Association of rheumatoid arthritis-related autoantibodies with pulmonary function test abnormalities in a rheumatoid arthritis registry

Rheumatoid arthritis and changes on spirometry by smoking status in two prospective longitudinal cohorts

OBJECTIVE

To compare longitudinal changes in spirometric measures between patients with rheumatoid arthritis (RA) and non-RA comparators.

METHODS

We analysed longitudinal data from two prospective cohorts: the UK Biobank and COPDGene. Spirometry was conducted at baseline and a second visit after 5-7 years. RA was identified based on self-report and disease-modifying antirheumatic drug use; non-RA comparators reported neither. The primary outcomes were annual changes in the per cent-predicted forced expiratory volume in 1 s (FEV1%) and per cent predicted forced vital capacity (FVC%). Statistical comparisons were performed using multivariable linear regression. The analysis was stratified based on baseline smoking status and the presence of obstructive pattern (FEV1/FVC <0.7).

RESULTS

Among participants who underwent baseline and follow-up spirometry, we identified 233 patients with RA and 37 735 non-RA comparators. Among never-smoking participants without an obstructive pattern, RA was significantly associated with more FEV1% decline (β=-0.49, p=0.04). However, in ever smokers with ≥10 pack-years, those with RA exhibited significantly less FEV1% decline than non-RA comparators (β=0.50, p=0.02). This difference was more pronounced among those with an obstructive pattern at baseline (β=1.12, p=0.01). Results were similar for FEV1/FVC decline. No difference was observed in the annual FVC% change in RA versus non-RA.

CONCLUSIONS

Smokers with RA, especially those with baseline obstructive spirometric patterns, experienced lower FEV1% and FEV1/FVC decline than non-RA comparators. Conversely, never smokers with RA had more FEV1% decline than non-RA comparators. Future studies should investigate potential treatments and the pathogenesis of obstructive lung diseases in smokers with RA.

Lung function trajectory of rheumatoid arthritis-associated interstitial lung disease

OBJECTIVES

To explore the course of lung function and RA disease activity and predictive factors for deteriorating lung function in patients with RA-interstitial lung disease (ILD).

METHODS

The Korean Rheumatoid Arthritis-Interstitial Lung Disease cohort is a multicentre, prospective observational cohort. Patients with RA-ILD were enrolled and followed up annually for 3 years for RA disease activity and ILD status assessment. Group-based modelling was used to cluster a similar predicted percentage of forced vital capacity (FVC%) patterns into trajectories.

RESULTS

This study included 140 patients who underwent at least two pulmonary function tests. Four distinctive trajectories for predicted FVC% were 'improving' [n = 11 (7.9%)], 'stable' [n = 68 (38.4%)], 'slowly declining' [n = 54 (48.6%)] and 'rapidly declining' [n = 7 (5.0%)]. Most (77.7%) patients maintained or improved to low RA disease activity. The lung function trajectory was not comparable to the RA disease activity trajectory. Age ≥70 years [relative risk (RR) 10.8 (95% CI 1.30, 89.71)] and early RA diagnosed within the preceding 2 years [RR 10.1 (95% CI 1.22, 84.2)] were associated with increased risk for rapidly declining predicted FVC%. The risk for deterioration or mortality increased in patients with a simultaneous diagnosis of RA and ILD within 24 weeks [RR 9.18 (95% CI 2.05, 41.0)] and the extent of lung involvement [RR 3.28 (95% CI 1.12, 9.60)].

CONCLUSION

Most patients with RA-ILD experienced stable or slowly declining lung function. In 5% of patients, predicted FVC% deteriorated rapidly, especially in older adults with early RA. The lung function trajectory was not comparable to the RA disease activity trajectory.

Lung function data of North-African patients with rheumatoid arthritis: a comparative study between anti-citrullinated peptides antibodies positive and negative patients

INTRODUCTION

Although lung damages are among the leading causes of death from Rheumatoid Arthritis (RA), few studies have assessed the spirometric and plethysmographic data and profile of patients with RA, particularly those with Anti-Citrullinated Peptides Antibodies Positive (ACPA+).

AIM

To compare the spirometric and plethysmographic data and profile of RA patients ACPA+ and ACPA-.

METHODS

This comparative pilot study was performed over a two-year period (2018-2019) in Algiers (Algeria). The study included two groups of RA non-smoker patients: 26 ACPA+ and 33 ACPA-.RA was diagnosed according to the ACR/EULAR 2010 RA classification criteria. Spirometry and plethysmography were performed. The following definitions were applied: Obstructive Ventilatory Impairment (OVI): FEV1/FVC z-score < -1.645; Restrictive Ventilatory Impairment (RVI): Total Lung Capacity (TLC) z-score< -1.645; Mixed Ventilatory Impairment (MVI): FEV1/FVC z-score < -1.645 and TLC z-score < -1.645; lung- hyperinflation: residual volume z-score > +1.645; Nonspecific Ventilatory Impairment (NSVI): FEV1z-score < -1.645, FVC z-score < -1.645, FEV1 /FVC z-score ≥ -1.645, and TLC z-score ≥ -1.645.

RESULTS

The ACPA-group was older than the ACPA+ one by ~ 10 years (63±13 vs. 53±12 years, p=0.0025; respectively). The ACPA+ and ACPA-groups included comparative percentages of patients having RVI, MVI, and NSVI (23.1 vs. 45.5%, p=0.0745; 3.8 vs. 3.0%, p=0.8654; and 7.7 vs. 6.1%, p=0.8086; respectively). Compared to the ACPA- group, the ACPA+ group included a higher percentage of patients having OVI and lung-hyperinflation (9.1 vs. 38.5%, p=0.0069; 9.1 vs. 42.3%, p=0.0029; respectively).

CONCLUSION

Compared to the ACPA-group, the ACPA+ one had more lung-hyperinflation and OVI, and comparative percentages of RVI, MVI, and NSVI.

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.

Screening for preclinical parenchymal lung disease in rheumatoid arthritis

OBJECTIVES

Pulmonary disease is a common extraarticular manifestation of RA associated with increased morbidity and mortality. No current strategies exist for screening this at-risk population for parenchymal lung disease, including emphysema and interstitial lung disease (ILD).

METHODS

RA patients without a diagnosis of ILD or chronic obstructive pulmonary disease underwent prospective and comprehensive clinical, laboratory, functional and radiological evaluations. High resolution CT (HRCT) scans were scored for preclinical emphysema and preclinical ILD and evaluated for other abnormalities.

RESULTS

Pulmonary imaging and/or functional abnormalities were identified in 78 (74%) of 106 subjects; 45% had preclinical parenchymal lung disease. These individuals were older with lower diffusion capacity but had similar smoking histories compared with no disease. Preclinical emphysema (36%), the most commonly detected abnormality, was associated with older age, higher anti-cyclic citrullinated peptide antibody titres and diffusion abnormalities. A significant proportion of preclinical emphysema occurred among never smokers (47%) with a predominantly panlobular pattern. Preclinical ILD (15%) was not associated with clinical, laboratory or functional measures.

CONCLUSION

We identified a high prevalence of undiagnosed preclinical parenchymal lung disease in RA driven primarily by isolated emphysema, suggesting that it may be a prevalent and previously unrecognized pulmonary manifestation of RA, even among never smokers. As clinical, laboratory and functional evaluations did not adequately identify preclinical parenchymal abnormalities, HRCT may be the most effective screening modality currently available for patients with RA.

Prevalence and risk factors of bronchiectasis in rheumatoid arthritis: A systematic review and meta-analysis

OBJECTIVES

We performed a systematic review and meta-analysis for the prevalence and risk factors of rheumatoid arthritis-related bronchiectasis (RA-BR).

METHODS

We queried PubMed and EMBASE databases to identify published literature related to prevalence and risk factors for RA-BR among patients with RA. Data extraction included study design, country, year, method of RA-BR detection, RA characteristics, numerator of RA-BR cases and denominator of patients with RA, and associations with RA-BR presence. We performed a meta-analysis using random or fixed effects models to estimate the prevalence of RA-BR among RA.

RESULTS

Out of a total of 253 studies, we identified 41 total studies that reported on prevalence (n = 34), risk factors (n = 5), or both (n = 2). The included studies had heterogeneous methods to identify RA-BR. Among the 36 studies reporting prevalence, 608 RA-BR cases were identified from a total of 8569 patients with RA. In the meta-analysis, the pooled overall prevalence of RA-BR among RA was 18.7% (95%CI 13.7-24.3%) using random effects and 3.8% (95%CI 3.3-4.2%) using fixed effects. Among studies that used high-resolution chest computed tomography (HRCT) imaging, the prevalence of RA-BR was 22.6% (95%CI 16.8-29.0%) using random effects. When only considering retrospective studies (n = 12), the pooled prevalence of RA-BR among RA was 15.5% (95%CI 7.5-25.5%); among prospective studies (n = 24), the pooled prevalence was 20.7% (95% CI 14.7-27.4%). Risk factors for RA-BR included older age, longer RA duration, genetics (CFTR and HLA), and undetectable circulating mannose binding lectin (MBL) as a biomarker.

CONCLUSION

In this systematic review and meta-analysis, the prevalence of RA-BR was nearly 20% among studies with HRCT imaging, suggesting that bronchiectasis may be a common extra-articular feature of RA. Relatively few factors have been associated with RA-BR. Future studies should standardize methods to identify RA-BR cases and investigate the natural history and clinical course given the relatively high prevalence among RA.

Relationship between rheumatoid arthritis and pulmonary function measures on spirometry in the UK Biobank

OBJECTIVE

We investigated the independent relationship of rheumatoid arthritis (RA) with type and severity of pulmonary patterns on spirometry compared to general population controls.

METHODS

This cross-sectional study investigated the association of RA and pulmonary function measures on spirometry among subjects who had spirometry performed for research purposes in the UK Biobank. RA cases were identified by self-report and current DMARD/glucocorticoid use. General population controls denied RA. Outcomes included continuous % predicted forced expiratory volume in 1 second (FEV₁ ) and forced vital capacity (FVC), type of spirometric pattern (restrictive or obstructive), and severity. We used multivariable regression to estimate the effects of RA cases versus controls, adjusting for age, sex, body mass index (BMI), and smoking status/pack-years.

RESULTS

Among 350,776 analyzed subjects with spirometry performed (mean age 56.3 years, 55.8% female, and 45.5% ever smokers), we identified 2,008 cases of treated RA. In multivariable analyses, RA was associated with lower % predicted FEV₁ (β -2.93, 95%CI -3.63,-2.24), % predicted FVC (β -2.08, 95%CI -2.72,-1.45), and FEV₁ /FVC (β -0.008, 95%CI -0.010,-0.005) than controls. RA was associated with restrictive (OR 1.36, 95%CI 1.21,1.52) and obstructive (OR 1.21, 95%CI 1.07,1.37) patterns independent of confounders. RA had the strongest associations for severe restrictive and obstructive patterns.

CONCLUSION

RA was associated with increased odds of restrictive and obstructive patterns, and this relationship was not explained by confounders including smoking. In addition to restrictive lung disease, clinicians should also be aware that airflow obstruction may be a pulmonary manifestation of RA.

Abdominal Obesity in Comparison with General Obesity and Risk of Developing Rheumatoid Arthritis in Women

OBJECTIVE

Being overweight or obese increases rheumatoid arthritis (RA) risk among women, particularly among those diagnosed at a younger age. Abdominal obesity may contribute to systemic inflammation more than general obesity; thus, we investigated whether abdominal obesity, compared to general obesity, predicted RA risk in 2 prospective cohorts: the Nurses' Health Study (NHS) and NHS II.

METHODS

We followed 50,682 women (1986-2014) in NHS and 47,597 women (1993-2015) in NHS II, without RA at baseline. Waist circumference (WC), BMI, health outcomes, and covariate data were collected through biennial questionnaires. Incident RA cases and serologic status were identified by chart review. We examined the associations of WC and BMI with RA risk using time-varying Cox proportional hazards models. We repeated analyses restricted to age ≤ 55 years.

RESULTS

During 28 years of follow-up, we identified 844 incident RA cases (527 NHS, 317 NHS II). Women with WC > 88 cm (35 in) had increased RA risk (HR 1.22, 95% CI 1.06-1.41). A similar association was observed for seropositive RA, which was stronger among young and middle-aged women. Further adjustment for BMI attenuated the association to null. In contrast, BMI was associated with RA (HRBMI ≥ 30 vs < 25 1.33, 95% CI 1.05-1.68) and seropositive RA, even after adjusting for WC, and, as in WC analyses, this association was stronger among young and middle-aged women.

CONCLUSION

Abdominal obesity was associated with increased RA risk, particularly for seropositive RA, among young and middle-aged women; however, it did not independently contribute to RA risk beyond general obesity.

Rheumatoid arthritis-related lung disease detected on clinical chest computed tomography imaging: Prevalence, risk factors, and impact on mortality

OBJECTIVE

We aimed to determine the real-world prevalence and investigate risk factors for rheumatoid arthritis (RA)-related lung disease on chest computed tomography (CT) imaging. We also investigated the impact of RA-related lung disease on mortality.

METHODS

We studied chest CT imaging abnormalities among RA patients. We determined the presence and type of abnormalities using the chest CT imaging radiologic report. RA-related lung disease was defined as interstitial lung disease (ILD), bronchiectasis, or pleural disease. We examined whether demographics and RA characteristics were associated with RA-related lung disease using logistic regression. RA-related lung disease and mortality was described using survival curves and Cox regression.

RESULTS

We analyzed 190 patients who had chest CT imaging performed for clinical indications. Mean age was 64.2 years (SD 11.8), 80.0% were female, and 75.3% were seropositive. RA-related lung disease was detected in 54 patients (28.4%); 30 (15.8%) had ILD, 27 (14.2%) had bronchiectasis, and 18 (9.5%) had pleural disease. RA-related lung disease was reported in both seropositive and seronegative RA (28.7% vs. 27.7%, p = 1.00). Male sex (OR 2.62, 95%CI 1.17-5.88) and current methotrexate use (OR 2.73, 95%CI 1.27-5.61 vs. not current) were associated with RA-related lung disease. Twenty-four (44.4%) patients with RA-related lung disease died during mean 7.0 years of follow-up. RA-related lung disease had HR of 5.35 (95%CI 0.72-39.9) for mortality compared to normal chest CT.

CONCLUSIONS

In this real-world study, RA-related lung disease was commonly detected on chest CT imaging regardless of RA serostatus. RA-related lung disease had high mortality, emphasizing the importance in close monitoring of these patients.

Long-term exposure to a mixture of industrial SO2, NO2, and PM2.5 and anti-citrullinated protein antibody positivity

BACKGROUND

Studies of associations between industrial air emissions and rheumatic diseases, or diseases-related serological biomarkers, are few. Moreover, previous evaluations typically studied individual (not mixed) emissions. We investigated associations between individual and combined exposures to industrial sulfur dioxide (SO₂), nitrogen dioxide (NO₂), and fine particles matter (PM_2.5) on anti-citrullinated protein antibodies (ACPA), a characteristic biomarker for rheumatoid arthritis (RA).

METHODS

Serum ACPA was determined for 7600 randomly selected CARTaGENE general population subjects in Quebec, Canada. Industrial SO₂, NO₂, and PM_2.5 concentrations, estimated by the California Puff (CALPUFF) atmospheric dispersion model, were assigned based on residential postal codes at the time of sera collection. Single-exposure logistic regressions were performed for ACPA positivity defined by 20 U/ml, 40 U/ml, and 60 U/ml thresholds, adjusting for age, sex, French Canadian origin, smoking, and family income. Associations between regional overall PM_2.5 exposure and ACPA positivity were also investigated. The associations between the combined three industrial exposures and the ACPA positivity were assessed by weighted quantile sum (WQS) regressions.

RESULTS

Significant associations between individual industrial exposures and ACPA positivity defined by the 20 U/ml threshold were seen with single-exposure logistic regression models, for industrial emissions of PM_2.5 (odds ratio, OR = 1.19, 95% confidence intervals, CI: 1.04-1.36) and SO₂ (OR = 1.03, 95% CI: 1.00-1.06), without clear associations for NO₂ (OR = 1.01, 95% CI: 0.86-1.17). Similar findings were seen for the 40 U/ml threshold, although at 60 U/ml, the results were very imprecise. The WQS model demonstrated a positive relationship between combined industrial exposures and ACPA positivity (OR = 1.36, 95% CI: 1.10-1.69 at 20 U/ml) and suggested that industrial PM_2.5 may have a closer association with ACPA positivity than the other exposures. Again, similar findings were seen with the 40 U/ml threshold, though 60 U/ml results were imprecise. No clear association between ACPA and regional overall PM_2.5 exposure was seen.

CONCLUSIONS

We noted positive associations between ACPA and industrial emissions of PM_2.5 and SO₂. Industrial PM_2.5 exposure may play a particularly important role in this regard.