Table 1.

Comparison of population characteristics of participants in the whole cohort with those with DNA methylation data in IOW cohort

Parameter	Total cohort n=1313	Participants with DNA-M data at age 18 n=370	p-value
	Median (5%, 95% value); n
Height
Boys	178 (167, 190); 483	177.3 (167, 187.3); 124	0.3
Girls	164 (154.5, 175); 511	165 (154, 176); 243	0.44
Weight
Boys	69 (55.6, 91.2); 468	70 (56, 97.2); 123	0.38
Girls	61.14 (48.5, 90.1); 502	61.45 (50.4, 89.1); 240	0.63
BMI
Boys	21.7 (18.1, 30.0); 465	21.85 (18.3, 29.1); 123	0.38
Girls	22.86 (18.2, 13.7); 499	22.88 (19.1, 32.9); 240	0.57
FVC
Boys	5.34 (4.21, 6.60); 395	5.34 (4.11, 6.70); 119	0.99
Girls	3.98 (3.1, 4.8); 443	4.05 (3.19, 5.02); 237	0.07
FEV1
Boys	4.55 (3.64, 5.63); 396	4.57 (3.59, 5.62); 119	0.59
Girls	3.48 (2.72,4.17); 443	3.54 (2.81, 4.26); 237	0.08
FEV1/FVC
Boys	0.87 (0.74, 0.98); 396	0.87 (0.77, 0.99); 119	0.6
Girls	0.88 (0.75, 0.98); 443	0.88 (0.75, 0.98); 237	0.66
FEF25-75%
Boys	4.97 (3.23, 6.84); 396	5.12 (3.42, 6.94); 119	0.42
Girls	4.00 (2.5, 5.4); 443	4.05 (2.55, 5.42); 237	0.33
ENO
Boys	19.0 (7, 108); 387	18.00 (7, 78); 113	0.27
Girls	14.0 (5, 64); 435	13.00 (6, 64); 234	0.26
Serum leptin (ng/ml)
Boys	1.22 (0.40, 13.11); 288	1.2 (0.40, 16.04); 120	0.99
Girls	13.11 (2.4, 54.57); 265	13.11 (2.76, 54.57); 239	0.7
Maternal asthma during pregnancy			0.41
Yes	137 (10.51)	44 (12.02)
No	1167 (89.49)	322 (87.98)
Paternal asthma			0.23
Yes	128 (9.88)	43 (11.88)
No	1168 (90.12)	319 (88.12)
Atopy Status
Boys	194 (47.7)	50 (40.6)	0.17
Girls	159 (35.65)	76 (31.4)	0.26
Maternal smoking status			0.23
Yes	305 (23.34)	75 (20.83)
No	1002 (76.66)	293 (79.62)
Current smoking status			0.29
Yes	368 (28.79)	95 (25.96)
No	910 (71.21)	271 (74.04)
Sex			<0.0001
Male	653 (49.73)	125 (33.78)
Female	660 (50.3)	245 (66.22)