Organic brain syndrome is a general term which refers to physical disorders that cause a decrease in mental function, usually not including psychiatric disorders.

Alternative Names

OBS; Organic mental disorder; Chronic organic brain syndrome

Causes, incidence, and risk factors

OBS is a common "diagnosis" of the elderly. It is not an inevitable part of aging, however. OBS is not a separate disease entity, but is a general term used to categorize physical conditions that can cause mental changes . Disorders associated with OBS include, but are not limited to:

Degenerative disorders:

Creutzfeldt-Jacob disease

Huntington disease

Multiple sclerosis

Normal pressure hydrocephalus

Pick's disease

Senile dementia/Alzheimer's type

Cardiovascular disorders

:

Arrhythmias

-- may cause some types of OBS

Cardiac infections (

endocarditis , myocarditis , etc.) -- may sometimes cause OBS

Hypertensive

brain injury

Multi-infarct dementia

(multiple strokes)

Stroke

TIA

Trauma-induced brain injury:

Chronic subdural hematoma

(blood clot causing pressure on brain)

Concussion

Intracerebral hemorrhage

Subarachnoid hemorrhage

Dementia due to metabolic causes

Respiratory

conditions -- may cause or aggravate OBS

Hypoxia

(decreased oxygen in the body)

Hypercapnia

(increased carbon dioxide levels in the body)

Infections

Any

acute or chronic infection

Septicemia

(presence in the bloodstream of toxic by-products caused by infection)

Meningitis

Encephalitis

Drug and alcohol related conditions

Intoxication,

drug abuse , or alcohol use

Long-term effects of alcohol,

Wernicke-Korsakoff syndrome

Alcohol withdrawal state

Withdrawal from drugs (especially sedative-hypnotics and corticosteroids)

Parkinson's disease

Other conditions that may be related to organic brain syndrome include:

depression , neuroses, and psychoses of various types, which may occur simultaneously with the OBS.

Signs and tests

Testing and physical examination vary depending on the specific disorder.

Treatment

Treatment varies with the specific disorder. Many of the disorders have nonspecific treatments -- primarily supportive care to assist the person in areas where brain function is lost. Medications may be needed to reduce aggressive behaviors typical of some of the conditions in this category.

Expectations (prognosis)

See the specific disorder. Some disorders are acute and treatable, but many are chronic or progressive.

Complications

Loss of ability to interact or function independently is common.

Calling your health care provider

Call your health care provider if "organic brain syndrome" has been diagnosed and you are uncertain of the actual, specific diagnosis; if you have symptoms which suggest this problem; or if you have been diagnosed with it and symptoms become worse.