Table 5.

Unadjusted and adjusted geometric mean blood aluminum concentrations by ASD status (ASD and TD control) based on General Linear Models (GLM) that includes interaction between GSTP1 genotypes and ASD case status (ASD and TD control) (106 matched pairs).

Models	(Column A) Group Compared	Referent Group	GSTP1 Genotypes	Unadjusted Interactive Model (μg/L) **			Adjusted Interactive Model (μg/L) c
				Geometric Mean Al of Children with Group Compared in Column A *	Geometric Mean Al of Children with Referent Group *	p d	Geometric Mean Al of Children with Group Compared in Column A *	Geometric Mean Al of Children with Referent Group *	p d
Full a	ASD Case	TD Control	Ile/Ile	22.81	27.57	0.43	21.71	24.19	0.66
	ASD Case	TD Control	Ile/Val	22.54	26.02	0.38	23.16	23.39	0.96
	ASD Case	TD Control	Val/Val	25.56	14.00	0.03	24.39	14.60	0.07
Recessive b	ASD Case	TD Control	Val/Val	25.62	14.01	0.03	24.38	14.57	0.07
	ASD Case	TD Control	Ile/Ile or Ile/Val	22.62	26.50	0.18	22.62	23.75	0.73

* Mean AL indicates the geometric mean = Exp. [Mean (ln AL)]; ** In the univariable GLMs, the independent variables include pairs, ASD status, GSTP1, and GSTP1 interaction with ASD; ^a GSTP1 in the full model has three categories (Ile/Ile, Ile/Val, and Val/Val); ^b GSTP1 (REC) = GSTP1 in the recessive model has two categories (Val/Val, Ile/Ile or Ile/Val); ^c In multivariable GLMs in addition to the variables in the univariable model we adjusted for parental education levels, consumption of root vegetables (yam, sweet potato, or dasheen), avocado, and tuna (canned fish); ^d p-values are for the comparison of mean blood aluminum concentrations of children with the ASD case status in “Column A” compared to those with the TD control status in “referent group”, stratified by GSTP1 genotypes , based on CONTRAST option in the SAS program for GLMs as described in the Methods Section.