TABLE 1

Baseline characteristics, patient-reported quality of life outcome comparisons, and LASSO predictor models of Chronic Respiratory Questionnaire (CRQ) domains

ParameterIPFNon-IPFp-value#
Subjects n53114
Age years71 (68–76)68 (61–75)0.006
Female sex12 (23%)56 (49%)0.001
FVC % pred71 (61–82)68 (55–85)0.642
DLCO % pred46 (38–59)50 (39–63)0.214
Ever-smoker status29 (55%)60 (53%)0.674
UIP radiological pattern on CT47 (89%)25 (22%)<0.0001
Reported symptom duration months24 (10–53)18 (8–42)0.215
6MWT distance m363 (297–385); (n=22)347 (268–469); (n=34)0.687
mMRC dyspnoea scale (0–4)2 (1–3)3 (1–3)0.147
PANAS Positive Score34 (28–37)33 (27–38)0.776
PANAS Negative Score12 (11–17)15 (12–20)0.043
PANAS ratio >2.923 (44%)30 (28%)0.042
SMAS-30 Taking Initiatives subscore (0–100)70 (60–84)68 (56–84)0.508
SMAS-30 Investment behaviour subscore (0–100)68 (56–78)64 (52–80)0.797
SMAS-30 Self-efficacy subscore (0–100)92 (84–100)92 (82–100)0.539
SMAS-30 Total (0–100)70 (59–80)68 (59–80)0.802
CRQ Dyspnoea5.8 (4.1–6.6)5.2 (3.4–6.2)0.165
CRQ Fatigue4.5 (3.5–5.3)4.0 (3.0–5.0)0.068
CRQ Emotional subscale5.3 (4.5–6.0)5.0 (4.1–5.9)0.104
CRQ Mastery5.5 (4.5–6.3)5.3 (4.0–6.3)0.179
CRQ Emotional Function (1–7)5 (4.5–6)5 (4.1–5.9)0.104
CRQ Physical score5.3 (3.9–5.7)4.7 (3.2–5.5)0.057

Data are presented as median (interquartile range) or n (%), unless otherwise stated. IPF: idiopathic pulmonary fibrosis; FVC: forced vital capacity; DLCO: diffusion capacity for carbon monoxide; UIP: usual interstitial pneumonia; CT: computed tomography; 6MWT: 6-min walk test; mMRC: modified Medical Research Council; PANAS: positive and negative affect survey; SMAS-30: self-management assessment survey 30. #: comparison between IPF and non-IPF subjects.