You may often hear the statement, “My loved one has dementia, not Alzheimer’s disease”. It is often followed by the question, “So what’s the difference?”
Dementia is not a disease or illness. Dementia is a word that describes a decline in cognitive abilities — such as thinking, memory, judgment and reasoning, language, understanding of place and time, and social abilities — severe enough to disrupt daily life.
Dementia is a word that describes a group of symptoms caused by a disease, illness, or other condition. It is a broad-category word, like the word cancer.
Just as there are different types of cancer, there are different types of dementia.
Many causes of dementia are treatable, and with treatment, symptoms are improved or reversed. Common conditions that cause reversible dementia are medication misuse, medication interaction, depression, poor nutrition, severe dehydration, thyroid problems, infection, high fever, and stroke.
Other causes of dementia are irreversible, progressive, and degenerative, meaning that symptoms will not improve with treatment, symptoms will get worse over time, and the disease attacks and damages brain cells, causing a loss of brain functioning that will eventually cause death.
Alzheimer’s disease is the most common type of irreversible dementia in adults ages 65 and older. According to the Alzheimer’s Association, Alzheimer’s disease accounts for between 60 percent and 80 percent of all cases of dementia.
We don’t know if plaques and tangles in the brain are the result of Alzheimer’s disease, or if they cause Alzheimer’s disease.
However, we do know that the buildup of plaques and tangles cause brain cells to die, which causes the brain to shrink.
Plaques are an abnormal buildup of protein between brain cells, and tangles are abnormal strings of protein within brain cells.
The second most common type of dementia is vascular dementia. Conditions that lead to vascular dementia include stroke, diabetes and hypertension.
Sometimes dementia symptoms are caused by more than one type of dementia. The most common combination of dementias is Alzheimer’s disease and vascular dementia. Other types of dementia include Dementia with Lewy bodies, Parkinson’s disease, Huntington’s disease, and others.
Although we do not know what causes Alzheimer’s disease, the No. 1 risk factor for developing Alzheimer’s disease is age. After the age of 65, the risk of developing Alzheimer’s disease doubles approximately every five years.
The second most important risk factor for developing Alzheimer’s is family history. Individuals who have a parent, brother, sister, or child with Alzheimer’s disease are more likely to develop the disease.
The familial risk increases if more than one family member has Alzheimer’s disease.
A rare form of Alzheimer’s disease that affects individuals in their 40s and 50s, and less commonly in their late 30s, is called early-onset Alzheimer’s disease, sometimes called younger-onset Alzheimer’s disease.
Approximately 5 percent of the more than 5 million Americans with Alzheimer’s disease have early-onset. Early-onset Alzheimer’s disease tends to run in families, and research has discovered that the most common risk factor for developing early-onset Alzheimer’s is genetics.
Other risk factors that may play a role in developing Alzheimer’s are:
Gender. Women are slightly more likely to develop Alzheimer’s disease than men, even if we discount the fact that women live longer than men.
Mild Cognitive Impairment. People who have mild memory problems and other symptoms not severe enough to be diagnosed as dementia have an increased risk, but not a certainty, of developing Alzheimer’s.
Head Injury. People who have had a severe head injury or repeated head trauma appear to have a greater risk of Alzheimer’s disease.
Lifestyle and heart health. Although there is no proof that lifestyle can reduce your risk of developing Alzheimer’s, some evidence suggests that the same factors that increase the risk of heart disease may also increase the risk of developing Alzheimer’s.
Alzheimer’s disease typically develops slowly and gradually gets worse over the course of several years. It eventually affects most areas of the brain, and the rate of progression and order of symptoms is not the same for every person who develops Alzheimer’s.
While primary care physicians can usually determine if a person has dementia, determining the exact cause of dementia is more difficult.
Your physician will probably refer you to one or more specialists who are board certified in areas of expertise involved in the diagnosis and care of Alzheimer’s disease.
-Neurologists specialize in diseases of the brain and nervous system.
-Psychiatrists specialize in the diagnosis and treatment of mental disorders.
-Neuropsychologists are psychologists with special training in testing memory and other areas of brain functioning.
-Geriatricians specialize in treating older adults, recognizing the difference between disease and the effects of normal aging.
There is no single test that can diagnose Alzheimer’s disease — yet. The diagnosis of Alzheimer’s disease is an exclusionary diagnosis, meaning that experts “rule out” or “exclude” many other causes of the presenting dementia symptoms.
Currently the only way to get an absolute diagnosis of Alzheimer’s disease is by examining brain tissue from a biopsy or an autopsy. However, when specialists use nationally developed diagnostic criteria, diagnosis is considered about 90 percent accurate.
The process for diagnosing Alzheimer’s disease does not always include a brain scan. However, it usually includes a thorough medical history, the Mini-Mental State Exam and psychiatric history, a thorough medical exam that includes a physical exam, lab tests, and an X-ray, and neuropsychological testing.
For more information about caring for those with Alzheimer’s disease and dementia, contact Spring Arbor.