- Significant loss of intellectual abilities such as memory capacity, severe enough to interfere with social or occupational functioning. Criteria for the diagnosis of dementia include impairment of attention, orientation, memory, judgment, language, motor and spatial skills, and function. By definition, dementia is not due to major depression or schizophrenia. Dementia is reported in as many as 1% of adults 60 years of age. It has been estimated that the frequency of dementia doubles every five years after 60 years of age. Alzheimer's disease is the most common cause of dementia. There are many other causes of dementia, including (in alphabetical order): AIDS (due to HIV infection), alcoholism (the dementia is due to thiamine deficiency), brain injury, brain tumors, Creutzfeldt-Jakob disease, dementia with Lewy bodies (tiny round structures made of proteins that develop within nerve cells in the brain), drug toxicity, encephalitis, meningitis, Pick disease (a slowly progressive deterioration of social skills and changes in personality leading to impairment of intellect, memory, and language), syphilis, thyroid disease (hypothyroidism) and vascular dementia (damage to the blood vessels leading to the brain).
* * *The loss, usually progressive, of cognitive and intellectual functions, without impairment of perception or consciousness; caused by a variety of disorders including severe infections and toxins, but most commonly associated with structural brain disease. Characterized by disorientation, impaired memory, judgment, and intellect, and a shallow labile affect. SYN: amentia (2). [L. fr. de- priv. + mens, mind]- catatonic d. d. with catatonic symptoms.- epileptic d. d. occurring in an individual afflicted with epilepsy, and thought to be a result of prolonged seizures, the epileptogenic brain lesion, or antiepileptic drugs.- paralytic d. d. and paralysis resulting from a chronic syphilitic meningoencephalitis. SYN: d. paralytica.- d. paralytica SYN: paralytic d..- d. praecox any one of the group of psychotic disorders known as the schizophrenias; formerly used to describe schizophrenia as a single entity. [L. precocious]- presenile d., d. presenilis 1. d. of Alzheimer disease developing before age 65; 2. SYN: Alzheimer disease.- secondary d. chronic d. following and due to a psychosis or some other underlying disease process.- vascular d. a steplike deterioration in intellectual functions with focal neurologic signs, as the result of multiple infarctions of the cerebral hemispheres. SYN: multi- infarct d..
* * *de·men·tia di-'men-chə n a usu. progressive condition (as Alzheimer's disease) marked by the development of multiple cognitive deficits (as memory impairment, aphasia, and inability to plan and initiate complex behavior)de·men·tial -chəl adj
* * *n.a chronic or persistent disorder of behaviour and higher intellectual function due to organic brain disease. It is marked by memory disorders, changes in personality, deterioration in personal care, impaired reasoning ability, and disorientation. Presenile dementia occurs in young or middle-aged people. The most common causes of dementia are Alzheimer's disease, frontotemporal dementia (e.g. Pick's disease), and dementia due to diffuse cortical Lewy body disease. Another common form, multi-infarct dementia, results from the destruction of brain tissue by a series of small strokes. It is important to distinguish these organic conditions from psychological disorders that cause the same symptoms (see pseudodementia).
* * *de·men·tia (də-menґshə) [de- + L. mens mind] [DSM-IV] a general loss of cognitive abilities, including impairment of memory as well as one or more of the following: aphasia, apraxia, agnosia, or disturbed planning, organizing, and abstract thinking abilities. It does not include loss of intellectual functioning caused by clouding of consciousness (as in delirium), depression, or other functional mental disorder (pseudodementia). Causes include a large number of conditions, some reversible and some progressive, that result in widespread cerebral damage or dysfunction. The most common cause is Alzheimer disease; others include cerebrovascular disease, central nervous system infection, brain trauma or tumors, vitamin deficiencies, anoxia, metabolic conditions, endocrine conditions, immune disorders, prion diseases, Wernicke-Korsakoff syndrome, normal-pressure hydrocephalus, Huntington chorea, multiple sclerosis, and Parkinson disease.
Medical dictionary. 2011.