Table 3.

Association of 28-day average levels of PM_2.5 and PM components with renal health outcomes in the NAS.

Renal health outcome	Air pollutant	Method 1^a		Method 2^b
Renal health outcome	Air pollutant	Estimates per IQR change (SE)	p-value	Estimates per IQR change (SE)	p-value
SUA (mg/dL)	PM_2.5	0.067 (0.044)	0.13	0.214 (0.069)	0.0020*
	Na	−0.182 (0.059)	0.0021*	−0.040 (0.074)	0.59
	Al	−0.048 (0.038)	0.22	−0.564 (0.143)	<0.0001*
	Si	0.010 (0.031)	0.76	0.527 (0.118)	<0.0001*
	Ca	−0.032 (0.040)	0.42	−0.160 (0.068)	0.018*
	V	0.130 (0.063)	0.04*	0.244 (0.074)	0.0009*
	Fe	−0.009 (0.045)	0.85	−0.075 (0.069)	0.28
	Cu	−0.012 (0.038)	0.74	0.048 (0.041)	0.25
BUN (mg/dL)	PM_2.5	0.011 (0.199)	0.96	−0.239 (0.251)	0.34
	V	0.393 (0.280)	0.16	0.403 (0.291)	0.17
	Zn	0.080 (0.193)	0.68	0.003 (0.201)	0.99
eGFR (mL/min/1.73 m²)	S	−2.581 (0.979)	0.0085*	−1.281 (0.598)	0.032*
eGFR (mL/min/1.73 m²)	Pb	−1.384 (0.542)	0.011*	−1.008 (0.453)	0.049*
		OR per IQR change (95% CI)	p-value	OR per IQR change (95% CI)	p-value
Odds of CKD	BC	1.10 (0.89 – 1.37)	0.36	0.82 (0.62 – 1.08)	0.15
Odds of CKD	S	1.45 (1.06 – 1.99)	0.020*	1.39 (1.14 – 1.68)	0.0008*

^a:

Method 1: Mixed-effect linear / logistic models for PM_2.5 or single PM components adjusting for age, body mass index, smoking status, alcohol consumption, systolic blood pressure, diastolic blood pressure, hypertension, stroke, coronary heart disease, diabetes, season, and corresponding temperature and humidity. Corresponding PM_2.5 levels were additionally added in models for PM components (two-pollutant model).

^b:

Method 2: Mixed-effect linear / logistic models for predictable air pollutants selected by BKMR. Models included all selected air pollutants simultaneously and covariates used for Method 1.

PM, particulate matter; NAS, Normative Aging Study; IQR, interquartile range; SE, standard error; SUA, serum uric acid; BUN, blood urea nitrogen; eGFR, estimated glomerular filtration rate; CKD, chronic kidney disease; OR, odds ratio; CI, confidence interval