TABLE 5.

THE ASSOCIATION BETWEEN INCREASING LEVELS OF DNA METHYLATION ACROSS ARG2 LOCI AND PERCENT CHANGE IN FRACTIONAL CONCENTRATION OF NITRIC OXIDE

	Combined* (n = 876)		Children with Asthma† (n = 120)		Children with No Asthma† (n = 756)
No. of Methylated ARG2 Loci	% Difference	95% Confidence Interval	% Difference	95% Confidence Interval	% Difference	95% Confidence Interval	Pint*
0–1	Reference		Reference		Reference		0.03
2	−12.3	(−22.6 to −0.6)	−20.1	(−45.3 to 16.7)	−9.7	(−20.6 to 2.8)
3	−12.5	(−22.5 to −1.3)	−42.3	(−60.3 to −16.3)	−6.6	(−17.5 to 5.7)
Trend	−5.6	(−10.9 to 0.1)	−24.6	(−37.5 to −9.5)	−2.3	(−8 to 3.7)	0.007

^*P value testing the interaction between ARG2 number of methylated loci and asthma status in model adjusted for age, sex, race, plate, town, month of DNA collection, asthma medicine used, education, and asthma.

^†Analyses are adjusted for age, sex, race, plate, town, month of DNA collection, asthma medicine used, and education.