TABLE 5:

Least-squares means of brain volumes as a function of genotype in 70 patients with hemoglobin SS, 20 control subjects with hemoglobin AS, and 23 control subjects with hemoglobin AA

Volume and Genotype	5.0 Years Old	9.5 Years Old	11.5 Years Old
Total brain	Means ± SE
AA	98.79 ± 2.50	97.51 ± 1.57	96.95 ± 1.66
AS	97.37 ± 3.28	97.12 ± 1.70	97.01 ± 1.87
SS	92.18 ± 1.34	94.59 ± 0.89	95.66 ± 1.00
	P Value
AA vs SS	0.0217	NS	NS
AS vs SS	NS	NS	NS
AA vs AS	NS	NS	NS
White matter	Means ± SE
AA	25.61 ± 1.47	26.53 ± 0.92	26.94 ± 0.98
AS	27.90 ± 1.93	28.48 ± 0.99	28.73 ± 1.10
SS	25.00 ± 0.79	26.96 ± 0.53	27.83 ± 0.59
	P Value
AA vs SS	NS	NS	NS
AS vs SS	NS	NS	NS
AA vs AS	NS	NS	NS
Gray matter	Means ± SE
AA	68.95 ± 1.95	65.55 ± 1.19	64.03 ± 1.26
AS	65.52 ± 2.49	62.95 ± 1.29	61.82 ± 1.40
SS	60.70 ± 1.02	61.17 ± 0.68	61.37 ± 0.77
	P Value
AA vs SS	0.0002	0.0018	NS
AS vs SS	NS	NS	NS
AA vs AS	NS	NS	NS
Central gray matter	Means ± SE
AA	11.99 ± 0.49	11.37 ± 0.31	11.09 ± 0.32
AS	11.94 ± 0.64	11.41 ± 0.33	11.17 ± 0.37
SS	10.48 ± 0.26	10.61 ± 0.18	10.66 ± 0.20
	P Value
AA vs SS	0.0078	0.0340	NS
AS vs SS	0.0374	0.0343	NS
AA vs AS	NS	NS	NS
Cortical gray matter	Means ± SE
AA	56.96 ± 1.45	54.18 ± 0.91	52.94 ± 0.96
AS	53.80 ± 1.90	51.40 ± 0.98	50.33 ± 1.08
SS	51.07 ± 0.78	50.86 ± 0.52	50.77 ± 0.58
	P Value
AA vs SS	0.0005	0.0019	NS
AS vs SS	NS	NS	NS
AA vs AS	NS	0.0397	NS
CSF	Means ± SE
AA	4.22 ± 0.77	5.44 ± 0.48	5.98 ± 0.51
AS	3.95 ± 1.00	5.70 ± 0.52	6.47 ± 0.58
SS	6.48 ± 0.41	6.46 ± 0.28	6.45 ± 0.31
	P Value
AA vs SS	0.0111	NS	NS
AS vs SS	0.0221	NS	NS
AA vs AS	NS	NS	NS

Note.—NS indicates not significant; SE, standard error.