Ask an Expert about Alzheimer's Disease

The human body is able to go for as long as eight weeks without food, so long as adequate water is taken. Without water, life is unlikely to persist longer than five days. Overall health, activity level, and climate are among the factors that can affect these estimates.

Fluctuation of cognitive functioning definitely can occur with Alzheimer’s disease, though it’s even more common with Lewy Body dementia.  In many cases, such sudden behavioral and emotional changes are due to medical conditions such as a urinary tract infection or unrecognized pain difficulties.  If the person you are describing is driving a car when very cognitively impaired, I hope you’ll consider obtaining a formal driving evaluation or taking this potentially dangerous driver off the road for his or her own safety as well as that of others.

Researchers have evaluated more than 50 reports from consumers and health care providers regarding the relationship between statins and memory. Indeed, there are reports of amnesia with these cholesterol-lowering medications.  Some scientists attribute the memory complaints to the lowering of cholesterol while others attribute memory problems in these patients to other effects of the statins themselves.  Memory problems are usually reversible once the statin is stopped, and they are probably infrequent; however, there have been complaints of persistent memory loss. Whether global and persistent amnesia can be caused by statins is still an area of controversy.  Interestingly, epidemiologic evidence suggests that taking statins in midlife to control cholesterol reduces dementia risk later in life.  There is no convincing evidence, however, that taking statins in later life improves cognition.

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 child 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.

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.

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.

Sources for financial assistance for Alzheimer's disease prescription drugs can be found at www.brightfocus.org/alzheimers/resources/alzheimers-disease.html. Always consult a physician before taking any medications.

Aricept (donepezil), an Alzheimer's disease treatment appears to have a slowing effect—though limited—on the progression from mild cognitive impairment (MCI) to Alzheimer's disease, according to a study published in April 2005 by the New England Journal of Medicine. Those with MCI, such as the study participants, experience memory problems, but are able to function independently; however, MCI is often a transitional stage that leads to the serious cognitive decline of Alzheimer's disease. Over the first year of the three-year trial, MCI patients treated with Aricept had a reduced risk of progressing to Alzheimer's disease compared to patients who took a placebo, an inactive pill. The study found the effect of the Aricept treatment lasted longer (up to two to three years) in those patients carrying the ApoE4 gene. Previous studies have shown that those with the ApoE4 gene have a higher risk of developing Alzheimer's than the general population. Source: Mayo Clinic, Rochester and the National Institute on Aging

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.

In terms of health care expenses and lost wages of both patients and their caregivers, the cost of Alzheimer's disease nationwide is estimated to be $100 billion per year. The yearly cost of caring for one Alzheimer's patient ranges from $18,400 to $36,100 depending on the stage of the disease. The average direct cost of caring for an Alzheimer's patient from diagnosis to death is $174,000. According to MetLife market surveys, on average, home health aides cost $19 per hour, the annual cost for an assisted living facility is $34,860, and the daily cost of a private room in a nursing home is $203, which calculates to $74,095 per year.