top of page
  • Kim

What is Dementia?



  • Dementia refers to a clinical syndrome characterized by progressive cognitive decline that interferes with the ability to function independently.

  • Individuals suffering from dementia experience changes in cognition, function, and behaviors.

  • The clinical presentation of dementia varies greatly among individuals,

  • Cognitive impairment stems from injury to the cerebral cortex caused by synaptic failure, inflammation, and change in cerebral metabolism.

Symptoms

Some of the most common symptoms of dementia are:

  • agitation

  • apathy

  • aggression

  • psychosis

  • hallucinations

  • Delusions

Cognitive deficits may present as:

  • memory loss

  • communication and language impairments

  • agnosia (inability to recognize objects)

  • apraxia (inability to perform previously learned tasks)

  • impaired executive function (reasoning, judgement and planning)


Symptoms Vs. Pharmacotherapy

Symptoms that don’t respond well to pharmacotherapy,

behavioral and psychological symptoms such as:

  • wandering

  • hoarding

  • inappropriate behaviors (e.g., sexual disinhibition, eating inappropriate objects)

  • repetitive behaviors

  • restlessness

6 Cognitive Domains Affected by Dementia

  • Learning & memory

  • Language

  • Complex attention

  • Executive function

  • Perceptual-motor

  • Social cognition

  • Can be classified as mild or major, depending on the severity of symptoms


Mild Cognitive Impairment (MCI)

Patients with mild deficits who do not meet the criteria for dementia are considered to have mild cognitive impairment (MCI)

Experience difficulties with:

  • Memory

  • Language

  • Thinking

  • Judgement

  • Impairments are insufficient to interfere with daily life and independence

  • In early stages of Alzheimer’s disease individuals may present with MCI.

  • MCI patients are at higher risk of developing Alzheimer’s disease and other dementias than those without MCI

Subtypes of Dementia

Dementia is an umbrella term used to describe a clinical syndrome of progressive cognitive decline, but its subtypes are classified according to the cause of dementia.

The 4 common types of dementia—

  • Alzheimer's Disease

  • vascular dementia

  • Lewy body dementia

  • frontotemporal dementia


Alzheimer’s Disease

Most common, 60% to 80% of cases

  • Onset is usually undetectable, but short-term memory loss is usually the first sign

  • Caused by accumulation of beta-amyloid plaques and neurofibrillary tangles, first in entorhinal cortex and the hippocampus

  • Decrease in cholinergic neurotransmission causes loss of memory and cognition.

  • As it spreads to other parts of the brain, neurons progressively die in affected regions

  • Genetics is a contributing factor

  • Late-onset: after the age of 60

  • Early-onset: ages 30 to 60


Alzheimer’s Symptoms

Cognitive symptoms include:

  • Memory loss (poor recall, losing items)

  • Aphasia

  • Agnosia

  • Apraxia

  • Disorientation (impaired perception of time, unable to recognize familiar people)

  • Impaired visuospatial function and executive function


Noncognitive symptoms:

  • Depression

  • Psychotic symptoms (hallucinations, delusions)

  • Behavioral symptoms (such as physical and verbal aggression, motor hyperactivity, uncooperativeness, wandering, repetitive mannerisms and activities and combativeness).

Vascular Dementia

  • Second most prevalent form of dementia (20%)

  • Also called Multiinfarct Dementia

  • Sudden or gradual onset

  • Mixed dementia = co-existence of AD & vascular dementia

  • Correlated with:

o Cerebrovascular Disease:

o Stroke,

o Lacunar infarcts

o Atherosclerotic Comorbidities:

o Diabetes

o Hypertension

o Coronary heart disease

  • Results from neuronal deprivation of oxygen

  • Stroke is the most common cause

  • Symptoms vary by affected regions of the brain and the severity of the blood vessel damage.

  • Major stroke = confusion, disorientation, difficulty with speaking, understanding speech and vision loss

  • Memory may not be affected (mild memory impairment in early stage), but a sudden change in executive function (e.g., thinking, reasoning) after stroke can occur.


Lewy Body Dementia

  • Caused by abnormal deposits of alpha-synuclein protein (Lewy bodies) inside neurons

  • 5% to 15% of all dementias

  • Fluctuating cognitive impairment

  • Recurrent complex visual hallucinations

  • Memory loss tends to be observed in advanced LBD.

  • More than 80% of individuals with LBD develop parkinsonism


Other Symptoms:

  • Lethargy

  • Daytime somnolence

  • Sustained periods of staring into space

  • Periods of improved memory

  • Episodes of disorganized speech

  • Periods of decreased attention


Frontotemporal Dementia

  • Describes disorders that affect the frontal & temporal lobes , such as Pick’s disease

  • Occur at a younger age (40-75 years) than does AD.

  • Personality changes and behavioral disturbances are key features and occur early in the disease.

  • Visuospatial function is usually not affected

  • Behavioral disturbances: apathy, aggression, agitation

  • Less memory impairment in early stage


In Conclusion

  • Managing dementia is particularly challenging because of the complexity of the disorder

  • Treatment plan for each patient should be individualized to provide the most effective and safe therapy.

Resources:

Alzheimer's Disease



Kommentarer


bottom of page