POS0070 RHEUMATOID ARTHRITIS-ASSOCIATED ILD: SCREENING AND EVALUATION IN HIGH-RISK PATIENTS (RAISE) STUDY: PILOT DATA FOR THE POTENTIAL ROLE OF LUNG ULTRASOUND AS A SCREENING TOOL

Abstract

<p><strong>Background:</strong> Rheumatoid arthritis (RA) is a chronic inflammatory disease associated with various extra-articular manifestations, including rheumatoid arthritis-associated interstitial lung disease (RA-ILD). RA-ILD contributes to significant morbidity and is a leading cause of death in patients with RA. Detection of lung involvement is therefore important.</p><p><strong>Objectives:</strong> The Rheumatoid Arthritis-Associated ILD: Screening and Evaluation in high-risk patients (RAISE) study was performed to assess the prevalence of RA-ILD among RA patients with high risk, and to identify potential markers associated with the condition.</p><p><strong>Methods:</strong> Patients with a diagnosis of RA, who were positive for RF or anti-CCP and with long disease duration (10 years or more) were recruited consecutively from three rheumatology outpatient clinics in Hong Kong (Queen Mary Hospital, Tung Wah Hospital, and Grantham Hospital). Inclusion criteria included: 1) age greater than 18 years old, 2) fulfilment of 2010 ACR/EUALR RA classification criteria[1], 3) ability to sign written consent. Exclusion criteria include: 1) pregnancy, and 2) inability or refusal to undergo HRCT, 3) known RA-ILD prior to enrolment. Baseline demographic data were collected and the Disease Activity Score 28 (DAS28) were documented. Blood tests will include C-reactive protein (CRP), erythrocyte sedimentation rate (ESR)[2], complete blood count, liver, and renal function tests, autoantibody profile. Radiographs of the chest, and full lung function including spirometry and diffusion capacity were performed. All patients underwent high resolution computer tomography (HRCT) of the thorax and lung ultrasound.</p><p><strong>Results:</strong> A total of 80 patients were recruited from January to December 2023. The majority of patients were female (N=72, 90%) and non-smoker (N=72, 90%). The median disease duration was 18.5 years. Subclinical Interstitial lung disease was found in 16 (20%) patients in HRCT assessment. Other detected lung abnormalities included bronchiectasis (N=15, 18.8%) and abnormal lung nodules (N=5, 6.3%). One case of adenocarcinoma was found (Figure 1). Lung function parameters (including forced expiratory volume, forced vital capacity and diffusion capacity) were not predictive of the presence of subclinical ILD. The presence of rheumatoid factor and/or anti-CCP in high titre (defined as three times upper limit of normal) was associated with the presence of subclinical ILD (no ILD 79.7% vs ILD 100%, p=0.05). Lung ultrasound was performed in 12 regions for B-lines measurement. Using the presence of five B-lines as cut-off, lung ultrasound had the sensitivity of 54.5% and specificity of 87.2% for the dictation of subclinical ILD. The area under the ROC curve was 0.71 (Figure 2).</p><p><strong>Conclusion:</strong> One in three seropositive RA patients with long disease duration had subclinical lung abnormalities. Our pilot data illustrated the potential role of lung ultrasound for the screening of subclinical ILD among these patients.</p>