The Alzheimer's Epidemic. Danton O'Day

Чтение книги онлайн.

СКАЧАТЬ carried out in conjunction with other questionnaires that assess behavior, quality of life as well as the ability to function in the real world. Questionnaires can also be given to reveal the burden that is put on caregivers who are responsible for looking after those suffering from delusional behaviors.

      The accumulated research reveals that delusions arise due to the deterioration of the frontal lobe of the brain. Poor frontal lobe functioning is also linked to impaired activities in the Alzheimer’s individual’s daily life. CT (Computerized Tomography) scans show more lesions in frontal lobe white matter in delusional sufferers compared to normal individuals. PET (Positron Emission Tomography) studies show a reduced uptake of glucose in the frontal lobe of individuals with delusional behavior caused by Alzheimer’s disease. The sugar glucose is an energy source for cells and a reduced uptake by neurons signals their decreased energy needs. This in turn indicates that these cells are less functional than normal brain cells. As if this weren’t enough, delusional Alzheimer’s individuals also show increased levels of amyloid plaques in their frontal lobes. These and other aspects of the Alzheimer’s brain are discussed in Chapter 4 as well as elsewhere throughout the book.

      With dementia, individuals progressively lose their ability to respond to the world around them. They become unable to perform the normal activities of daily life or to simply carry on a conversation. They often fail to recognize loved ones or remember who they are. This loss of cognitive awareness likely underlies many of the symptoms of the dementia stage of Alzheimer’s disease where increased levels of panic and anxiety are not uncommon. Hypochondria is common in about 30% of dementia individuals. So too are increases in obsessive behavior, paranoia and depression. One study revealed that around 40% of dementia sufferers experienced one or more of these behavioral symptoms. Around 13% of individuals ultimately become antisocial while over 20% exhibit schizoid behavior. Some can become violent. Of all of these behaviors, schizoid and paranoid tendencies increase the greatest degree in the progression from MCI to dementia. Family caregivers usually are no longer able to care for the Alzheimer’s sufferer by the dementia stage. Full-time care is required which often is only available in a long-term care home.

      It is critical to reiterate that the severity of MCI is not a 100% predictor of progression to dementia. Not all MCI individuals will suffer from dementia. It has been estimated that about 15% of people with MCI progress to the dementia stage per year. In one study, 25% of the MCI group had not progressed to dementia even after 10 years. Currently, there is no way to determine which MCI individual will progress to full-fledged dementia.

      Types of Dementia

      What exactly is dementia? Dementia is an all-inclusive term that describes a variety of conditions and diseases that result from abnormal neuron function and/or death. Alzheimer’s is the most common form of dementia. Your doctor might use criteria provided by the Diagnostic and Statistical Manual of Mental Disorders to determine if dementia exists. These criteria include a decline in one’s memory along with one or more symptoms from a list.

      This list includes:

      •The ability to produce coherent speech;

      •The ability to understand spoken language or written words;

      •The ability to identify objects;

      •The ability to think in an abstract way or to make sound judgements;

      •The inability to function properly in daily life;

      •The ability to plan and carry out complex tasks; and,

      •The ability to carry out motor activities.

      In addition to Alzheimer’s disease, there are seven other common types of dementia that are summarized in Table 3.1.

      Several dementias have Alzheimer’s disease-like symptoms and this is why it is important for proper diagnostic tests to be carried out so that a disease-based therapeutic approach can be started. There are two other types of dementia listed in Table 3.1 that should be addressed as well. The extensive news coverage of “Mad Cow Disease” led many to be leery of eating beef. Mad cow disease is a prion-based disease. Prions are proteins that have misfolded. When they enter the body, prions induce proteins that are folded normally to misfold, thus interfering with normal cellular function. In the brain this leads to miscommunication between neurons and neuron death observed as holes in the brain.

      A second common cause of dementia is linked to the presence of Lewy bodies in the brain. Lewy bodies are precipitates or accumulations that are rich in the protein alpha-synuclein. They cause Parkinson’s disease and dementia linked to Lewy bodies. Alpha-synuclein makes up as much as 1% of the protein in brain neurons. Lewy bodies are fundamentally similar to amyloid plaques except the former consist of deposits of the protein alpha-synuclein while the latter are made up of amyloid beta. In addition, Lewy bodies form inside of neurons while amyloid plaques form outside of them. When they do appear, Lewy bodies interfere with nerve cell organization and function leading to malfunction of nerve cell communication, which underlies the dementia that is observed.

      Table 3.1. Common types of dementia.

      It is important to realize that certain other conditions can result in symptoms that mimic dementia. These conditions include depression, drug use, excessive use of alcohol, side effects from medications, thyroid problems and certain vitamin deficiencies, to name the most common. When those conditions are removed or corrected then the dementia-like symptoms disappear.

      The Three Stages of Dementia

      While the progression of dementia varies greatly from individual to individual, the World Health Organization (WHO) and other groups define three stages. Each of these stages falls within a relatively regular timeframe and each has specific characteristics. Here we will summarize the approximate timing and specific symptoms of each stage. These stages apply not only to Alzheimer’s disease, the most common cause of dementia, but also to other neurodegenerative diseases such as dementia with Lewy bodies and vascular dementia, among others.

      The three stages of dementia are the following:

      •Early stage—occurs within the first year or two;

      •Middle stage—occurs during year two to five;

      •Late stage—occurs from the fifth year onwards.

      The following Table summarizes some of the signs and symptoms of each of the three stages of dementia (Table 3.2).

      Table 3.2. The three stages of dementia.

      Thus it can be seen that early on, most people will discount many of the early-stage signs and symptoms of dementia as simply a reality of the aging process. After all, as we age we all are a bit forgetful, some more than others. We all find certain words or names elusive and may forget what day it is, especially if we are retired. It is not unusual for people at any age to show phases of anger, anxiety and depression. But when these mood changes and behaviors increase or appear in a person who normally doesn’t experience them, it is time for concern. Also, when these basic signs are coupled with several other symptoms, they may be due to the early stage of dementia.

      Dementia is progressive. Though it varies from person to person, the initial attributes of early-stage dementia become increasingly more pronounced СКАЧАТЬ