Association of physical inactivity and handgrip strength with non-tuberculous mycobacterial pulmonary disease

BACKGROUND

Little is known about the level of physical activity (PA) among patients with non-tuberculous mycobacterial pulmonary disease (NTM-PD), the relationship between PA levels and NTM-PD, and the relationship between handgrip strength and NTM-PD.

METHODS

We conducted a case-control study comparing the PA levels and handgrip strength of patients with NTM-PD and controls. Patients with NTM-PD were prospectively enrolled at Severance Hospital, Seoul, whereas controls were selected at a 1:2 propensity score matching from the Korea National Health and Nutrition Examination Survey conducted between 2014 and 2019. Multivariate logistic regression analysis was conducted to evaluate these relationships.

RESULTS

The total PA level in the NTM-PD group was lower than that in the control group (120.0 vs. 560.0 MET-min/week, P < 0.001). Physical inactivity was significantly associated with both NTM-PD (aOR 2.87, 95% CI 1.73-4.75) and severity of NTM-PD (aOR 3.82, 95% CI 1.61-9.05; cavity ≥1). Low handgrip strength was found to be associated with NTM-PD (aOR 2.14, 95% CI 1.14-4.02), but no significant association was observed with the severity of NTM-PD.

CONCLUSIONS

Physical inactivity was associated with both NTM-PD and NTM-PD severity, whereas low handgrip strength was associated with NTM-PD..

Body appreciation around the world: Measurement invariance of the Body Appreciation Scale-2 (BAS-2) across 65 nations, 40 languages, gender identities, and age

The Body Appreciation Scale-2 (BAS-2) is a widely used measure of a core facet of the positive body image construct. However, extant research concerning measurement invariance of the BAS-2 across a large number of nations remains limited. Here, we utilised the Body Image in Nature (BINS) dataset - with data collected between 2020 and 2022 - to assess measurement invariance of the BAS-2 across 65 nations, 40 languages, gender identities, and age groups. Multi-group confirmatory factor analysis indicated that full scalar invariance was upheld across all nations, languages, gender identities, and age groups, suggesting that the unidimensional BAS-2 model has widespread applicability. There were large differences across nations and languages in latent body appreciation, while differences across gender identities and age groups were negligible-to-small. Additionally, greater body appreciation was significantly associated with higher life satisfaction, being single (versus being married or in a committed relationship), and greater rurality (versus urbanicity). Across a subset of nations where nation-level data were available, greater body appreciation was also significantly associated with greater cultural distance from the United States and greater relative income inequality. These findings suggest that the BAS-2 likely captures a near-universal conceptualisation of the body appreciation construct, which should facilitate further cross-cultural research.

Catalytic ozonation of methylethylketone over porous Mn-Cu/HZSM-5

The catalytic ozonation of methylethylketone (MEK) was performed at the room temperature (25 °C) using the synthesized Mn and Cu-loaded zeolite (ZSM-5, SiO₂/Al₂O₃ = 80) catalysts. The ZSM-5 zeolite was used as a porous support material due to the large surface area and high capacity for adsorption of volatile organic compounds. Since Mn and Cu-loaded zeolite catalysts were effective for the catalytic ozonation of VOCs such as MEK, according to the loaded concentration of Mn and Cu, there are four types of metal loaded ZSM5 catalysts synthesized [5 wt% Mn/ZSM-5, 5 wt% Cu/ZSM-5, 5 wt% Mn-1 wt% Cu/ZSM-5 (5Mn1CuZSM), and 5 wt% Cu-1 wt% Mn/ZSM-5]. The catalytic efficiency for the removal of MEK and ozonation using the different catalysts was also studied. Based on various experimental analysis processes, the characteristics of the synthesized catalysts were explored and the removal efficiencies of MEK and O₃ together with the CO_x concentration generated from the destruction of MEK and O₃ were explored. The results for the decomposition of MEK and O₃ at the room temperature indicated that the Mn dominant ZSM-5 catalysts showed better efficiency for the conversion of MEK and O₃. The 5 wt% Mn/ZSM-5 outweighed the rest of them for the removal of MEK while the 5Mn1CuZSM showed the best catalytic reactivity for the conversion of O₃ and the CO₂ selectivity. It was ascertained that during the reaction time of catalyst and reactants of 120 min the Mn dominantly deposited bimetallic catalyst, 5Mn1CuZSM, was determined as the most effective for the removal of MEK and O₃ due to the high capability of production of Mn³⁺ species and more available adsorbed oxygen sites compared to the other catalysts. Finally, the durability measurement for the 5Mn1CuZSM catalyst was performed together with the produced CO and CO₂ concentration for 420 min.

Decent Work, Posttraumatic Stress Disorder, and Posttraumatic Growth From the Psychology of Working Perspective: A Three-Wave Study of Military Personnel

Scholarly interest in the relationship between decent work and mental health based on the Psychology of Working Theory has recently increased. This study evaluated the indirect effects of survival, social contribution, and self-determination needs satisfaction on the relationship between decent work and trauma-related mental health among military personnel. We conducted a three-wave survey over 1 year. Results showed that decent work predicted satisfaction of the three basic needs. Additionally, survival needs directly predicted posttraumatic stress disorder symptoms, while social contribution and self-determination needs directly predicted posttraumatic growth. Finally, decent work had a significant indirect effect on posttraumatic stress disorder symptoms via survival needs, whereas decent work had significant indirect effects on posttraumatic growth via social contribution and self-determination needs. Our findings suggest that the more military personnel perceive their work as decent and feel that their three basic needs are fulfilled, the more posttraumatic stress disorder symptoms diminish, and posttraumatic growth increases. We discuss the implications and need for follow-up studies.

Recurrent neural networks for dynamical systems: Applications to ordinary differential equations, collective motion, and hydrological modeling

Classical methods of solving spatiotemporal dynamical systems include statistical approaches such as autoregressive integrated moving average, which assume linear and stationary relationships between systems' previous outputs. Development and implementation of linear methods are relatively simple, but they often do not capture non-linear relationships in the data. Thus, artificial neural networks (ANNs) are receiving attention from researchers in analyzing and forecasting dynamical systems. Recurrent neural networks (RNNs), derived from feed-forward ANNs, use internal memory to process variable-length sequences of inputs. This allows RNNs to be applicable for finding solutions for a vast variety of problems in spatiotemporal dynamical systems. Thus, in this paper, we utilize RNNs to treat some specific issues associated with dynamical systems. Specifically, we analyze the performance of RNNs applied to three tasks: reconstruction of correct Lorenz solutions for a system with a formulation error, reconstruction of corrupted collective motion trajectories, and forecasting of streamflow time series possessing spikes, representing three fields, namely, ordinary differential equations, collective motion, and hydrological modeling, respectively. We train and test RNNs uniquely in each task to demonstrate the broad applicability of RNNs in the reconstruction and forecasting the dynamics of dynamical systems.

Search for 70 μeV Dark Photon Dark Matter with a Dielectrically Loaded Multiwavelength Microwave Cavity

Microwave cavities have been deployed to search for bosonic dark matter candidates with masses of a few μeV. However, the sensitivity of these cavity detectors is limited by their volume, and the traditionally employed half-wavelength cavities suffer from a significant volume reduction at higher masses. Axion dark matter experiment (ADMX)-Orpheus mitigates this issue by operating a tunable, dielectrically loaded cavity at a higher-order mode, which allows the detection volume to remain large. The ADMX-Orpheus inaugural run excludes dark photon dark matter with kinetic mixing angle χ>10^{-13} between 65.5  μeV (15.8  GHz) and 69.3  μeV (16.8  GHz), marking the highest-frequency tunable microwave cavity dark matter search to date.

Effects of early recurrence and extra-PV triggers on long-term recurrence after catheter ablation for atrial fibrillation

Background

Although early recurrence (ER) within 3 months after atrial fibrillation (AF) catheter ablation (AFCA) was recently reported to be a reliable predictor of late recurrence (LR), the mechanism is not clear.

Purpose

We explored the characteristics of patients with ER and compared the long-term late recurrence (LR) pattern depending on the existence of extra-pulmonary vein trigger (ExPV-trigger).

Methods

Among 3643 patients who underwent de novo AFCA, we included 1249 patients (59.2±11.0 years old, 31.3% persistent AF) who underwent isoproterenol provocation and regular follow-up over three years after AFCA. We evaluated the risk factors for ER and compared the patients with ER alone (10.1%), LR alone (16.6%), and ER+LR (15.9%), and the outcome of repeat procedure.

Results

Overall ER (ER alone and ER+LR) was independently associated with persistent AF (OR 1.58 [1.16–2.14], p=0.003), extra-PV triggers (OR 2.80 [1.90–4.13], p&lt;0.001), and empirical extra-PV ablation (OR 1.54 [1.15–2.07], p=0.004). Overall LR (LR alone and ER+LR) risk was significantly higher in the ER with ExPV-trigger group than in ER without ExPV-trigger or no ER groups (Log-rank p&lt;0.001). The rhythm outcome of the second procedure did not differ between ER+LR and LR alone groups (Log-rank p=0.160), but was worse in the ER+LR ExPV-trigger than in ER+LR without ExPV-trigger or LR alone groups (Log-rank p=0.005).

Conclusion

ER was independently associated with LR after de novo AFCA. ExPV-trigger played crucial roles in ER and LR after de novo AFCA and worse rhythm outcome after redo AFCA.

Funding Acknowledgement

Type of funding sources: None.

External validation of the biomarker based ABCD score in atrial fibrillation patients with a non gender CHA2DS2 VASc score 0 to 1, A Korean multicenter retrospective cohort

Background

Patients with low to intermediate risk atrial fibrillation (AF), defined as non-gender CHA2DS2-VASc score of 0–1, are still at risk of stroke. This study verified the usefulness of ABCD score (Age [≥60 years], B-type natriuretic peptide [BNP] or N-terminal pro-BNP [≥300 pg/ml], Creatinine clearance [&lt;50 ml/min/1.73 m2], and Dimension of the left atrium [≥45 mm]) for stroke risk stratification in non-gender CHA2DS2-VASc score 0–1.

Methods

This multi-center cohort study retrospectively analyzed AF patients with non-gender CHA2DS2-VASc score 0–1. The primary endpoint was the incidence of stroke with or without anti-thrombotic treatment (ATT). An ABCD score was also validated.

Results

Overall, 2694 patients (56.3±9.5 years; female, 726 [26.9%]) were followed-up for 4.0±2.8 years. The overall stroke rate was 0.84/100 person-years (P-Y), stratified as follows: 0.46/100P-Y for an ABCD score 0; 1.02/100P-Y for an ABCD score≥1. The ABCD score was superior to the non-gender CHA2DS2-VASc score in stroke risk stratification (C-index=0.618, P=0.015; net reclassification improvement=0.576, P=0.040; integrated differential improvement=0.033, P=0.066). ATT was prescribed in 2353 patients (86.5%), and the stroke rate was significantly lower in patients receiving non-vitamin K antagonist oral anticoagulant (NOAC) therapy and an ABCD score≥1 than in those without ATT (0.44/100P-Y versus 1.55/100 P-Y; hazard ratio=0.26, 95% confidence interval 0.11–0.63, P=0.003).

Conclusion

The biomarker-based ABCD score demonstrated improved stroke risk stratification in AF patients with non-gender CHA2DS2-VASc score 0–1. Furthermore, NOAC with an ABCD score≥1 was associated with significantly lower stroke rate in AF patients with a non-gender CHA2DS2-VASc score 0–1.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Korean Disease Control and Prevention Agency

Electro-optic sampling based characterization of broad-band high efficiency THz-FEL

Extremely high beam-to-radiation energy conversion efficiencies can be obtained in a THz FEL using a strongly tapered helical undulator at the zero-slippage resonant condition, where a circular waveguide is used to match the radiation group velocity to the electron beam longitudinal velocity. In this paper we report on the first electro-optic sampling (EOS) based measurements of the broadband THz FEL radiation pulses emitted in this regime. The THz field waveforms are reconstructed in the spatial and temporal domains using multi-shot and single-shot EOS schemes respectively. The measurements are performed varying the input electron beam energy in the undulator providing insights on the complex dynamics in a waveguide FEL.

Regional and annual patterns in respiratory virus co-infection etiologies and antibiotic prescriptions for pediatric mycoplasma pneumoniae pneumonia

OBJECTIVE

Mycoplasma pneumoniae (M. pneumoniae) pneumonia is the second-most common cause of community-acquired pneumonia (CAP). This study aimed at investigating into the prevalence of macrolide-resistant M. pneumoniae (MRMP) with respiratory virus co-infection and the antibiotic prescriptions in children with CAP in four provinces in Korea, and to assess the variations in the findings across regions and throughout the year.

PATIENTS AND METHODS

This prospective study was conducted in 29 hospitals in Korea between July 2018 and June 2020. Among the enrolled 1,063 children with CAP, all 451 patients with M. pneumoniae underwent PCR assays of M. pneumoniae and respiratory viruses, and the presence of point mutations of residues 2063 and 2064 was evaluated.

RESULTS

Gwangju-Honam (88.6%) showed the highest prevalence of MRMP pneumonia, while Daejeon-Chungcheong (71.3%) showed the lowest, although the differences in prevalence were not significant (p=0.074). Co-infection of M. pneumoniae pneumonia and respiratory virus was observed in 206 patients (45.4%), and rhinovirus co-infection (101 children; 22.2%) was the most frequent. The prevalence of MRMP pneumonia with respiratory virus co-infection and the antibiotic prescriptions differed significantly among the four provinces (p < 0.05). The monthly rate of MRMP pneumonia cases among all cases of M. pneumoniae pneumonia and tetracycline or quinolone prescriptions did not differ significantly among the four regions (trend p > 0.05) during the study period.

CONCLUSIONS

The prevalence of M. pneumoniae pneumonia with virus co-infection and antibiotic prescriptions could differ according to region, although the MRMP pneumonia rate showed no difference within Korea.

POS0030 CLINICAL AND GENETIC FACTORS ASSOCIATED WITH RADIOGRAPHIC PROGRESSION IN PATIENTS WITH ANKYLOSING SPONDYLITIS

Background

Ankylosing spondylitis (AS) is a heritable inflammatory disease eventually leading to spinal fusion 1. Severity of structural damage is highly variable, some patients develop almost no change in spinal structure for long disease duration, whereas others have total ankylosis even in the early stage of disease.

Objectives

To identify clinical and genetic factors associated with severe radiographic damage in patients with AS.

Methods

We newly generated genome-wide variant data (833K, KoreanChip) of 444 AS patients. The severity of radiographic damage was assessed using the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS). To identify clinical and genetic factors associated with severe radiographic damage, multiple linear regression analyses were performed. Human AS osteoprogenitor cells were used for functional validation. Pathway analysis was also conducted.

Results

A total 444 AS patients (male 90.3%) were enrolled. The median mSASSS at baseline was 7.7 (5.5-16.8). The patients were observed for 9.6 (7.9-11.3) years. Within this period, the median mSASSS score increased to 14.0 (7.0-36.8). The most influential clinical factor of final mSASSS was baseline mSASSS (β = 0.818, p < 0.001). Peripheral joint involvement was associated with decreased possibility of severe radiographic damage (β = -0.221, p < 0.001). Eye involvement, longer follow up duration, and increased age at enrollment were associated with increased final mSASSS (β = 0.165, p < 0.001; β = 0.039, p < 0.001; β = 0.010, p = 0.002, respectively). Ryanodine receptor 3 (RYR3) gene was associated with severe radiographic damage (β = 1.105, p = 1.97x10-06). Treatment with Rhodamine B, a ligand of RYR3, induced extracellular matrix mineralization of AS osteoprogenitors in vitro. For the pathway analysis, PI3K-Akt signaling pathway and focal adhesion pathway were associated with severe radiographic damage in AS.

Conclusion

This study identified clinical and genetic factors that contributed to better understanding of the pathogenesis and biology associated with radiographic damage in AS.

References

[1]Li Z, Brown MA. Progress of genome-wide association studies of ankylosing spondylitis. Clinical & Translational Immunology. 2017;6(12):e163.

Disclosure of Interests

None declared

COVID-19 susceptibility and clinical outcomes in autoimmune inflammatory rheumatic diseases (AIRDs): a systematic review and meta-analysis

OBJECTIVE

This meta-analysis aims to assess the susceptibility to and clinical outcomes of COVID-19 in autoimmune inflammatory rheumatic disease (AIRD) and following AIRD drug use.

MATERIALS AND METHODS

We included observational and case-controlled studies assessing susceptibility and clinical outcomes of COVID-19 in patients with AIRD as well as the clinical outcomes of COVID-19 with or without use of steroids and conventional synthetic disease-modifying antirheumatic drugs (csDMARDs).

RESULTS

Meta-analysis including three studies showed that patients with AIRD are not more susceptible to COVID-19 compared to patients without AIRD or the general population (OR: 1.11, 95% CI: 0.58 to 2.14). Incidence of severe outcomes of COVID-19 (OR: 1.34, 95% CI: 0.76 to 2.35) and COVID-19 related death (OR: 1.21, 95% CI: 0.68 to 2.16) also did not show significant difference. The clinical outcomes of COVID-19 among AIRD patients with and without csDMARD or steroid showed that both use of steroid (OR: 1.69, 95% CI: 0.96 to 2.98) or csDMARD (OR: 1.35, 95% CI: 0.63 to 3.08) had no effect on clinical outcomes of COVID-19.

CONCLUSIONS

AIRD does not increase susceptibility to COVID-19, not affecting the clinical outcome of COVID-19. Similarly, the use of steroids or csDMARDs for AIRD does not worsen the clinical outcome.

The Multidimensional Workaholism Scale in a Korean Population: A Cross-Cultural Validation Study

This study aimed to provide a reliable and valid measure of workaholism for Korean workers. We translated the Multidimensional Workaholism Scale (MWS) into Korean and validated it with a sample of 1020 full-time Korean employees. An exploratory factor analysis revealed a four-factor solution (Study 1; N = 524), and a confirmatory analysis further demonstrated good model fit of the four-factor structure (Study 2; N = 496). The scale’s concurrent and construct validity was supported by positive correlations with other existing measures of workaholism, emotional exhaustion, and work–family conflict (WFC) and by a negative correlation with psychological detachment. Moreover, the MWS demonstrated a moderate association with work engagement, but no significant association with job satisfaction. It further showed significant incremental validity in predicting emotional exhaustion and WFC. The findings support the Korean MWS version’s reliability and validity for measuring workaholism among Korean employees. Theoretical implications for the workaholism literature and practical implications for corporate counselors and human resource practitioners are discussed.

Re-evaluation of the prognostic significance of oropharyngeal dysphagia in idiopathic inflammatory myopathies

OBJECTIVE

To investigate the prognostic significance of videofluorographic swallowing study (VFSS)-confirmed oropharyngeal dysphagia in idiopathic inflammatory myopathies (IIMs).

METHOD

We reviewed the medical records of patients who were diagnosed with IIM between 2009 and 2020 at Seoul St Mary's Hospital. All oropharyngeal dysphagia cases were limited to VFSS-confirmed dysphagia found during the initial diagnostic work-up for IIM. We described the findings on VFSS and the course of the dysphagic symptoms. Logistic regression and survival analyses were performed to evaluate the risk of pneumonia and mortality, respectively.

RESULTS

We found 88 patients with IIM who met the criteria. Among them, 17 patients (19%) had oropharyngeal dysphagia. Except for two cases lost to follow-up and one deceased case, all of the patients with dysphagia (14 of 14) had swallowing function restored within 6 months. The risk of pneumonia within 3 months from the diagnosis of IIM was significant [odds ratio = 4.49, 95% confidence interval (CI) 1.07-18.88]. The median follow-up duration was 34 and 27 months for the groups without and with dysphagia, respectively. The survival analysis failed to demonstrate that the presence of oropharyngeal dysphagia increased the risk of death (hazard ratio = 0.77, 95% CI: 0.085-7.00).

CONCLUSIONS

Oropharyngeal dysphagia found at the initial diagnosis of IIM improved within 3-6 months in nearly all cases. Furthermore, IIM patients who had oropharyngeal dysphagia at the initial diagnosis of IIM were not likely to have shorter survival, even if the risk of pneumonia was increased in the short term.

POS0555 THE NATURAL COURSE OF RHEUMATOID ARTHRITIS-ASSOCIATED INTERSTITIAL LUNG DISEASE FOCUSING ON LUNG PHYSIOLOGY: A PROSPECTIVE OBSERVATIONAL COHORT STUDY (PART 1)

Background:

Interstitial lung disease (ILD) is a severe extra-articular manifestation of rheumatoid arthritis (RA). However, there are few prospective studies for the natural course of lung physiology in most patients with RA-ILD.

Objectives:

To assess the natural course of lung physiology of RA-ILD and the relation between arthritis activity and pulmonary physiology in patients with RA-ILD.

Methods:

The KOrean Rheumatoid Arthritis ILd (KORAIL) cohort is the prospective observational cohort and aims to investigate the natural course of RAILD. Based on either 1987 or 2020 ACR criteria, patients diagnosed with RA and ILD based on CT scan were recruited from six tertiary medical hospitals in Korea since January 2015. RA disease activity was assessed using swollen and tender joint count by treating physician, inflammatory markers including CRP and ESR, and patient’s global assessment annually. Pulmonary function tests (PFT), including FVC, FEV1, DLCO, and chest CT scan, were conducted annually.

Results:

We analyzed 163 patients at baseline (V1), 141 at 1-year (V2), 122 at 2-year (V3), and 88 at 3-year follow-up (V4). The mean (±SD) duration since RA diagnosis and since ILD diagnosis was 7.6±8.0 and 2.7±3.1 years, respectively. The female to male ratio was about 2:1, and 58.9% of patients (n=96) were 65 years old or older. Only two patients were negative for RF and anti-CCP; 98.7% of patients (n=161/163) were positive for RF (n=143, 87.7%) or anti-CCP antibody (n=154, 94.5%). At enrollment, one-hundred-nine patients (66.9%) had FVC ≥80 % of predicted. Twenty-five patients (15.3%) showed FEV1/FVC≥0.7, of which seventeen patients, only ten percent of a total cohort (10.4%), had FVC ≥80% of predicted, which corresponds to the obstructive pattern. Proportion of patients showed a ≥10-point decline from the enrollment in FVC of the predicted value were around 10% at every year (Table 1). The proportion of patients with a relative decline of ≥10% from the enrollment in FVC predicted was increased every year because of cumulation. The proportion of patients with a relative decline of ≥10% from the previous visit in FVC predicted was also around 10-15% every year. Proportions of patients with 55% or more DLco % pred. has been decreased annually; 78.5% (n=128/158) at V1, 72.9% (n=105/139) at V2, 68.7% (n=90/117) at V3, and 56.6% (n=56/85) at V4. Patients with a relative decline of ≥10% from the enrollment in DLco predicted was 38 (27.5 %) at V2 and 37 (31.9%) at V3. Patients with a relative decline of ≥10% from the previous visit in DLco predicted was 29 (25.2%) at V3. Of note, thirty patients (21.7%) showed a relative 10% or more increase from enrollment in DLco predicted at V2, and so did 30 patients (25.9%) at V3.

Table 1.

The analysis of forced vital capacity (FVC) in KORIL cohort

V1 (enrollment)V2 (1-year)V3 (2-year)V4 (3-year)FVC (mL), mean±SD2549.5 ± 743.32479.5±764.42435.8 ± 742.82405.7 ± 731.2FVC % of predicted, mean±SD84.70 ± 16.7484.7±18.184.3 ± 17.683.1 ± 19.1Rate of FVC decline, mL·year-1 (95% CI)--14 (-49, 21)-62 (-104, -21)-A 10-point decline from V1 in predicted FVC value, n (%)-10 (7.1)16 (13.3)8 (9.4)Relative decline of 10% from V1 in predicted FVC value, n (%)-17 (12.1)23 (18.9)17 (19.3)Relative decline of 10% from the previous visit in predicted FVC value, n (%)-17 (12.1)17 (14.2)13 (15.3)

Conclusion:

Annually, about 10-15% of patients experience a relative ≥10% decline from the previous visit in FVC predicted value in RA-ILD.

Acknowledgements:

This work was supported by the Korea Health Technology R&D Project through the Korea Health Industry Development Institute, funded by the Ministry of Health and Welfare, Republic of Korea (grant no.HI14C1277).

Disclosure of Interests:

None declared

POS0563 THE NATURAL COURSE OF RHEUMATOID ARTHRITIS-ASSOCIATED INTERSTITIAL LUNG DISEASE FOCUSING ON LUNG PHYSIOLOGY AND DISEASE ACTIVITY: A PROSPECTIVE COHORT STUDY (PART 2)

Background:

Interstitial lung disease (ILD) is a severe extra-articular manifestation of rheumatoid arthritis (RA). However, the effect of RA disease activity on the course of ILD is not yet known.

Objectives:

To assess the natural course of lung physiology of RA-ILD and the relation between arthritis activity and pulmonary physiology in patients with RA-ILD.

Methods:

The Korean Rheumatoid Arthritis ILd (KORAIL) cohort is the prospective observational cohort and aims to investigate the natural course of RAILD. Based on either 1987 or 2020 ACR criteria, patients diagnosed with RA and ILD based on CT scan were recruited from six tertiary medical hospitals in Korea since January 2015. RA disease activity was assessed using disease activity (DAS)28-ESR and CRP, annually. Pulmonary function tests (PFT), including FVC and DLCO were conducted annually. According to the transition of DAS28-ESR status, we classified patients into four groups: Group A. persistent remission or low disease activity, Group B. improvement, Group C. worsening, Group D. persistent moderate to high disease activity.

Results:

We analyzed 143 patients who completed a 2-year follow-up (visit 2) or had died with available PFT results at least twice. Mean duration since RA diagnosis and since ILD diagnosis was 7.6±8.0 and 2.7±3.1 years, respectively. Twenty-four patients were Group A, 33 Group B, 10 Group C and 30 Group D. The mean of FVC (mL) and % of the predicted value in FVC was significantly lower in Group D than in other groups (Table 1). The annual rate of decline in FVC was -42 (95% CI -93~10) mL·year-1 in Group B while -113 (95% CI -206~-21) mL·year-1 in Group C (Figure 1A). The annual decline rate in Group C was further exaggerated in patients with ≥ 80% of FVC predicted (-141, 95% CI -251~-32 mL·year-1). During two years of follow-up, patients ever experienced a relative decline of ≥10% from the enrollment in FVC predicted was 27.3%(n-9/33) in Group B whereas 30.0% (3/10) in Group C. The annual rate of decline in % of DLco predicted value was also the largest in Group C (-4.6 %·year-1, 95%CI -8.5~-0.7), which further exaggerated in patients with ≥ 80% of FVC predicted (-4.9%·year-1, 95 %CI -8.3~-1.5, Figure 1B). Of note, about half of patients with maintained not only low disease activity (Group A) but also moderate to severe disease activity (Group D) improved in DLco at least 10% or more from the enrollment of DLco predicted value (Group A: 54.2%, n=13/24, Group D: 46.7%, n=14/30).

Conclusion:

RA disease activity is associated with the change of lung physiology in patients with RA-ILD; worsening disease activity associated with a further decrease of annual change in FVC and maintaining low disease activity associated with a further increase of annual change in % of DLco predicted value.

Table 1.

The analysis of forced vital capacity (FVC) according to disease activity transition group.

Group AGroup BGroup CGroup DFVC (mL), mean±SD2810.0±771.12528.8±735.32801.0±952.72048.3±575.7FVC % of predicted, mean±SD87.5±14.586.5±16.693.0±15.677.2±17.3Rate of FVC decline, mL·year-1 (95% CI)-52 (-112,7)-42 (-93,10)-113 (-206, -21)1 (-52, 54)A 10-point decline from V1 in predicted FVC value, n (%)29 (20.3)6 (25.0)6 (18.2)3 (30.0)Relative decline of 10% from the enrollment in predicted FVC value, n (%)35 (24.5)5 (20.8)9 (27.3)3 (30.0)Figure 1.

The annual change of pulmonary physiology according to disease activity transition group.

Acknowledgements:

This work was supported by the Korea Health Technology R&D Project through the Korea Health Industry Development Institute, funded by the Ministry of Health and Welfare, Republic of Korea (grant no.HI14C1277).

Disclosure of Interests:

None declared