GS - Addenbrooke's Cognitive Examination Flashcards
What are the possible causes of cognitive impairment?
- Alzheimer’s disease
- Vascular conditions (e.g stroke, vascular dementia, multi-infarct dementia)
- Fronto-temporal lobe dementias
- Lewy Body dementia
- Parkinson’s disease
- Huntington’s disease
- Progressive Supranuclear Palsy
- Multiple sclerosis
- Traumatic brain injury
- Normal pressure hydrocephalus
- Toxic conditions (e.g. alcohol related conditions, effects of street drugs and social drugs, environmental and industrial neurotoxins)
- Infectious processes (e.g. HIV infection and AIDS, Lyme disease, Chronic fatigue syndrome, Herpes simplex encephalitis)
- Brain tumours
- Oxygen deprivation (e.g. following heart attack, carbon monoxide poisoning)
- Metabolic and Endocrine disorders (e.g. hypothyroidism and liver disease)
- Nutritional deficiencies (e.g. Vitamin B12 deficiency)
- Prescribed Medication
- Mood problems (e.g. stress, anxiety, depression)
- Psychiatric problems (e.g. psychosis)
- Delirium
- Infections (e.g. chest infection and urinary tract infection)
- Intellectual disabilities
- Pain and discomfort
What are the benefits of using the ACE-III ?
Standardised and reliable
Sensitive to early stages of Alzheimer’s disease
The memory tests reflect the importance of episodic memory characteristic of early Alzheimer’s Disease
Assesses memory recognition and verbal fluency, assisting differential diagnosis
Provides subscale scores for each cognitive domain it assesses
Cognitive screening tools offer a time-efficient, objective initial assessment of cognitive functioning
The ACE-III has been found to be reliable and valid in the assessment of dementia.
When should the ACE-III be used?
The ACE-III should be used with individuals aged 50 years or older who present with suspected cognitive impairment.
When should the ACE-III not be used?
If an individual is intoxicated or has taken non-prescribed medications their cognition is likely to be affected. Any results would therefore not be a reliable assessment of the person’s true ability.
If the patient has a known learning disability.
If the patient appears to be sedated to the extent that it is likely that s/he cannot attend properly.
If the patient is delirious or experiencing hallucinations.
If the patient is distressed about completing the test.
If the patient states they do not wish to complete the test (consent must be obtained prior to administration!)
When the patient is not sufficiently fluent in English to complete the test.
What are the issues that need to be considered when carrying out cognitive testing ?
Medications
There are numerous medications that are known to impact on an individual’s cognitive ability. The impact varies according to type of medication, dosage, polypharmacy and age of patient.
Alcohol and Drugs
If an individual is intoxicated or has taken non-prescribed medications their cognition is likely to be affected. Any results would therefore not be a reliable assessment of the person’s true ability.
Pain and discomfort
If an individual is in pain or discomfort this may impact on concentration and, as a result, they may fail to take in new information.
Head Injury
Cognitive impairment following head injury can vary widely between people. Cognitive difficulties can occur in any of the cognitive abilities. Impairment may be limited to one cognitive ability or affect several. Impairment will depend on the severity of injury (e.g. length of period of loss of consciousness or post-traumatic anmesia) and which parts of the brain are injured.
Learning Disability
Individuals with a learning disability are born with, or have acquired, cognitive impairments early in life. The ACE-III was devised for the general population; it should not be used with patients who have a known learning disability. The ACE-III cannot distinguish between long-standing intellectual impairments and those of more recent onset.
Mood and/or Psychiatric problems
It is possible that some individuals with mood and/or psychiatric problems will be cognitively impaired on screening tools. Mental health problems can affect concentration and motivation, and this can affect performance on a cognitive screening tool. Psychiatric difficulties can also impact on cognition, which can improve after treatment. In these instances, level of cognition may vary depending on the status of the individual’s mental health (severity of symptoms, psychiatric diagnosis) and the medications that have been prescribed.
What is the ACE-III?
The ACE-III is a cognitive screening tool. It was designed to be sensitive to the early stages of dementia
The ACE-III is made up of five subscales: Attention, Language, Fluency, Memory and Visuospatial; each subscale represents a cognitive domain.
The ACE-III subscale scores are summed to produce an overall total score (maximum 100 points).
The Mini-ACE (M-ACE) is a shorter version of the ACE-III, and it was developed for use in settings where administration of the full ACE-III is not practical. The total score of the M-ACE is 30, with higher scores indicating better cognitive performance. The administration of the M-ACE takes approximately 5 minutes, and scoring should not take longer than 1-2 minutes.
What is the ACE not?
The ACE-III is not a diagnostic tool. It should be an aid to diagnosis and only be used as part of a wider assessment process:
The results from cognitive screening tools are not sufficient to make a diagnosis of dementia and should only be used as part of a comprehensive assessment (Smith et al., 2008).
Screening tools should only be administered by an individual who can access appropriate clinical supervision
ACE-III cut off scores alone should not be used as a means of determining whether or not someone has dementia
The ACE-III should not form the basis of care planning decisions
The ACE-III should not be used as a means of determining capacity
ACE-III scores do not directly relate to the day to day functioning of an individual
What must you gain prior to the assessment and explain?
It is vital that you gain consent from the patient to complete the ACE-III prior to administration.
You must explain:
Why you want to administer it
Explain possible causes; e.g not sleeping well, physical conditions, pain, worry, medications or mood might impact exam
Possible outcomes from the assessment (e.g dementia as get older) and if score as expected, borderline or below scoring system
What it would/would not involve (won’t confirm outcome - e.g dementia, just a small test to allow if we need to investigate further)
Pro’s and con’s of completing - Pros; Getting to bottom of things, first steps. Cons; Will take 15 mins of time and may mean we need to investigate further which could lad to diagnosis down the line
Mention what happens in exam! No blood test, needles etc!
It is the patient’s choice to complete it and Informed consent must be obtained and can stop assessment at any time
When doing the test when or when would we not have someone else in the room?
When administering the ACE-III, ideally no one else should be present in the room (e.g. no family members or other professionals) as this can distract the patient.
The exception to this rule would be if a patient specifically requested someone else to be present (e.g. if a patient felt their anxiety levels would be reduced if their partner remained in the room during testing).
If a family member is present, explain to them that they should not give any hints or cues because this will invalidate the results.
The test should be completed in a quiet, non-distracting environment
You should ensure that there will be no interruptions during the administration
What should you remember before carrying out the test?
Remember to follow administration instructions as this is a standardised test - deviating from these can invalidate the results obtained!
Provide positive reassurance about the patient’s performance but do not say whether answers are right or wrong
Patients can find cognitive testing anxiety provoking, so minimise distress by maximising therapeutic rapport before commencing the assessment
If a patient appears very anxious during the test – ask if they want to stop, or discontinue independently if you feel distress levels are impacting on their performance
Patients are free to discontinue the test at any time
Allow the patient time to answer - responses do not need to be immediate
Check if the patient wears glasses/hearing aid and if these items are to hand
For patients with known literacy difficulties omit the following:
Language Comprehension: writing and reading items and do not total the language domain or ACE-III total as it is no longer out of 100
The ACE-III can be photocopied to A3 size for those with visual difficulties
Write down all responses on the record form – correct and incorrect responses
Do not score the ACE-III as you are administering it….. this distracts patients if they see scores
For ease of administration, instructions to be given to the patient are stated on the record form
What are the cut off scores?
For the ACE-III, the cut-off scores of 88 and 82 out of 100 are recommended for suspicion of dementia.
Cut-off scores of 25 and 21 out of 30 are recommended for the M-ACE.
The Exception
If a patient scores 89 or above you may still refer for further assessment if you have particular clinical concerns, or more specifically if it is the case that the patient has either had a high level of educational or occupational achievement in the past.
Clinical concerns: if the patient is presenting unusually during testing (e.g. disinhibited, significantly socially inappropriate, or impulsive), further specialist assessment may be indicated.
Clinical concern may also be raised by the patient or a relative’s description of their difficulties e.g. marked personality change or deterioration in activities of daily living.
What does the ace test assess?
a screening test to assess cognitive functioning
The ACE-III will not yield a reliable and valid result if the patient is?
The patient is;
- acutely confused or hallucinating
- intoxicated
- under the age of 50
- is recognised as having a learning disability
What can the ACE-III indicate?
indicate if individuals are scoring below where they should score for their age
Before administering the ACE-III you need to?
- explain why you would like the patient to complete it
- state that the patient can stop at any time
- discuss possible outcomes from the assessment
- gain consent from the patient to do it
