Anti-cyclic citrullinated Peptide antibody is associated with interstitial lung disease in patients with rheumatoid arthritis

The prevalence and risk factors of rheumatoid arthritis-associated interstitial lung disease: a systematic review and meta-analysis

BACKGROUND

Interstitial lung disease (ILD) is the most widespread and fatal pulmonary complication of rheumatoid arthritis (RA). Existing knowledge on the prevalence and risk factors of rheumatoid arthritis-associated interstitial lung disease (RA-ILD) is inconclusive. Therefore, we designed this review to address this gap.

MATERIALS AND METHODS

To find relevant observational studies discussing the prevalence and/or risk factors of RA-ILD, EMBASE, Web of Science, PubMed, and the Cochrane Library were explored. The pooled odds ratios (ORs) / hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated with a fixed/ random effects model. While subgroup analysis, meta-regression analysis and sensitivity analysis were carried out to determine the sources of heterogeneity, the I2 statistic was utilized to assess between-studies heterogeneity. Funnel plots and Egger's test were employed to assess publication bias. Following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines, our review was conducted.

RESULTS

A total of 56 studies with 11,851 RA-ILD patients were included in this meta-analysis. The pooled prevalence of RA-ILD was 18.7% (95% CI 15.8-21.6) with significant heterogeneity (I2 = 96.4%). The prevalence of RA-ILD was found to be more likely as a result of several identified factors, including male sex (ORs = 1.92 95% CI 1.70-2.16), older age (WMDs = 6.89, 95% CI 3.10-10.67), having a smoking history (ORs =1.91, 95% CI 1.48-2.47), pulmonary comorbidities predicted (HRs = 2.08, 95% CI 1.89-2.30), longer RA duration (ORs = 1.03, 95% CI 1.01-1.05), older age of RA onset (WMDs =4.46, 95% CI 0.63-8.29), positive RF (HRs = 1.15, 95%CI 0.75-1.77; ORs = 2.11, 95%CI 1.65-2.68), positive ACPA (ORs = 2.11, 95%CI 1.65-2.68), higher ESR (ORs = 1.008, 95%CI 1.002-1.014), moderate and high DAS28 (≥3.2) (ORs = 1.87, 95%CI 1.36-2.58), rheumatoid nodules (ORs = 1.87, 95% CI 1.18-2.98), LEF use (ORs = 1.42, 95%CI 1.08-1.87) and steroid use (HRs= 1.70, 1.13-2.55). The use of biological agents was a protective factor (HRs = 0.77, 95% CI 0.69-0.87).

CONCLUSION(S)

The pooled prevalence of RA-ILD in our study was approximately 18.7%. Furthermore, we identified 13 risk factors for RA-ILD, including male sex, older age, having a smoking history, pulmonary comorbidities, older age of RA onset, longer RA duration, positive RF, positive ACPA, higher ESR, moderate and high DAS28 (≥3.2), rheumatoid nodules, LEF use and steroid use. Additionally, biological agents use was a protective factor.

A nomogram model combining computed tomography-based radiomics and Krebs von den Lungen-6 for identifying low-risk rheumatoid arthritis-associated interstitial lung disease

Objectives

Quantitatively assess the severity and predict the mortality of interstitial lung disease (ILD) associated with Rheumatoid arthritis (RA) was a challenge for clinicians. This study aimed to construct a radiomics nomogram based on chest computed tomography (CT) imaging by using the ILD-GAP (gender, age, and pulmonary physiology) index system for clinical management.

Methods

Chest CT images of patients with RA-ILD were retrospectively analyzed and staged using the ILD-GAP index system. The balanced dataset was then divided into training and testing cohorts at a 7:3 ratio. A clinical factor model was created using demographic and serum analysis data, and a radiomics signature was developed from radiomics features extracted from the CT images. Combined with the radiomics signature and independent clinical factors, a nomogram model was established based on the Rad-score and clinical factors. The model capabilities were measured by operating characteristic curves, calibration curves and decision curves analyses.

Results

A total of 177 patients were divided into two groups (Group I, n = 107; Group II, n = 63). Krebs von den Lungen-6, and nineteen radiomics features were used to build the nomogram, which showed favorable calibration and discrimination in the training cohort [AUC, 0.948 (95% CI: 0.910-0.986)] and the testing validation cohort [AUC, 0.923 (95% CI: 0.853-0.993)]. Decision curve analysis demonstrated that the nomogram performed well in terms of clinical usefulness.

Conclusion

The CT-based radiomics nomogram model achieved favorable efficacy in predicting low-risk RA-ILD patients.

Rheumatoid interstitial lung disease in Canterbury, Aotearoa New Zealand - A retrospective cohort study

BACKGROUND

Rheumatoid arthritis associated interstitial lung disease (RA-ILD), is an important extra-articular manifestation of rheumatoid arthritis (RA). The frequency, risk factors, and prognosis of RA-ILD are incompletely understood.

AIMS

To determine the prevalence and incidence, clinical characteristics and risk factors for development, and outcomes of persons with RA-ILD in the population of the Canterbury District Health Board (CDHB) catchment area.

METHODS

Individuals aged ≥ 18 years with RA, resident in the CDHB catchment area between 1 January 2006 and 31 December 2008 (Period One), and 1 January 2011 to 31 December 2013 (Period Two) were identified by medical record review and followed until 30 June 2019. Individuals with RA-ILD as defined by pre-specified criteria were identified. The association between demographic and clinical characteristics and RA-ILD development and mortality was examined using Cox-proportional hazards models.

RESULTS

The prevalence of RA-ILD per 100,000 was 10.97 (95 % CI 7.53,14.42) for Period One, and 14.74 (95 % CI 10.84,18.63) for Period Two. Among individuals evaluated for risk factors for RA-ILD development, the estimated cumulative incidence of ILD at 10 years was 4.47 % (95 % CI 3.14, 6.14). After adjusting for age, rheumatoid factor positivity (HR 3.73, 95 % CI, 1.32,10.56), extra-articular manifestations other than RA-ILD (HR 4.48, 95 % CI 2.36,8.48), and subcutaneous rheumatoid nodules (HR 4.66, 95 % CI 2.34, 9.26) were associated with increased risk of developing RA-ILD. The standardised mortality ratio for RA-ILD was 3.90 (95 % CI 2.55,5.72) compared to the general population. Extent of ILD on CT chest was associated with mortality (HR for >20% vs. < 20 % 4.47, 95 % CI 1.67,11.96).

CONCLUSIONS

Clinically evident RA-ILD occurred in approximately 5 % of individuals with RA. Mortality was increased almost fourfold compared to the general population. Radiologic extent was the most important prognostic factor.

Etiology and Pathogenesis of Rheumatoid Arthritis-Interstitial Lung Disease

Interstitial lung disease (ILD) is one of the most serious extra-articular complications of rheumatoid arthritis (RA), which increases the mortality of RA. Because the pathogenesis of RA-ILD remains poorly understood, appropriate therapeutic strategies and biomarkers have not yet been identified. Thus, the goal of this review was to summarize and analyze the reported data on the etiology and pathogenesis of RA-ILD. The incidence of RA-ILD increases with age, and is also generally higher in men than in women and in patients with specific genetic variations and ethnicity. Lifestyle factors associated with an increased risk of RA-ILD include smoking and exposure to pollutants. The presence of an anti-cyclic citrullinated peptide antibody, high RA disease activity, and rheumatoid factor positivity also increase the risk of RA-ILD. We also explored the roles of biological processes (e.g., fibroblast-myofibroblast transition, epithelial-mesenchymal transition, and immunological processes), signaling pathways (e.g., JAK/STAT and PI3K/Akt), and the histopathology of RA involved in RA-ILD pathogenesis based on published preclinical and clinical models of RA-ILD in animal and human studies.

Serum CHI3L1 as a biomarker of interstitial lung disease in rheumatoid arthritis

Background

Interstitial lung disease (ILD) is a relatively prevalent extra-articular manifestation of rheumatoid arthritis (RA) and contributes to significant morbidity and mortality. This study aimed to analyze the association between chitinase-3 like-protein-1(CHI3L1) and the presence of RA-ILD.

Methods

A total of 239 RA patients fulfilling the American Rheumatism Association (ACR) 1987 revised criteria were enrolled and subclassified as RA-ILD and RA-nILD based on the results of high-resolution computed tomography scans (HRCT) of the chest. The disease activity of RA was assessed by Disease Activity Score for 28 joints (DAS28) and categorized as high, moderate, low, and remission. Chemiluminescence immunoassays were applied to determine the serum levels of CHI3L1. Univariate analysis was performed and the receiver operating characteristics (ROC) curves were plotted to evaluate the correlation between RA-ILD and CHI3L1.

Results

Among the eligible RA patients studied, 60 (25.1%) patients were diagnosed with RA-ILD. Compared with RA-nILD, RA patients with ILD had significantly higher median age (median [IQR], 68.00 [62.00-71.75] vs 53.00 [40.00-63.00], p<0.001) and a higher proportion of males (21 (35.0%) vs 30 (16.8%), p=0.003). Notably, differences in DAS28 scores between the two groups were not observed. The serum level of CHI3L1 was significantly higher in RA-ILD patients (median [IQR], 69.69 [44.51-128.66] ng/ml vs 32.19 [21.63-56.99] ng/ml, p<0.001). Furthermore, the areas under the curve (AUC) of CHI3L1 attained 0.74 (95% confidence interval [CI], 0.68-0.81, p<0.001) in terms of identifying patients with RA-ILD from those without ILD. Similar trends were seen across the spectrum of disease activity based on DAS28-ESR.

Conclusion

Our findings of elevated serum CHI3L1 levels in RA-ILD patients suggest its possible role as a biomarker to detect RA-ILD noninvasively.

Anti-protein arginine deiminase antibodies are distinctly associated with joint and lung involvement in rheumatoid arthritis

OBJECTIVES

RA is a chronic inflammatory disease in which possible interstitial lung disease (ILD) is an extra-articular manifestation that carries significant morbidity and mortality. RF and ACPA are included in the RA classification criteria but prognostic and diagnostic biomarkers for disease endotyping and RA-ILD are lacking. Anti-protein arginine deiminase antibodies (anti-PAD) are a novel class of autoantibodies identified in RA. This study aimed to assess clinical features, ACPA and anti-PAD antibodies in RA patients with articular involvement and ILD.

METHODS

We retrospectively collected joint erosions, space narrowing, clinical features and lung involvement of a cohort of 71 patients fulfilling the 2010 ACR/EULAR RA classification criteria. Serum samples from these patients were tested for ACPA IgG (QUANTA Flash CCP3), and anti-PAD3 and anti-PAD4 IgG, measured with novel assays based on a particle-based multi-analyte technology (PMAT).

RESULTS

Anti-PAD4 antibodies were significantly associated with radiographic injury (P = 0.027) and erosions (P = 0.02). Similarly, ACPA levels were associated with erosive disease (P = 0.014). Anti-PAD3/4 double-positive patients displayed more joint erosions than patients with anti-PAD4 antibodies only or negative for both (P = 0.014 and P = 0.037, respectively). RA-ILD (15.5%, 11/71 patients) was associated with older age (P < 0.001), shorter disease duration (P = 0.045) and less erosive disease (P = 0.0063). ACPA were elevated in RA-ILD, while anti-PAD4 were negatively associated (P = 0.043).

CONCLUSION

Anti-PAD4 and anti-PAD3 antibodies identify RA patients with higher radiographic injury and bone erosions. In our cohort, ILD is associated with lower radiographic and erosive damage, as well as low levels of anti-PAD4 antibodies.

Patient-level factors predictive of interstitial lung disease in rheumatoid arthritis: a systematic review

Objective Interstitial lung disease (ILD) is an important cause of mortality in some patients with rheumatoid arthritis (RA). Patient-level factors may predict which patients with RA are at the highest risk of developing ILD and are therefore candidates for screening for this complication of the underlying disease.Methods A systematic literature review was performed using PubMed, Embase and Scopus over a 10-year period up to July 2021. Publications reporting patient-level factors in patients with RA with and without ILD that were assessed before development of ILD (or were unchanged over time and therefore could be extrapolated to before development of ILD) were retrieved for assessment of evidence. Genetic variation in MUC5B and treatment with methotrexate were not included in the assessment of evidence because these factors have already been widely investigated for association with ILD.Results We found consistent associations of age, sex, smoking status and autoantibodies with development of ILD. For biomarkers such as Krebs von den Lungen 6, which have been shown to be diagnostic for ILD, there were no publications meeting criteria for this study.Conclusions This analysis provides an initial step in the identification of patient-level factors for potential development of a risk algorithm to identify patients with RA who may be candidates for screening for ILD. The findings represent a useful basis for future research leading to an improved understanding of the disease course and improved care for patients with RA at risk of development and progression of ILD.

Factors associated with interstitial lung disease in patients with rheumatoid arthritis: A systematic review and meta-analysis

OBJECTIVES

Interstitial lung disease (ILD) is frequent in patients with rheumatoid arthritis (RA) and is a potentially life-threatening complication with significant morbidity and mortality. This meta-analysis aims to systematically determine the factors associated with the development of rheumatoid arthritis-related interstitial lung disease (RA-ILD).

MATERIALS AND METHODS

All primary studies which reported the factors associated with of RA-ILD were eligible for the review except case reports. The Cochrane Library, PubMed, Embase, Web of Science, Chinese Biological Medicine Database (CBM), China National Knowledge Infrastructure (CNKI), and WANFANG electronic databases were searched through to December 30, 2022, for studies investigating the factors associated with RA-ILD. The methodological quality assessment of the eligible studies was performed using the Newcastle-Ottawa Scale (NOS). 2 reviewers extracted relevant data independently. Then, weighed mean differences (WMDs) or pooled odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were obtained for the relationships between the factors and RA-ILD. The statistical meta-analysis, subgroup and sensitivity analyses were performed using the Review Manager 5.3, and publication bias with Egger's test were performed using the Stata12.0 software.

RESULTS

A total of 22 articles were screened for a meta-analysis which involved 1887 RA-ILD patients and 8066 RA without ILD patients. Some identified factors that were associated with an increased risk of RA-ILD included male sex (OR = 1.92, 95% CI: 1.54-2.39; P < 0.00001), older age (WMD = 5.77 years, 95% CI: 3.50-8.04; P < 0.00001), longer duration of RA (WMD = 0.80 years, 95% CI 0.12-1.47; P = 0.02), older age at onset of RA (WMD = 6.41 years, 95% CI: 3.17-9.64; P = 0.0001), smoking (OR = 1.69, 95% CI: 1.30-2.18; P < 0.0001). Five factors of laboratory items associated with the development of RA-ILD were evaluated in the meta-analysis. Compared with RA without ILD patients, positive rheumatoid factor (RF) (OR = 1.72, 95% CI: 1.47-2.01; P < 0.00001) and positive anti-citrullinated protein antibodies (ACPA) (OR = 1.58, 95% CI: 1.31-1.90; P < 0.00001) increased the risk of RA-ILD. Meanwhile, RF titer (WMD = 183.62 (IU/mL), 95% CI: 66.94-300.30; P = 0.002) and ACPA titer (WMD = 194.18 (IU/mL), 95% CI: 115.89-272.47; P < 0.00001) were significantly associated with increased risk of RA-ILD. Elevated erythrocyte sedimentation rate (ESR) (WMD = 7.41 (mm/h), 95% CI: 2.21-12.61; P = 0.005) and C-reactive protein (CRP) (WMD = 4.98 (mg/L), 95% CI: 0.76-9.20; P = 0.02) were also significantly associated with the development of the RA-ILD, whereas antinuclear antibody (ANA) positive status was not significantly associated with increased risk of RA-ILD (OR = 1.27, 95% CI: 1.00-1.60; P = 0.05).

CONCLUSIONS

This meta-analysis showed that male gender, older age, longer duration of RA, older age at onset of RA, smoking, positive RF, positive ACPA, elevated RF titer, elevated ACPA titer, higher ESR and higher CRP were associated with RA-ILD.

Peripheral Blood Biomarkers for Rheumatoid Arthritis-Associated Interstitial Lung Disease: A Systematic Review

BACKGROUND

Biomarkers have been proposed as tools to aid in the identification and prognostication of interstitial lung disease (ILD) in rheumatoid arthritis (RA). We performed a systematic review of studies evaluating peripheral blood biomarkers and their association with RA-ILD and its prognosis.

METHODS

Medline, Embase, the Cochrane Library, and Scopus were queried for relevant studies, with the final search update on July 12, 2021. We included studies evaluating peripheral blood biomarkers for the identification and/or prognostication of RA-ILD, extracting the performance of individual biomarkers for identifying RA-ILD, and predicting prognosis. Modified versions of the Quality Assessment of Diagnostic Accuracy Studies 2 and the Quality in Prognosis Studies tools were used for quality assessment.

RESULTS

Seventy studies met eligibility criteria. Study and patient characteristics, analytical methods, strength and consistency of associations, and study quality were heterogeneous. A total of 92 biomarkers were positively associated and 12 were negatively associated with RA-ILD among patients with RA in one or more report. Only a small number of biomarkers were evaluated in multiple cohorts using adjusted analyses. Biomarkers most strongly associated with RA-ILD overlapped with those identified for idiopathic pulmonary fibrosis. Few prognostic biomarkers of RA-ILD were identified.

CONCLUSION

Several peripheral blood biomarkers are associated with the presence of RA-ILD, but few have been assessed in multivariable models, have been externally validated, have discriminated RA-ILD from other lung disease, or have prognosticated the disease course. High-quality studies investigating and validating peripheral biomarkers in RA-ILD are needed before they can be employed in clinical care.

Sexual Dimorphism in Interstitial Lung Disease

Interstitial lung diseases (ILD) are a group of heterogeneous progressive pulmonary disorders, characterised by tissue remodelling and/or fibrotic scarring of the lung parenchyma. ILD patients experience lung function decline with progressive symptoms, poor response to treatment, reduced quality of life and high mortality. ILD can be idiopathic or associated with systemic or connective tissue diseases (CTD) but idiopathic pulmonary fibrosis (IPF) is the most common form. While IPF has a male predominance, women are affected more greatly by CTD and therefore associated ILDs. The mechanisms behind biological sex differences in these progressive lung diseases remain unclear. However, differences in environmental exposures, variable expression of X-chromosome related inflammatory genes and sex hormones play a role. Here, we will outline sex-related differences in the incidence, progression and mechanisms of action of these diseases and discuss existing and novel cellular and pre-clinical studies. Furthermore, we will highlight how sex-differences are not adequately considered in pre-clinical disease models, how gender bias exists in clinical diagnosis and how women are underrepresented in clinical trials. Future action on these observations will hopefully shed light on the role of biological sex in disease development, identify potential targets for intervention and increase female participant numbers in clinical trials.

Risk factors for rheumatoid arthritis-associated interstitial lung disease: a retrospective study

Background

The objective of this study was to assess clinical and imaging features of rheumatoid arthritis (RA) associated with interstitial lung disease (ILD), (RA-ILD) group, in comparison to RA without ILD (RA-C) and to identify the associated factors to ILD.

Methods

This was a retrospective comparative study (from June 2015 to March 2022) including RA patients aged ≥18 years. The RA-C control group was matched according to age (±2 years), gender, and RA duration (±2 years). General data, RA characteristics, ILD features, and treatment modalities were recorded. Statistical analysis was performed to determine the predictive factors of ILD.

Results

A total of 104 patients were included (52 RA-ILD and 52 RA-C); sex ratio was 0.36. Mean age was 66.3±11 years (RA-ILD) versus 65.6±10.8 years (RA-C) (p=0.72). In comparison to RA-C, RA-ILD patients were significantly higher smokers (p=0.01) and physically inactive (p=0.01). Regarding RA features, RA-ILD patients have significantly increased positive anti-citrullinated peptide antibody (ACPA) (p=0.01), ACPA rate (p<0.001), erosive disease (p<0.001), and disease activity score (p<0.001). Mean time to ILD diagnosis was 5.85±7.16 years. Chest high-resolution computed tomography (HRCT) patterns of disease were identified: nonspecific interstitial pneumonia (NSIP) (28.8%), usual interstitial pneumonia (UIP) (17.3%), organizing pneumonia (OP) (25%), acute interstitial pneumonia (13.5%), and respiratory bronchiolitis (3.8%). Multivariate analysis identified smoking, high baseline DAS28 (disease activity score 28) and ACPA positivity as predictive factors of ILD.

Conclusion

Our results confirmed the reported associated factors of ILD in RA (smoking, higher disease activity, ACPA positivity). Thus, we need to target the modifiable factors by supporting and educating RA patients to quit smoking and intensify disease modifying anti-rheumatoid drugs (DMARD) to reach remission.

Demographic, Lifestyle, and Serologic Risk Factors for Rheumatoid Arthritis (RA)-associated Bronchiectasis: Role of RA-related Autoantibodies

OBJECTIVE

To investigate demographic, lifestyle, and serologic risk factors for isolated rheumatoid arthritis (RA)-associated bronchiectasis (RA-BR) that is not a result of interstitial lung disease (ILD).

METHODS

We performed a case-control study using patients with RA from the Mass General Brigham Biobank. We reviewed the records of all patients with RA meeting the 2010 American College of Rheumatology/European Alliance of Associations for Rheumatology criteria with computed tomography (CT) chest imaging to identify RA-BR cases and controls with RA and RA-related lung disease. For each patient, the CT chest imaging that was performed closest to enrollment was independently reviewed by 2 radiologists for the presence of RA-related lung diseases. Cases had clinical and radiologic evidence of RA-BR without interstitial lung abnormalities on imaging. Controls had RA and no evidence of bronchiectasis or ILD. We examined the associations between demographic, lifestyle, and serologic factors with RA-BR using multivariable logistic regression.

RESULTS

We identified 57 cases of isolated RA-BR and 360 RA controls without RA-related lung disease. In multivariable models, RA-BR was associated with older age at RA onset (OR 1.37 per 10 years, 95% CI 1.02-1.82), lower BMI at RA diagnosis (OR 0.94 per kg/m2, 95% CI 0.89-0.99), seropositive RA (OR 3.96, 95% CI 1.84-8.53), positive rheumatoid factor (OR 4.40, 95% CI 2.14-9.07), and positive anticyclic citrullinated peptide (OR 3.47, 95% CI 1.65-7.31). Higher titers of RA-related autoantibodies were associated with higher odds of RA-BR.

CONCLUSION

Seropositivity, older age at RA diagnosis, and lower BMI at RA onset were associated with isolated bronchiectasis in RA that was not a result of ILD. These findings expand the list of potential risk factors for RA-BR and suggest a pathogenic link between airway inflammation and RA-related autoantibodies.

Association of sinusitis and upper respiratory tract diseases with incident rheumatoid arthritis: A case-control study

OBJECTIVE

We aimed to determine whether specific respiratory tract diseases are associated with increased rheumatoid arthritis (RA) risk.

METHODS

This case-control study within the Mass General Brigham Biobank matched newly diagnosed RA cases to three controls on age, sex, and electronic health record history. We identified RA using a validated algorithm and confirmed by medical record review. Respiratory tract disease exposure required one inpatient or two outpatient codes at least two years before index date of RA clinical diagnosis or matched date. Logistic regression models calculated odds ratios (OR) for RA with 95% confidence intervals (CI), adjusting for confounders. We then stratified by serostatus ("seropositive" was positive rheumatoid factor and/or anti-citrullinated protein antibodies) and smoking.

RESULTS

We identified 741 RA cases and 2,223 controls (both median age 55, 76% female). Acute sinusitis (OR 1.61, 95% CI:1.05,2.45), chronic sinusitis (OR 2.16, 95% CI:1.39,3.35), and asthma (OR 1.39, 95% CI:1.03,1.87) were associated with increased risk of RA. Acute respiratory tract disease burden during the pre-index exposure period was also associated with increased RA risk (OR 1.30 per 10 codes, 95% CI:1.08,1.55). Acute pharyngitis was associated with seronegative (OR 1.68, 95% CI:1.02,2.74) but not seropositive RA; chronic rhinitis/pharyngitis was associated with seropositive (OR 2.46, 95% CI:1.01,5.99) but not seronegative RA. Respiratory tract diseases tended towards higher associations in smokers, especially >10 packyears (OR 1.52, 95% CI:1.02,2.27; p=0.10 for interaction).

CONCLUSION

Acute/chronic sinusitis and pharyngitis and acute respiratory burden increased RA risk. The mucosal paradigm of RA pathogenesis may involve the upper respiratory tract.

Bronchiectasis is as crucial as interstitial lung disease in the severe pneumonia that occurs during treatment with biologic DMARDs in rheumatoid arthritis: a retrospective cohort study in a single facility

Interstitial lung disease (ILD) carries a risk for severe pneumonia in patients with rheumatoid arthritis (RA). Bronchiectasis, another risk of severe pneumonia, has not been well elucidated in RA. We investigated the types of respiratory diseases in RA and correlated them to severe pneumonia during the course of treatment using biologic DMARDs (bDMARDs), with special attention to bronchiectasis and ILD. RA patients were examined by computed tomography before starting bDMARDs and divided into three groups: normal, bronchiectasis and ILD. The log-rank test and Dunnett's multiple comparisons test were employed for the statistical analysis. Among 424 patients, 350 were categorized as normal, 32 as having bronchiectasis, and 42 as having ILD. Two in the normal group, three in the bronchiectasis group and four in the ILD group developed severe pneumonia. The log-rank test showed a significant difference among the three groups (p < 0.0001). The pneumonia-free rates in the bronchiectasis and ILD groups were significantly lower than the normal group, respectively, with Dunnett's multiple comparison test (p < 0.0001). This study suggests that the bronchiectasis that occurs in RA carries a risk of severe pneumonia during treatment with bDMARDs that is comparable to ILD.

Interstitial lung disease throughout the rheumatoid arthritis disease course

PURPOSE OF REVIEW

To summarize the current understanding of rheumatoid arthritis-associated interstitial lung disease (RA-ILD) throughout the rheumatoid arthritis (RA) disease course from preclinical to established disease.

RECENT FINDINGS

ILD is a serious extra-articular manifestation of RA. Multiple studies have demonstrated a high prevalence of both subclinical and clinical ILD throughout the RA disease course. Investigations of patients without RA have demonstrated an association between RA-related autoantibodies like anticitrullinated protein antibodies (ACPA) and interstitial abnormalities on lung imaging. A significant proportion of RA-ILD patients develop ILD prior to articular manifestations, suggesting that the lung plays a central role in RA development, perhaps through ACPA production. RA-ILD also occurs in early RA, when exuberant autoantibody production and systemic inflammation may propagate pulmonary disease activity. In patients with established RA, a high burden of subclinical and clinical ILD results in significant morbidity, mortality, and healthcare expenditure. Multiple epidemiologic and genetic risk factors, as well as serum biomarkers, have been associated with RA-ILD.

SUMMARY

Subclinical and clinical ILD occur frequently in preclinical, early, and established RA and may play a key role in RA-related autoantibody production and disease progression. Further studies are needed to better understand the risk factors, prognosis, and potential therapies for RA-ILD.

Analysis of Clinical-Analytical Characteristics in Patients with Rheumatoid Arthritis and Interstitial Lung Disease: Case-Control Study

OBJECTIVES

To study the differences between rheumatoid arthritis (RA)-interstitial lung disease (ILD) patients and RA patients without ILD in severity markers and disease activity and to identify factors associated with the presence of ILD in RA patients.

PATIENTS AND METHODS

Patients: RA-ILD patients selected from a multicentre cohort in Andalusia, Spain.

CONTROLS

RA-patients without ILD paired by sex, age and disease duration.

PROTOCOL

RA patients are reviewed every 3-6months in rheumatology consultation. All patients are reviewed according to a predetermined protocol with systematic data collection.

OUTCOMES

description of ILD type, differences in severity markers and disease activity in both groups. Other variables: ILD type by imaging technique (HRCT): nonspecific interstitial pneumonia (NSIP)/usual interstitial pneumonia (UIP). Lung function by PTF. Activity and severity markers of arthritis by DAS28-ESR, HAQ, RF, ACPA and erosions. Treatment with DMARD.

STATISTICAL ANALYSIS

descriptive and paired T-test or Chi-square test followed by binary logistic regression (DV: ILD in patients with RA).

RESULTS

Eighty-two patients were included, 41 RA-ILD and 41 RA controls. RF and ACPA positivity, serositis and osteoporosis were more frequent in RA-ILD patients. No significant differences in DAS28 were observed (P=.145) between RA-ILD and RA control patients. RA-ILD patients presented worse HAQ scores (P=.006). All patients were treated with disease modifying antirheumatic drugs (DMARDs). The risk of developing ILD in RA patients is tripled by a history of smoking or the presence of erosive arthritis (R²=.36).

CONCLUSIONS

The results of our study support the higher frequency of UIP and NSIP in RA patients. DLCO is the most sensitive parameter to detect ILD in RA patients. Our study showed that ILD in RA patients was associated with RA severity (presence of erosions and ACPA) and with a history of smoking.

Systematic review and meta-analysis of the risk of rheumatoid arthritis-associated interstitial lung disease related to anti-cyclic citrullinated peptide (CCP) antibody

OBJECTIVE

To clarify the risk of rheumatoid arthritis-associated interstitial lung disease (RA-ILD) related to anti-cyclic citrullinated peptide (CCP) antibody.

ELIGIBILITY CRITERIA

Patients with RA with and without ILD were eligible. The primary outcome was the prevalence or incidence of ILD. Primary studies of any design aside from a case report were eligible.

INFORMATION SOURCES

Medline, EMBASE, Science Citation Index Expanded and Cochrane Central Register of Controlled Trials were searched from the inception through 12 November 2019.

DATA EXTRACTION AND RISK OF BIAS

Two reviewers independently selected eligible reports, extracted relevant data and assessed risk of bias using a modified Quality in Prognostic Studies tool.

DATA SYNTHESIS

Meta-analysis was conducted using a random-effects model.

QUALITY OF EVIDENCE

The Grades of Recommendation, Assessment, Development and Evaluation system was applied.

RESULTS

Among 29 out of 827 records retrieved through electronic databases and four additional reports identified from other sources, 29 studies were focused for the review. A total of 10158 subjects were included and the mean age at inclusion was between 45.8 and 63.9 years. The mean RA duration was between 4.3 and 14.9 years. The positivity of anti-CCP antibody ranged from 50.7% to 95.8%. All studies except for two were deemed as high risk of bias. A pooled analysis of univariate results demonstrated that the presence of anti-CCP antibody was significantly associated with RA-ILD with an OR of 2.10 (95% CI: 1.59 to 2.78). Similarly, the titre of anti-CCP antibody was significantly higher for RA-ILD with a standardised mean difference of 0.42 (95% CI: 0.20 to 0.65). These results were confirmed by multivariate analysis in the majority of studies and consistent by any subgroup and sensitivity analyses.

CONCLUSION

The presence and higher titres of anti-CCP antibody were suggested to be significantly associated with an increased risk of RA-ILD. However, the quality of evidence was rated as low or very low.

Utility of pulmonary ultrasound to identify interstitial lung disease in patients with rheumatoid arthritis

OBJECTIVES

To analyze the diagnostic utility of lung ultrasound (US) to detect interstitial lung disease (ILD) in rheumatoid arthritis (RA) patients comparing with high-resolution computed tomography (HRCT) PATIENTS AND METHODS: We performed a cross-sectional, observational study in patients with RA-ILD (cases) controlled with a group of RA patients without ILD (controls) paired by sex, age, and time of disease evolution. Patients were assessed using HRCT, PFT, and US. The main variables were B-line number, evaluation of the lung-US score already described, pleural irregularities, and A pattern US lost. ROC curve analysis was performed to establish the cut-off point of the US B-lines number for detecting the presence of significant RA-ILD in relation to HRCT, and logistic regression analysis was performed to identify the intercostal spaces.

RESULTS

Seventy-one patients were included, 35 (49.2%) with ILD-RA and 36 (50.8%) RA controls. Regarding US score, we found that the detection of 5.5 lines in a reduced score of 8 intercostal spaces had a sensitivity = 62.2%, specificity = 91.3%, PPV = 88.4%, and NPV = 69.5%. In multivariate analysis, the intercostal spaces which showed independent association with ILD were 3rd right anterior axillary space (OR [IC 95%] 19.0 [1.3-27.5]), 8th right posterior axillary space (OR [IC 95%] 0.04 [0.0-0.6]), 8th right subscapular space (OR [IC 95%] 16.5 [1.8-45.5]), 9th right paravertebral space (OR [IC 95%] 7.11 [1.0-37.1]), and 2nd left clavicular middle space (OR [IC 95%] 21.9 [1.26-37.8]).

CONCLUSIONS

Lung ultrasound could be a useful tool for ILD diagnosis associated with rheumatoid arthritis. A 8-space reduced score showed a similar total predictive capacity than 72-space score. Key Points • Lung ultrasound could be a useful tool for ILD diagnosis associated with rheumatoid arthritis. • The 72-space evaluation is highly sensitive, whereas a simplified score enables a more specific and faster diagnosis. • The number of B lines is correlated with DLCO, ACPA, inflammatory activity, and physical function.

Respiratory Diseases as Risk Factors for Seropositive and Seronegative Rheumatoid Arthritis and in Relation to Smoking

OBJECTIVE

The link and interplay between different airway exposures and rheumatoid arthritis (RA) risk are unclear. This study was undertaken to determine whether respiratory disease is associated with development of RA, and specifically to examine this relationship by RA serostatus and smoking exposure.

METHODS

Using data from the Epidemiological Investigation of Rheumatoid Arthritis study, this analysis included 1,631 incident RA cases and 3,283 matched controls recruited from 2006 to 2016. Linking these individuals to the National Patient Register provided information on past acute or chronic, upper or lower respiratory disease diagnoses. For each disease group, we estimated adjusted odds ratios (OR_adj ) with 95% confidence intervals (95% CI) for RA, using logistic regression models adjusted for age, sex, residential area, body mass index, and education both overall and stratified by anti-citrullinated protein antibody (ACPA)/rheumatoid factor (RF) status and by smoking status.

RESULTS

Respiratory disease diagnoses were associated with risk of RA, with an OR_adj of 1.2 for acute upper respiratory disease (95% CI 0.8-1.7), 1.4 for chronic upper respiratory disease (95% CI 1.1-1.9), 2.4 for acute lower respiratory disease (95% CI 1.5-3.6), and 1.6 for chronic lower respiratory disease (95% CI 1.5-3.6). These associations were present irrespective of RF or ACPA status, though the association was somewhat stronger for ACPA/RF-positive than ACPA/RF-negative RA. The association between any respiratory disease and RA was stronger for nonsmokers (OR_adj 2.1 [95% CI 1.5-2.9]) than for smokers (OR_adj 1.2 [95% CI 0.9-1.5]).

CONCLUSION

Respiratory diseases increase the risk for both seropositive and seronegative RA, but only among nonsmokers. These findings raise the hypothesis that smoking and airway disease are associated with RA development through partly different mechanisms.

Lifestyle and Clinical Risk Factors for Incident Rheumatoid Arthritis-associated Interstitial Lung Disease

OBJECTIVE

To determine the association between novel lifestyle factors on risk of rheumatoid arthritis (RA)-associated interstitial lung disease (ILD), define the threshold at which smoking increases RA-ILD risk, and calculate the degree to which known lifestyle and clinical factors predict RA-ILD.

METHODS

This nested case-control study matched incident RA-ILD cases to RA non-ILD controls on age, sex, RA duration, rheumatoid factor, and time from exposure assessment to RA-ILD. Exposures included education, BMI, smoking, anticyclic citrullinated peptide antibodies, race, joint erosions, rheumatoid nodules, C-reactive protein (CRP), disease activity score, functional status, disease-modifying antirheumatic drug use, and glucocorticoid use. OR for each exposure on risk of RA-ILD were obtained from logistic regression models. Area under the curve (AUC) was calculated based on all lifestyle and clinical exposures.

RESULTS

We identified 84 incident RA-ILD cases and 233 matched controls. After adjustment, obesity, high-positive CRP (≥ 10 mg/L), and poor functional status (multidimensional Health Assessment Questionnaire [MDHAQ] ≥ 1) were associated with increased risk of RA-ILD (OR 2.42, 95% CI 1.11-5.24 vs normal BMI; OR 2.61, 95% CI 1.21-5.64 vs CRP < 3 mg/L; OR 3.10, 95% CI 1.32-7.26 vs MDHAQ < 0.2). Smoking 30 pack-years or more was strongly associated with risk of RA-ILD compared to never smokers (OR 6.06, 95% CI 2.72-13.5). Together, lifestyle and clinical risk factors for RA-ILD had an AUC of 0.79 (95% CI 0.73-0.85).

CONCLUSION

Obesity, CRP, functional status, and extensive smoking may be novel risk factors for RA-ILD that may be useful for RA-ILD risk assessment and prevention. The overall ability to predict RA-ILD remains modest.

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.

Anti-HLA Class II Antibodies Correlate with C-Reactive Protein Levels in Patients with Rheumatoid Arthritis Associated with Interstitial Lung Disease

The pathogenesis of Rheumatoid Arthritis (RA) is not fully understood, probably influenced by genetic and environmental factors. Interstitial Lung Disease (ILD) is an extra-articular manifestation of RA, which contributes significantly to morbidity and mortality. The identification of anti-HLA antibodies has been useful in the transplantation field; however, its contribution to autoimmune diseases as RA has not been fully studied. We aimed to determine the presence of anti-HLA antibodies in RA patients with and without ILD and its possible association with clinical and biochemical markers. One-hundred and forty-seven RA patients, of which 65 had ILD (RA-ILD group), were included. Sera samples for Anti-HLA Class II LABScreen panel-reactive antibodies (PRA) were analyzed. In both groups, women predominated, and lung function was worse in patients with ILD. The anti-CCP+ (UI/mL) was higher in the RA group in comparison to RA-ILD (p < 0.001). Expositional risk factors (tobacco smoking and biomass-burning smoke) were higher in RA-ILD patients. PRA+ was identified in ~25% RA-ILD patients, while ~29% in the RA group. The CRP levels have a positive correlation with the percentage of reactivity (%PRA, p = 0.02, r2 = 0.60) in the RA-ILD group. In conclusion, anti-HLA antibodies correlate with C-reactive protein levels in RA patients with ILD.

Malondialdehyde-Acetaldehyde Adducts and Antibody Responses in Rheumatoid Arthritis-Associated Interstitial Lung Disease

OBJECTIVE

To compare serum anti-malondialdehyde-acetaldehyde (anti-MAA) antibody levels and MAA expression in lung tissue from patients with rheumatoid arthritis-associated interstitial lung disease (RA-ILD) to those found in controls.

METHODS

Anti-MAA antibody (IgA, IgM, IgG) concentrations were measured in patients with RA-ILD and compared to those of RA patients with chronic obstructive pulmonary disease (COPD) and RA patients without lung disease. Associations between anti-MAA antibody with RA-ILD were assessed using multivariable logistic regression. Lung tissue from patients with RA-ILD, other ILD, or emphysema, and from controls (n = 3 per group) were stained for MAA, citrulline, macrophages (CD68), T cells (CD3), B cells (CD19/CD27), and extracellular matrix proteins (type II collagen, fibronectin, vimentin). Tissue expression and colocalization with MAA were quantified and compared.

RESULTS

Among 1,823 RA patients, 90 had prevalent RA-ILD. Serum IgA and IgM anti-MAA antibody concentrations were higher in RA-ILD than in RA with COPD or RA alone (P = 0.005). After adjustment for covariates, the highest quartiles of IgA anti-MAA antibody concentration (odds ratio 2.09 [95% confidence interval 1.11-3.90]) and IgM (odds ratio 2.23 [95% confidence interval 1.19-4.15]) were significantly associated with the presence of RA-ILD. MAA expression in RA-ILD lung tissue was greater than in tissue from all other groups (P < 0.001), and it colocalized with citrulline (r = 0.79), CD19+ B cells (r = 0.78), and extracellular matrix proteins (type II collagen [r = 0.72] and vimentin [r = 0.77]) to the greatest degree in RA-ILD.

CONCLUSION

Serum IgA and IgM anti-MAA antibody is associated with ILD among RA patients. MAA is highly expressed in RA-ILD lung tissue, where it colocalizes with other RA autoantigens, autoreactive B cells, and extracellular matrix proteins, highlighting its potential role in the pathogenesis of RA-ILD.

Related factors, increased mortality and causes of death in patients with rheumatoid arthritis-associated interstitial lung disease

Objectives: Interstitial lung disease (ILD) is a life-threatening extra-articular manifestation of rheumatoid arthritis (RA). We aimed to clarify the relationship between chronic ILD with a pattern of usual interstitial pneumonia (UIP) or non-UIP and mortality in RA patients.Methods: We retrospectively surveyed information of consecutive RA patients who visited our hospital from 2009 to 2014. The relationship between their mortality and chronic ILD (UIP or non-UIP) detected by high-resolution computed tomography was examined.Results: Of 2702 patients enrolled, 261 (9.7%) had chronic ILD and among these 120 had a UIP pattern. At the onset of RA, the prevalence of chronic ILD was 6%. Patients with chronic ILD had a higher mortality than those without. The most frequent cause of death was pneumonia including acute exacerbation (AE) of chronic ILD. Lung cancer death was frequently identified in deceased patients with chronic ILD with a UIP pattern compared with the other decedents (p=.062). The estimated mortality of lung cancer in patients with chronic ILD with a UIP pattern was five times higher than the general population.Conclusion: RA patients with ILD with a UIP pattern have a high mortality rate and are prone to die of AE or lung cancer.

Association of anti-cyclic citrullinated peptide antibody with clinical features in patients with psoriatic arthritis

Background: Although anti-cyclic citrullinated peptide antibody (anti-CCP Ab) is reported to be found in 5-20% of patients with psoriatic arthritis (PsA), its clinical significance has not been elucidated.Objective: To clarify the association of anti-CCP Ab with clinical features in PsA.Methods: Patients were enrolled who fulfilled the classification criteria for psoriatic arthritis (CASPAR) criteria and visited our hospital. We retrospectively compared clinical characteristics between those who were positive and negative for anti-CCP Ab and further compared changes in disease activity in the patients treated with biological disease-modifying anti-rheumatic drugs (DMARDs).Results: We examined 41 patients (11 females), seven were anti-CCP Ab-positive and 34 were negative. Age (55.0 ± 15.1 years old) and frequency of lung involvements (71.4%) in the anti-CCP Ab-positive group were significantly higher than those (40.0 ± 16.0 and 0%, respectively) in the negative group (p  <  .05). Rheumatoid factor (RF) titer (749.4 ± 860.7 U/mL) and MMP-3 (604.8 ± 1060.6) in the anti-CCP Ab-positive group was significantly higher than that (3.6 ± 4.4 U/mL and 111.2 ± 77.4, respectively) in the negative group (p  <  .05). Five patients were treated with tumor necrosis factor (TNF) inhibitors (infliximab (IFX): 3 and adalimumab (ADA): 2) in the anti-CCP Ab-positive group, while in the negative group there were 11 (IFX: 6, ADA: 4, and etanercept (ETN): 1). Within 6 months of treatment, arthritis did not improve with TNF inhibitors in the anti-CCP Ab-positive group, whereas it improved significantly in the negative group.Conclusion: In patients with PsA, anti-CCP Ab might be related to lung involvements, elderly onset, RF and MMP-3 titers, and resistance to TNF inhibitor.

Autoreactive T cells to citrullinated HSP90 are associated with interstitial lung disease in rheumatoid arthritis

AIM

Previous analysis of comparative anti-citrullinated heat shock protein 90 (citHSP90) antibody profiles between bronchoalveolar lavage fluid and serum indicates that the lung plays a direct role in shaping the immune repertoire of rheumatoid arthritis-associated interstitial lung disease (RA-ILD).

METHODS

To address the contribution of citHSP90β-specific T cells in this process, we evaluated in vitro cytokine responses to citHSP90β in RA patients with different stages of ILD as well as in controls with non-RA connective tissue disease-associated ILD (CTD-ILD). Cultures derived from whole blood were individually stimulated with HSP90β, citHSP90β, citrullinated BSA, or no antigen. The concentrations of 13 cytokines and chemokines in the plasma supernatant were then measured using Luminex xMAP technology.

RESULTS

CitHSP90β induced significantly higher levels of interferon-γ (IFN-γ) levels in RA-ILD (interstitial lung abnormalities = 2 + 3) groups compared to the RA-no ILD group (P = 0.01), but did not stimulate the production of other cytokines (P > 0.05). Furthermore, citHSP90β did not stimulate the production of IFN-γ or other cytokines in those individuals with non-RA CTD-ILD.

CONCLUSION

Overall, the production of IFN-γ by T cells stimulated with citHSP90β demonstrates a bias toward TH1 immune responses that are likely involved in the pathogenesis of RA-ILD.

Interleukin-18 is associated with the presence of interstitial lung disease in rheumatoid arthritis: a cross-sectional study

OBJECTIVE

Serum interleukin-18 (IL-18) levels are increased in patients with interstitial lung disease (ILD). In addition, IL-18 levels are increased in patients with rheumatoid arthritis (RA) and are associated with arthritis activity. We determined whether increased IL-18 levels are associated with ILD in RA.

METHOD

RA patients were enrolled using an RA cohort database. Plasma IL-18 levels were measured by enzyme-linked immunosorbent assay. ILD was determined by a pulmonologist and a radiologist based on chest radiography and computed tomography findings. IL-18 levels for RA with ILD and RA without ILD were compared. Associations between ILD and various markers including IL-18 and confounding factors (e.g. smoking history) were investigated by logistic regression analysis. Diagnostic values of IL-18 for the presence of ILD were investigated using receiver operating characteristics curve analysis.

RESULTS

ILD was complicated in 8.2% (n = 26) of the study population (N = 312). Plasma IL-18 levels were higher for RA patients with ILD than for RA patients without ILD (721.0 ± 481.4 vs 436.8 ± 438.9 pg/mL, p < 0.001). IL-18, Krebs von den Lungen-6, and anti-cyclic citrullinated peptide antibody titre and glucocorticoid doses were independently associated with the presence of ILD during multivariate logistic regression analysis. Sensitivity and specificity of IL-18 levels for the detection of ILD in RA patients were 65.3% and 76.3%, respectively (area under the curve = 0.73).

CONCLUSION

Plasma IL-18 levels were higher for RA patients with ILD than for those without ILD. Increased IL-18 levels were associated with the presence of ILD.

Expression of CCR3, SOX5 and LC3 in patients with elderly onset rheumatoid arthritis and the clinical significance

This study investigated the expression of C-C chemokine receptor type 3 (CCR3), transcription factor SOX5 (SOX5) and microtubule-associated protein 1 light chain 3 (LC3) in patients with elderly onset rheumatoid arthritis (EORA) and the clinical significance. Ninety patients with elderly onset rheumatoid arthritis were selected in our hospital from January to December in 2016 to serve as patient group. At the same time, 50 healthy people were selected as control group. Levels of CCR3, SOX5 and LC3 in serum of two groups were detected by enzyme-linked immunosorbent assay (ELISA). Expression levels of CCR3, SOX5 and LC3 mRNA in peripheral blood mononuclear cells (PBMCs) were detected by reverse transcription-PCR (RT-PCR). Expression level of CCR3 mRNA in patient group was 0.752±0.054, which was significantly higher than that in control group (0.287±0.032, t=8.932, P<0.05). Levels of CCR3, SOX5 and LC3 in serum of patients in patient group were significantly higher than those in control group (P<0.05). Positive correlations were found between serum levels of CCR3 and SOX5 (r=0.613, P<0.05), serum levels of CCR3 and LC3 (r=0.637, P<0.05), and serum levels of SOX5 and LC3 (r=0.645, P<0.05). CCR3, SOX5 and LC3 are highly expressed in PBMC and serum, which may be closely related to the occurrence and development of EORA. These indexes may be used as indicators of clinical diagnosis and prognosis of patients with EORA.

Role of Autoantibodies in the Diagnosis of Connective-Tissue Disease ILD (CTD-ILD) and Interstitial Pneumonia with Autoimmune Features (IPAF)

The diagnosis of interstitial lung disease (ILD) requires meticulous evaluation for an underlying connective tissue disease (CTD), with major implications for prognosis and management. CTD associated ILD (CTD-ILD) occurs most commonly in the context of an established CTD, but can be the first and/or only manifestation of an occult CTD or occur in patients who have features suggestive of an autoimmune process, but not meeting diagnostic criteria for a defined CTD-recently defined as "interstitial pneumonia with autoimmune features" (IPAF). The detection of specific autoantibodies serves a critical role in the diagnosis of CTD-ILD, but there remains a lack of data to guide clinical practice including which autoantibodies should be tested on initial assessment and when or in whom serial testing should be performed. The implications of detecting autoantibodies in patients with IPAF on disease behaviour and management remain unknown. The evaluation of CTD-ILD is challenging due to the heterogeneity of presentations and types of CTD and ILD that may be encountered, and thus it is imperative that immunologic tests are interpreted in conjunction with a detailed rheumatologic history and examination and multidisciplinary collaboration between respiratory physicians, rheumatologists, immunologists, radiologists and pathologists.

Biologics-induced interstitial lung diseases in rheumatic patients: facts and controversies

INTRODUCTION

Interstitial lung disease (ILD) is a common, devastating pulmonary complication. An increased number of reports suggesting that biological disease modifying antirheumatic drugs (DMARDs) induced or exacerbated ILDs in rheumatoid arthritis (RA) patients has garnered increased attention. Areas covered: This article discusses ILDs induced by or exacerbated during biological therapy in RA patients. The article summarizes the efficacy and safety of a variety of licensed and off-label biologics clinically used for rheumatic diseases, focusing on the onset or exacerbation of RA-associated ILDs (RA-ILDs) in RA patients treated with biologics targeting tumor necrosis factor, CD20, interleukin 1 (IL-1) and IL-6 receptors. Additionally, the pathogenesis of RA-ILDs is discussed. Expert opinion: To some extent, the possibility of biologic-induced RA-ILDs increases the difficulty in choosing an optimal regimen for RA treatment with biological agents, as the relationship between biological therapy safety and the induction or exacerbation of RA-ILDs has not been established. A framework to assess baseline disease severity, particularly standardizing the evaluation of the pulmonary condition stage in RA patients and monitoring the outcome during the biological therapy treatment, is highly needed and may substantially help guide treatment decisions and predict the treatment benefits.

Efficacy of intensive immunosuppression in exacerbated rheumatoid arthritis-associated interstitial lung disease

OBJECTIVES

Acute or subacute exacerbations are recognized as a severe complication of rheumatoid arthritis-associated interstitial lung disease (RA-ILD). Nevertheless, the role of intensive immunosuppression in RA-ILD remains elusive. We attempted to evaluate the clinical characteristics and efficacy of immunosuppressive treatment in exacerbated RA-ILD.

METHODS

Clinical data, including respiratory function, imaging, treatment, and prognosis, were retrospectively collected for 17 patients with RA-ILD who required hospitalization at the University of Tokyo Hospital due to an acute exacerbation (12 patients) or subacute exacerbation (5 patients).

RESULTS

Patients with RA-ILD demonstrated a significantly higher titers of anticyclic citrullinated peptide antibodies compared with RA patients in Japanese Ninja registry, suggesting the role of adaptive immunity. Immunosuppressive treatment suppressed the deterioration of pulmonary functions with improved ground grass opacity and consolidation. In particular, in patients with less fibrosis on computed tomography (CT) images showed a better response to treatment. Although five patients treated with combination therapy, including cyclophosphamide, showed a severely decreased lung volume, these intensive therapies provided a good prognosis without fatalities for the average observation period of 474 days.

CONCLUSIONS

Immunosuppressive therapy is effective for exacerbations of RA-ILD. For severe cases with low respiratory function, intensive therapy, including cyclophosphamide, has a potential to improve the prognosis.

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.

Rheumatoid Arthritis, Anti-Cyclic Citrullinated Peptide Positivity, and Cardiovascular Disease Risk in the Women's Health Initiative

OBJECTIVE

To evaluate the incidence of cardiovascular disease (CVD) morbidity and mortality over the course of 10 years among the more than 160,000 postmenopausal women in the Women's Health Initiative (WHI) in relation to self-reported rheumatoid arthritis (RA), taking disease-modifying antirheumatic drugs (DMARDs), anti-cyclic citrullinated peptide (anti-CCP) positivity, rheumatoid factor (RF) positivity, CVD risk factors, joint pain, and inflammation (white blood cell count and interleukin-6 levels).

METHODS

Anti-CCP and RF were measured in a sample of WHI participants with self-reported RA (n = 9,988). RA was classified as self-reported RA plus anti-CCP positivity and/or taking DMARDs. Anti-CCP-negative women with self-reported RA and not taking DMARDs were classified as having "unverified RA."

RESULTS

Age-adjusted rates of coronary heart disease (CHD), stroke, CVD, fatal CVD, and total mortality were higher in women with RA than in women with no reported RA, with multivariable-adjusted hazard ratios of 1.46 (95% confidence interval [95% CI] 1.17-1.83) for CHD and 2.55 (95% CI 1.86-3.51) for fatal CVD. Among women with RA, anti-CCP positivity and RF positivity were not significantly associated with higher risk of any outcomes, despite slightly higher risk of death for those who were anti-CCP positive than for those who were anti-CCP negative. Joint pain severity and CVD risk factors were strongly associated with CVD risk, even in women with no reported RA. CVD incidence was increased in women with RA versus women with no reported RA at almost all risk factor levels, except for low levels of joint pain or inflammation. Among women with RA, inflammation was more strongly associated with fatal CVD and total mortality than with CHD or CVD.

CONCLUSION

Among postmenopausal women, RA was associated with 1.5-2.5-fold higher CVD risk. CVD risk was strongly associated with CVD risk factors, joint pain severity, and inflammation, but not with anti-CCP positivity or RF positivity.

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.

Anti-Cyclic Citrullinated Peptide Antibodies and Severity of Interstitial Lung Disease in Women with Rheumatoid Arthritis

Objective. To evaluate whether serum titers of second-generation anticyclic citrullinated peptide antibodies (anti-CCP2) are associated with the severity and extent of interstitial lung disease in rheumatoid arthritis (RA-ILD). Methods. In across-sectional study, 39 RA-ILD patients confirmed by high-resolution computed tomography (HRCT) were compared with 42 RA without lung involvement (RA only). Characteristics related to RA-ILD were assessed in all of the patients and serum anti-CCP2 titers quantified. Results. Higher anti-CCP2 titers were found in RA-ILD compared with RA only (medians 77.9 versus 30.2 U/mL, P < 0.001). In the logistic regression analysis after adjustment for age, disease duration (DD), smoke exposure, disease activity, functioning, erythrocyte sedimentation rate, and methotrexate (MTX) treatment duration, the characteristics associated with RA-ILD were higher anti-CCP2 titers (P = 0.003) and + RF (P = 0.002). In multivariate linear regression, the variables associated with severity of ground-glass score were anti-CCP2 titers (P = 0.02) and with fibrosis score DD (P = 0.01), anti-CCP2 titers (P < 0.001), and MTX treatment duration (P < 0.001). Conclusions. Anti-CCP2 antibodies are markers of severity and extent of RA-ILD in HRCT. Further longitudinal studies are required to identify if higher anti-CCP2 titers are associated with worst prognosis in RA-ILD.

Interstitial lung disease in rheumatoid arthritis: Current concepts in pathogenesis, diagnosis and therapeutics

Rheumatoid arthritis (RA) is the most common chronic autoimmune inflammatory joint disease. RA-associated interstitial lung disease (RA-ILD) is a major extra-articular complication and causes symptoms that lead to a deterioration in the quality of life, high utilization of health resources, and an increased risk of earlier mortality. Early in the course of RA-ILD, symptoms are highly variable, making the diagnosis difficult. Therefore, a rational diagnostic strategy that combines an adequate clinical assessment with the appropriate use of clinical tests, including pulmonary function tests and high-resolution computed tomography, should be used. In special cases, lung biopsy or bronchioalveolar lavage should be performed to achieve an early diagnosis. Several distinct histopathological subtypes of RA-ILD are currently recognized. These subtypes also have different clinical presentations, which vary in therapeutic response and prognosis. This article reviews current evidence about the epidemiology of RA-ILD and discusses the varying prevalence rates observed in different studies. Additionally, aspects of RA-ILD pathogenesis, including the role of cytokines and other molecules such as autoantibodies, as well as the evidence linking several drugs used to treat RA with lung damage will be discussed. Some aspects of the clinical characteristics of RA-ILD are noted, and diagnostic strategies are reviewed. Finally, this article analyzes current treatments for RA-ILD, including immunosuppressive therapies and biologic agents, as well as other therapeutic modalities. The prognosis of this severe complication of RA is discussed. Additionally, this paper examines updated evidence from studies identifying an association between drugs used for the treatment of RA and the development of ILD.