Table 2. Estimated Linear Associations Between Stress and Environmental Factors From Single-Exposure Models.

Environmental factor	Environmental factor IQR	Effect estimate (95% CI)a	P value
Exposure to secondhand smoke	NA	1.23 (0.84-1.62)	<.001
ALAN, VIIRS, nW/cm2/srb	2.44 (12.2 to 35.2)	0.23 (0.02 to 0.45)	.03
ALAN, world atlas, mcd/m2	2.44 (2.53 to 4.98)	0.44 (0.03 to 0.84)	.04
EVI	0.06 (0.17 to 0.23)	−0.29 (−0.47 to −0.10)	.003
NDVI	0.11 (0.27 to 0.38)	−0.28 (−0.50 to −0.07)	.008
NRP, ppbc
Total	13.2 (7.49 to 20.73)	0.17 (0.05 to 0.28)	.005
Freeway	11.1 (4.39 to 15.52)	0.14 (0.04 to 0.24)	.005
Nonfreeway	3.34 (2.05 to 5.39)	0.05 (−0.15 to 0.25)	.10
Noise, dB	10.2 (67.38 to 77.61)	0.10 (−0.06 to 0.26)	.63

Abbreviations: ALAN, artificial light at night; EVI, enhanced vegetation index; IQR, interquartile range; mcd/m², millicandela per meter squared; NA, not applicable; NDVI, normalized difference vegetation index; NRP, near-roadway pollution; nW/m² per centimeter, nanowatts per meter squared; ppb, parts per billion; VIIRS, Visible Infrared Imaging Radiometer Suite.

^aAll models adjusted for height, body mass index, race, ethnicity, community, and effect estimates of continuous variables are scaled by their IQR.

^bArtificial light at night from the Visible Infrared Imaging Radiometer Suite in nanowatts per centimeter squared per steradian.

^cNitrogen oxides.