TABLE 1

Demographic and clinical characteristics of all EPICure participants and those with sequenced samples

	Whole cohort^#				Sequenced samples^#
	EP^#		Controls	p-value	EP^#		Controls	p-value
	BPD	No BPD			BPD	No BPD
Subjects n	37	14	41		29	9	36
Age years	19.02±0.54	19.02±0.41	19.09±0.52	0.803^§	18.93±0.66	18.82±0.48	19.02±0.55	0.474^ƒ
Males	35	43	39	0.866^##	34	56	42	0.521^##
Females	65	57	61		66	44	58
Asthma diagnosis	57	21*	37	0.047^##	59	22	38	0.094^##
Current smoker	22	29	27	0.821^##	28	33	33	0.873^##
Passive smoke exposure >30 min·week⁻¹	22	29	35	0.471^##	32	22	60	0.348^##
Squamous epithelial cell %	17.4±17.7	17.9±11.9	13.8±11.1	0.573^ƒ	20.9±19.2	19.5±14.4	14.6±11.3	0.566^ƒ
Prescribed inhalers^¶	60	38	64	0.557^¶¶	62	17	50	0.239^¶¶
Prescribed bronchodilator inhalers⁺	53	25	55	0.417^¶¶	54	17	50	0.298^¶¶
Prescribed ICS	27	13	36	0.476^¶¶	31	17	33	0.883^¶¶
Antibiotic treatment in past year	7	13	30	0.397^¶¶	8	0	27	0.395^¶¶
Treated for respiratory problem in the past year	20	21	25	0.393^¶¶	22	11	28	0.556^##
FEV₁ L	2.66**±0.54	3.22±0.76	3.57±0.65	0.000^§	2.63**±0.66	3.45±0.76	3.55±0.61	0.000^§
FEV₁ z-score	−1.66**±1.09	−0.911±0.04	−0.37±0.87	0.000^§	−1.87**±1.17	−0.75±0.69	−0.32±0.89	0.000^§
Percentage change in FEV₁ with bronchodilator	7.93±6.25	7.75±7.81	5.26±5.60	0.077^§	9.52±7.77	7.19±4.91	5.50±5.85	0.058^§
F_eNO ppb	16.33±12.63	18.00±14.72	26.47±26.30	0.683^ƒ	16.50±13.98	16.89±15.34	25.57±27.71	0.830^ƒ
Eosinophils cells·µL⁻¹	181±127	164±104	229±148	0.184^ƒ	194±141	179±128	232±156	0.399^ƒ

Data are presented as mean±sd or %, unless otherwise stated. EP: extremely preterm birth; BPD: bronchopulmonary dysplasia; ICS: inhaled corticosteroids; FEV₁: forced expiratory volume in 1 s; F_eNO: exhaled nitric oxide fraction. ^#: whole cohort n=92, of which EP n=51, sequenced samples n=74, of which EP n=38; ^¶: β₂-adrenoreceptor agonists: salbutamol (Ventolin), terbutaline (Bricanyl), salmeterol (Serevent, Seretide); muscarinic receptor antagonist: ipratropium (Atrovent); leukotriene receptor antagonist: montelukast (Singulair); ICS: beclomethasone (Becotide), budesonide (Pulmicort), fluticasone (Flixotide, Seretide); ⁺: β₂-agonists and muscarinic receptor antagonists; ^§: calculated by ANOVA; ^ƒ: p-value calculated by Kruskal–Wallis test; ^##: p-value calculated by Chi-squared test; ^¶¶: p-value calculated by Fisher's exact test. *: p<0.05; **: p<0.01.