Table 7.

Estimated AD-associated neuronal loss in 51-to 59-y-old DS subjects (loss per day and per million neurons/day)

Structures/ subdivisions	Number of neurons in 43- to 49-y-old DS subjects, N = 4, Mean and (SD)	Number of neurons in 51-to 59-yr-old DS subjects, N = 17, Mean and (SD)	Neurons lost. difference between 43- to 49 and 51- to 59-y-old DS subjects	Number of neurons in DS reference group 26-to 41-y-old (100%)	Neurons lost (%) in 51–59-y-old DS subjects reference group, 26-to 41-y-old	P <	Number of neurons lost/day	Number of neurons lost/ million/day
Entorhinal c.all layers	10,470,333 (1,003,992)	5,702,533 (2,101,830)	4,767,800	9,779,100	48.8	0.002***	1520.8	145.3
Entorhinal c. islands	609,481 (68,719)	192,314 (84,474)	417,167	600,288	69.5	0.001***	133.1	218.3
CA1	5,271,466 (699,001)	2,986,260 (1,727,048)	2,285,206	7,584,266	30.1	0.05*	728.9	138.3
CA2	1,363,407 (350,731)	919,574 (287,449)	443,833	1,375,511	32.3	0.04*	141.6	103.8
CA3	969,837 (225,781)	655,428 (255,405)	314,409	1,062,288	29.6	ns	100.3	103.4
CA4	950,304 (255,206)	658,923 (467,298)	291,381	1,105,866	26.3	ns	92.9	97.8
Subiculum	2,575,933 (293,733)	1,760,757 (562,251)	815,176	3,049,650	26.7	0.03*	260.0	100.9
Amygdala	7,150,380 (940,312)	5,203,993 (1,311,409)	1,946,387	6,978,730	27.9	0.02*	620.9	86.8
Thalamus	13,488,304 (1,821,914)	12,891,781 (2,374,425)	596,524	14,774,176	4.0	ns	190.3	14.1
Substantia nigra	396,519 (76,289)	309,905 (65,494)	86,614	550,053	15.7	0.05*	27.6	69.7
MBC	994,389 (104,089)	783,233 (205,770)	211,156	981,577	21.5	ns	67.4	67.7
Caudate n	29,151,928 (7,214,428)	27,913,089 (10,600,000)	1,238,840	41,434,112	3.0	ns	395.2	13.6
Purkinje cells	10,569,930 (720,445)	11,715,680 (2,207,151)	0	14,247,128
Dentate n	463,150 (138,022)	520,173 (96,537)	0	510,829
			Total loss: 13,414,493 neurons		Mean loss: 28.0%		Mean loss: 356.6/d Total loss: 4,278.9/d	Mean loss: 96.6/ million/d

Loss calculated using the 8.6-year (3,135-day) difference in mean age between the groups as the denominator. *p < 0.05; **p < 0.01; ***p < 0.001