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Johns Hopkins Symptoms and Remedies

Johns Hopkins Medicine

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Alzheimer's Disease

What is it?

Alzheimer's disease results from the gradual degeneration of nerve cells (neurons) in the parts of the brain that process cognitive information. Symptoms usually appear very slowly, get progressively worse over years, and are irreversible. Minor forgetfulness becomes more pronounced; speech deteriorates; and the ability to do everyday things, such as dressing, bathing, and eating, is increasingly difficult. In the final stages, severe cognitive impairment results in complete dependence upon caregivers. On average, patients die within 10 years of onset, often from complications such as malnutrition or pneumonia. Alzheimer's disease affects about 10 percent of people over the age of 65, more than 10 percent of those between 75 and 85, and by some estimates, upward of 50 percent of those over 85.

What Causes It?

  • Good evidence indicates that a genetic component predisposes some individuals to Alzheimer's disease, but there are likely several distinct causes. The mechanism of the disease is characterized by the death of neurons in certain areas of the cerebral cortex of the brain, especially those in which integration of new information and retrieval of memory take place.
  • In people with Down syndrome, Alzheimer's disease occurs at an earlier age.

Prevention

  • There is no proven way of preventing Alzheimer's disease.

Diagnosis

  • Except for an autopsy, no test or examination can definitively identify Alzheimer's disease. Instead, diagnosis is based on patient history (including input from family members) and clinical examination, including a test of mental status. The primary criterion is gradual loss of memory and other cognitive functions. Other disorders that can cause dementia must be ruled out; this may be facilitated by imaging of the brain and various laboratory tests, including:
  • MRI (magnetic resonance imaging) or CT (computed tomography) brain scans to rule out cancer, subdural hematoma (a collection of blood), adult hydrocephalus (an accumulation of spinal fluid), or multiple small strokes due to vascular disease.
  • Blood tests to rule out vitamin deficiencies, endocrine disorders (such as hypothyroidism), syphilis, HIV, and heavy-metal poisoning.

How to Treat It

  • Donepezil (Aricept), galantamine (Reminyl), and rivastigmine (Exelon), inhibitors of the enzyme acetylcholinesterase, provide modest improvement in some patients with mild to moderate Alzheimer's disease. Side effects include nausea and loss of appetite.
  • Insomnia, depression, aggression, and other psychological manifestations may be treated with various medications.
  • Much of the responsibility to care for a patient with Alzheimer's falls into the hands of the primary caregiver. Supportive counseling, day care, visiting nurses, and eventual inpatient nursing facilities may help to ease the caregiver's burden. Contact your local chapter of the Alzheimer's Association for further information.

When to Call a Doctor

  • Occasional forgetfulness, such as misplacing the car keys, is normal and rarely anything to worry about. However, consult a doctor if you or a family member begins to show increasing signs of memory lapses; becomes lost in a familiar place; loses the ability to do everyday activities; or undergoes a change in personality.