Alzheimer's Disease
Degenerative Changes in Alzheimer's Disease
Alzheimer's disease is a type of dementia (a progressive, degenerative brain disease) that leads to memory loss, impaired thinking, and personality changes. After the onset of symptoms, a person with Alzheimer's may live from two to twenty years, during which time their dependence on others increases.
Alzheimer's disease is the most common form of dementia, primarily affecting people over the age of 65, with the risk increasing with age.
About 10% of people with Alzheimer's disease have the early-onset form, which typically develops in their 40s and 50s and is hereditary.
Significant progress has been made in understanding the causes of Alzheimer's disease, although this progress has not yet led to successful treatments. A combination of brain cell death and the depletion of the neurotransmitter acetylcholine is responsible for the symptoms of Alzheimer's disease. One of the main causes of cell death is a protein called beta-amyloid. When this protein is not made properly by brain cells, the cells are damaged, especially in areas of the brain crucial for memory and thinking. Many other proteins, such as prescinelines, which are made within brain cells or transported to the brain from other parts of the body (including a protein called apollipin E4), may also increase the risk of Alzheimer's disease, possibly through their effect on beta-amyloid.
Symptoms
Progressive memory loss is a key sign of Alzheimer's disease. Initially, the impairment is in short-term memory, and the person appears very forgetful. This can affect their ability to interact socially and perform their job. They may be able to recover long-term memories, often in great detail, but eventually, their memory fades as the disease progresses.
Cognitive abilities—higher-order thinking skills such as logical reasoning, decision-making, and judgment—steadily worsen. The change may be subtle. A person with Alzheimer's may find it difficult to perform activities they once did well. Impaired judgment can lead to accidental injuries.
In the early stages of the disease, people with Alzheimer's may lose track of time. Later, their disorientation becomes more pronounced, extending to places and people. Eventually, they may not recognize family members, or even themselves in a mirror. Over time, they forget how to perform basic skills like dressing or eating.
Mood swings and personality changes are often the strongest indicators for families that something is wrong. Depression is common and may stem from the chemical changes in the brain caused by the disease, as well as the psychological reaction to the loss of cognitive abilities.
Those who were once cheerful and outgoing may become increasingly withdrawn, isolated, irritable, or stubborn. Over time, they become inexplicably aggressive, resist their caregivers, refuse to give up unsafe activities, shout obscene words, exhibit inappropriate sexual behavior, urinate in inappropriate places, and so on. In some people, symptoms worsen toward the end of the day, a condition known as "sunset mode."
It is impossible to predict precisely how Alzheimer's disease will affect each individual, as symptoms and their rate of progression vary widely. Some people develop severe psychological problems, while others do not. Some symptoms may appear early, while others may not appear at all. For most people, the decline is slow and gradual, occurring over ten years or more. In rare cases, a person may experience a rapid decline leading to death within three years.
Treatment Options
There is no single diagnostic test for Alzheimer's disease, except for a brain biopsy (which is only performed if brain surgery is required) or an autopsy. Diagnosing Alzheimer's disease involves, in part, looking for and ruling out other conditions that can cause dementia, some of which are treatable and curable.
The diagnostic assessment includes interviewing the patient to determine their ability to perform daily tasks effectively. It also includes a thorough physical examination, a detailed neurological examination, and often blood tests. Various imaging techniques are used to visualize the brain, such as CT scans, MRI scans, and EEGs.
The tests often take more than one day (they are spread over several days to avoid exhausting the patient) and are usually performed on an outpatient basis. It is important that the assessment be conducted by a physician (usually a neurologist or geriatrician) experienced in diagnosing Alzheimer's disease. You can search for a qualified physician in the medical directory, at your local medical school, or at your local hospital. A mental status assessment is essential when diagnosing dementia. The doctor will ask the patient to perform mental exercises to assess their spatial awareness, memory, comprehension, language skills, and ability to perform simple calculations.
Treatment for Alzheimer's disease is multifaceted, ranging from lifestyle modifications to medications. Several drugs are available (tacrine and donepezil were among the first to be developed for this purpose). These medications increase the amount of the neurotransmitter acetylcholine and may temporarily improve thinking and memory.
Studies have found that estrogen (given during hormone replacement therapy), high doses of vitamin E, and the herbal remedy ginkgo may slow the progression of Alzheimer's disease. Medications can also address behavioral problems that are distressing for the patient and their family.
It is also important to encourage people with Alzheimer's to remain active, as this can help slow cognitive decline. This includes participating in mental and physical exercises.