Background:Interstitial lung disease (ILD) is a known extraarticular manifestation of rheumatoid arthritis (RA). Previous studies have shown variability in the prevalence of RA-ILD, as well as clinical characteristics and risk factors of RA-ILD.Objectives:To evaluate the prevalence and time to onset of ILD and compare the clinical characteristics between RA patients (pts) with or without ILD using a large US electronic medical record (EMR)-based dataset.Methods:Pts with an initial RA diagnosis (ICD-9-CM code: 714.0; ICD-10-CM codes: M05 & M06) during the study period (01JAN2009-20SEP2019) were included from the Discus Analytics JointMan database. The initial RA diagnosis date was defined as the index date. Pts with ILD were identified by ICD diagnosis codes or by provider indication in the JointMan record. Pts who developed ILD before RA were excluded from this analysis. The prevalence and time to onset of ILD were reported. Pt demographics, comorbidities, RA characteristics and disease activity scores were compared for 6 months prior to or on the index date (baseline period) for selected adult RA pts with available information.Results:Among 8,963 identified RA pts, 337 (3.8%) were diagnosed with ILD on or after RA diagnosis. The median time to ILD onset post-RA was 2.3 years, and 47% had ILD within 2 years after RA diagnosis. RA-ILD pts were significantly older than those without ILD (65.8 years vs. 59.1 years; p<0.001; Table 1). At baseline, a higher percentage of RA-ILD pts had history of chronic obstructive pulmonary disease, positive rheumatoid factor, rheumatoid nodules, erosive joint disease, positive anti-cyclic citrullinated peptide antibody, and joint swelling compared to RA-only pts (Table 2). The mean ESR and RA disease activity scores were also significantly higher for RA-ILD pts.Table 1.Patient DemographicsPatient demographicsRA-ONLY COhort(N = 5,612)RA-ild coHORT(N = 205)P-valueAge, Mean ± SD, years59.1 ± 14.265.8 ± 11.8<.001Male, N (%)1,375 (24.5%)72 (35.1%)0.001Race, N (%) White4,014 (71.5%)165 (80.5%)0.005 African American365 (6.5%)9 (4.4%)0.226 Other/Missing1,233 (22.0%)31 (15.1%)0.020Table 2.Baseline Clinical CharacteristicsClinical CharacteristicsRA-ONLY COhort(N = 3,846)RA-ild coHORT(N = 115)P-valueHistory of Chronic Obstructive Pulmonary Disease, N (%)102 (2.7%)8 (7.0%)0.006Hypertension, N (%)900 (23.4%)23 (20.0%)0.395Serious Infection, N (%)38 (1.0%)3 (2.6%)0.091Rheumatoid Factor Positive, N (%)1,388 (36.1%)69 (60.0%)<.001Joint Stiffness, N (%)1,092 (28.4%)39 (33.9%)0.197Rheumatoid Nodules, N (%)153 (4.0%)17 (14.8%)<.001Erosive Joint Disease, N (%)459 (11.9%)23 (20.0%)0.009Anti-CCP Antibody Positive, N (%)858 (22.3%)45 (39.1%)<.001Joint Swelling*, N (%)2,861 (58.0%)123 (68.0%)0.008Joint Tenderness*, N (%)3,728 (75.6%)138 (76.2%)0.851ESR**, Mean ± SD, mm/hr22.0 ± 22.630.1 ± 25.5<.001CRP**, Mean ± SD, mg/L22.5 ± 13.060.6 ± 25.00.086CDAI, Mean ± SD16.4 ± 12.318.9 ± 15.70.044DAS28-CRP, Mean ± SD2.6 ± 1.23.1 ± 1.4<.001DAS28-ESR, Mean ± SD3.3 ± 1.43.9 ± 1.5<.001SDAI, Mean ± SD20.2 ± 29.328.6 ± 40.20.048* A total of 4,929 non-ILD and 181 ILD patients had joint swelling and tenderness data.** Variables were calculated among patients who had available information.Conclusion:This large real-world RA population provides insight into the burden of ILD in RA pts. Pts with ILD had a higher proportion of comorbidities and RA-related conditions and higher RA activity. Further analysis is warranted to assess the risk factors of ILD and its prognosis.Disclosure of Interests:Joe Zhuo Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Qisu Zhang Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Keith Knapp Consultant of: In the last year, I was a paid consultant to Bristol Myers-Squibb Company., Employee of: I am a paid employee of Discus Analytics., Yuexi Wang Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Cynthia Gutierrez Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Ding He Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Lin Xie Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Sonie Lama Shareholder of: I own shares of Bristol-Myers Squibb Company., Employee of: I am a paid employee of Bristol-Myers Squibb Company., Gary Craig Consultant of: I have served as a consultant to Bristol-Myers Squibb Company., Employee of: I am a paid employee of Arthritis Northwest and VP of Discus Analytics., Speakers bureau: I am a member of the speakers bureau for Bristol-Myers Squibb Company.
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