What treatments are available for Alzheimer's disease?
What treatments are available for Alzheimer's disease?
At present, there is no cure for Alzheimer’s disease. However, there are drugs available that may slow the cognitive decline of the disease and other drugs that may be used to combat the behavioral changes that often occur with Alzheimer’s. There are also some techniques that may help with the sleep disorders that often coexist with the disease. Unfortunately, no drug or other intervention can change the fact that a person with Alzheimer’s disease will eventually lose their cognitive abilities and need to rely on others for care.
Medications to slow the cognitive decline
There are two types of drugs that are approved by the Food and Drug Administration (FDA) to help with the cognitive symptoms of Alzheimer’s disease that include memory loss, disordered thoughts, and other mental declines. These medications work by changing the activity of brain chemicals called neurotransmitters that are used to send messages between neurons. There are two classes of these drugs and each class works by affecting levels of one particular neurotransmitter. Because the two affect levels of different neurotransmitters, they are often prescribed together.
Cholinesterase inhibitors
The cholinesterase inhibitor drugs have been in use for several years as a way to slow down the mental decline of Alzheimer’s disease. The brains of people with Alzheimer’s disease produce smaller than normal amounts of a neurotransmitter called acetylcholine, leading to some of the cognitive deficits of the disease. Cholinesterase inhibitors increase the amount of acetylcholine in the brain by blocking the molecule that has the job of breaking down acetylcholine (called cholinesterase) and making it inactive. When cholinesterase activity is reduced, levels of acetylcholine in the brain increase and this can slow or in some cases even temporarily stop a patient’s cognitive decline.
Cholinesterase inhibitors include donepezil (Aricept), rivastigmine (Exelon), tacrine (Cognex), and galantamine (Reminyl). Donepezil has been approved by the FDA to treat all stages of Alzheimer’s disease, while rivastigmine, tacrine, and galantamine have been approved for treatment of mild to moderate Alzheimer’s disease only. Studies on donepezil also indicate that it may delay the onset of Alzheimer’s for approximately one year in people who have a condition called mild cognitive impairment (MCI). People with MCI have memory impairment that is abnormal for their age but do not yet meet the criteria for mild dementia. The side effects of cholinesterase inhibitors include nausea, vomiting, loss of appetite and increased frequency of bowel movements. Tacrine also may cause liver damage at therapeutic doses so patients starting this drug need to have their liver enzymes closely monitored.
The cholinesterase inhibitors don’t work for everyone with Alzheimer’s disease. Perhaps half of those who try these medications do not notice any improvement in their symptoms. Others may stop taking the medication due to the unpleasant gastrointestinal side effects.
Glutamate antagonists
Memantine (Namenda) is the first drug approved in a new class of Alzheimer’s disease drugs that alter the brain’s response to the neurotransmitter glutamate. Memantine is approved to treat moderate to severe stages of Alzheimer’s. The drug works by protecting neurons from damage that can be caused by high levels of glutamate. Glutamate is an excitatory neurotransmitter, meaning it tends to make neural cells more active. When too much glutamate is released, it can cause neurons to become overactive to the point where they become damaged and die. This process is called “excitotoxicity” and is thought to be one of the reasons that neurons die in Alzheimer’s, especially in the later stages of the disease.
Memantine reduces excitotoxicity by preventing glutamate from over-stimulating neurons. It does this by blocking a receptor called the NMDA receptor that normally receives the glutamate signal. With this receptor blocked, even high levels of glutamate will not cause neurons to die. Memantine is sometimes used in combination with one of the cholinesterase inhibitors to help slow cognitive declines. The most common side effect of this drug is dizziness but it may also increase agitation and delusional behavior in some people.
Vitamin E
Some doctors prescribe vitamin E to help treat Alzheimer’s disease. A large study found evidence that taking vitamin E slightly delayed the progression of the disease and allowed patients to stay independent for longer. Researchers think vitamin E may help slow neural cell death because it is a powerful antioxidant that may help protect neurons from damage. Do not use vitamin E to treat Alzheimer’s unless you are told to do so by a doctor and are under their supervision as the doses required are high and may interact with other medications.
Another study examined whether vitamin E could help slow the development of Alzheimer’s in people with a pre-Alzheimer’s condition termed mild cognitive impairment. That study found no evidence that vitamin E delayed the onset of Alzheimer’s disease.
Treatments for behavioral symptoms
In addition to the cognitive declines that occur with Alzheimer’s disease, there are often several behavioral symptoms. Doctors may prescribe medications or other treatments to help reduce the impact of such behavioral issues which include sleeplessness, anxiety, delusions, agitation, and depression. For caregivers of people with Alzheimer’s disease, these symptoms can be the most worrisome and difficult to deal with.
Treating these behavioral problems without drugs requires first understanding that it is not the patient’s fault they are acting out. Alzheimer’s is a brain disease and the death of brain cells leads to changes in mood and behavior that are difficult for anyone who is not experiencing them to understand. Some methods for dealing with these behavioral issues as suggested by the Alzheimer’s Association follow:
* Monitor the patient’s personal comfort. They may be experiencing something unpleasant but may not be able to communicate about it.
* Try to alleviate possible sources of discomfort such as pain, hunger, thirst, constipation, full bladder, fatigue, infections or skin irritations.
* Avoid confronting them or arguing about facts; instead, respond to the feeling behind what is being expressed.
* Redirect the person’s attention away from unpleasant things.
* Try to remain flexible, patient and supportive.
* Create a calm environment. Avoid noise, glare, insecure space, and too much distraction, including television.
* Simplify tasks that are required of the patient.
* Allow the patient to rest between stimulating events.
* Allow the patient to have some privacy.
* Equip doors and gates with safety locks.
* Remove dangerous objects from the patient’s environment.
Other things you can do include eliminating any external causes of distress that might be upsetting the patient and limiting changes in the patient’s surroundings or routine that may exacerbate behavioral problems. If non-drug approaches fail after they have been applied consistently, it may be appropriate to try medications to alleviate severe behavioral symptoms, especially if these symptoms make the patient more likely to harm themselves or others. Medications should be targeted toward alleviating specific behavioral symptoms. The three basic types of medications that can help are: antidepressant medications for low mood and irritability; anxiolytics for anxiety, restlessness, verbally disruptive behavior, and resistance; and antipsychotic medications for hallucinations, delusions, aggression, agitation, hostility, and uncooperativeness. Talk to a doctor about these medications to determine if they are appropriate for your loved one.
Treatments for sleeping problems
Many Alzheimer’s patients experience changes in their sleep patterns. Researchers are unsure why this happens but the changes are related to the brain changes that accompany Alzheimer’s disease. Sleep issues in Alzheimer’s may include difficulty sleeping, daytime sleepiness, and shifted sleep cycles. These problems tend to get worse as the disease progresses. Experts estimate that in the late stage of Alzheimer’s, individuals may spend up to 40 percent of their time in bed awake and spend a large part of their day sleeping.
An Alzheimer’s patient who is experiencing sleeping problems should see a doctor to rule out any other medical conditions that could be contributing to their difficulty sleeping. If they are depressed or if they have conditions like restless leg syndrome or sleep apnea, these conditions can be treated and it may help them sleep better.
Non-drug approaches to treating sleep problems involve sticking to a sleep routine and improving the sleeping environment to reduce daytime napping. To create an inviting sleeping environment and improve the sleep routine, the Alzheimer’s Association recommends:
* Maintaining regular times for meals, for going to sleep, and for getting up.
* Exposing the patient to sunlight as soon as possible upon waking.
* Getting regular daily exercise.
* Cutting out alcohol, caffeine, and nicotine that may disturb sleep.
* If the patient is taking a cholinesterase inhibitor, avoid giving the medicine before bed.
* Keeping the bedroom at a comfortable temperature (usually a little below daytime room temperature)
* Providing a nightlight.
* Encouraging the patient to use the bed only for sleep; no reading or TV in bed.
There are also drug treatments for sleeping problems but they may be of limited usefulness in Alzheimer’s patients. Talk to a doctor if you want to learn more about these medications.
Last modified February 17th, 2008 2:00pm
