The effect of high polycyclic aromatic hydrocarbon exposure on biological aging indicators

Table 4 SEM results of mediation analysis for mtDNAcn

	Endogenous variables	Exogenous variables	Beta Coef.	95%CI		p-value
	Endogenous variables	Exogenous variables	Beta Coef.	Lower	Upper	p-value
Structural Equations	mtDNAcn	Occup_PAHs	-0.0005	-0.0022	0.0013	0.598
		Environ_PAHs	-1.4688	-9.4714	6.5340	0.719
		nDNA_changes	0.0690	0.0483	0.0896	0.000
		Chronic diseases	0.0338	-0.0293	0.0969	0.294
	nDNA_changes	Occup_PAHs	0.0214	0.0054	0.0373	0.009
	nDNA_changes	Environ_ PAHs	7.1108	6.0885	8.1331	0.000
Measurement	Diet ← Environ_ PAHs		1	(constrained)
	Indoor ← Environ_ PAHs		4.4960	-2.2258	1.1217	0.190
	Outdoor ← Environ_ PAHs		5.6125	-29.545	40.771	0.754
	MN← nDNA_changes		1	(constrained)
	Anti-BPDE-DNA adducts ← nDNA_changes		1.8001	1.6520	1.9483	0.000
	LINE-1 (%mC) ← nDNA_changes		1.3820	1.1354	1.6285	0.000
	p53 (%mC) ← nDNA_changes		-2.4248	-3.0079	-1.8417	0.000
	Alu (%mC) ← nDNA_changes		0.2372	0.2365	0.2379	0.000
	HICI (%mC) ← nDNA_changes		-0.8902	-1.1999	-0.5805	0.000
	IL-6 (%mC) ← nDNA_changes		1.7827	0.2553	3.3102	0.022
	p16 (%mC) ← nDNA_changes		-0.0409	-0.0557	-0.0261	0.000
	GSTM1 ← nDNA_changes		0.0241	-0.0122	0.0606	0.193
Covariances	cov(Occup_PAHs, Environ_PAHs)		0.2981	-115.55	1.7517	0.688
Covariances	cov(Chron_d,Environ_ PAHs)		-0.0096	-0.0329	0.0137	0.420

Three groups of SEM results (structural equations, measurement and covariances) for the mediation analysis; standardized beta coefficients (with “minus” sign indicating inverse relationship) with lower and upper limit of 95% confidence intervals (95%CI) and p-values. Standard Error adjusted for 2 clusters (coke-oven workers and controls). SEM’s goodness-of-fit statistics at bottom of table. Number of observations = 87
Abbreviations: mtDNAcn Mitochondrial DNA copy number, nDNA_changes Latent variable estimated by SEM (overall change of DNA) based on MN, Anti-BPDE-DNA adducts, LINE-1, p53, Alu, HICI, IL-6, p16, GSTM1, MN Micronuclei, PAHs Exposure to Polycyclic aromatic hydrocarbons, Environ_PAHs Latent variable estimated by SEM (environmental exposure to PAHs), Occup_PAHs (years of work in the cokery) × (1-pyrenol in μmoles/mol creatinine)
Goodness of fit statistics: Standardized root mean squared residual (SRMR) = 0.092; Coefficient of determination (CD) = 0.914; Stability index = 0 (SEM satisfies stability condition)

ISSN: 1476-069X