RESUMO
Objective To test amyloid beta protein(Aβ)40 and Aβ42 levels in CSF and apolipoprotein E (ApoE) genotype in patients with Alzheimer's disease(AD) and study whether or not the Aβ is related to the severity of dementia and the genotypes of ApoE.Methods 48 AD patients including 27 cases of mild type and 21 cases of serious type and 35 normal controls were selected.Aβ40 and Aβ42 in CSF and ApoE genotype were analyzed.Results Aβ40 levels were ( 12.3 ±4.6) μg/L,( 11.7 ±4.1 ) μg/L,( 12.6 ±4.9) μg/L and ( 11.0 ±3.7) μg/L(t = 1.377,0.705 and 1.385 ,all the p values were greater than 0.05) and Aβ42 levels were ( 105.3 ±25.4) ng/L,(110.7 ±21.7) ng/L,(96.9 ±23.9) ng/L and (123.5 ±29.6) ng/L(t=3.006,2.832,and 3.488,all the p values less than 0.01 ),in AD group,mild AD group,moderate to serious AD group and normal controls,respectively.Aβ40 levels were (11.9 ± 5.2) μg/L vs.(10.5 ± 3.8) μg/L in AD and controls with ApoEε4(t=0.696,P＞0.05) and (12.6 ±4.5) μg/L vs.(11.4 ±3.4) μg/L without ApoEε4(t = 1.008,P＞0.05).Aβ42 levels were (99.7 ± 23.8) ng/L vs.( 129.6 ± 31.0) ng/L in AD and controls with ApoEε4( t =1.632,P ＞ 0.05 ) and ( 110.4 ± 28.4) ng/L vs.( 129.6 ± 31.0) ng/L in those without ApoEε4 ( t = 2.110,P ＜0.05 ).Conclusions The CSF level of Aβ is abnormal in AD,and it is related to the severity of the disease and the ApoE genotypes.