{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T12:05:52Z","timestamp":1784721952333,"version":"3.55.0"},"reference-count":19,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T00:00:00Z","timestamp":1784678400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Adv. Respir. Med.","ARM"],"abstract":"<jats:p>Introduction: Patients with rheumatoid arthritis (RA) have higher risk for pneumonia, interstitial lung disease (ILD) and pulmonary fibrosis (PF). However, the association between an ICD-10-coded pneumonia event (CPE) and the incidence of ILD or PF in the RA population remains unclear. Methods: We conducted a retrospective cohort study using the TriNetX database. Patients with ICD-10 for RA aged 50 or older who had a CPE within one year of RA diagnosis (CPE cohort, n = 4553) were matched 1:1 by propensity score for key factors, including demographics, comorbidities (i.e., COPD), and medication use (DMARDs, corticosteroids) to RA patients without a CPE (Control cohort, n = 4553). Cox proportional hazard models assessed the incidence of a composite ILD outcome, PF, and secondary complications over a 4-year follow-up after the index event defined as 1-year after RA diagnosis for both cohorts. Results: The CPE cohort showed an increased risk for all outcomes. Patients with CPE had a 2.48-fold increased risk for PF (HR = 2.48; 95% CI, 1.78\u20133.45; p &lt; 0.01) and a 2.87-fold increased risk for the composite ILD outcome (HR = 2.87; 95% CI, 2.18\u20133.80; p &lt; 0.01). The risk of rheumatoid lung disease was 4.15 times higher (HR = 4.15; 95% CI, 2.30\u20137.50; p &lt; 0.01). Furthermore, the CPE group had a higher risk for all-cause mortality (HR = 1.82; 95% CI, 1.58\u20132.09; p &lt; 0.01). Conclusions: The CPE within one year of RA diagnosis is associated with an increase in subsequent ILD-coded outcomes. While this retrospective design cannot establish causality, an unspecified pneumonia code in early RA may represent an early clinical manifestation of unrecognized ILD, serving as a high-risk marker that warrants pulmonary surveillance.<\/jats:p>","DOI":"10.3390\/arm94040049","type":"journal-article","created":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T10:48:28Z","timestamp":1784717308000},"page":"49","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Association of ICD-10-Coded Pneumonia Events with Interstitial Lung Disease Outcomes in Patients with Rheumatoid Arthritis: A Large Database Retrospective Cohort"],"prefix":"10.3390","volume":"94","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-6831-9912","authenticated-orcid":false,"given":"Esteban","family":"Kosak Lopez","sequence":"first","affiliation":[{"name":"Medicine Department, Jefferson Einstein Philadelphia Hospital, Philadelphia, PA 19141, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0612-0033","authenticated-orcid":false,"given":"Luis","family":"Rodriguez Don\u00eds","sequence":"additional","affiliation":[{"name":"Instituto de Biomedicina, Universidad Central de Venezuela, Caracas 1051, Venezuela"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1454-4354","authenticated-orcid":false,"given":"Justin","family":"Lam","sequence":"additional","affiliation":[{"name":"Medicine Department, Jefferson Einstein Philadelphia Hospital, Philadelphia, PA 19141, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew","family":"Geller","sequence":"additional","affiliation":[{"name":"Medicine Department, Jefferson Einstein Philadelphia Hospital, Philadelphia, PA 19141, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raul","family":"Leguizamon","sequence":"additional","affiliation":[{"name":"Medicine Department, Jefferson Einstein Philadelphia Hospital, Philadelphia, PA 19141, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Vera Ricaurte","sequence":"additional","affiliation":[{"name":"Medicine Department, Jefferson Einstein Philadelphia Hospital, Philadelphia, PA 19141, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9155-919X","authenticated-orcid":false,"given":"Priscilla","family":"Nethala","sequence":"additional","affiliation":[{"name":"Medicine Department, Jefferson Einstein Philadelphia Hospital, Philadelphia, PA 19141, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0765-101X","authenticated-orcid":false,"given":"Maria","family":"Planchart Ferretto","sequence":"additional","affiliation":[{"name":"Medicine Department, Jefferson Einstein Philadelphia Hospital, Philadelphia, PA 19141, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-4997-8022","authenticated-orcid":false,"given":"Maria Laura","family":"Fernandez-Wever","sequence":"additional","affiliation":[{"name":"Pulmonary and Critical Care Division, Brigham and Women\u2019s Hospital, Boston, MA 02115, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5688-9692","authenticated-orcid":false,"given":"Jose M.","family":"Martinez-Manzano","sequence":"additional","affiliation":[{"name":"Pulmonary and Critical Care Division, Brigham and Women\u2019s Hospital, Boston, MA 02115, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Enrique","family":"Pacheco","sequence":"additional","affiliation":[{"name":"Pulmonary and Critical Care Division, Jefferson Einstein Philadelphia Hospital, Philadelphia, PA 19141, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shahrzad","family":"Abdollahi","sequence":"additional","affiliation":[{"name":"Rheumatology Division, Jefferson Einstein Philadelphia Hospital, Philadelphia, PA 19141, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1007\/s00296-025-05789-4","article-title":"The Global Prevalence of Interstitial Lung Disease in Patients with Rheumatoid Arthritis: A Systematic Review and Meta-Analysis","volume":"45","author":"Prasanna","year":"2025","journal-title":"Rheumatol. 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