Dementia biology and behavior

mild cognitive impairment

• cognitive changes are of concern to individual and or family

• one or more cognitive domains impaired significantly

• preserved activities of daily living

• decline greater than expected for their age and education

• memory loss predominates

• can progress to dementia or revert to normal or stay the same

• tests results discriminate between healthy aging, patients with MCI, and mild dementia groups

• prevalence: 15-20% of 65+ year olds

what would a physician look at to rule out another cause of the decline

• R/O vascular, traumatic, medical causes of cognitive decline, where possible

• provide evidence of longitudinal decline in cognition, when feasible

• report history consistent with AD genetic factors, where relevant

dementia

• noticeable memory, thinking, and behavioral symptoms that impair a person’s ability to function in daily life

  • ability to generate coherent speech and understand spoken or written language

  • ability to recognize or identify objects

  • ability to execute motor activities

  • ability to think abstractly, make sounds judgements, and plan and carry out complex tasks (executive function)

• cognitive decline must be severe enough to interfere with daily life

common symptoms of dementia

• memory loss that disrupts daily life

• challenges in planning or solving problems

• difficulty completing familiar tasks at home, at work, or at leisure

• confusion with time or place

• trouble understanding visual images and spatial relationships

• new problems with words when speaking or writing

• misplacing things and losing the ability to retrace steps

• decreased or poor judgment

• withdrawal from work or social activities

• changes in mood and personality, including apathy and depression

• increased anxiety, agitation, and sleep disturbances

what pathologies dominate clinical dementia diagnoses?

mixed pathologies

vascular dementia

• early: impaired judgement, ability to make decisions, plan or organize, as opposed to memory

• later: difficulty with motor function, slow gait, and poor balance

• step decline

alzheimer dementia

• early

  • difficulty remembering recent conversations, names, or events

  • apathy and depression

• later: impaired communication, disorientation, confusion, poor judgement, behavior changes, and ultimately difficulty speaking, swallowing, and walking

lewy body

• associated with loss of neuron that produce acetylcholine and dopamine

• cognitive signs: visual hallucinations, fluctuating concentration & alertness

• movement problems: similar to PD

• behavior: depression, NPS, delusions paranoia

lewy bodies

abnormal deposits of the protein alpha-synuclein

frontotemporal denmetia

• young

• changes in social behavior

normal pressure hydrocephalus

• an abnormal buildup of CSF in ventricles

• results from: subarachnoid hemorrhage, head trauma, infection, tumor, unknown

• symptoms: dementia, gait dysfunction, and incontinence

• underdiagnosed

• treatment: shunt from brain to abdomen

LATE (limbic-predominant age-related TDP-43 encephalopathy)

• causes symptoms similar to Alzheimer’s, including problems with thinking, remembering, and reasoning

• underlying cause involves abnormal clusters of a protein called TDP-43

• tends ot affect people over the age of 80

screenign

mini cog

1. remember three unrelated words

2. draw clock with hands at 10 past 11

3. repeat the three previously stated words

clock in the box

in the blue box on the next page

• draw a picture of a clock

• put in all the numbers

• set the time to 10 after 11

MOCA

assesses cognitive domains

ten minutes ot administer

30 point max - more than 26 is considered normal

cognitive domains MOCA assesses

• attention

• concentration

• executive function

• memory

• language

• visuoconstructional skills

• conceptual thinking

• calculations

• orientation

what is memory

capacity to learn, connect experiences, and make sense of our lives

four stages of memory

1. encoding

2. storage

3. consolidation

4. retrieval

mechanisms

• process continuous sensory input

• long-term potentiation (LTP)

• long-term depression (LTD)

types of long-term memory

• implicit (nondeclarative)

• explicit (declarative)

localization of memory

• frontal lobe - short term

• M temporal - long term

• prefrontal - episodic memory

• distributed - semantic memory

• hippocampus - object recognition; spatial represention

• amygdala - emotion

limbic

• medial side of in temporal lobe cortex

• cingulate

• parahippocampal gyrus

• hippocampus

• amygdala

• helps to connect effectively

entorhinal cortex

key, gateway to hippocampal formation

genetic factors in AD

• twenty suspectibility genes

  • sporadic and familial forms

• APOE

  • late onset — 15% of population

    • 40% have APOE

    • about nine other genetic factors

• Amyloid precursor protein

  • early onset

• presenilin 1 and 2

  • early onset

role of ACh in brain

• memory

• attention

• arousal

• non-REM sleep

destruction to cholinergic neurons

project to neocortex and hippocampus

amyloid

• A beta

• outside the neurons

• form plaques

• influence the synapse

• ca’t release neurotransmitters

tau

tangles in the neuron

nongenetic factor for AD

• toxins

• viruses

• prions

• low level of education

• head trauma

location of a beta

basal cortex, hippocampus, neocortex

location of neurofibrillary tangles

entorhinal cortex, subiculum, denate gyrus

location of atrophy

• medial temporal lobe atrophy

• hippocampus

additional pathophysiology

• calcium dysregulation

• proteolysis failure

• altered cell signaling

• oxidative stress

• inflammation

progression of AD

specific and serial

• entorhinal area, hippocampus

• neocortex

what has greater hippocampal atrophy

MCI than normal

what has greater whole brain atrophy

AD greater than MCI

AD has less

metabolic functioning

AD has greater

damaged neurons

functional cortical networks

• default mode network

• salience network

default mode network

• internally directed attention

• autobiographical memory

  • thinking internally

salience network

• externally directed attention

• goal-oriented attention

• stimuli drives responses

progression of cognitive loss

• inattention

• inability to store new events (episodic)

• loss of verbal fluency, object naming (semantic)

• difficulty planning (frontal cortex)

• poor working memory (short-term)

• loss of simple language and motor skills

pharmocology

• acetyl cholinesterase inhibitors

• N-methyl D-aspartate antagonist

• combination

• natraceuticals

acetyl cholinesterase inhibitors

• eats at the synapse

• doesn’t work in brain

N-methyl D-aspartate antagonist

preserving glutamate

combination of medications

Aricept and Namenda

natraceuticals

• vitamens

• flavonoids - red wine, blueberries, dark chocolate

neuropsychoiatric symptoms

• agression

• agitation

• apathy

• depression

• psychosis

agression

in response to stimulus

• physical and verbal

agitation

drives caretakers crazy

• walking aimlessly

• pacing

• trailing

• restlessness

• repetitive actions

• sleep disturbance

apathy

• withdrawn

• lack of interest

• amotivation

• requires instantaneous interventions

depression

• sad

• tearful

• hopeless

• low self-esteem

• anxiety

• guilt

psychosis

• hallucinations

• delusions

• misidentification

negative consequences for person with demetia

• poorer quality of life

• greater ADL limitations

• increased safety concerns

• early nursing home placement

• more rapid disease progression

caretaker

• increased depression, burden, upset, and being overwhelmed

• increased need for vigilance and time spent caregiving

• poor quality of life

• increased cost to caregiver

person-centered care

• caregiver, individual, environment

• personal knowledge of the person with dementia

• conducting meaningful activities

• making well being a priority

• improving the quality of the relationships between the health care provider and the individual dementia

Person-centered approach to persons with dementia

• Maximize activity
  • Tap into preserved capabilities and previous interests
  • Set up activity and help initiate participation
  • Create routines and break tasks into simple activities

• Maximize communication
  • Allow sufficient time for responses
  • Provide simple (one step) commands or simple choices
  • Calm tone and use touch to reassure, calm, or redirect

• Enhance environment
  • Remove clutter but keep it interesting
  • Eliminate noisy distractions

Strategies for Care Providers

Assess the person in the situation
• Pain or discomfort, or unwell
• Tired, overstimulated, bored
• Lacking in social contact or anxious
• Embarrassed, ignored, or misunderstood
• Hallucinating, delusional
• Depressed

for better perfomance of ADLs

use compensatory models

for better executive functions

use restorative models

Examples of Compensatory PT Intervention Strategies

• Facilitate alertness and attention
• Calm tones, environment
• Facilitate exercise
• Facilitate opportunities for success
• Give exact verbal and nonverbal cues through multiple sensory channels
• Keep tasks short and provide rests and adequate time for performance
• Focus on a single task
• Avoid tasks that stress memory
• Use procedural memory and routine
• Use environmental cues, signs, notes

key features of delirium

• Disturbance of consciousness—attention deficit
• Poor ability to follow directions
• Easily distracted
• Rapid onset
• Fluctuating course

Predisposing Factors

• Dementia or preexisting cognitive impairment
• History of delirium
• Functional impairment
• Sensory impairment; e.g., vision impairment and hearing impairment
• Comorbidity or severity of illness
• Depression
• History of transient ischemia or stroke
• Alcohol abuse
• Older age

Precipitating Factors

• Polypharmacy, use of psychoactive or sedative-hypnotic drugs
• Use of physical restraints
• Use of bladder catheter
• Infection
• Any iatrogenic event
• Major surgery
• Trauma or urgent admission to hospital
• Coma
• Physiological and metabolic abnormalities—high blood-urea nitrogen:creatinine ratio, abnormal sodium, glucose, or potassium concentrations in serum, hypoxemia, or metabolic acidosis

For cognitive impairment

Reorientation strategies
• Family involvement; companions
• Glasses and hearing aids
• Redirection without confrontation of delusions or hallucinations

For immobilization

Maintain safe mobility
• No physical restraints
• Encourage self-care and mobility
• Avoid bedrest

For sleep deprivation

Normalize sleep-wake cycle
• Discourage napping
• Expose to bright light during the day

Psychoactive medications

• Restrict use
• Use nonpharmacological protocols for sleep management

Vision and hearing impairment

• Provide vision or hearing aids
• Instruct staff in communication techniques

dehydration

• Volume repletion
• Early recognition

heart and brain

must work together