neurologic disorders
Dementia
Introduction
Dementia is chronic, global, usually irreversible deterioration of cognition. Diagnosis is clinical; laboratory and imaging tests are usually used to identify treatable causes. Treatment is supportive. Cholinesterase inhibitors can sometimes temporarily improve cognitive function. (See also Overview of Delirium and Dementia .) Dementia may occur at any age but affects primarily older people. It accounts for more than half of nursing home admissions. Dementias can be classified in several ways; one way is Alzheimer or non-Alzheimer type Cortical or subcortical Irreversible or potentially reversible Common or rare Overview of Delirium and Dementia should not be confused with Dementiaaffects mainly memory, is typically caused by anatomic changes in the brain, has slower onset, and is generally irreversible. Deliriumaffects mainly attention, is typically caused by acute illness or drug toxicity (sometimes life threatening), and is often reversible. Other specific characteristics also help distinguish the two disorders (see table). 