This section examines dementia as it relates to cognitive impairment, differentiates dementia from other conditions, looks at dementia screening, and discusses types of dementia. Finally, it addresses the care of those who have dementia.
Dementia and Cognitive Impairment
Dementia is a descriptive term for a collection of symptoms that can be caused by a number of disorders that affect the brain. It is estimated that as many as 6.8 million people in the United States have dementia, and at least 1.8 million of those are severely affected. Studies in some communities have found that almost half of all people age 85 and older have some form of dementia. Although it is common in very elderly individuals, dementia is not a normal part of the aging process. Many people live into their 90s and even 100s without any symptoms of dementia (NINDS, 2013).
People with dementia have significantly impaired mental functioning that interferes with normal activities and relationships. They can lose their ability to solve problems and maintain emotional control, and may experience personality changes and behavioral problems such as agitation, delusions, and hallucinations.
Memory loss is a common symptom of dementia but by itself does not mean a person has dementia. Dementia is diagnosed only if two or more brain functions—such as memory, language, perception, reasoning, or judgment, among others—are significantly impaired.
Although memory and other cognitive functions change with age, age-related cognitive change is not dementia. Memory may not be as sharp and there may be word-finding difficulties—it may take longer to do certain mental tasks such as memorizing a string of words or numbers. Multi-tasking may be a thing of the past. Older adults with age-related cognitive changes can however read, operate a computer, manage their finances, and prepare their own meals—they do not forget what a coffee pot is or how to operate a microwave. They understand when they are in danger and know that they should call for help or get out of a house if there is a fire.
Mild cognitive impairment (MCI) is a condition in which people have memory problems that are noticeably worse than age-related changes. However, people with MCI do not have the problems associated with dementia such as personality and cognitive changes. Some people with MCI do go on to develop Alzheimer’s Disease (AD), but not everyone does.
Differentiating Dementia from Other Conditions
[Much of the material in this section is taken from NINDS, 2013.]
The symptoms of a number of medical conditions mimic those of dementia and this must be considered when evaluating a person experiencing cognitive changes. Gerontology specialists speak of the “Three Ds”—dementia, delirium, and depression—because these are the most prevalent reasons for cognitive impairment in older adults. Delirium and depression can cause cognitive changes that may be mistaken for dementia, and healthcare providers and caregivers should learn to distinguish among the three conditions.
Delirium is a sudden, severe confusion with rapid changes in brain function. Delirium develops over hours or days and is temporary and reversible. It can occur after general anesthesia, from infections (eg, UTI, pneumonia), from fluid/electrolyte or acid/base disturbances, or from other conditions that deprive the brain of oxygen. Pain can also contribute to delirium, as can the medications used to treat pain. Being in an unfamiliar environment such as adult daycare or a nursing home can also contribute to delirium.
Depression is caused by neurochemical imbalances in the brain. It can lead to cognitive impairment, which should improve when the depression is treated. People with depression are aware of the date and time; however, they may answer “I don’t know” to orientation questions and may not make eye contact. They may have a flat affect (show little expression) and may speak in a monotone. A smile does not rule out the presence of depression; people who are depressed may smile while describing the hopelessness of life. Irritability or verbal expression of pessimism, sadness, or hopelessness may indicate depression. Depression commonly occurs in the early stages of Alzheimer’s disease (AD) as individuals become aware of their loss of cognitive function.
There are other conditions that can cause dementia-like symptoms; many of these conditions are reversible with appropriate treatment (NINDS, 2013):
- Reactions to medications or interactions between medications
- Metabolic problems and endocrine abnormalities
- Thyroid abnormalities
- Too little or too much sodium or calcium
- Pernicious anemia
- Nutritional deficiencies
- Thiamine deficiency (vitamin B1)—can occur with chronic alcoholism and can seriously impair mental abilities, in particular memories of recent events
- Dehydration—can cause mental impairment that resembles dementia
- Infections—can cause neurologic symptoms, including confusion or delirium due to fever or other side effects of the body’s fight to overcome the infection
- Subdural hematomas
- Poisoning—exposure to lead, heavy metals, or other poisonous substances Symptoms may or may not resolve after treatment, depending on how badly the brain is damaged.
- Abuse of alcohol, prescription medications, and recreational drugs
- Brain tumors
- Anoxia—a diminished supply of oxygen to the brain. Recovery depends on the severity of the oxygen deprivation.
- Heart and lung problems—chronic lung disease or heart problems that prevent the brain from receiving adequate oxygen can starve brain cells and lead to the symptoms of dementia
[This section is taken largely from NINDS, 2013.]
For people with AD or other progressive dementias, early diagnosis allows them to plan for the future while they are still able to make decisions. There are a number of strategies for the assessment and diagnosis of dementia. Screening begins with a detailed patient history to determine when the symptoms began and to determine the person’s overall medical condition.
The physical examination helps to rule out treatable causes of dementia and identify signs of stroke or other disorders that can contribute to dementia. Look for signs of illness, such as heart disease or kidney failure, that can overlap with dementia. A review of medications is necessary to determine whether any medications or medication interactions are causing or contributing to the symptoms of dementia.
The neurologic examination assesses balance, motor control, sensory functions, and reflexes, and looks for the presence of any neurologic condition (eg, movement disorders, stroke) that may affect the patient’s diagnosis or is treatable with drugs.
Cognitive tests measure memory, language skills, math skills, and other abilities related to mental functioning. The Mini-Mental State Examination (MMSE) may be used to examine orientation, memory, and attention, the ability to name objects, follow verbal and written commands, write a sentence spontaneously, and copy a complex shape.
Brain scans are used to identify strokes, tumors, or other problems that can cause dementia. Cortical atrophy—degeneration of the brain’s cortex—is common in many forms of dementia and may be visible on a brain scan. Brain scans also can identify changes in the brain’s structure and function that suggest AD.
Electroencephalograms (EEGs) may be used in people with suspected dementia. Many patients with moderately severe to severe AD have abnormal EEGs. An EEG may also be used to detect seizures, which occur in about 10% of AD patients as well as in many other disorders.
A variety of laboratory tests are available to diagnose dementia or rule out other conditions, such as kidney failure, that can contribute to symptoms. A partial list of these tests includes a complete blood count, blood glucose test, urinalysis, drug and alcohol tests (toxicology screen), cerebrospinal fluid analysis (to rule out specific infections that can affect the brain), and analysis of thyroid and thyroid-stimulating hormone levels.
A psychiatric evaluation may be obtained to determine if depression or another psychiatric disorder may be causing or contributing to a person’s symptoms.
Common Types of Dementia
Early, characteristic symptoms
Proportion of dementia cases
*Alzheimer’s disease (AD)
Dementia with Lewy
Cortical Lewy bodies
Types of Dementia
[This section is taken largely from NINDS, 2013.]
Various disorders and factors contribute to the development of dementia. Neurodegenerative disorders such as AD, frontotemporal disorders, and Lewy body dementia result in a progressive and irreversible loss of neurons and brain functions. Currently, there are no cures for these progressive neurodegenerative disorders. However, other types of dementia can be halted or even reversed with treatment.
In some dementias, a protein called tau clumps together inside nerve cells in the brain, causing the cells to stop functioning properly and die. Disorders that are associated with an accumulation of tau are called tauopathies, and they include Alzheimer’s disease, Corticobasal degeneration (CBD), Frontotemporal disorders (FTD).
In these brain disorders, a protein called alpha-synuclein accumulates inside neurons. Although it is not fully understood what role this protein plays, changes in the protein and/or its function have been linked to Parkinson’s disease and other disorders.
One type of synucleinopathy, Lewy body dementia, involves protein aggregates called Lewy bodies, balloon-like structures that form inside of nerve cells. The initial symptoms may vary, but over time, people with these disorders develop very similar cognitive, behavioral, physical, and sleep-related symptoms. Lewy body dementia is one of the most common causes of dementia, after Alzheimer’s disease and vascular disease.
Vascular Dementia and Vascular Cognitive Impairment
Vascular dementia and vascular cognitive impairment (VCI) are caused by injuries to the vessels supplying blood to the brain. These disorders can be caused by brain damage from multiple strokes or any injury to the small vessels carrying blood to the brain.
Dementia risk can be significant even when individuals have suffered only small strokes. Vascular dementia and VCI arise as a result of risk factors that similarly increase the risk for cerebrovascular disease (stroke), including atrial fibrillation, hypertension, diabetes, and high cholesterol.
Autopsy studies looking at the brains of people who had dementia suggest that a majority of those age 80 and older probably had “mixed dementia,” caused by both AD-related neurodegenerative processes and vascular disease-related processes. In fact, some studies indicate that mixed vascular-degenerative dementia is the most common cause of dementia in the elderly.
In a person with mixed dementia, it may not be clear exactly how many of a person’s symptoms are due to AD or another type of dementia. In one study, approximately 40 percent of people who were thought to have AD were found after autopsy to also have some form of cerebrovascular disease. Several studies have found that many of the major risk factors for vascular disease also may be risk factors for AD.
Researchers are still working to understand how underlying disease processes in mixed dementia influence each other. It is not clear, for example, if symptoms are likely to be worse when a person has brain changes reflecting multiple types of dementia. Nor do we know if a person with multiple dementias can benefit from treating one type, for example, when a person with AD controls high blood pressure and other vascular disease risk factors.
The most common type of dementia in those over age 65, Alzheimer’s disease (AD), is caused by the formation of abnormal proteins within the brain called plaques and tangles. Damage typically begins in an area of the cerebrum called the hippocampus, which is responsible for the formation of new memories. In fairly rapid succession, plaques and tangles spread forward to the temporal and frontal lobes, affecting language, judgment, learning, comprehension, orientation, and emotions. Although almost everyone with AD is elderly, it is not considered to be a normal part of aging.
In most people, symptoms of AD appear after age 60. However, there are some early-onset forms of the disease that are usually linked to a specific gene defect, which may appear as early as age 30. AD causes a gradual decline in cognitive abilities, usually during a span of 7 to 10 years. Nearly all brain functions, including memory, movement, language, judgment, behavior, and abstract thinking, are eventually affected. Tangles are largely made up of a protein called tau which is part of a healthy nerve cell’s structural support and which is also responsible for delivering substances throughout the cell. In AD, tau is changed in a way that makes it collect into tangles, which causes the collapse of the neuron’s support and transport system.
Today, 5.4 million Americans have Alzheimer’s disease and about 3.3 million of them are women. By 2050, up to 16 million people will have AD. In 2016 the direct costs of caring for those with AD was estimated to be $236 billion, with Medicare paying nearly half of that (Alzheimer’s Association, 2016, 2016a).
In Texas in 2016, 350,000 people were living with Alzheimer’s, which is the sixth leading cause of death in the state. Of those 350,000, 57,000 were age 65-74, 160,000 were age 75-84, and 140,000 were 85 and older. In 2015, 1.4 million Texans acted as caregivers for those with Alzheimer’s and other dementias (Alzheimer’s Association, 2016b).
The Texas Department of State Health Services operates the state’s Alzheimer’s Disease Program, which was mandated by the legislature in 1987 to provide information and support to Alzheimer’s patients, their families, and their long-term care providers. Information can be obtained from the program’s website at http://www.dshs.texas.gov/alzheimers/ (TX DSHS, 2019).
Care of Those with Dementia
Those with moderate or advanced dementia often need round-the-clock care and supervision and also may need assistance with daily activities such as eating, bathing, and dressing. Meeting these needs takes patience, understanding, and careful thought by the person’s caregivers.
Communicating with a person with dementia is a learned skill. Important elements include:
- Setting a positive mood
- Getting the person’s attention
- Stating your message clearly
- Asking simple answerable questions
- Listening with ears, eyes, and heart
- Breaking activities into steps
- Using distracting and redirection to deal with upset and agitation
- Responding with affection and reassurance
- Remembering the past as a soothing technique
- Maintaining a sense of humor
Caregiving is a challenging task made even more so when caring for someone with dementia. Print, online, and in-person resources can help caregivers:
- modify the environment to make it safer and help keep the person with dementia from wandering
- understand frustrating behaviors and how to work with the person
- deal with personal issues of cleanliness—toileting, bathing, and dressing
- manage diet and nutrition
- provide activities and exercise
- deal with agitation, paranoia, and other difficult behaviors
Critical but often overlooked by family caregivers is the need for a caregiver to care for themselves (FCA, 2016).Back Next