Alzheimer Disease
WHAT IS IT?
TREATMENTS
Alzheimer's is a progressive type of dementia that affects memory, thinking, and behavior serious enough to interfere with daily life.
Accounts for 60-70% of dementia cases among older adults.
Affects 5-10% of the population greater than 65 years of age and 40% age 85 years and older.
CAUSATIVE FACTORS
Brain proteins fail to function normally which form plaques and tangles leading to damaged neurons, and loss of connection and communication.
MOLECULAR AND GENETIC DETAILS
PATHOPHYSIOLOGIC ETIOLOGY
Formation of amyloid plaques and neurofibrillary tangles in the cortex and hippocampus which lead to progressive neuron loss
Plaques: Beta amyloid fragment clusters together forming amyloid plaques which disrupt cell-to-cell communication.
Tangles: Tau proteins form neurofibrillary tangles which disrupt the transport system.
COMMON FINDINGS
DIAGNOSTIC TESTS
RISK FACTORS
Age
E4 allele
Neurodegeneration and decreased cognition including loss of memory, facial recognition, language capability, recall, loss of judgement, and personality alterations.
Definitive diagnosis occurs postmortem with direct examination of the brain.
Diagnosis of exclusion
Down Syndrome
Sex
Mild cognitive impairment
Past head trauma
Lifestyle and heart health
Medications temporarily affect disease severity and progression
Two types of drugs to treat cognitive symptoms: Cholinesterase inhibitors and Memantine (Namenda)
Gene causing Alzheimer's is located on chromosome 21. This gene is present in 3 copies in trisomy 21, which leads to amyloid deposition and the occurance of Alzheimer Disease in individuals with down syndrome.
Individuals with one copy of e4 allele are 2-5x more likely to develop Alzheimers and those with two copies are 5-10x more likely to develop Alzheimers. Europeans and Japanese are at highest risk of having this allele.
Family history and genetics
Risk doubles with affected first degree relative
Autosomal dominant in 10% of cases
Genetically heterogenous disorder
Explained on attached sheet with pictures. (It is a little complicated to be explaining in concept map.)