Dementia: general information

Dementia is a chronic, widespread, and usually irreversible decline in cognitive function.

The diagnosis of dementia is clinical; laboratory and neuroimaging studies are used for differential diagnosis and to identify treatable diseases. Treatment of dementia is supportive. In some cases, cholinesterase inhibitors temporarily improve cognitive function.

Dementia can develop at any age, but it mainly affects older people (about 5% of them are aged 65-74 years and 40% - over 85 years). More than half of these patients need outside medical care. At least 4-5 million people in the United States have dementia.

According to the most common definition that can be used in practice, dementia is a disorder of memory and at least one other cognitive function. Cognitive functions include: perception (gnosis), attention, memory, counting, speech, thinking. Dementia can only be discussed when these disorders of cognitive functions lead to noticeable difficulties in everyday life and professional activities.

According to DSM-IV, dementia is diagnosed when memory impairment results in functional deficit and is associated with at least two of the following disorders: aphasia, apraxia, agnosia, and impairment of higher executive functions. The presence of delirium excludes the diagnosis of dementia (American Psychiatric Association, 1994).

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Causes of dementia

Dementia can be classified in several ways: Alzheimer's and non-Alzheimer's dementia, cortical and subcortical, irreversible and potentially reversible, widespread and selective. Dementia can be a primary neurodegenerative disorder or occur as a consequence of other conditions.

The most common are Alzheimer's disease, vascular dementia, dementia with Lewy bodies, frontotemporal dementia, and HIV-associated dementia. Other conditions associated with dementia include Parkinson's disease, Huntington's chorea, progressive supranuclear palsy, Creutzfeldt-Jakob disease, Gerretmann-Sträussler-Scheinker syndrome, other prion diseases, and neurosyphilis. Determining the cause of dementia is difficult; definitive diagnosis often requires postmortem examination of the brain. Patients may have more than 1 type of dementia (mixed dementia).

Classification of dementia

Classification	Examples
Primary neurodegenerative (cortical)	Alzheimer's disease Frontotemporal dementias Mixed dementias with an Alzheimer's component
Vascular	Lacunar disease (eg, Binswanger's disease) Multi-infarct dementia
Associated with Lewy bodies	Diffuse Lewy Body Disease Parkinsonism combined with dementia Progressive supranuclear palsy Corticobasal ganglionic degeneration
Associated with intoxication	Dementia associated with chronic alcohol use Dementia associated with long-term exposure to heavy metals or other toxins
Associated with infections	Dementia associated with fungal infection (eg, cryptococcal) Dementia associated with spirochetal infection (eg, syphilis, Lyme borreliosis) Dementia associated with viral infection (eg, HIV, postencephalitic)
Associated with prion contamination	Creutzfeldt-Jakob disease
Associated with structural damage to the brain	Brain tumors Normal pressure hydrocephalus Subdural hematoma (chronic)

Some organic brain diseases (such as normal-pressure hydrocephalus, chronic subdural hematoma), metabolic disorders (including hypothyroidism, vitamin B ₁₂ deficiency ), and intoxications (eg, lead) can cause a slow loss of cognitive function that improves with therapy. These conditions are sometimes called reversible dementia, but some experts restrict the term dementia to situations of irreversible loss of cognitive function. Depression can mimic dementia (and has been formally called pseudodementia); the two conditions often coexist. Changes in cognitive function inevitably occur with age, but they are not considered dementia.

Any disease can aggravate cognitive deficits in patients with dementia. Delirium often develops in patients with dementia. Medicines, especially benzodiazepines and anticholinergics (in particular, some tricyclic antidepressants, antihistamines and antipsychotics, benztropine), can temporarily worsen symptoms of dementia, as can alcohol, even in moderate doses. New or progressive renal or hepatic insufficiency can reduce drug clearance and lead to the development of drug intoxication after many years of using drugs in standard dosages (for example, propranolol).

Causes of dementia

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Symptoms of dementia

In dementia, all cognitive functions are totally impaired. Often, short-term memory loss may be the only symptom. Although symptoms occur over a specific time interval, they may be divided into early, intermediate, and late. Personality and behavioral changes may develop early or late. Motor and other focal neurological deficit syndromes occur at different stages of the disease, depending on the type of dementia; they develop earliest in vascular dementia and later in Alzheimer's disease. The frequency of seizures increases somewhat at all stages of the disease. Psychoses—hallucinations, mania, or paranoia—occur in approximately 10% of patients with dementia, although in a significant percentage of patients the onset of these symptoms is temporary.

Early symptoms of dementia

Early onset of memory loss; learning and retaining new information becomes difficult. Language problems (especially word choice), mood swings, and development of personality changes. Patients may have progressive problems with daily activities (checkbook manipulation, finding directions, forgetting the location of things). Abstract thinking, insight, and judgment may be impaired. Patients may respond to loss of independence and memory with irritability, hostility, and agitation.

Agnosia (loss of the ability to identify objects while sensory functions are preserved), apraxia (loss of the ability to perform a previously planned and known motor act despite the preservation of motor function), or aphasia (loss of the ability to understand or produce speech) may subsequently limit the patient's functional abilities.

Although early symptoms of dementia may not reduce sociability, family members report unusual behavior associated with emotional lability.

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Intermediate symptoms of dementia

Patients become unable to learn and absorb new information. Memory for remote events is reduced, but not completely lost. Patients may need assistance in maintaining daily life activities (including bathing, eating, dressing, and physical needs). Personality changes increase. Patients become irritable, aggressive, self-centered, unyielding, and very easily embittered, or they become passive with monotonous reactions, depressed, unable to make final judgments, lacking initiative, and seeking to withdraw from social activity. Behavioral disturbances may develop: patients may become lost or suddenly inappropriately excited, hostile, uncommunicative, or physically aggressive.

In this stage of the disease, patients lose their sense of time and space because they are unable to effectively use their normal environment and social cues. Patients often become lost and are unable to find their bedroom and bathroom on their own. They remain ambulatory, but with an increased risk of falls and injuries due to disorientation. Changes in perception or understanding may accumulate and transform into psychosis with hallucinations and paranoia and mania. The rhythm of sleep and wakefulness is often disorganized.

Late (severe) symptoms of dementia

Patients are unable to walk, feed themselves, or perform any other daily activities, and they become incontinent. Short-term and long-term memory are completely lost. Patients may lose the ability to swallow. They are at risk for malnutrition, pneumonia (especially from aspiration), and pressure ulcers. Because they become completely dependent on others for care, long-term care becomes absolutely necessary. Mutism eventually develops.

Since such patients are unable to report any symptoms to the physician, and since elderly patients often do not develop fever and leukocytosis in response to infection, the physician must rely on his own experience and insight when the patient develops signs of somatic disease. In the final stages, coma develops, and death usually occurs from an accompanying infection.

Symptoms of dementia

Diagnosis of dementia

Diagnosis focuses on distinguishing delirium from dementia and identifying the areas of the brain that have been damaged and assessing the likely reversibility of the underlying cause. Distinguishing dementia from delirium is critical (since delirium symptoms are usually reversible with prompt treatment) but can be difficult. Attention should be assessed first. If the patient is inattentive, delirium is likely, although progressive dementia may also be associated with marked loss of attention. Other features that differentiate delirium from dementia (e.g., duration of cognitive impairment) are clarified by history taking, physical examination, and assessment of specific causes of the disorder.

Dementia should also be distinguished from age-related memory problems; older people have memory impairments (in the form of retrieval of information) compared to younger people. These changes are not progressive and do not significantly affect daily activities. If such people have enough time to learn new information, their intellectual performance remains good. Moderate cognitive impairment is represented by subjective complaints about memory; memory is weakened compared to the age reference group, but other cognitive areas and daily activities are not impaired. More than 50% of patients with moderate cognitive impairment develop dementia within 3 years.

Dementia must also be distinguished from cognitive impairment associated with depression; these cognitive impairments resolve with treatment of depression. Older depressed patients show signs of cognitive decline, but unlike patients with dementia, they tend to exaggerate (emphasize) memory loss and rarely forget important current events or personal landmarks.

Neurological examination reveals signs of psychomotor slowness. During the examination, patients with depression make little effort to respond, while patients with dementia often make significant efforts but respond incorrectly. When depression and dementia coexist in a patient, treatment for depression does not promote full recovery of cognitive functions.

The best test for detecting dementia is an assessment of short-term memory (e.g. remembering 3 objects and being able to name them after 5 minutes); patients with dementia forget simple information after 3-5 minutes. Another assessment test can be an assessment of the ability to name objects of different categorical groups (e.g. a list of animals, plants, pieces of furniture). Patients with dementia have difficulty naming even a small number of objects, while those without dementia can easily name a larger number.

In addition to short-term memory loss, a diagnosis of dementia requires the presence of at least the following cognitive impairments: aphasia, apraxia, agnosia, or loss of the ability to plan, organize, follow a sequence of actions, or think abstractly (impairments of "executive" or regulatory functions). Each type of cognitive deficit can have a significant impact on functional loss and represent a significant loss of a preexisting level of functioning. In addition, cognitive impairment may only become apparent in the setting of delirium.

History taking and physical examination should focus on signs of systemic diseases that may indicate a possible cause of delirium or on treatable diseases that can cause cognitive impairment (vitamin B12 deficiency, advanced syphilis, hypothyroidism, depression).

A formal mental status examination should be performed. In the absence of delirium, a score of less than 24 confirms dementia; adjustment for educational level improves diagnostic accuracy. If the diagnosis of dementia is beyond doubt, patients should undergo full neuropsychological testing to identify specific deficit syndromes associated with dementia.

The examination should include CBC, liver function tests, thyroid hormone levels, and vitamin B12 levels. If clinical examination confirms specific abnormalities, other tests (including HIV and syphilis testing) are indicated. Lumbar puncture is rarely performed but may be indicated in the presence of chronic infection or if neurosyphilis is suspected. Other tests may be used to rule out causes of delirium.

CT or MRI should be obtained early in the evaluation of a patient with dementia or after a sudden change in cognitive or mental status. Neuroimaging may reveal reversible structural changes (eg, normal-pressure hydrocephalus, brain tumors, subdural hematoma) and metabolic abnormalities (eg, Hallewarden-Spatz disease, Wilson disease). EEG is sometimes helpful (eg, in cases of recurrent falls and eccentric, bizarre behavior). Functional MRI or single-photon emission CT may provide information about cerebral perfusion and aid in differential diagnosis.

Diagnosis of dementia

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Prognosis and treatment of dementia

Dementia usually progresses. However, the rate (speed) of progression varies widely and depends on a number of causes. Dementia shortens life expectancy, but survival estimates vary.

Safety measures and appropriate environmental conditions are extremely important in treatment, as is caregiver support. Certain medications may be helpful.

Patient safety

Occupational therapy and physical therapy determine the patient's safety at home; the aim of these activities is to prevent accidents (especially falls), manage behavioral problems, and plan corrective measures in case of dementia progression.

The extent to which the patient can function in different settings (in the kitchen, in the car) should be assessed. If the patient is unable to perform these activities and remains in the same environment, some protective measures may be necessary (including not turning on the gas/electric stove, restricting access to the car, confiscating the keys). Some situations may require the doctor to inform the traffic management department about the patient with dementia, since in certain conditions such patients can no longer continue to drive a car. If the patient develops a tendency to leave the house and wander, a monitoring alarm system should be installed. Ultimately, assistance (housekeepers, home health care services) or a change in the environment (ensuring daily activities without stairs and steps, assistive devices, help from professional nurses) may be required.

Environmental modification activities

Providing appropriate environmental conditions for a person with dementia can help to build a sense of self-care and self-confidence. Such interventions include orientation training; bright lighting, a light, familiar environment, minimizing new stimulation, and regular, low-stress activities.

A large calendar and clock should be a routine part of daily activities and help with orientation; medical staff should wear a large name badge and repeatedly introduce themselves to the patient. Changes in the patient's environment and routines should be explained to the patient in a simple and thorough manner, while avoiding emergency procedures. Patients need time to comprehend and become familiar with the changes that have occurred. Explaining to the patient the sequence of his or her actions (e.g., going to the bathroom or eating) is necessary to prevent resistance or inappropriate reactions. Often, visits from medical staff and familiar people keep patients socially adapted.

The room should be adequately lit and contain sensory stimuli (including radio, television, night lights) to help the patient remain oriented and concentrate. Silence, darkness, and placing the patient in isolated rooms should be avoided.

Activity helps patients function better, and those who had certain interests before the onset of dementia have a more favorable prognosis. Activity should be enjoyable, supported by some stimulation, but not involve too many choices (alternatives) and complex tasks. Physical exercise helps reduce excessive motor activity, loss of balance, and maintains the necessary tone of the cardiovascular system, so it should be done daily. Exercise can also help improve sleep and reduce behavioral disturbances. Occupational therapy and music therapy help maintain fine motor control and support nonverbal stimulation. Group therapy (including reminiscence therapy, socialization of activity) can help maintain conversational and interpersonal experience.

Anti-dementia drugs

Exclusion from use or limitation of dosages of drugs that affect the central nervous system often improves the patient's functional status. Sedatives and anticholinergics, which tend to worsen the course of dementia, should be excluded.

Cholinesterase inhibitors such as donepezil, rivastigmine, and galantamine are somewhat effective in improving cognitive function in patients with Alzheimer's disease or dementia with Lewy bodies and may be useful in other forms of dementia. These drugs increase acetylcholinesterase levels in the brain by inhibiting acetylcholinesterase. Newer drugs such as memantine may help slow the progression of moderate to severe dementia and can be used with cholinesterase inhibitors.

Other medications (including antipsychotics) are used to control behavioral disturbances. Patients with dementia and signs of depression should be treated with drugs from the group of non-anticholinergic antidepressants, preferably from the group of selective serotonin reuptake inhibitors.

Help from a caregiver

Immediate family members bear a great deal of responsibility for the care of a person with dementia. Nurses and social workers can train them and other caregivers to better meet the needs of the patient (including how to share daily care and manage finances), and training should be ongoing. Other resources (including support groups, educational materials, the Internet) should be available. Caregivers may experience situational stress. Stress may be caused by concerns about protecting the patient and feelings of frustration, exhaustion, anger, and resentment at having to care for someone in this way. Caregivers should be aware of early signs of stress and depression in caregivers and, if necessary, support caregivers (including social workers, nutritionists, nurses, home care specialists). If unusual injuries occur in patients with dementia, an assessment for possible abuse of the elderly patient is necessary.

End of life

Because judgment and thinking steadily decline in patients with dementia, it may be necessary to appoint a family member, guardian, or attorney to manage financial affairs. In the early stages of dementia, before the patient becomes incapacitated, the patient's wishes regarding guardianship should be clarified and the financial and legal affairs (including the reliability of the attorney and the reliability of the medical attorney) should be put in order. Once these documents are signed, the patient's capacity should be assessed and the results of this assessment recorded.

Treatment of dementia

Dementia and Forensic Psychiatry

Dementia is defined in ICD-10 as a syndrome caused by disease of the brain, which is usually chronic or progressive. It is characterized by deficits in a range of higher cortical functions, including memory, thinking, orientation, comprehension, arithmetic, learning, language, and judgment. All this occurs in the presence of clear consciousness. Often there is a concomitant decline in social behavior and emotional control. The decline in cognitive abilities usually results in significant problems in daily living, particularly with washing, dressing, eating, personal hygiene, and toileting. The classification of types of this disorder is based on the underlying disease processes. The two main types are Alzheimer's disease and cerebrovascular disease. Others include Pick's disease, Creutzfeldt-Jakob disease, Huntington's disease, Parkinson's disease, and HIV-related disease. Lishman defines dementia as "an acquired global impairment of intellect, memory, and personality, but without impairment of consciousness." Unlike delirium or intoxication, in dementia consciousness must not be clouded. There must be evidence of a specific organic factor etiologically associated with the disorder, or such an organic factor can be suspected.

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Dementia and law

The effects of dementia may include increased irritability, increased aggressiveness or suspiciousness (which may lead to violence), disinhibition (which may lead to offences such as unwanted sexual behaviour) or forgetfulness (which may result in offences such as absent-minded shoplifting). Dementia falls squarely within the definition of mental illness in the Mental Health Act 1983. Dementia may therefore form the basis for treatment recommendations under certain sections of the Mental Health Act. The court will be concerned with the degree of dementia and how it affects the offender's judgment and behaviour. The severity of the illness is relevant in determining the extent of mitigating circumstances or liability.

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