Related factors, increased mortality and causes of death in patients with rheumatoid arthritis-associated interstitial lung disease

Abstract

Objectives: Interstitial lung disease (ILD) is a life-threatening extra-articular manifestation of rheumatoid arthritis (RA). We aimed to clarify the relationship between chronic ILD with a pattern of usual interstitial pneumonia (UIP) or non-UIP and mortality in RA patients.

Methods: We retrospectively surveyed information of consecutive RA patients who visited our hospital from 2009 to 2014. The relationship between their mortality and chronic ILD (UIP or non-UIP) detected by high-resolution computed tomography was examined.

Results: Of 2702 patients enrolled, 261 (9.7%) had chronic ILD and among these 120 had a UIP pattern. At the onset of RA, the prevalence of chronic ILD was 6%. Patients with chronic ILD had a higher mortality than those without. The most frequent cause of death was pneumonia including acute exacerbation (AE) of chronic ILD. Lung cancer death was frequently identified in deceased patients with chronic ILD with a UIP pattern compared with the other decedents (p=.062). The estimated mortality of lung cancer in patients with chronic ILD with a UIP pattern was five times higher than the general population.

Conclusion: RA patients with ILD with a UIP pattern have a high mortality rate and are prone to die of AE or lung cancer.

Keywords:

• Idiopathic pulmonary fibrosis
• interstitial lung disease
• lung cancer
• rheumatoid arthritis
• usual interstitial pneumonia

Conflict of interest

T.K., A.H., A.T., K.K., S.N., H.T., H.O., T.N. and T.M. received grants from Chugai Pharmaceutical Co., Ltd. and Janssen Pharmaceutical KK. H.F. has the following conflicts, and the following funders are supported wholly or in part by the indicated pharmaceutical companies. The Japan Research Foundation for Clinical Pharmacology is run by Daiichi Sankyo, the Takeda Science Foundation is supported by an endowment from Takeda Pharmaceutical Company and the Nakatomi Foundation was established by Hisamitsu Pharmaceutical Co., Inc. The Daiwa Securities Health Foundation was established by Daiwa Securities Group Inc. and Mitsui Sumitomo Insurance Welfare Foundation was established by Mitsui Sumitomo Insurance Co., Ltd. H.F. was supported by research grants from Bristol-Myers Squibb Co. H.F. received honoraria from Ajinomoto Co., Inc., Daiichi Sankyo Co., Ltd., Dainippon Sumitomo Pharma Co., Ltd., Pfizer Japan Inc., and Takeda Pharmaceutical Company, Luminex Japan Corporation Ltd., and Ayumi Pharmaceutical Corporation. S.T. was supported by research grants from the following pharmaceutical companies: Abbott Japan Co., Ltd., Astellas Pharma Inc., Chugai Pharmaceutical Co., Ltd., Eisai Co., Ltd., Mitsubishi Tanabe Pharma Corporation, Pfizer Japan Inc., Takeda Pharmaceutical Company Limited, Teijin Pharma Limited. ST received honoraria from Asahi Kasei Pharma Corporation, Astellas Pharma Inc., AbbVie GK., Chugai Pharmaceutical Co., Ltd., Ono Pharmaceutical Co., Ltd., Mitsubishi Tanabe Pharma Corporation, and Pfizer Japan Inc. A.K. declares no financial or commercial conflict of interest.