Ask an Expert about Alzheimer's Disease

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.

Familial Alzheimer’s disease (FAD) or early-onset Alzheimer’s 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.

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.

When Alois Alzheimer observed the brain of a patient affected by the disease that later was named after him, he sketched two characteristic microscopic abnormalities that continue to be the focus of modern research. Within many brain cells (neurons), he saw tangles of the internal neurofibrils (microtubules) that represent a disruption of the normal intracellular transport system. These tangles result when chemical changes (hyperphosphorylation) are made to a protein (tau protein) that otherwise serves to stabilize the microtubules. When tau protein is altered, as in Alzheimer’s disease, the microtubules collapse into a tangled clump that no longer properly transports nutrients within the cell. Other diseases in which disordered tau protein is important (the “tauopathies”) include Pick’s disease, corticobasal degeneration, and progressive supranuclear palsy. Several new therapies under investigation aim to treat Alzheimer’s disease by stabilizing tau proteins.

Dr. Alzheimer also noted intracellular clumps of material that he called “military foci.” Later investigations have shown these “plaques” to consist of aggregated “beta-amyloid” and inflammatory reactive changes. Beta-amyloid is the name given to a family of polypeptides (chains of amino acids, which are the building blocks of proteins) that result from the enzymatic snipping of protein fragments off of a larger protein (Amyloid Precursor Protein) embedded in the membranes of neurons. These fragments, called oligomers, vary in length from 39 to 43 amino acids and the fragment that is 42 amino acids long (Aβ42) is particularly damaging to brain cells. Both in the blood-borne oligomer form and in intercellular plaques in the brain, Aβ42 is believed to cause much of the damage associated with Alzheimer’s disease. Many Alzheimer’s disease medications in current development, therefore, aim to decrease the presence of Aβ42 in the bloodstream and/or brain. Amyloid is considered important not only in Alzheimer’s disease but also in Lewy body dementia, inclusion body myositis (a muscle disease), and cerebral amyloid angiopathy (a disease of the blood vessels in the brain).

Modern neuroimaging techniques have demonstrated great promise in making possible the earlier diagnosis of Alzheimer’s disease. Early signs of beta-amyloid accumulation in the brain, for example, can be identified through the use of Positron EmissionTomography (PET) scans along with a technique that uses radioactively labeled tracer molecules to find where amyloid concentrations are elevated in the brain.

There are some very good reasons to strive for an early diagnosis of Alzheimer’s. Early diagnosis may help a person and his or her support system understand confusing changes in function and behavior, and research has shown that education of families increases the success of treatment and home residence. Furthermore, early identification of Alzheimer’s disease allows a person and support system to plan ahead regarding such potential concerns as medication adherence, safety (for example with driving, stove use, or wandering), advance planning for a time when the person may no longer be competent to make prudent decisions (testament, power of attorney, advance directives), and whether or not to volunteer for studies investigating potential new treatments (many of which are tested in the early phases of disease process). In time, it is hoped that treatments will be available that will be particularly beneficial in the disease’s early stages.

An important caveat with early diagnosis, however, is that it must be very accurate and reliable! The potential consequences of assigning an incorrect Alzheimer’s disease diagnosis could be devastating.

Epilepsy is a disease characterized by recurrent disordered electrical signals in the brain, resulting in seizures. Seizures are typically brief episodes of disordered brain functioning that may appear as changes in consciousness, muscle activity, or autonomic functioning. Some cases of epilepsy have no clearly identifiable cause, but many seizures are attributable to a specific factor, such as withdrawal from alcohol. Seizures are seen in up to one fifth of Alzheimer’s disease patients, and typically these seizures occur in patients with early-onset disease and/or in the later stage of the disease. Often these seizures are described as “seizures secondary to Alzheimer’s disease” rather than as epilepsy, though they could be considered a “secondary epilepsy” (an epilepsy attributable to a specific cause). When seizures occur in an Alzheimer’s disease patient, it can be valuable to examine further with neurological assessment, an imaging study such as an MRI, and an electroencephalogram (EEG) in order to see whether there is a stroke or other non-Alzheimer’s contributing factor. If an anti-seizure medication is used, it’s important to recognize that these medications sometimes affect cognition.

While it remains unclear whether depression actually causes Alzheimer’s disease, the occurrence of depression and depressive symptoms is noticeably quite frequent among people with dementia. Several recent studies have suggested that depression may be a predictor or even a risk factor for the onset of Alzheimer’s disease. For example, studies have indicated a correlation between depression and Alzheimer's disease, wherein a history of depression (particularly in patients under the age of 60) is associated with a greater risk of developing this neurological disorder. Researchers believe that depression—particularly long-term untreated depression—may change the brain’s overall chemistry, making it more vulnerable to insults and neurodegeneration. Further research is clearly needed to confirm these conclusions.

You can read more about the association between depression and Alzheimer’s disease in the following articles:

Apathy and Depression Predict Progression From MCI to Dementia

Depression May Nearly Double Risk of Dementia

Because of the progressive degenerative nature of Alzheimer’s disease, most all areas of the brain are eventually affected by the disease. Typically, the brain areas concerned with memory, cognition and perception are affected first, followed by brain regions involved in speech, movement and bodily functions. Of course, this progression is different for each person, and that is why no two people experience the same exact symptoms at the same time. In your wife’s case, the disease has advanced to the point where it is now clearly affecting her ability to walk, eat and speak. Based upon your description, therefore, it would seem that your dear wife is in late-stage Alzheimer’s disease (stage 3 according to our scale, and stage 7 according to other clinical scales). This stage typically may last for 1 to 3 years.

In the later stages of Alzheimer’s disease, a person can become immobile. Your wife’s inability to stand may therefore be directly related to the progression of the disease, or it could be caused by another unrelated condition altogether. Unfortunately, in these neurodegenerative diseases, it is sometimes impossible to clearly pinpoint which disease causes which ailment. Regardless, it is important that her position (be it sitting or lying down) is changed regularly to prevent sores from developing. Also, to the best of her ability, try to encourage your wife to do some stretches and arm and leg lifts from a seated position. You will have to help guide her in the movements, but just go slowly and let her try to do as much as she can on her own. The goal is to keep her muscles active to slow muscle deterioration. Any physical activity is good—it does not need to be rigorous and it is actually better if she does not overexert herself.

When an Alzheimer’s patient becomes unable to communicate, it is essential to continue to provide him or her with human contact in any form. Even though it may seem as if your wife cannot hear or respond to you, you presence near her is likely a calming influence. Many caregivers are certain that some of what they say in the presence of their non-communicative loved ones gets through. So continue to talk to her and tell her you love her. Also, don’t forget about non-verbal communication. Touch is very important too, so hold her hand, gently stroke her arm or brush her hair, or give her a gentle shoulder massage. It may not seem like much to you, but these little things can improve her mood and affect her overall well-being.