Dementia is a general term that refers to a progressive decline in intellectual ability characterized by memory loss, impaired judgment, deterioration of abstract thinking and language, and personality changes. Symptoms appear gradually so that it may take months or even years before a diagnosis is made.

Dementia should not be confused with age-associated memory impairment, which is a clinical term that refers to the normal forgetfulness that is expected with age (for example, having difficulty recalling a name). Dementia, by contrast, involves problems in multiple areas of cognition (thinking) and results in serious impairment.

Dementia can be irreversible or reversible, but most cases of dementia are irreversible. The most common cause of irreversible dementia is Alzheimer’s disease, which is responsible for about 65 percent of dementia cases. Vascular disease is also a primary cause of irreversible dementia.

Reversible dementia is caused by a number of potentially treatable conditions, which include depression, alcohol abuse, vitamin B12 deficiency, thyroid disease, and side effects of medication. However, despite its label, reversible memory loss is often only partially restored.

Symptoms of Dementia

• Memory loss.

   

• Language impairments.

   

• Difficulty with learning and retaining new information.

   

• Difficulty handling complex tasks.

   

• Impaired judgment.

   

• Getting lost or disoriented in familiar places.

   

• Personality changes, such as becoming more irritable or less responsive than usual.

What Causes Dementia?

• The cause of Alzheimer’s disease is unknown.

   

• Reduced blood flow to the brain, often resulting from a series of tiny strokes (known as infarcts), causes vascular dementia; other causes include chronic high blood pressure, diabetes, or coronary heart disease.

   

• Another irreversible dementia, dementia with Lewey bodies, is caused by abnormal structures within nerve cells that are distributed throughout the brain.

   

• Pick’s disease is the main cause of frontotemporal dementia, in which patients display personality changes and compulsive behaviors.

   

• Irreversible dementia may also be caused by other diseases, which include Parkinson’s disease, Huntington’s disease, and Creutzfeldt-Jakob disease.

   

• Reversible dementias have a number of causes, including alcohol abuse, infections, such as AIDS or neurosyphilis, brain tumors, and reactions to certain medications.

Prevention of Dementia

• Lifestyle measures, such as weight control and exercise, may help forestall the development of vascular dementia; however, most types of irreversible dementia are not preventable.

   

• Drinking alcohol in moderation and eating a balanced diet may help prevent some reversible forms of dementia.

Diagnosis of Dementia

• Diagnosis is based on patient history (including information from family members) and clinical evaluation. Tests of mental status, including reasoning ability, short-term memory, and handling complex tasks, are also given.

   

• Blood tests are used to identify potentially reversible causes of dementia.

How To Treat Dementia

• For reversible dementia, a physician may alter a patient’s medication regimen to remove any medications that may be causing symptoms.

   

• Underlying disorders, such as depression or vitamin B12 deficiency, that may cause reversible dementia should be treated.

   

• The drugs donepezil or rivastigmine improve cognition in about 30 percent to 60 percent of patients with mild to moderate dementia.

   

• Most types of dementia are incurable, and the goal of treatment is supportive care, which includes counseling, day care, home health care, and in-patient nursing facilities.

When To Call A Doctor

• Consult a doctor if you or a family member shows an increasing decline in cognitive abilities or if a person with dementia has a sudden deterioration in their level of functioning.

For more information on dementia and related memory conditions, click on this link -- Johns Hopkins Health Alerts: Memory