Alzheimer’s

These tests are used to diagnose Alzheimer’s disease or to rule out other medical conditions that cause symptoms similar to Alzheimer’s disease:

Medical history. The physician will ask about current and past medical conditions, medications the patient is taking, and family history of Alzheimer’s disease or other memory disorders. He or she will also check all current vital signs (blood pressure, heart rate, temperature, pulse rate) and conduct a neurologic exam (check reflexes and coordination, eye movement, speech and sensation).

Blood and urine tests. These are standard lab tests conducted to rule out other causes of symptoms including blood counts, vitamin levels, liver and kidney function, mineral balance, and thyroid gland function tests.

Mental status testing. These tests include tests of memory, problem solving, focus, counting, and language skills. This type of testing can also monitor the progress of Alzheimer’s disease.

Neuropsychological testing. This exam includes tests to assess attention, memory, language, the ability to plan and reason, the ability to change behavior, as well as personality and emotional stability. This type of testing can also monitor the progress of Alzheimer’s disease.

Spinal tap. Also called a lumbar puncture, this test checks for the tau and amyloid proteins that form the plaques and tangles seen in the brains of people with Alzheimer’s disease.

Brain imaging tests:

Computed tomography (CT). This scan reveals physical changes in the structure of brain tissue seen in the later changes of Alzheimer’s disease, including decrease in the size of the brain (atrophy), widening of the indentations of the brain tissues, and enlargement of the fluid-filled chambers of the brain.

Magnetic resonance imaging. This scan can also show brain atrophy. In addition, it can identify strokes, tumors, the buildup of fluid on the brain, and other structural damage that can cause symptoms similar to Alzheimer’s disease.

fMRI (functional MRI). This is a type of MRI that measures brain activity in a select area by detecting changes in blood flow. This test is being used by researchers to see how the brain changes at different stages of Alzheimer’s disease. It is also being used to evaluate treatments for Alzheimer’s disease before a person has symptoms.

Positron emission tomography. This scan shows the abnormal brain activity in a person affected by Alzheimer’s disease. It can also help diagnosis Alzheimer’s disease versus other forms of dementia.

Amyloid PET. This scan shows the buildup of amyloid protein in the brain.

FDG PET. This scans shows how well brain cells use glucose. A decline in the absorption of glucose is a sign of Alzheimer’s disease.

There is no cure for Alzheimer’s disease, but available medications temporarily slow the worsening of dementia symptoms and help with behavioral problems that may appear during the course of the disease.

Four medications representing two drug classes are currently approved by the Food and Drug Administration (FDA) to treat the symptoms of Alzheimer’s disease. These drugs are the cholinesterase inhibitors and a NMDA antagonist.

Cholinesterase inhibitors. The cholinesterase inhibitors are all approved to treat the symptoms of mild to moderate Alzheimer's disease (AD). Cholinesterase inhibitors include:

Donepezil (Aricept®) (also FDA-approved to treat moderate to severe disease)

Rivastigmine (Exelon®) and Exelon patch

Galantamine (Razadyne®)

These drugs work by blocking the action of acetylcholinesterase, the enzyme responsible for destroying acetylcholine. Acetylcholine is one of the chemicals that helps nerve cells communicate. Researchers believe that reduced levels of acetylcholine cause some of the symptoms of Alzheimer's disease. By blocking the enzyme, these medications increase the concentration of acetylcholine in the brain. This increase is believed to help improve some memory problems and reduce some of the behavioral symptoms seen in patients with Alzheimer’s disease.

These medications do not cure Alzheimer’s disease or stop the progression of the disease. The most common side effects of these drugs are nausea, diarrhea, and vomiting. Some people may have loss of appetite, insomnia or bad dreams.

NMDA antagonist. Memantine (Namenda®) is approved by the FDA for treatment of moderate to severe Alzheimer's disease. It blocks the neurotransmitter glutamate from activating NMDA receptors on nerve cells, keeping the cells healthier. This medication works differently than the cholinesterase inhibitors. Memantine can be taken alone or taken together with a cholinesterase inhibitor.

Patients with moderate to severe Alzheimer's who were treated with memantine performed better in studies measuring the common activities of daily living such as eating, walking, toileting, bathing, and dressing compared with patients taking placebo. Patient with lower functioning may benefit the most.

Summary of medications to treat the symptoms of Alzheimer’s disease. The four current medications approved for Alzheimer’s disease have shown modest effects in preserving brain function. They may help lessen or stabilize the symptom of Alzheimer’s disease for a period of time. Due to the side effects of these drugs – especially the gastrointestinal effects -- doctors and patients should talk about their use before prescribing them. Also, these drugs should be stopped when dementia reaches advanced stages.

Managing behavior changes. Medications are available to treat some of the common behavioral symptoms of Alzheimer’s disease. For example, antidepressant drugs can be used to treat anxiety, restlessness, aggression and depression. Anti-anxiety drugs can be used to treat agitation. Anticonvulsants are sometimes used to treat aggression. Antipsychotics can be used to treat paranoia, hallucinations, and agitation. Some of the side effects of these drugs include confusion and dizziness, which can increase the risk of falls. Therefore these drugs are typically used either for short periods of time, only when behavioral problems are severe, and only after safer and/or other non-drug therapies have been tried first.

What newer medications are under study?

All currently approved medications target Alzheimer’s disease after it develops. Scientists are currently researching ways to stop or slow the progress of Alzheimer’s disease before it starts.

Some of the drugs in late-stage investigation are called monoclonal antibodies. These drugs target the amyloid protein that builds up in brain cells. They work by attaching to the amyloid proteins as they float in the brain and remove them, before they form into the plaques and tangles that interfere with the brain’s ability to properly function.

These drugs are still in clinical trials and are several years away from Food and Drug Administration approval in the United States. Early results have been mixed, with some trials showing no improvement in brain function; others showing a slight improvement (less brain function decline). Despite the mixed results, researchers are excited about this new potential method to modify the disease process