What causes alzhemeir
Alzheimer's disease (AD), also known simply as Alzheimer's, is a neurodegenerative disease characterized by progressive cognitive deterioration together with declining activities of daily living and neuropsychiatric symptoms or behavioral changes. It is the most common type of dementia.
The most striking early symptom is loss of short-term memory (amnesia), which usually manifests as minor forgetfulness that becomes steadily more pronounced with illness progression, with relative preservation of older memories. As the disorder progresses, cognitive (intellectual) impairment extends to the domains of language (aphasia), skilled movements (apraxia), recognition (agnosia), and those functions (such as decision-making and planning) closely related to the frontal and temporal lobes of the brain as they become disconnected from the limbic system, reflecting extension of the underlying pathological process. This pathological process consists principally of neuronal loss or atrophy, principally in the temporoparietal cortex, but also in the frontal cortex, together with an inflammatory response to the deposition of amyloid plaques and neurofibrillary tangles.
The ultimate cause of the disease is unknown. Genetic factors are known to be important, and dominant mutations in three different genes have been identified that account for a much smaller number of cases of familial, early-onset AD. For the more common form of late onset AD (LOAD), ApoE is the only repeatibly confirmed susceptibility genes for AD. In 2007, evidence suggested a possible association between SORL1 alleles and AD.[1]
flu shots and other vaccines
Alzheimer's disease is a complex disease and there are a number of explanations about what causes Alzheimer's. Alzheimer鈥檚 disease begins to damage the brain years before symptoms appear. Why pathological changes occur in the brain leading to such profound damage is an area of scientific investigation that is making considerable progress. Most scientists believe that Alzheimer's disease begins with the buildup of beta amyloid protein in the brain. There are a number of theories about why this should happen. Genetic risk factors as a cause of Alzheimer's disease is also an area of intense investigation.