The most common form of dementia in older people is Alzheimer’s disease (AD). Dementia is associated with damaged brain tissue and it severely impairs memory and reasoning ability. Alzheimer’s is a disease that is irreversible. It affects as many as 5 million Americans. The disease progressively destroys cognitive functioning, eventually erasing memory and disabling reasoning skills. The majority of Alzheimer’s patients start to show symptoms after age sixty.
Cognitive functions that include thinking, remembering and reasoning are severely compromised in the advanced stages of Alzheimer’s. The disease is extremely slow moving in the early phase. Damage to the brain may occur 10 to 20 years before symptoms become obvious. Alzheimer’s makes its appearance slowly in the entorhinal cortex in the form of tangles, and in plaques in other regions.
Tangles are stringy blobs that are formed by the protein tau. The tau protein is part of maintaining healthy brain cell structure but for some reason they become toxic in Alzheimer’s patients. Normally the body should be able to identify and destroy these toxic cells, but this doesn’t happen in AD.
Plaques are microscopic masses of fragmented axon terminals and dendrites around a core of amyloid.
Healthy nerve cells in the brain (neurons) have support structures called microtubules, which guide nutrients and molecules from the cell’s body down to the ends and back. A special kind of protein, tau, makes the microtubules stable. Tau is changed chemically in people with Alzheimer’s disease. It begins to pair with other threads of tau and they become tangled up together. When this happens, the microtubules disintegrate, collapsing the neuron’s transport system. This may result first in communication malfunctions between neurons and later in cell death.
Healthy neurons get overwhelmed as these plaques and tangles take over brain areas. Eventually these neurons can no longer function properly and die. The damage to neurons spreads to the hippocampus, which is the part of the brain that is necessary for forming memories. AD brains show a large loss of nerve cells (neurons) in the cerebral cortex and somewhat greater in the frontal and temporal areas. The death of these neurons makes the brain shrink.
Signs and Symptoms in The Very Early Stage of Alzheimer’s
The slow dissent into Alzheimer’s begins with memory loss. One type of memory problem is a condition called amnestic mild cognitive impairment (MCI). MCI is present and about 15% of the general elderly population. Having MCI does not mean you will get Alzheimer’s, but more people that had MCI go on to develop Alzheimer’s than people who do not have MCI.
As Alzheimer’s progresses, memory loss gets worse. There’s also a loss in the executive functions like reasoning and multitasking. People who have mild Alzheimer’s may find themselves getting lost more often, getting confused when handling money, not understanding what other people are saying and taking much longer to do simple daily routines like getting dressed. Often there are changes in mood and personality. This is usually when people get diagnosed with the disease.
Moderate Alzheimer’s Disease Signs and Symptoms
Eventually damage to the brain goes into the areas that govern our use of language, sensory processing reasoning and conscious thought. In the moderate stage, confusion and memory loss episodes happen more frequently. Victims start to have trouble recognizing family and friends that they should remember. They may be overwhelmed by new environments or changes to their daily routine. They have a lot of trouble coping with the things that require multiple steps. As more parts of the brain are affected they may experience hallucinations and delusions. Impulsive behavior and signs of paranoia are common in this stage.
Severe Alzheimer’s Disease
In the final stage of Alzheimer’s, plaques and tangles take over most of the brain, shutting down functionality. The severe Alzheimer’s victim is unable to communicate and is completely dependent upon others for every aspect of survival. The victim is bedridden and eventually the brain gives up control of regulating vital functions and the victim dies.
The Causes of Alzheimer’s
What causes Alzheimer’s disease and what can you do to prevent it? There is no cure yet for this horrible disease. Its causes are not well understood. It appears to be a complex series of events that happens in the brain over a very long period of time. There are indications that there is some genetic causes as well as environmental and life factor causes. It seems that cardiovascular exercise and a good healthy lifestyle can reduce your chances of developing dementia.
Genetics and Alzheimer’s
Early onset Alzheimer’s affects a very few people in middle age. Most of these victims carry an inherited genetic defect. This defect is a mutation in one of three genes inherited from a parent.
The vast majority of people with Alzheimer’s have late-onset Alzheimer’s, which usually develops after age 60. People with the APOE e4 gene have an increased chance of contracting Alzheimer’s. 40% of people with late-onset Alzheimer’s carry the APOE e4 gene. But remember, just carrying the gene does not necessarily mean that you will develop Alzheimer’s.
Brain Fitness and Body Fitness
There seems to be a broad misconception that by exercising your brain you can avoid the developing dementia. Many middle aged and older people are busily completing crossword puzzles and other brain teasers in the hopes that by keeping the brain active they will be able to fight off memory loss and more severe cognitive impairments. But there is a growing body of evidence that indicates that these activities do very little to improve overall brain health. Doing puzzles makes you better at doing puzzles, but it doesn’t seem to cross over and produce stronger cognitive functions.
A number of studies indicate that by simply exercising several times a week you can cut your chances of dementia in half. But not all exercises are equal. Simply doing stretching or toning exercises will not give your brain the boost it needs. Walking three times a week for 40 minutes at a time we’ll do you more good than sitting down with puzzle books. The walking does not have to be at a rapid pace and it’s not necessary to get your heart pounding. Regular walking seems to be a great way to promote brain health.
Make sure your older family members get out and walk. If need be, hire a local senior companion to keep that aging loved one on a healthy routine.