Annual variation rate of KL-6 for predicting acute exacerbation in patients with rheumatoid arthritis-associated interstitial lung disease. Issue 6 (2nd November 2021)

• Record Type: Journal Article
• Authors: Tanaka, Nozomi; Nishimura, Keisuke; Waki, Daisuke; Kadoba, Keiichiro; Murabe, Hiroyuki; Yokota, Toshihiko
• Is Part Of: Modern rheumatology. Volume 31:Issue 6(2021)
• Page Start: 1100
• Page End: 1106
• Publication Date: 2021-11-02
• Subjects: Acute exacerbation -- interstitial lung disease -- KL-6 -- rheumatoid arthritis; Rheumatology -- Periodicals; 616.723005
• DOI: 10.1080/14397595.2021.1879346
• Languages: English
• ISSNs: 1439-7595

Abstract

Abstract: Objectives: This study evaluated the prognostic factors for acute exacerbation (AE), including sequential changes in Krebs von den Lungen-6 (KL-6) levels, in rheumatoid arthritis-associated interstitial lung disease (RA-ILD) patients. Methods: This was a retrospective observational study. We reviewed 125 patients diagnosed with RA-ILD between 2010 and 2019. We defined ΔKL-6 as the annual variation rate of KL-6 one visit before AE onset (or the last visit). The Cox regression analysis was used for evaluating significant variables associated with AE. We analysed the overall survival and respiratory-related death-free survival. Results: Thirty-three patients (26.4%) developed AE during the observation period. The univariate analysis revealed that KL-6 levels at RA-ILD diagnosis [hazard ratio (HR), 1.11; 95% confidence interval (CI), 1.05–1.15; p < .01) and ΔKL-6 (HR: 3.69; 95% CI: −1.36 to 7.96; p = .01] were significantly associated with AE. ΔKL-6 was an independent prognostic factor for AE in the multivariate analysis (HR: 3.37; 95% CI: −1.16 to 8.87; p = .03). Patients with AE had a significantly higher overall mortality rate ( p = .02) and respiratory-related mortality rate ( p < .01) than those without AE. Conclusion: ΔKL-6 can be a prognostic marker for detecting AE in RA-ILD patients.