Table 2.

Associations between total brain gray-matter and white-matter volumes (mm³) and air pollution: unstandardized coefficients and 95% confidence intervals from linear regression.

	Gray Matter		White Matter
	b	95%CI	b	95%CI
PM2.5
Unadjusted	838 *	151, 1524	243	−340, 826
Adjusted	−659 *	−1179, −140	−579 *	−1144, −14
PM2.5 to 10
Unadjusted	−549	−1334, 237	410	−257, 1077
Adjusted	−633 *	−1218, −47	142	−495, 779
PM10
Unadjusted	−307	−682, 68	189	−129, 508
Adjusted	−528 ***	−809, −248	−22	−328, 283
Nitrogen Dioxide
Unadjusted	195 ***	94, 296	83	−3, 169
Adjusted	−103 **	−180, −26	−72	−155, 12
Nitrogen Oxides
Unadjusted	88 ***	39, 138	39	−3, 81
Adjusted	−42 *	−79, −4	−26	−67, 15

Note: adjusted models include age, sex, race, education, income, overall health, BMI, smoking status and frequency of drinking alcohol. N = 18,292. Source: UK Biobank. * p < 0.05, ** p < 0.01, *** p < 0.001.