背景:我们估计了血浆淀粉样肽水平(Aβ1-42和Aβ1-40)作为阿尔茨海默病(AD)的诊断生物标志物,并评估了其与临床严重程度和18F-氟脱氧葡萄糖正电子发射断层扫描(18F-FDGPET)Z评分的关系。
方法:采用病例对照研究。诊断和统计手册-IV,Dubois,采用NIA-AA标准诊断AD。估计不同脑区的血浆Aβ1-42和Aβ1-40浓度和18F-FDGPETZ评分。
结果:纳入47名认知障碍患者(AD=29,轻度认知障碍=18)和33名年龄匹配的对照组。与对照组相比,AD组的血浆Aβ1-42水平显着升高(P=0.046),截止值>5.7ng/mL的特异性为96.9%,灵敏度为27.6%,阳性预测值88.9%,鉴别AD患者与对照组的阴性预测值为60.4%。双侧顶叶Aβ1-40/Aβ1-42比值与18F-FDGPETZ评分显著相关,temporal,额叶联合区,和后扣带回区域。
结论:作为AD的诊断生物标志物,在印度人群中,血浆Aβ1-42水平显示出良好的特异性,但敏感性较低。
BACKGROUND: We estimated plasma amyloid-peptides levels (Aβ1-42 and Aβ1-40) as diagnostic biomarker of Alzheimer\'s disease (AD) and evaluated its association with clinical severity and 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) Z score of the different brain regions in the Indian population.
METHODS: A
case-control study was conducted. Diagnostic and statistical manual-IV, Dubois, and NIA-AA criteria were used for the diagnosis of AD. The plasma Aβ1-42 and Aβ1-40 concentration and 18F-FDG PET Z score were estimated for different brain regions.
RESULTS: Forty-seven cognitive impairment patients (AD = 29, mild cognitive impairment = 18) and 33 age-matched controls were enrolled. Plasma Aβ1-42 level was significantly higher in the AD group compared to controls (P = 0.046) and a cut-off >5.7 ng/mL has a specificity of 96.9%, sensitivity of 27.6%, positive predictive value 88.9%, and negative predictive value 60.4% for differentiating AD patients from controls. Significant correlation was seen between Aβ1-40/Aβ1-42 ratio and 18F-FDG PET Z score in the bilateral-parietal, temporal, frontal-association area, and posterior-cingulate areas.
CONCLUSIONS: As a diagnostic biomarker of AD, plasma Aβ1-42 level showed good specificity but low sensitivity in the Indian population.