ADNI（Alzheimer`s disease neuroimaging initiative）介紹

第一部分：

ADNI數據庫則是一個龐大的公開數據集，收集了最終被診斷出患有阿爾茨海默症、輕度認知障礙或沒有任何障礙的患者的PET掃描數據。

 

以上內容來自：https://xw.qq.com/partner/hwbrowser/20190108A0PR3B/20190108A0PR3B00?ADTAG=hwb&pgv_ref=hwb&appid=hwbrowser&ctype=news

 

第二部分：

http://adni.loni.usc.edu

阿爾茨海默病神經影像學倡議（ADNI）是一項縱向多中心研究，旨在開發臨牀、影像、遺傳和生化生物標記物，用於早期檢測和跟蹤阿爾茨海默病（AD）。

目標：1. AD的早診，在pre-dementia以前的診斷，發現可用於跟蹤疾病進展的marker；

　　    2. 在AD的早期，運用新的治療方法來干預、診斷和治療AD；

　　    3. 數據共享

 

ADNI已經報道了下面的這些發現：

1. 在病人還未出現記憶喪失標誌前，AD的病理已經出現了，而且這些人（認知正常）有輕微的腦萎縮；

2. AD病人有一些典型特徵：澱粉樣蛋白沉積、葡萄糖代謝降低、大腦的結構變化；

3. 認知降低與tau的沉積更相關，相比Aβ；

4.大腦鏈接體逐漸破壞是AD的特徵。隨着疾病進展，大腦重要區域的鏈接愈來愈少；

5.除了APOE4，許多基因致使了AD。從目前發現的20個基因中，ADNI的數據發現/確認了其中的10個基因；

6.腦血管的疾病可以加速AD的進展；

7.認知正常和輕度認知損傷羣體在病理上存在異質性。一些人沒有發病，一些人很快出現了AD症狀，一些人出現了癡呆而不是AD。

 

Biomarker是生物狀態的一種標記。ADNI用多種marker來預測AD的發病。

　　1.檢測腦脊液的Aβ或者經過 amyloid PET imaging；

　　2.檢測腦脊液中的tau蛋白或着用FDG-PET測量的突觸功能障礙，來檢測神經退行性病變；

　　3.用核磁掃描檢測腦萎縮，一般是medial temporal lobe內側顳葉區域；

　　4.經過認知測試來檢測記憶丟失；

　　5.經過認知測試評估認知降低的臨牀指標。

　前3種在癡呆以前就能夠檢測到；後2種是經典的癡呆診斷標準。

 

1. b-amyloid (A?) measured in cerebrospinal fluid or by amyloid PET imaging
2. Neurodegeneration indicated by tau protein measured in cerebrospinal fluid, or by synaptic dysfunction, measured by FDG-PET
3. Brain atrophy, mostly in the medial temporal lobe, measured by structural MRI
4. Memory loss, measured by cognitive tests
5. Clinical function, indicated by general cognitive decline measured by cognitive tests.

Changes 1-3 are indicated by biomarkers that can be observed prior to a dementia diagnosis, while changes 4-5 are the classic indicators of dementia diagnosis.

 

The Alzheimer’s Disease Neuroimaging Initiative (ADNI) is a longitudinal multicenter study designed to develop clinical, imaging, genetic, and biochemical biomarkers for the early detection and tracking of Alzheimer’s disease (AD). Since its launch more than a decade ago, the landmark public-private partnership has made major contributions to AD research, enabling the sharing of data between researchers around the world.

Three overarching goals of the ADNI study are:

1. To detect AD at the earliest possible stage (pre-dementia) and identify ways to track the disease’s progression with biomarkers.
2. To support advances in AD intervention, prevention, and treatment through the application of new diagnostic methods at the earliest possible stages (when intervention may be most effective).
3. To continually administer ADNI’s innovative data-access policy, which provides all data without embargo to all scientists in the world.

Studies using ADNI cross-sectional and longitudinal data from multiple modalities have reported that:

• AD pathology is already present in people with no outward sign of memory loss and these cognitively normal people may already have subtle brain atrophy
• There are typical patterns of amyloid deposition, declines in glucose metabolism, and structural brain changes that occur in AD
• Cognitive decline is more closely linked to tau then Aß deposition
• AD is characterized by the progressive disruption of the brain connectome. As the disease progresses, there are fewer connections between essential brain regions.
• Many genes in addition to APOE4 underlie AD. ADNI data has helped to identify or confirm 10 of the approximately 20 genes currently identified
• Cerebrovascular disease can accelerate disease progression in AD
• Both the cognitively normal and MCI groups are pathologically heterogeneous. Some people show no signs of AD, some show signs of progressing to AD quickly, and others show signs of progressing to dementias other than AD