Table 1.

Types and distribution of interstitial lung disease and connective tissue disease^†

Characteristics	ILD (n=1256)					No ILD (n=2317)
	UIP 551 (44%)	NSIP 74 (6%)	OP 70 (6%)	LIP 4 (<1%)	PF-NOS 557 (44%)
CTD (n=450)	29 (9%)	35 (11%)	19 (6%)	2 (<1%)	241 (74%)	124 (5%)
RA	8 (28%)	6 (17%)	3 (16%)	0 (0%)	64 (27%)	62 (50%)
PM/DM	4 (14%)	7 (20%)	5 (26%)	0 (0%)	27 (11%)	6 (5%)
SSc	3 (10%)	6 (17%)	2 (11%)	0 (0%)	59 (24%)	13 (10%)
SLE	0 (0%)	2 (6%)	0 (0%)	1 (50%)	13 (5%)	6 (5%)
MCTD	7 (24%)	7 (20%)	2 (11%)	1 (50%)	48 (20%)	14 (11%)
Sjögren	2 (7%)	3 (9%)	1 (5%)	0 (0%)	9 (4%)	11 (9%)
UCTD	5 (17%)	4 (11%)	6 (31%)	0 (0%)	21 (9%)	12 (10%)
No CTD (n=3123)	522 (56%)	39 (4%)	51 (6%)	2 (<1%)	316 (34%)	2193 (95%)

^†ILD, interstitial lung disease; CTD, connective tissue disease; UIP, usual interstitial pneumonia; NSIP, nonspecific interstitial pneumonia; OP, organizing pneumonia; LIP, lymphoid interstitial pneumonia; PF-NOS, pulmonary fibrosis non-otherwise specified or unclassifiable; RA, rheumatoid arthritis; PM/DM, poly-/dermatomyositis; SSc, systemic sclerosis; SLE, systemic lupus erythematosus; MCTD, mixed connective tissue disease; UCTD, undifferentiated connective tissue disease