About Dementia from the Alzheimer's Foundation of America

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Definition

* Dementia is a general term that describes a group of symptoms-such as loss of memory, judgment, language, complex motor skills, and other intellectual function-caused by the permanent damage or death of the brain's nerve cells, or neurons.

* One or more of several diseases, including Alzheimer's disease, can cause dementia.

* Alzheimer's disease is the most common cause of dementia in persons over the age of 65. It represents about 60 percent of all dementias.

* The other most common causes of dementia are vascular dementia, caused by stroke or blockage of blood supply, and dementia with Lewy bodies. Other types include alcohol dementia, caused by sustained use of alcohol; trauma dementia, caused by head injury; and a rare form of dementia, frontotemporal dementia.

* The clinical symptoms and the progression of dementia vary, depending on the type of disease causing it, and the location and number of damaged brain cells. Some types progress slowly over years, while others may result in sudden loss of intellectual function.

* Each type of dementia is characterized by different pathologic, or structural, changes in the brain, such as an accumulation of abnormal plaques and tangles in individuals with Alzheimer's disease, and abnormal tau protein in individuals with frontotemporal dementia.


Warning Signs

The symptoms of dementia vary, depending on the type of disease causing it. Some conditions that cause symptoms of dementia are reversible and others, like Alzheimer's disease, are irreversible.

If someone is exhibiting these symptoms, the person should check out his or her concerns with a healthcare professional. Awareness of these warning signs is not a substitute for a structured screening or consultation with a primary care provider.

Trouble with new memories
* Relying on memory helpers
* Trouble finding words
* Struggling to complete familiar actions
* Confusion about time, place or people
* Misplacing familiar objects
* Onset of new depression or irritability
* Making bad decisions
* Personality changes
* Loss of interest in important responsibilities
* Seeing or hearing things
* Expressing false beliefs


Diagnosis

>> Experienced clinicians can accurately diagnose dementia 90 percent of the time.

>> Accurate diagnosis is critical. Some conditions that cause symptoms of dementia, such as hormone imbalance, vitamin deficiency and infections, can be reversed. For irreversible dementias, treatment options vary depending on the disease.

>> Obtaining a proper diagnosis involves consulting with a healthcare professional expert in dementia, communicating symptoms and undergoing extensive testing.

>> Diagnostic tools include a complete medical history; blood, urine or other medical tests; neuropsychological tests that measure memory, problem solving, attention, and language; and brain scans.

>> Individuals with clinically diagnosed dementia have clear cognitive loss in two or more intellectual domains, such as amnesia (loss of memory) and aphasia (inability to communicate effectively), but almost all individuals with Alzheimer's disease demonstrate short-term memory impairment.

>> Other types of dementia may begin with a slow loss of memory function; however, a careful, clinical evaluation will usually provide information that suggests dementia other than Alzheimer's disease.


Symptoms

>> Symptoms of dementia are divided into two categories: cognitive, or intellectual, and psychiatric.

>> Differentiating them is important so that behavioral problems that are caused by loss of cognitive functioning are not treated with anti-psychotic or anti-anxiety medications.

>> The clinical symptoms of dementia vary, depending on the type of disease causing it, and the location and number of damaged brain cells. With Alzheimer's disease, manifestation of all of these symptoms is quite probable; with other types of dementia, it is possible to have some or all of these symptoms.

>> Cognitive, or intellectual, symptoms are amnesia, aphasia, apraxia and agnosia.

>> Amnesia is defined as loss of memory, or the inability to remember facts or events. We have two types of memories: the short-term (recent, new) and long-term (remote, old) memories. Short-term memory is programmed in a part of the brain called the temporal lobe, while long-term memory is stored throughout extensive nerve cell networks in the temporal and parietal lobes. In Alzheimer's disease, short-term memory storage is damaged first.

>> Aphasia is the inability to communicate effectively. The loss of ability to speak and write is called expressive aphasia. An individual may forget words he has learned, and will have increasing difficulty with communication. With receptive aphasia, an individual may be unable to understand spoken or written words or may read and not understand a word of what is read. Sometimes an individual pretends to understand and even nods in agreement; this is to cover-up aphasia. Although individuals may not understand words and grammar, they may still understand non-verbal behavior, i.e., smiling.

>> Apraxia is the inability to do pre-programmed motor tasks, or to perform activities of daily living such as brushing teeth and dressing. An individual may forget all motor skills learned during development. Sophisticated motor skills that require extensive learning, such as job-related skills, are the first functions impaired by dementia. More instinctive functions like chewing, swallowing and walking are lost in the last stages of the disease.

>> Agnosia is an individual's inability to correctly interpret signals from their five senses. Individuals with dementia may not recognize familiar people and objects. A common yet often unrecognized agnosia is the inability to appropriately perceive visceral, or internal, information such as a full bladder or chest pain.

>> Major psychiatric symptoms include personality changes, depression, and hallucinations and delusions.

>> Personality changes can become evident in the early stages of dementia. Signs include irritability, apathy, withdrawal and isolation.

>> Individuals with dementia may show symptoms of depression at any stage of the disease. Depression is treatable, even in the latter stages of dementia.

>> Psychotic symptoms include hallucinations and delusions, which usually occur in the middle stage of dementia. Hallucinations occur in about 25 percent of dementia cases and are typically auditory and/or visual. Sensory impairments, such as hearing loss or poor eyesight, tend to increase hallucinations in the elderly with dementia. Delusions affect about 40 percent of individuals with dementia.

>> Hallucinations and delusions can be very upsetting to the person with dementia. Common reactions are feelings of fear, anxiety and paranoia, as well as agitation, aggression and verbal outbursts.

>> Individuals with psychiatric symptoms tend to exhibit more behavioral problems than those without these symptoms. It is important to recognize these symptoms so that appropriate medications can be prescribed and safety precautions can be taken.

>> Psychotic symptoms can often be reduced through the carefully supervised use of medications. Talk to your primary care doctor, neurologist or geriatric psychiatrist about these symptoms because they are treatable.


Delirium

* Delirium is defined as a temporary confusion caused by underlying medical problems, drug toxicity or environmental factors.

* Delirium is a very common, yet often unrecognized condition in elderly individuals with dementia.

* It is marked by confusion and disorientation; fluctuating levels of consciousness; jerking motions; disruption of sleep-wake cycles; hallucinations, delusions and anxiety; memory impairment and altered speech; intermittent agitated behavior; mood changes; behavioral problems such as aggression and wandering; and changes in blood pressure and pulse.

* Delirium follows a time pattern. It has an abrupt onset—less than one month; and a short duration—not more than one month from the time the symptoms are detected to intervention and recovery.

* Medications are often the major cause of delirium in the elderly. This results from drug interactions, failure to take medication, slow absorption of medications, characteristics of the drug itself, or the use of anesthesia and other medication during and after surgery.

* Underlying medical problems that may cause delirium are bladder infection, pneumonia, dehydration, metabolic disorders, oxygen deficiency, constipation, and urinary retention.

* Environmental factors may also contribute to delirium. This ranges from sensory overload, such as too much noise, to sensory deprivation stemming from isolation, hearing impairment and lack of environmental stimulation.

* It is important to identify the risk factors for delirium and learn about preventative measures. For example, providing adequate hydration and carefully managing medication are preventative approaches.

* Delirium does not involve structural brain damage.

* Individuals may completely improve from delirium if the medical problem is identified and treated.

* If delirium is left untreated, individuals develop additional complications that may result in poor outcome or death.


Depression

* Individuals diagnosed with dementia can present with coexisting depression.

* Several symptoms are common to both dementia and depression: apathy, lack of interest in people or activities, poor sleep, restlessness, memory loss, and difficulty concentrating.

* Distinguishing between dementia and depression, and determining whether each condition exists or if they co-exist is critical to ensure proper treatment.

* The frequency and severity of depression remain fairly constant through most stages of Alzheimer's disease.

* For most individuals with Alzheimer's disease who develop depression, it tends to be mild and moderate in severity, and suicidal behavior or completed suicide is rare.

* Depression may cause or worsen memory loss and other cognitive impairment.

* It appears that Alzheimer's disease is more likely to develop in people who have depression plus cognitive impairment, but that depression occurring without cognitive impairment does not increase the risk of developing the disease.

* Counseling or psychotherapy may be helpful in mild to moderate depression in the earliest stages of dementia, but systematic studies on this issue are lacking.

* Antidepressants are usually indicated for those with Alzheimer's disease who demonstrate persistent or severe depression. However, only half of the published research shows superiority for antidepressant medication over placebo in the treatment of depression in those with Alzheimer's disease or dementia in general.

* If a physician prescribes antidepressant medications, it is important to monitor the choice of medication, dosage, possible side effects, impact on cognition and activities of daily living, and the status of the depression.

Contributed by D.P. Devanand, M.D., a professor of clinical psychiatry and neurology at the College of Physicians and Surgeons at Columbia University in New York.