Impact of preexisting interstitial lung disease on mortality in COVID-19 patients from the early pandemic to the delta variant epidemic: a nationwide population-based study

Table 1 Patient characteristics

	preexisting ILD n = 7,333	non-ILD n = 930,425	Absolute standardized difference
Age, years	70–74^d	40–44^d	1.52
20–49	629 (8.6)	576,627 (62.0)
50–64	1,249 (17.0)	183,839 (19.8)
65–79	3,063 (41.8)	101,498 (10.9)
80+	2,392 (32.6)	68,461 (7.4)
Sex, male	4,181 (57.0)	506,854 (54.5)	0.05
Comorbidity:
Cerebrovascular disease	1,746 (23.8)	52,304 (5.6)	0.53
Malignancy	2,354 (32.1)	40,500 (4.4)	0.77
Renal disease	1,052 (14.3)	19,586 (2.1)	0.46
Congestive heart failure	3,042 (41.5)	54,733 (5.9)	0.92
Liver disease	1963 (26.8)	75,638 (8.1)	0.51
Diabetes mellitus	3,962 (54.0)	108,140 (11.6)	1.01
LTOT before COVID-19 diagnosis	568 (7.7)	1,426 (0.2)	0.40
ILD type:
Idiopathic pulmonary fibrosis	295 (4.0)
RA-associated ILD	1,795 (24.5)
SLE-associated ILD	427 (5.8)
PM/DM-associated ILD	333 (4.5)
SSc-associated ILD	293 (4.0)
SjS-associated ILD	493 (6.7)
MPA-associated ILD	138 (1.9)
Pulmonary sarcoidosis	231 (3.2)
Pneumoconiosis	213 (2.9)
Hypersensitivity pneumonitis	69 (0.9)
Other ILD^a	4,220 (57.6)
COVID-19 treatment:
Corticosteroids^b	3,040 (41.5)	134,139 (14.4)	0.63
Steroid pulse^c	709 (9.7)	11,657 (1.3)	0.38
Tocilizumab	276 (3.8)	7,447 (0.8)	0.20
Baricitinib	169 (2.3)	11,778 (1.3)	0.08
Heparin	1,127 (15.4)	36,500 (3.9)	0.40
Respiratory support care:
Oxygen therapy	3,238 (44.2)	97,986 (10.5)	0.81
High-flow nasal cannula	439 (6.0)	10,401 (1.1)	0.27
Mechanical ventilation	505 (6.9)	13,096 (1.4)	0.28
ECMO	21 (0.3)	778 (0.1)	0.05
60-day mortality	1,039 (14.2)	15,665 (1.7)	0.48

Data are presented as median age category or number (%)
^a Langerhans cell histiocytosis, lymphangioleiomyomatosis, radiation pneumonitis, eosinophilic pneumonia, granulomatosis with polyangiitis-associated ILD, eosinophilic granulomatosis with polyangiitis-associated ILD, mixed connective tissue disease-associated ILD, idiopathic interstitial pneumonias other than idiopathic pulmonary fibrosis, and unspecified ILD
^b Corticosteroids newly administered within 60 days of COVID-19 diagnosis or corticosteroid dosage increased within 60 days of COVID-19 diagnosis in patients on corticosteroids before diagnosis
^c The use of corticosteroids equivalent to 500 mg or more of methylprednisolone at least once within 60 days of COVID-19 diagnosis
^d Median age category
DM, dermatomyositis; ILD, interstitial lung disease; ECMO, extracorporeal membrane oxygenation; LTOT, long term oxygen therapy; MPA, microscopic polyangiitis; PM, polymyositis; RA, rheumatoid arthritis; SjS, Sjogren syndrome; SLE, systemic lupus erythematosus; SSc, systemic sclerosis

ISSN: 1465-993X