An update on biological treatment of behavioral and psychological signs and symptoms of dementia

In addition to cognitive deficits, dementia is characterized by noncognitive behavioral disorders that are highly prevalent as the disease progresses into its later stages. These behavioral and psychological signs and symptoms of dementia, are probably more important on a day to day basis than the cognitive deficits : in some patients, they are not a source of major disability but rather just a nuisance and may not require active pharmacological treatment; in others, they can be source of substantial anxiety and distress. Among the many behavioral symptoms of dementia, the group of behaviors included under the label of depression, anxiety, agitation aggressiveness or uncooperativeness are the most burdensome and frequently lead to the prescription of an antipsychotic drug. They often precipitate institutional placement. The rationale for the use of psychotropic drugs is partially based upon phenomenological similarities of some behaviors observed in elderly demented patients to signs and symptoms of psychiatric disorders such as depressive illnesses, anxiety or psychotic disorders in nonelderly patients. In fact, the << psychiatric symptoms >> in Alzheimer's disease or other dementia are often qualitatively different from those that caracterize depressive, anxious or psychotic disorders. Many monoaminergic acquired deficits in dementia may also explain why treatment outcome studies suggest that the psychotropic drugs are less effective in patients with Alzheimer's disease or frontal lobe dementia than in patients with psychiatric disorders. The role of cholinesterase inhibitors in the treatment of neuropsychiatric symptoms in Alzheimer's disease may represent a novel and promising therapeutical approach.