THU0154 HIGH RESOLUTION COMPUTED TOMOGRAPHY (HRCT) OF THE LUNG IN PATIENTS WITH RHEUMATOID ARTHRITIS: PREVALENCE OF INTERSTITIAL LUNG DISEASE INVOLVEMENT AND DETERMINANTS OF ABNORMALITIES
Authors: Fausto Salaffi, Marina Carotti, Marco DI Carlo, Marika Tardella, Andrea Giovagnoni
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> Interstitial lung disease (ILD) causes significant morbidity and mortality in patients with rheumatoid arthritis (RA). An international consensus about the identification of a subgroup of RA-patients with an high risk to develop ILD is still lacking. <h3>Objectives</h3> To assess: (a) the prevalence of ILD involvement in RA on high resolution computed tomography (HRCT) scan; (b) the relationships between pulmonary function tests (PTFs), patient-centred measures and ILD, (c) the potential risk factors that contribute to ILD in RA-patients. <h3>Methods</h3> We retrospectively evaluated the data of RA patients afferent to an italian rheumatological center from 1/1/2014 to 30/6/2018. We extrapolated clinical (age, gender, age at onset the RA), laboratoristic [rheumatoid factor (RF) and anti-citrullinated protein antibodies (ACPAs)], respiratory functional data [forced vital capacity (FVC) and single-breath diffusing capacity for carbon monoxide (DLco)], patient-centred measures of dyspnea (PCMD) (modified Borg Dyspnea Index and VAS for breathing), health assessment questionnaire-disability index (HAQ-DI), and HRCT. HRCT abnormalities were scored using a conventional visual reader-based score (CoVR)(1) and a computer-aided method (CaM)(2). The relationships among the two HRCT scores, PFTs and PCMD were calculated using Pearson9s correlation. The AUC-ROC curve was calculated to determinate the discriminative performance of measures between patients with and without ILD. Multivariate regression model was used to assess the strength of association between ILD and RA features. <h3>Results</h3> 151 patients with RA were included (45 males and 106 females, mean age of 53.4 ± 7.6 years). We identified ILD in 29 of 151 patients (19.2%). Usual interstitial pneumonia was the most common pattern on HRCT. Patients with ILD were older (p&lt;0.01), their age at RA-onset and HAQ-DI were higher (respectivelly with p&lt;0.01 and p&lt;0.05) than patients without RA-ILD. RF positivity and titer were similar in the two groups, whereas ACPA positivity and titre were higher in ILD group (p=0.02). Extent and severity of ILD, total CoVR and CaM score correlated closely with DLco and PCMD (both with p&lt;0.0001) A reduced DLco was the most sensitive test to predict the presence of ILD on HRCT (AUC-ROC, 0.811±0.037). Multivariate analysis showed that older age (p&lt;0.0001), age at RA onset, (p=0.025), APCA titers (p=0.004) and smoking habit (p=0.008) were independent explanatory variables of HRCT damage. <h3>Conclusion</h3> ILD is a frequent feature of RA. RA-ILD is associated with age, age at RA-onset, smoking habit, and ACPA titer. DLco seems the most sensitive measure to predict ILD on HRCT scan, followed by PCMD. <h3>References</h3> 1Warrick JH, Bhalla M, Schabel SI, Silver RM. High resolution computed tomography in early scleroderma lung disease. J Rheumatol. 1991; 18(10):1520-8. 2Shin KE, Chung MJ, Jung MP, Choe BK, Lee KS. Quantitative computed tomographic indexes in diffuse interstitial lung disease: correlation with physiologic tests and computed tomography visual scores. J Comput Assist Tomogr. 2011; 35(2):266-27. <h3>Disclosure of Interests</h3> Fausto Salaffi Grant/research support from: Abbvie, Roche, Novartis, BMS, Pfizer, Sanofi, Speakers bureau: Abbvie, Roche, Novartis, Pfizer, Sanofi, BMS, marina carotti Speakers bureau: abbvie pfizer novartis roche bms sanofi, Marco Di Carlo: None declared, Marika Tardella: None declared, Andrea Giovagnoni: None declared