Table 2.

Associations of Asthma–Lung Function Groups with Circulating Club Cell Secretory Protein from Childhood to Adult Life

Group	Z-Score Circulating CC16
	TCRS Years 6–36			BAMSE Years 8–24			MAAS Years 5–18			Overall
	n/N = 626/2,705			n/N = 1,861/2,694			n/N = 637/1,479			n/N = 3,124/6,878
	n	Coefficient (95% CI)	P Value	n	Coefficient (95% CI)	P Value	n	Coefficient (95% CI)	P Value	n	Coefficient (95% CI)	P Value
Group 1: Normal	472	ref		1,498	ref		498	ref		2,468	ref
Group 2: Low lung function only	34	−0.39 (−0.67, −0.10)	0.008	154	−0.11 (−0.26, 0.04)	0.158	38	−0.27 (−0.56, 0.02)	0.073	226	−0.19 (−0.31, −0.07)	0.003
Group 3: Asthma with frequent symptoms only	92	−0.34 (−0.52, −0.16)	0.0003	175	−0.16 (−0.30, −0.02)	0.030	73	−0.29 (−0.51, −0.07)	0.009	340	−0.24 (−0.34, −0.14)	<0.0001
Group 4: Asthma with frequent symptoms and low lung function	28	−0.36 (−0.67, −0.05)	0.023	34	−0.42 (−0.72, −0.12)	0.006	28	−0.26 (−0.60, 0.08)	0.129	90	−0.35 (−0.53, −0.17)	<0.0001

Definition of abbreviations: BAMSE = Swedish Barn/Children, Allergy, Milieu, Stockholm, Epidemiological survey; CC16 = club cell secretory protein; CI = confidence interval; MAAS = UK Manchester Asthma and Allergy Study; n = number of participants; N = total number of observations; ref = reference group; TCRS = Tucson Children’s Respiratory Study.

Low lung function was defined using FEV₁/FVC percent predicted (see the Methods section of the online supplement). Results were derived from random coefficient models, adjusted for age and sex.