Table 6.

Estimated AD-associated neuronal loss in 43–49-yr-old DS subjects (loss per day and per million neurons/day)

Structures/ subdivisions	Number of neurons in 26- to 41-y-old DS subjects N = 4, Mean and (SD)	Number of neurons in 43- to 49-y-old DS subjects N = 4, Mean and (SD)	Neurons lost (vs. 26-to 41-y- old DS subjects)	Neurons lost (%)	P <	Number of neurons lost/day	Number of neurons lost/million/day
Entorhinal cortex—all layers	9,779,100 (255,051)	10,470,333 (1,003,992)	0.0	0.0		0
Entorhinal cortex—islands	600,288 (100,952)	609,481 (68,719)	0.0	0.0		0
CA1	7,584,266 (1,745,386)	5,271,466 (699,001)	2,312,800	30.5	ns	487.4	64.3
CA2	1,375,511 (435,724)	1,363,407 (350,731)	12,104	0.9	ns	2.6	1.9
CA3	1,062,288 (467,225)	969,837 (225,781)	92,451	8.7	ns	19.5	18.3
CA4	1,105,866 (159,035)	950,304 (255,206)	155,562	14.0	ns	32.8	29.6
Subiculum	3,049,650 (492,839)	2,575,933 (293,733)	473,717	15.5	ns	99.8	32.7
Amygdala	6,978,730 (724,797)	7,150,380 (940,312)	0.0	0.0		0	0
Thalamus	14,774,176 (837,618)	13,488,304 (1,821,914)	1,285,871	8.7	ns	271.0	18.3
Substantia nigra	550,053 (107,611)	396,519 (76,289)	135,534	27.9	ns	32.4	58.8
MBC	981,577 (124,910)	994,389 (104,089)	0.0	0.0		0	0
Caudate nucleus	41,434,112 (4,788,237)	29,151,928 (7,214,428)	12,282,183	29.6	0.03*	2,588.4	62.5
Purkinje cells	14,247,128 (2,946,322)	10,569,930 (720,445)	3,677,198	25.8	ns	775.0	54.4
Dentate n	510,829 (26,959)	463,150 (138,022)	47,679	9.3	ns	10.0	19.7
			Total loss: 20,475,099 neurons	Mean loss: 11.9%		Mean loss 308.4/d Total loss 4,318.9/d	Mean loss 25.7/million/day

Losses per day and per million neurons per day were calculated using the 13-year (4,745-day) difference in mean age between the groups as the dominator

^*p < .05