<unk>  is the most common cause of dementia among older people. Dementia is a loss of thinking, remembering, and reasoning skills that interferes with a person's daily life and activities. Other causes of dementia include blood vessel<unk>  in the brain (called vascular dementia), Parkinson's<unk> , frontotemporal dementia, and Lewy body dementia. The first case of<unk>  was described by a German psychiatrist named Alöis<unk>  in the year 1901. For many decades after<unk> 's original description, there was little progress in defining the pathogenesis of<unk>  occurred. In the mid 1970's, it was found that the levels of acetylcholine decrease in brains of individuals undergoing neurodegeneration due to<unk> . In early 1980's major<unk> vances in biochemistry and molecular genetics allowed the use of compositional analyses and immunocytochemistry to explain the structure of tangles and plaques found in the brains of<unk>  patients. The term<unk>  was subsequently formally<unk> opted in medical nomenclature to describe individuals of all ages with a characteristic common symptom pattern,<unk>  course, and neuropathology.<unk>  may be classified according to severity into mild, moderate and severe dementia. It may also be classified based on age of onset into early onset and late onset<unk> . Another method of classification of<unk>  is based on the course of<unk>  into pre-dementia, early dementia, moderate dementia and<unk> vanced dementia.<unk><unk>  <unk> , is a progressive neurodegenerative disorder. The dysfunction of amyloid precursor protien (APP) metabolism and the resulting build up of of Aβ peptides and their aggregation in the form of senile plaques in the brain parenchyma of individuals have been considered pivotal for neurodegeneration in the<unk> . Cognitive impairment in patients with<unk>  is closely associated with synaptic loss in the neocortex and limbic system. The microscopic histopathological features of<unk>  consist of neurofibrillary tangles, senile plaques, neuronal loss, and with or without cerebral amyloid angiopathy.<unk>  may be caused by trisomy of chromosome 21, familial inheritance of mutations in either presenilin 1 gene, presenilin 2 gene or APOE4 gene. Presenilin mutations are associated with early onset<unk> , whereas APOE mutations are associated with late onset<unk> . Environmental factors, such as aging, low level of education and head trauma may also contribute to the development of<unk> . An estimated 5.5 million Americans of all ages have<unk> . An estimated 10,000 per 100,000 individuals aged greater than 65 years have been known to be living with<unk>  in the United States. The diagnosis of<unk>  <unk>  is made on the basis of clinical criteria described by either the National Institute on Aging and the<unk> 's Association (NIA-AA) or DSM-V (Diagnostic and Statistical Manual of Mental Disorders, fifth edition). Histopathologic examination for diagnosis of<unk>  is rarely done. Elderly patients presenting with progressive decline in memory and other cognitive impairments such as aphasia, agnosia or apraxia should be suspected for<unk> . In these patients, mental status examination (MSE) and neuropsychological testing should be performed to further evaluate the status of cognitive abilities. Diagnostic tools for the examination of the patient include mini- mental status examination (MMSE), Montreal Cognitive Assesment (MOCA) and instruments of activities of dailing living (IADL).  Characteristic findings on MRI suggestive of<unk>  include reduced hippocampal volume and medial temporal lobe atrophy. There is no known cure for<unk>  <unk> . Available treatments offer relatively small symptomatic benefit but remain palliative in nature. Current treatments can be divided into pharmacological, psychosocial, and caregiving. Acetylcholine esterase inhibitors increase the amount of acetylcholine in the brain and are a major part of pharmacotherapy for<unk> . Major drugs include, donepezil, rivastigmine and galantamine, these drugs help with the cognitive symptoms of the<unk> . Associated psychosis and depression may be managed with antipsychotics and selective serotonin reuptake inhibitors (SSRIs). Caregiving plays a pivotal role in the management of patients suffering from<unk> .
Alzheimer's disease
Multi-infarct dementia
Dementia with Lewy bodies
Parkinson's disease
Pick's disease
Semantic dementia
Creutzfeldt-Jakob disease
Dementia