Professional Reference articles are designed for health professionals to use. They are written by UK doctors and based on research evidence, UK and European Guidelines. You may find the Memory Loss and Dementia article more useful, or one of our other health articles.
Treatment of almost all medical conditions has been affected by the COVID-19 pandemic. NICE has issued rapid update guidelines in relation to many of these. This guidance is changing frequently. Please visit https://www.nice.org.uk/covid-19 to see if there is temporary guidance issued by NICE in relation to the management of this condition, which may vary from the information given below.
Things to consider when screening for cognitive impairment
Screening for dementia is not recommended for the general population. However, healthcare professionals should be aware of clinical features that may suggest cognitive impairment and should also be aware of the risk factors of dementia in people with conditions such as Down's syndrome and other learning disabilities, after a stroke and in Parkinson's disease. General practitioners need to be able to recognise cognitive impairment and possible dementia using:
- History taking.
- Cognitive and mental state examination.
- Physical examination and other appropriate investigations.
- A review of medication in order to identify and minimise use of drugs, including over-the-counter products, which may adversely affect cognitive functioning.
The rest of this article deals with the screening tests that can be used to detect cognitive impairment. The limitation of such cognitive function tests should be recognised and one UK study found that increased use of the tests was not reflected in an increase in the hospital diagnosis of dementia.
Screening tests for cognitive impairment can adequately detect dementia but there is no strong evidence whether interventions for patients or their carers have a clinically significant effect for people with cognitive impairment detected earlier. However, early diagnosis allows the person to plan ahead while they still have the capacity to make decisions about their future care, enables the person and their family members to receive timely practical information, advice and support, and allows access to available drug and non-drug treatments which may improve cognition, improve quality of daily life and delay institutionalisation.
Clinical assessment for cognitive impairment
- Clinical cognitive function tests in those with suspected dementia should include examination of attention and concentration, orientation, short-term and long-term memory, praxis, language and executive function.
- As part of this assessment, formal cognitive testing should be undertaken using a standardised instrument. For the purposes of screening in primary care, a test should be short, simple and easy to learn, and perform with high sensitivities and specificities.
- Those interpreting the scores of such tests should take full account of other factors known to affect performance, including educational level, skills, previous level of functioning and attainment, language and any sensory impairments, psychiatric illness or physical/neurological problems.
- Formal neuropsychological testing should form part of the assessment in cases of mild or questionable dementia. Many of the standard cognitive tests are designed for measuring impairment in older adults of average ability, whose cognitive abilities are generally slightly different in range and strength from those under 65 years. In the case of younger (or highly able older) people, a review by a specialist Cognitive Neurology team or a Clinical Neuropsychologist is recommended, as they have the tools to make diagnoses that are very frequently missed by the standard test protocols.
- At the time of diagnosis of dementia and at regular intervals subsequently, assessment should be made for medical comorbidities and key psychiatric features associated with dementia, including depression and psychosis, to ensure optimal management of co-existing conditions.
The General Practitioner Assessment of Cognition (GPCOG)
The GPCOG consists of cognitive function test items in addition to historical questions asked of an informant. It has been considered to be reliable and superior to the Abbreviated Mental Test (AMT) and to the Mini Mental State Examination (MMSE), in detecting dementia[4, 5]. However, the research on which this opinion is based was conducted some time ago, and the results of a more up-to-date systematic review are awaited
The Mini Mental State Examination
The MMSE was developed by psychiatrists and is highly regarded[6, 7]. It has some methodological issues and may discriminate positively for those with a higher level of educational attainment. There is no strong evidence to support the use of MMSE as a stand-alone test for the identification of patients with mild cognitive impairment (MCI) who may develop dementia.
The Six-item Cognitive Impairment Test (6CIT)
Developed in 1983, the 6CIT is relatively unknown, although because of recognition by The Royal College of General Practitioners together with new computerised versions, its usage is increasing.
The 6CIT is a much newer cognitive function test than the AMT (see 'Abbreviated Mental Test (AMT)', below) and it would appear to be culturally and linguistically translatable with good probability statistics; however, it is held back by its more complex scoring system. One study reported that it excluded dementia accurately in an older Emergency Department population. The National Institute for Health and Care Excellence (NICE) recommends it as one of the validated tests for use in a non-specialist setting.
Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE)
The questionnaire asks how the patient compares today with ten years ago in various activities - eg, remembering birthdays and recalling conversations.
Abbreviated Mental Test (AMT)
The AMT is a quick-to-use screening test that was first introduced in 1972 but is less widely used today. Developed by geriatricians, this is probably the best-known test in general hospital usage; however, it lacks validation in primary care and screening populations.
Its disadvantages are the ability to be confounded by intelligence, age, social class, sensitivity of hearing and history of stroke. A four-point AMT has been developed which should be easier to administer than the original ten-point version and may obviate some of these problems.
Test Your Memory (TYM) Test
This is a useful cognitive function test, particularly where clinician time is limited. It is advocated by NICE as a validated test suitable to be used in a non-specialist setting. The test involves:
- Ability to copy a sentence.
- Semantic knowledge.
- Verbal fluency.
- Visuospatial abilities.
- Recall of a copied sentence.
The ability to do the test is also scored.
The 10-point cognitive screener (10-CS)
- The 10-CS involves three temporal orientation questions (year, month, date), a three-word recall, and a four-point scaled animal naming task.
- One point is scored for each of the temporal questions and each word recalled, and the scores for the animal naming task range from 0 points for 0-5 animals, to four points for 15 or more animals.
- A score of eight or more is normal, 6-7 suggests possible cognitive impairment, and 0-5 suggests probable cognitive impairment.
- This is comprised of three temporal orientation questions (year, month, day of the week) and a three-word recall.
- Each correct response scores one point for a total maximum of six points.
- Two or more errors are considered high risk for cognitive impairment.
Memory Impairment Screen (MIS)
- At the beginning of the assessment the person is shown four words. The person is then given a category and requested to identify which word fits into that category. This is completed for all four words and it is explained that they will be asked to remember the words in a few minutes. A distractor activity is performed for two or three minutes (for example, counting to 20 and back, counting back from 100 by 7, spelling the word 'world' backwards) and then the person is asked to recall the four words.
- The maximum score is 8 (two points for each word recalled without prompting and one point for each word that requires prompting). A score of 5-8 indicates no cognitive impairment, and a score of 4 or less indicates possible cognitive impairment.
- This consists of two components: a three-item recall test for memory and a clock drawing test.
- There is one point for each word remembered after the clock has been drawn, and two points for a normal clock.
- A total score of 3, 4, or 5 indicates lower likelihood of dementia but does not rule out some degree of cognitive impairment.
Further reading and references
Hayat SA, Luben R, Khaw KT, et al; The Relationship Between Cognitive Performance Using Tests Assessing a Range of Cognitive Domains and Future Dementia Diagnosis in a British Cohort: A Ten-Year Prospective Study. J Alzheimers Dis. 202181(1):123-135. doi: 10.3233/JAD-210030.
Potts C, Richardson J, Bond RB, et al; Reliability of Addenbrooke's Cognitive Examination III in differentiating between dementia, mild cognitive impairment and older adults who have not reported cognitive problems. Eur J Ageing. 2021 Sep 22:1-13. doi: 10.1007/s10433-021-00652-4.
Dementia; NICE CKS, May 2021 (UK access only)
Menon R, Larner AJ; Use of cognitive screening instruments in primary care: the impact of national Fam Pract. 2011 Jun28(3):272-6. Epub 2010 Nov 29.
Lin JS, O'Connor E, Rossom RC, et al; Screening for cognitive impairment in older adults: A systematic review for the U.S. Preventive Services Task Force. Ann Intern Med. 2013 Nov 5159(9):601-12.
Brodaty H, Low LF, Gibson L, et al; What is the best dementia screening instrument for general practitioners to use? Am J Geriatr Psychiatry. 2006 May14(5):391-400.
Milne A, Culverwell A, Guss R, et al; Screening for dementia in primary care: a review of the use, efficacy and quality of measures. Int Psychogeriatr. 2008 Oct20(5):911-26. Epub 2008 Jun 5.
Tsoi KK, Chan JY, Hirai HW, et al; Cognitive Tests to Detect Dementia: A Systematic Review and Meta-analysis. JAMA Intern Med. 2015 Sep175(9):1450-8. doi: 10.1001/jamainternmed.2015.2152.
Mitchell AJ, Malladi S; Screening and case finding tools for the detection of dementia. Part I: Am J Geriatr Psychiatry. 2010 Sep18(9):759-82.
Arevalo-Rodriguez I, Smailagic N, Roque-Figuls M, et al; Mini-Mental State Examination (MMSE) for the early detection of dementia in people with mild cognitive impairment (MCI). Cochrane Database Syst Rev. 2021 Jul 277:CD010783. doi: 10.1002/14651858.CD010783.pub3.
O'Sullivan D, Brady N, Manning E, et al; Validation of the 6-Item Cognitive Impairment Test and the 4AT test for combined delirium and dementia screening in older Emergency Department attendees. Age Ageing. 2018 Jan 147(1):61-68. doi: 10.1093/ageing/afx149.
Dementia: assessment, management and support for people living with dementia and their carers; NICE Guideline (June 2018)
The Demegraph; Biostatistics Unit, University of Melbourne
Schofield I, Stott DJ, Tolson D, et al; Screening for cognitive impairment in older people attending accident and emergency using the 4-item Abbreviated Mental Test. Eur J Emerg Med. 2010 Dec17(6):340-2.
Hancock P, Larner AJ; Test Your Memory test: diagnostic utility in a memory clinic population. Int J Geriatr Psychiatry. 2011 Sep26(9):976-80. doi: 10.1002/gps.2639. Epub 2010