Cause
Dementia is caused by damage to or changes in the
brain. After
, stroke is the most common cause of
dementia. Dementia caused by stroke is called .
Some causes of dementia can be
reversed with treatment, but most cannot.
Causes that cannot
be reversed
Common causes of dementia that cannot
be reversed are:
- . Dementia is common in people with this
condition.
- . It can cause short-term memory
loss.
- , a group of diseases that
includes Pick's disease.
- Severe head injury that caused a loss of
consciousness.
- Vascular dementia that may occur in people who have a stroke, long-term high
blood pressure, or severe hardening of the arteries ().
Less common causes of dementia that cannot be reversed
include:
- .
- Leukoencephalopathies, which are diseases that affect the
deeper, white-matter brain tissue.
- Creutzfeldt-Jakob
disease, a rare and fatal condition that destroys brain
tissue.
- Brain injuries from accidents or boxing.
- Some
cases of
(MS) or
(ALS).
- Multiple-system atrophy (a group of degenerative brain
diseases affecting speech, movement, and
functions).
- Infections such as late-stage
. Antibiotics can effectively treat syphilis
at any stage, but they cannot reverse the brain damage already done.
Causes that may be reversible
When dementia is caused by certain treatable problems, the treatment may also help the dementia. These treatable problems include:
- Underactive thyroid gland ().
- deficiency.
- Heavy-metal
poisoning, such as from lead.
- Side effects of medicines or drug
interactions.
- Some brain tumors.
- .
- Some cases of chronic alcoholism.
- Some cases
of
.
- .
Inherited dementia
Some disorders that cause dementia can run in families.
Doctors often suspect an inherited cause if someone younger than 50 has
symptoms of dementia. For more information, see the topic
Alzheimer's Disease.