifestation of collagen vascular diseases. It is a common feature of scleroderma, and also occurs in dermatomyositis and polymyositis, mixed connective tissue disease, Sjogren’s syndrome, rheumatoid arthritis, systemic lupus erythematosus, and Antineutrophil cytoplasmic antibody-associated vasculitis. When present, it is associated with increased morbidity and mortality, thus making early diagnosis important. In fact, in many patients, ILD may be the first manifestation of a collagen vascular disease. The most common symptoms are cough and dyspnea. The diagnosis is made based on pulmonary function tests showing restrictive lung disease and impaired oxygen diffusion and chest imaging showing ground glass infiltrates, interstitial thickening, and/or fibrosis. The most common histologic finding on lung biopsy is non-specific interstitial pneumonia, though organizing pneumonia and usual interstitial pneumonia may also be seen. Treatment is focused on addressing the underlying collagen vascular disease with immunosuppression, either with corticosteroids or a steroid-sparing agent such as cyclophosphamide, azathioprine, or mycophenolate, although the optimal agent and duration of therapy is not known. There are few clinical trials to guide therapy that focus specifically on the progression of ILD. The exception is in the case of scleroderma-associated ILD, where cyclophosphamide has been shown to be effective.

Interstitial lung disease in patients with rheumatoid arthritis: spontaneous and drug induced

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease characterized by the destruction of articular joint structures. RA is a systemic condition that often affects multiple organs, including the heart, lungs, and kidneys. Pulmonary complications of RA are relatively common and include pleural effusion, rheumatoid nodules, bronchiectasis, obliterative bronchiolitis, and opportunistic infections. Interstitial lung disease (ILD) is a common occurrence in patients with RA, and can range in severity from an asymptomatic incidental finding to a rapidly progressing life-threatening event. Usual interstitial pneumonia and non-specific interstitial pneumonia are the two most common patterns, though others have been reported. Various disease-modifying anti-rheumatic drugs-in particular, methotrexate and the tumor necrosis factor-alpha inhibitors-have been associated with RA-ILD in numerous case reports and case series, though it is often difficult to distinguish association from causality. Treatment for RA-ILD typically involves the use of high-dose corticosteroids, often in conjunction with alternative immunosuppressant agents such as azathioprine or mycophenolate mofetil, and outcomes vary widely depending on the initial pattern of lung disease. Additional research into the mechanisms driving RA-ILD is needed to guide future therapy.

Anti-citrullinated heat shock protein 90 antibodies identified in bronchoalveolar lavage fluid are a marker of lung-specific immune responses

Previous work has demonstrated a correlation between serum anti-citrullinated HSP90 antibodies and rheumatoid arthritis-associated interstitial lung disease (RA-ILD). To further investigate this potential pathogenic relationship, we used ELISA-based techniques to assess anti-citrullinated HSP90 antibody profiles in bronchoalveolar lavage fluid (BALF) of patients with different stages of RA-ILD. 9/21 RA-derived BALF specimens demonstrated IgG and/or IgA antibodies targeting citrullinated HSP90 proteins/peptides, highlighting disease specific responses (with a predilection for RA-ILD) that did not occur in IPF patients (0/5) or healthy control subjects (0/5). Comparison of antibody profiles between BALF and matching serum specimens revealed various recognition patterns favoring predominant production of anti-citrullinated HSP90 antibodies within the lung microenvironment-further supporting the connection between this antibody specificity and parenchymal lung disease. Equally important, qualitative as well as quantitative differences in anti-citrullinated HSP90 profiles between BALF and serum indicate that the lung plays a direct role in shaping the immune repertoire of RA/RA-ILD.

Rheumatoid Arthritis (RA) associated interstitial lung disease (ILD)

Rheumatoid Arthritis (RA) is the most common Connective Tissue Disease (CTD) and represents an increasing burden on global health resources. Interstitial lung disease (ILD) has been recognised as a complication of RA but its potential for mortality and morbidity has arguably been under appreciated for decades. New studies have underscored a significant lifetime risk of ILD development in RA. Contemporary work has identified an increased risk of mortality associated with the Usual Interstitial Pneumonia (UIP) pattern which shares similarity with the most devastating of the interstitial pulmonary diseases, namely Idiopathic Pulmonary Fibrosis (IPF). In this paper, we discuss recent studies highlighting the associated increase in mortality in RA-UIP. We explore associations between radiological and histopathological features of RA-ILD and the prognostic implications of same. We emphasise the need for translational research in this area given the growing burden of RA-ILD. We highlight the importance of the respiratory physician as a key stakeholder in the multidisciplinary management of this disorder. RA-ILD focused research offers the opportunity to identify early asymptomatic disease and define the natural history of this extra articular manifestation. This may provide a unique opportunity to define key regulatory fibrotic events driving progressive disease. We also discuss some of the more challenging and novel aspects of therapy for RA-ILD.

The multifaceted aspects of interstitial lung disease in rheumatoid arthritis

Interstitial lung disease (ILD) is a relevant extra-articular manifestation of rheumatoid arthritis (RA) that may occur either in early stages or as a complication of long-standing disease. RA related ILD (RA-ILD) significantly influences the quoad vitam prognosis of these patients. Several histopathological patterns of RA-ILD have been described: usual interstitial pneumonia (UIP) is the most frequent one, followed by nonspecific interstitial pneumonia (NSIP); other patterns are less commonly observed. Several factors have been associated with an increased risk of developing RA-ILD. The genetic background plays a fundamental but not sufficient role; smoking is an independent predictor of ILD, and a correlation with the presence of rheumatoid factor and anti-cyclic citrullinated peptide antibodies has also been reported. Moreover, both exnovo occurrence and progression of ILD have been related to drug therapies that are commonly prescribed in RA, such as methotrexate, leflunomide, anti-TNF alpha agents, and rituximab. A greater understanding of the disease process is necessary in order to improve the therapeutic approach to ILD and RA itself and to reduce the burden of this severe extra-articular manifestation.

Lung involvement in connective tissue diseases: a comprehensive review and a focus on rheumatoid arthritis

The lungs are frequently involved in Connective Tissue Diseases (CTDs). Interstitial lung disease (ILD) is one of the most common pleuropulmonary manifestations that affects prognosis significantly. In practice, rheumatologists and other physicians tend to underestimate the impact of CTD-ILDs and diagnose respiratory impairment when it has reached an irreversible fibrotic stage. Early investigation, through clinical evidence, imaging and - in certain cases - lung biopsy, is therefore warranted in order to detect a possible ILD at a reversible initial inflammatory stage. In this review, we focus on lung injury during CTDs, with particular attention to ILDs, and examine their prevalence, clinical manifestations and histological patterns, as well as therapeutic approaches and known complications till date. Although several therapeutic agents have been approved, the best treatment is still not certain and additional trials are required, which demand more knowledge of pulmonary involvement in CTDs. Our central aim is therefore to document the impact that lung damage has on CTDs. We will mainly focus on Rheumatoid Arthritis (RA), which - unlike other rheumatic disorders - resembles Idiopathic Pulmonary Fibrosis (IPF) in numerous aspects.

Interstitial lung disease in the connective tissue diseases

The connective tissue diseases (CTDs) are inflammatory, immune-mediated disorders in which interstitial lung disease (ILD) is common and clinically important. Interstitial lung disease may be the first manifestation of a CTD in a previously healthy patient. CTD-associated ILD frequently presents with the gradual onset of cough and dyspnea, although rarely may present with fulminant respiratory failure. Infection and drug reaction should always be ruled out. A diagnosis of idiopathic ILD should never be made without a careful search for subtle evidence of underlying CTD. Treatment of CTD-ILD typically includes corticosteroids and immunosuppressive agents.

Co-morbidities in established rheumatoid arthritis

Co-morbid conditions are common in patients with rheumatoid arthritis (RA). Although the presence of co-morbid conditions can be assessed using standardised indexes such as the Charlson index, most clinicians prefer to simply record their presence. Some co-morbidities are causally associated with RA and many others are related to its treatment. Irrespective of their underlying pathogenesis, co-morbidities increase disability and shorten life expectancy, thereby increasing both the impact and mortality of RA. Cardiac co-morbidities are the most crucial, because of their frequency and their negative impacts on health. Treatment of cardiac risk factors and reducing RA inflammation are both critical in reducing cardiac co-morbidities. Gastrointestinal and chest co-morbidities are both also common. They are often associated with drug treatment, including non-steroidal anti-inflammatory drug and disease-modifying drugs. Osteoporosis and its associated fracture risk are equally important and are often linked to long-term glucocorticoid treatment. The range of co-morbidities associated with RA is increasing with the recognition of new problems such as periodontal disease. Optimal medical care for RA should include an assessment of associated co-morbidities and their appropriate management. This includes risk factor modification where possible. This approach is essential to improve quality of life and reduce RA mortality. An area of genuine concern is the impact of treatment on co-morbidities. A substantial proportion is iatrogenic. As immunosuppression with conventional disease-modifying drugs and biologics has many associated risks, ranging from liver disease to chest and other infections, it is essential to balance the risks of co-morbidities against the anticipated benefits of treatment.

Pulmonary manifestations of rheumatoid arthritis

Pulmonary disease is a major source of morbidity and mortality in rheumatoid arthritis, manifesting most commonly as interstitial lung disease, airways disease, rheumatoid nodules, and pleural effusions. The diagnostic assessment of respiratory abnormalities is complicated by underlying risk for infection, the use of drugs with known pulmonary toxicity, and the frequency of lung disease related to rheumatoid arthritis itself. Evaluation and management of rheumatoid arthritis-associated pulmonary disease frequently necessitates a multidisciplinary approach.

Bronchus-associated lymphoid tissue (BALT) structure and function

Bronchus-associated lymphoid tissue (BALT) is a constitutive mucosal lymphoid tissue adjacent to major airways in some mammalian species, including rats and rabbits, but not humans or mice. A related tissue, inducible BALT (iBALT), is an ectopic lymphoid tissue that is formed upon inflammation or infection in both mice and humans and can be found throughout the lung. Both BALT and iBALT acquire antigens from the airways and initiate local immune responses and maintain memory cells in the lungs. Here, we discuss the development and function of BALT and iBALT in the context of pulmonary immunity to infectious agents, tumors, and allergens as well as autoimmunity and inflammatory diseases of the lung.

Advances in the medical treatment of rheumatoid arthritis

Over the past 2 decades, the treatment of rheumatoid arthritis (RA) has been revolutionized by advances in the understanding of its pathologic mechanisms and the development of drugs that target them. These newer medications have shown great promise at improving disease outcomes, but they come with notable side effects that can pose long-term treatment challenges and difficulties in the perioperative arena. In this article, the major manifestations of RA and the current medical options for management are discussed. Complications from treatment are then reviewed, and special consideration is given to perioperative medication recommendations.

Interstitial lung disease in rheumatoid arthritis

Rheumatoid arthritis (RA) is the most common systemic autoimmune disease in the United States, affecting 1% to 2% of the adult population. Although joints and synovium are the primary targets in this disorder, extra-articular manifestations involving the lungs can lead to significant morbidity and excess mortality. Among the various pulmonary complications that occur in RA, interstitial lung disease (ILD) is the most damaging, with effects ranging from subclinical inflammation/scarring to end-stage pulmonary fibrosis. New insights during the past several years have underscored the epidemiologic impact of clinically/functionally significant RA-associated ILD (RA-ILD) and have begun to identify factors contributing to the pathogenesis of this potentially devastating complication of RA. Despite these advancements, the complexity of RA-ILD and the lack of reliable predictors for disease progression highlight the need for improved biomarker development. Establishing such detailed molecular signatures will ultimately guide the application and timing of therapeutic agents that include immunomodulators as well as newly studied antifibrotic agents.

Respiratory symptoms and disease characteristics as predictors of pulmonary function abnormalities in patients with rheumatoid arthritis: an observational cohort study

INTRODUCTION

Lung involvement is a common extra-articular manifestation of rheumatoid arthritis (RA) that confers significant morbidity and mortality. The objective of the present study is to assess which respiratory symptoms and patient and disease characteristics are most highly associated with pulmonary function test (PFT) abnormalities in an RA patient cohort without clinical cardiovascular disease.

METHODS

A total of 159 individuals with RA and without clinically evident cardiovascular disease were evaluated. Respiratory symptoms were assessed with the Lung Tissue Research Consortium questionnaire and all patients underwent evaluation with PFTs. Demographic, lifestyle, RA disease and treatment characteristics were collected. Subclinical coronary artery disease was assessed by cardiac computed tomography. Multivariable regression analysis was used to identify pulmonary symptoms and nonpulmonary parameters associated with PFT abnormalities. Areas under the receiver operating characteristic curves (AUC) were calculated to evaluate the discrimination of these variables for identifying patients with PFT abnormalities.

RESULTS

Respiratory symptoms were reported by 42% of the patient population. Although only 6% carried a prior diagnosis of lung disease, PFT abnormalities were identified in 28% of the subjects. Symptoms combined with other patient and RA characteristics (body mass index, current smoking, anti-cyclic citrullinated peptide antibodies, and current prednisone use) performed satisfactorily in predicting the PFT abnormalities of obstruction (AUC=0.91, 95% confidence interval=0.78 to 0.98), restriction (AUC=0.79, 95% confidence interval=0.75 to 0.93) and impaired diffusion (AUC=0.85, 95% confidence interval=0.59 to 0.92). Co-morbid subclinical coronary artery disease did not modify these relationships.

CONCLUSIONS

Assessment of respiratory symptoms along with a limited number of clinical parameters may serve as a useful and inexpensive clinical tool for identifying RA patients in need of further pulmonary investigation.