Public health genetics of Alzheimer's disease: From the identification of genetic risk factors to the public policies surrounding long-term care insurance

Alzheimer's disease (AD) is the most common form of dementia in individuals older than sixty-five and presents a substantial public health problem. Pathologically, AD is characterized by the presence of neurofibrillary tangles (NFTs) and amyloid beta (Abeta) plaques. The ultimate cause of AD is the loss of neurons and the synaptic connections between them and it has been proposed that the innate immune response to the deposition of Abeta plaques and NFTs might exacerbate neuronal degeneration and play an important role in the risk or progression of AD. The case-control genetic association study presented in Chapter II determined that an association exists between TNFalpha promoter region polymorphisms and risk of AD in the population studied. However, Chapter III analyses suggested that genetic variation in IL10 or TNFalpha is not associated with rate of cognitive decline among the AD cases or severity of neuropathological outcomes including gross brain atrophy and degree of neurofibrillary tangle and neuritic plaque pathology.; The identification of AD susceptibility genes may ultimately lead to the development of a genetic test to predict risk of AD. However, there are many concerns regarding the use of predictive genetic tests. Chapter IV provided a framework to determine whether genetic information resulting from predictive genetic tests will affect an individual's access to long-term care insurance, which is one method of covering the tremendous costs of long-term nursing home or hospice care for individuals suffering from Alzheimer's disease.