Craig, G. Examination of interstitial lung disease in patients with rheumatoid arthritis — prevalence, time to onset and clinical characteristics. Presented at EULAR 2020 Congress; June 3-6; Virtual
Craig reports consulting and speaking fees from Bristol-Myers Squibb Company, as well as employment with Arthritis Northwest and Discus Analytics.
Patients with interstitial lung disease demonstrated a higher proportion of comorbidities and rheumatoid arthritis activity, as well as rheumatoid arthritis-related conditions, according to a presenter at the EULAR 2020 Virtual Congress.
“Interstitial lung disease is a common extra-articular manifestation of RA, and is known to be associated with increased morbidity and mortality,” Gary Craig, MD, of Discus Analytics and Arthritis Northwest, both in Spokane, Washington, told attendees in the session. “Studies have shown substantial variability in the prevalence, clinical characteristics and risk factors of RA-associated ILD, or RA-ILD.”
To analyze the prevalence of, and the time-to-onset for, interstitial lung disease (ILD), and compare clinical characteristics between patients with RA with and without ILD, Craig and colleagues studied electronic medical records from a large, U.S.-based dataset. Using the Discus Analytics JointMan database, the researchers found 8,963 patients with an initial diagnosis of RA between Jan. 1, 2009, and Sept. 20, 2019.
The researchers identified patients with ILD using ICD codes, or through provider indication in the medical record. Patients who developed ILD prior to RA were excluded from the study. Information on prevalence and time-to-onset of ILD were also included in the medical records. Further, the researchers compared patients’ demographics, comorbidities, RA characteristics and disease activity scores for 6 months prior to, or on, the index date for selected adults with RA and available information.
According to Craig, the median time-to-onset for ILD following a diagnosis of RA was 2.3 years. Among the included patients, 47% developed ILD within 2 years after being diagnosed with RA. Patients with both conditions were significantly older than those without ILD (P < .001). In addition, a higher percentage of patients with both RA and ILD demonstrated a history of chronic obstructive pulmonary disease, positive rheumatoid factor, rheumatoid nodules, erosive joint disease, positive anticyclic citrullinated peptide antibody and joint swelling at baseline, compared with those with RA only.
Patients with both conditions also demonstrated significantly higher mean ESR and RA disease activity scores.
“This large, real-world study provides insight into the increased burden of disease among patients with RA-ILD vs. RA only,” Craig said. “... No correlation was found between cigarette smoking and ILD despite the higher prevalence of anti-CCP in the RA-ILD vs. RA-only group. Further analysis is warranted to assess risk factors for RA-ILD and its prognosis.”