Alzheimer's Disease FAQs

  • Questions & Answers
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Get the answers to frequently asked questions about Alzheimer's Disease by clicking one of the topics below.


About the Disease

  • Dementia is a decline in thinking, reasoning, and/or remembering. People with dementia have difficulty carrying out daily tasks they have performed routinely and independently throughout their lives. Vascular dementia, a hardening of the arteries in the brain that causes blockage in blood flow, is one of the two most common forms of dementia; the other is Alzheimer's disease. These two conditions account for the vast majority of cases; both are irreversible, although sometimes their symptoms can be managed.

    A doctor can accurately determine whether a person is suffering from Alzheimer's disease or another form of dementia. If a person appears to be losing mental abilities to a degree that interferes with daily activities and social interactions, consult a doctor.


  • The following stages represent the general course the disease follows, but moving from one stage to another may not be perceptible due to the fact that the symptoms are on a gradual continuum of severity.

    Pre-clinical/Pre-symptomatic Stage:

    Physical conditions connected to Alzheimer’s disease exist in a person’s body long before symptoms are evident. These conditions are normally defined through the use of “biomarker” tests, like those searching for beta-amyloid and tau proteins in blood and cerebrospinal fluid, and specialized PET and MRI scans. Currently, this stage is only defined in research settings and clinical trials and is unlikely to be given as an official clinical diagnosis by a health professional.

    Mild Cognitive Impairment (MCI) Due To Alzheimer’s Disease/Prodromal Stage:

    Recently, scientists have identified a condition between normal age-related memory loss and dementia called mild cognitive impairment (MCI). Individuals with MCI have persistent memory problems (for example, difficulty remembering names and following conversations and marked forgetfulness) but are able to perform routine activities without more than usual assistance. MCI often leads to Alzheimer’s, but while all those who progress to some form of dementia go through a period of MCI, not all patients exhibiting MCI will develop Alzheimer’s disease. An official clinical diagnosis of MCI can be given by a health professional.

    Dementia Due To Alzheimer’s Disease (Mild, Moderate, Severe Stages):

    Mild (Stage 1)

    Early in the illness, people with Alzheimer’s tend to lose energy and spontaneity, though often no one notices anything unusual. They exhibit minor memory loss and mood swings and are slow to learn and react. After a while they start to shy away from anything new and prefer the familiar. In this stage, Alzheimer’s patients can still perform basic tasks independently but may need assistance with more complicated activities. Speech and understanding become slower, and patients often lose their train of thought in midsentence. They may also get lost while traveling or forget to pay bills. As they become aware of this loss of control, they may become depressed, fearful, irritable, and restless.

    Moderate (Stage 2)

    Eventually, people with the illness begin to be disabled by it. Though the distant past may be recalled, recent events become difficult to remember. Advancing Alzheimer’s affects the ability to comprehend location, the day, and the time. Caregivers must give clear instructions and repeat them often. As Alzheimer’s patients’ minds continue to slip away, they may invent words and not recognize formerly familiar faces.

    Severe (Stage 3)

    During the final stage, patients become more and more unresponsive. Memory becomes so poor that no one is recognizable. Patients lose bowel and bladder control and eventually need constant care. They lose the ability to chew and swallow and become bedridden and vulnerable to pneumonia, infection, and other illnesses. Respiratory problems worsen, particularly when the patient becomes bedridden. This terminal stage eventually leads to coma and death.


  • The national media made a tragic mistake in labeling Alzheimer's disease as “infectious.”  The issue emerged from a highly regarded series of technical reports that described how a protein related to Alzheimer's disease might move from one cell to a neighboring cell. The word “infect” was used to describe an event that may be happening in a single person's brain. The scientific papers do not suggest that the disease might be able to move from one person to another through normal interactions.

    Catherine Clelland, Ph.D. of Columbia University, worked on one of the studies quoted in the media and has received prior funding from BrightFocus. She explained:

    Our study highlighted that different regions of the brain become altered by Alzheimer's disease over time, through spreading of abnormal tau protein from cells in regions where abnormal tau is initially present, to other, directly connected cells within the brain.  It is important to note that there is no evidence from this work, or those of others in the field, that Alzheimer's disease is infectious, or that people who come into contact with Alzheimer's patients are at risk.

    It is true that, in animal studies, it has been shown that removing portions of an Alzheimer's brain, and surgically implanting it inside a healthy brain, can sicken the previously healthy cells. That is obviously a highly unlikely occurrence in humans. As suggested by Dr. Clelland and others, there is no evidence suggesting that animals or humans living and interacting with one another normally can contract the disease from each other.

    Unfortunately, the media picked up the word “infection” and used it erroneously in their reporting. That term functions as a way of scientifically describing how a protein might move between cells within one person's body.  But the usage of that word has had tremendously negative consequences. It has unnecessarily frightened and isolated many people living with the disease…a disease that is not infectious and not contagious. 

    In contrast, the engagement, exercise, and mental stimulation that might be found in social environments are believed by some scientists to play a positive role in helping lessen the burden of Alzheimer's disease. Patients and families suffering with Alzheimer's disease have been hidden from society for far too long. Quite the contrary, we need people talking about Alzheimer's and interacting with others to help end this terrible disease. 

    Definitions:  “Infectious” is something that can cause disease; “contagious” is passable between people.


  • Familial Alzheimer's disease (FAD) is an inherited, rare form of the disease, affecting less than 10 percent of Alzheimer's disease patients. FAD develops before age 65, in people as young as 35. It is caused by one of three gene mutations on chromosomes 1, 14 and 21. If even one of these mutated genes is inherited from a parent, the person will almost always develop FAD. All offspring in the same generation have a 50/50 chance of developing FAD if one parent has it. 

    The majority of Alzheimer's disease cases are late-onset, usually developing after age 65. Late-onset Alzheimer's disease has no known cause and shows no obvious inheritance pattern. However, in some families, clusters of cases are seen. Although a specific gene has not been identified as the cause of late-onset Alzheimer's disease, genetic factors do appear to play a role in the development of this form of the disease. A gene called Apolipoprotein E (ApoE) appears to be a risk factor for the late-onset form of AD. There are three forms of this gene: ApoE2, ApoE3 and ApoE4. Roughly one in four Americans has ApoE4 and one in twenty has ApoE2. While inheritance of ApoE4 increases the risk of developing AD, ApoE2 substantially protects against the disease.

    Scientists believe that several other genes may influence the development of Alzheimer's disease. Two of these genes, UBQLN1 and SORL1, are located on chromosomes 9 and 11. Researchers have also identified three genes on chromosome 10, one of which produces an insulin degrading enzyme that may contribute to the disease. A gene, called TOMM40, appears to significantly increase one's susceptibility to developing Alzheimer's when other risk factors are present, such as having the ApoE-4 gene. Several recently discovered genes that influence Alzheimer's disease risk are CLU (also called APOJ) on chromosome 8, which produces a protein called clusterin, PICALM on chromosome 11 and CR1 on chromosome 1.

    In October of 2013, an international group of researchers reported on the identification of 11 new genes that offer important new insights into the disease pathways involved in Alzheimer's disease. The new genes (HLA-DRB5/HLA0DRB1, PTK2B, SLC24A4-0RING3, DSG2, INPP5D, MEF2C, NME8, ZCWPW1, CELF1, FERMT2 and CASS4) add to a growing list of gene variants associated with onset and progression of late-onset Alzheimer's.

    Genetic risk factors alone are not enough to cause the late-onset form of Alzheimer's disease, so researchers are actively exploring education, diet and environment to learn what role they might play in the development of this disease.


  • Familial or early-onset Alzheimer's disease is inherited and develops in people between the ages of 30 and 60. If even one of three gene mutations that causes the disease is inherited from a parent, the individual will almost certainly develop Alzheimer's disease. However, less than five percent of patients have early-onset Alzheimer's disease. 

    Late-onset is usually developed after age 60; this is the most common form of the disease. Its cause is not known and no pattern of inheritance has yet been discovered, although clusters of cases are seen in some families. One particular gene carried by about 25 percent of the American population increases the risk of developing Alzheimer's disease, while another carried by a small proportion of the population substantially protects against the disease. Scientists have identified other genes that may influence the risk of contracting the disease, and further research is ongoing. 

    Since genetic risk factors are not enough to cause late-onset Alzheimer's disease, researchers are also studying education, diet, and other factors to see if they play a role in developing the disease.


  • On average, patients with Alzheimer's disease live for 8 to 10 years after diagnosis. However, this terminal disease can last for as long as 20 years.


  • Metals have been implicated in neurodegenerative diseases, although it is unlikely that any are the sole cause. For example, interest in a possible connection between aluminum and Alzheimer's disease arose over 40 years ago, and the toxicity of aluminum has been the subject of much controversy since that time. However, aluminum has never been proven to be a direct cause of Alzheimer's, and increasingly, evidence shows that Alzheimer's disease is likely caused not by one, but by a combination of factors. 

    Zinc, copper and iron have also been implicated in the formation of beta amyloid protein plaques that are part of Alzheimer's disease. Zinc and copper interact with amyloid beta precursor protein (APP) and beta amyloid itself, although their role is not clear. While copper promotes free radical formation, zinc is an antioxidant. However, high levels of zinc may contribute to the aggregation of beta amyloid. One particular way in which copper binds to beta amyloid appears to be toxic. Clearly, further research is necessary to determine the exact role of metals in Alzheimer's disease.

    Read a more detailed article on aluminum and Alzheimer's disease.


  • The overall economic impact is staggering.

    Worldwide dementia care is estimated to cost upwards of US$1 trillion.4 According to the World Bank, that’s roughly the same as the gross domestic product of Pakistan in 2017. According to public financial statements, that is more than the 2017 profits of Apple, J.P Morgan Chase and Berkshire Hathaway combined.

    Alzheimer's is projected to cripple America's healthcare system.

    Total payments for health care, long-term care, and hospice for people with Alzheimer's disease and other dementias are projected to increase from $290 billion in 2018 to more than $1.1 trillion in 2050 (in 2019 dollars). Annual healthcare spending averages $4,500 more for patients with Alzheimer’s than similar patients.

    Data sources


Diagnosis and Treatment

  • While an autopsy can confirm the presence of the disease, skilled physicians can correctly diagnose Alzheimer's disease about 90 percent of the time based on mental and behavioral symptoms, a physical examination, and neuropsychological and laboratory tests. Scientists have recently developed a number of new biomarker and brain scanning techniques that may help to improve diagnosis.

    Mentally, having trouble following instructions, losing one's orientation, displaying poor judgment, and having difficulty managing money, shopping, or driving are all possible symptoms of Alzheimer's disease. 

    The physical exam will usually include a general physical, blood tests, and urinalysis. The doctor can use such test results to eliminate other forms of dementia—for instance, certain vitamins and hormones can provoke symptoms of dementia if they are present in too little a quantity. Brain scans can rule out non-Alzheimer's disease dementia and can reveal structural changes present in Alzheimer's disease.

    The physician will determine whether neuropsychological testing is called for to examine memory, attention, math calculations, language and other intellectual functions.

    The place to start is with one's own physician, who may then suggest specialists to do further testing.


  • Not all short-term memory loss is an early sign of Alzheimer’s Disease (AD). Mild forgetfulness and memory delays often occur as part of the normal aging process. Older individuals simply need more time to learn a new fact or to remember an old one. We all have occasional difficulty remembering a word or someone's name; however, those with AD will find these symptoms progressing in frequency and severity. The difference between normal forgetfulness or age-related memory problems and early signs of Alzheimer’s could be described like this: Everyone, from time to time will forget where they placed their car keys; an individual with Alzheimer's may not remember the purpose of the keys.

    What type of memory does Alzheimer's affect?

    One of the hallmarks of early stage Alzheimer's disease is short-term memory loss. Those with the disease lose the ability to perform routine tasks. Keep in mind that while AD affects memory, but it involves far more than simple forgetfulness. Learn about the progression of Alzheimer’s .

    What causes memory problems besides Alzheimer’s Disease?

    Many conditions can contribute to the development of memory problems and dementia; Alzheimer’s is just one of them. A decline in intellectual functioning that significantly interferes with normal social relationships and daily activities is characteristic of dementia, of which AD is the most common form. Alzheimer’s and multi-infarct dementia (a series of small strokes in the brain) cause the vast majority of dementias in the elderly.

    Other possible causes of dementia-like symptoms include infections, drug interactions, a metabolic or nutritional disorder, brain tumors, depression or another progressive disease like Parkinson's.

    What is mild cognitive impairment?

    Individuals with mild cognitive impairment (MCI) have memory impairment (pronounced forgetfulness), but are able to perform routine activities without assistance. Mild cognitive impairment has been identified as one of several major risk factors for developing Alzheimer’s . While all patients who develop some form of dementia go through a period of MCI, not all patients exhibiting mild cognitive impairment will go on to develop AD.

    What should I do if I or someone I know is experiencing memory loss and I don’t know if it’s normal forgetfulness or dementia?

    If memory loss increases in frequency or severity, makes an impression on friends and family, begins to interfere with daily activities (employment tasks, social interactions, and family chores, for example), seek out qualified professional advice and evaluation by a physician with extensive knowledge, experience and interest in dementia and memory problems.

    Learn more about early signs of dementia and warning signs of Alzheimer’s disease.


  • Yes, while there is no cure for Alzheimer's disease as yet, there are medications that can help control its symptoms and to help manage conditions such as agitation, depression, or psychosis (hallucinations or delusions), which may occur as the disease progresses:

    Cholinesterase Inhibitors

    People with Alzheimer's disease have low levels of a key nerve messenger, called acetylcholine, believed to be important for memory and thinking. Four drugs called cholinesterase inhibitors make more of that messenger available by slowing its breakdown, enabling greater cell-to-cell communication and slowing the progress of cognitive impairment in some patients with early- to middle-stage Alzheimer's disease. The four cholinesterase inhibitors are:

    • Razadyne® (galantamine)
    • Exelon® (rivastigmine)
    • Aricept® (donepezil)
    • Cognex® (tacrine)

    All four have been approved by the Food and Drug Administration (FDA) for early- to middle-state Alzheimer's disease; Aricept is also approved for severe-stage symptoms. Cognex was the first approved cholinesterase inhibitor but is rarely prescribed today due to safety concerns.

    Namenda® (memantine)

    The first FDA-approved drug for moderate to severe Alzheimer's disease, Namenda is thought to protect brain cells by regulating a nerve communication chemical, called glutamate, that is released in great quantities by Alzheimer's-damaged cells. Glutamate is normally involved with learning and memory, but when released in excess by damaged cells, it attaches to “docking sites” called NMDA receptors that in turn accelerate cell damage. 

    Combination Drugs

    Namzaric® is a combination of two drugs mentioned above: memantine (Namenda) and donepezil (Aricept). Namzaric capsules can be opened to allow the contents to be sprinkled on food to facilitate dosing for patients who may have difficulty swallowing.

    Treatment for Mental Illnesses

    People with the later stages of Alzheimer's disease often experience depression, agitation, paranoia, delusions, and/or hallucinations, which can in turn cause screaming, repetitive questions, hoarding, pacing, hyperactivity, and aggressive behavior.

    These symptoms can arise from non-medical triggers as well as medical causes. The former could take the form of a change in the person's environment (a new place to live, a new caretaker, a change in routine) or from frustration at the inability to communicate. If the trigger can be identified, the environment can be modified to change the behavior.

    If non-medical intervention doesn't work, or the patient becomes a danger to himself or others, a physician should be asked to evaluate the need for medical treatment.

    See our factsheets on Treatments for Alzheimer's Disease to learn how these drugs work and some common side effects and Financial Aid for Alzheimer's Disease Prescription Drugs to see if you qualify for financial assistance to pay for your medications.

    Remember: Always consult a physician before taking any medications.


  • There is a test currently available that can identify which forms of apolipoprotein (ApoE) are present in the blood. One form, ApoE4, is associated with an already well-studied condition, heart disease, and appears to increase the risk of developing Alzheimer's as well. However, this blood can only detect whether ApoE4 is present, not if and when the person will develop Alzheimer's. 

    In 2007, researchers at Stanford University published some promising study results in which 18 blood proteins (and resultant chemical signals) were tested to determine the risk of advancement from mild cognitive impairment (MCI) to Alzheimer's disease. In the study, the scientists were able to predict whether the subjects would progress to Alzheimer's with 90% accuracy. However, this study tested a relatively small number of people, and larger studies will need to be undertaken.


  • A patient in the final stages of Alzheimer's disease is unlikely to be aware of her state, and therefore is not suffering emotionally. Sometimes occasional moments of lucidity can occur in such a patient, though this is rare. If your loved one does ever become lucid enough to become aware of her condition, she most likely would also be able to communicate with you that time.


  • If you visit a new doctor, bring your medical records; for any doctor, bring a list of over the counter and prescription medicines you are currently taking. If you don't know the names of the drugs, bring the pill bottles with you. A medication or a combination of medications can sometimes cause symptoms that resemble Alzheimer's disease. Also make a list of current medical problems. It's a good idea to show the doctor a list of symptoms, behaviors, and any problems carrying out routine activities (for example, paying bills) in yourself or your loved one that concern you.


  • First, visit your regular family physician. The physician will probably do a variety of tests to determine the probability of Alzheimer's. Specialists such as neurologists, gerontologists and geriatric psychiatrists may also be involved in the evaluation process.


Additional Information

  • Medicare is a federal health insurance program for people age 65 or older who receive Social Security retirement benefits. To receive assistance from Medicare, a person must meet specific eligibility requirements. Medicare covers some, but not all, of the services a person with Alzheimer's disease may require. For example, the program does not cover long term healthcare. Medicaid is a federal program for certain individuals and families with low incomes and resources, typically administered by state agencies; eligibility and benefits vary from state to state. Medicaid can cover all or a portion of nursing home costs. A person with Alzheimer's can qualify for long term care only if there are minimal income and cash assets. Medicaid may be applied for by calling each state's Department of Human Services or Medicaid Assistance Program.


  • BrightFocus’ Alzheimer's Disease Toolkit goes into greater depth on many topics and covers additional areas of concern, both medical and social. You can learn where to get help and access to disease information and resources in our Experts & Advice and Facts & Data sections. 

    See our Helpful Resources for a list of specific organizations about the topics below:

    • General Information, Resources, and Referrals
    • State and Local Resources
    • Caregiving and Caregiver Support
    • Safety
    • Government Programs
    • Legal Assistance
    • Long-Term Care and Living Options
    • Research and Clinical Trials
    • Hospice Care


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