Table 1

Baseline patient characteristics

Derivation cohort (n=124)Validation cohort (n=66)
VariableHP cases
(n=44)
Non-HP ILD controls (n=80)p ValueHP cases
(n=22)
Non-HP ILD controls (n=44)p Value
Age, years mean (SD)59.7 (10.8)56.8 (11.1)0.3860.7 (15.4)63.1 (12.7)0.04
Male sex, n (%)13 (29.6)41 (51.3)0.026 (27.3)22 (50.0)0.11
Smoking history
 Never smoker (%)21 (47.7)37 (46.9)1.0015 (68.2)19 (43.2)0.07
 Ex-smoker (%)22 (50.0)41 (51.9)1.007 (31.8)25 (56.8)0.07
 Current smoker (%)1 (2.27)1 (1.27)1.000 (0.0)0 (0.0)n/a
Pulmonary physiology
 FVC, % predicted mean (SD)67.3 (17.4)70.3 (22.3)0.9963.0 (17.1)78.5 (20.5)0.005
 FEV1, % predicted mean (SD)72.9 (18.4)73.8 (21.5)0.7167.1 (15.5)83.6 (23.8)0.004
 FEV1/FVC mean (SD)0.82 (0.06)0.80 (0.09)0.350.83 (0.09)0.81 (0.08)0.38
Selected exposure history
 Bird (%)13 (29.6)9 (11.4)0.016 (27.3)3 (6.8)0.02
 Down (%)25 (56.8)29 (36.7)0.0313 (59.1)22 (50.0)0.49
 Mould (%)11 (25.0)13 (16.4)0.346 (27.3)10 (22.7)0.76
HRCT features
 Mosaic perfusion (%)27 (61.4)17 (21.3)<0.00110 (45.5)5 (11.4)<0.01
 Diffuse GGO predominance (%)12 (27.3)4 (5.0)<0.0014 (18.2)1 (2.3)0.02
 Fibrosis33 (75.0)62 (77.5)0.7617 (77.3)39 (88.6)0.28
 Air trapping (%)19 (44.2)12 (15.2)<0.001n/an/an/a
  • GGO, ground-glass opacity; HP, hypersensitivity pneumonitis; HRCT, high-resolution CT; ILD, interstitial lung disease.