The diagnosis of dementia in people who have sight loss - MMSE, a position statement

1. Introduction

The VISION 2020 UK Dementia and Sight Loss Interest Group is aware that sight loss may compound the experiences and impacts of dementia (and vice versa) and that diagnosis of dementia may be made more problematic when a person has sight loss (and vice versa). The effects of sight loss on dementia are not necessarily related to the cause of sight loss, which may include dementia itself, or any of a range of health conditions and not only an eye condition.

The most often frequently used tool to diagnose dementia or assess its severity is the MMSE (Mini Mental State Examination). It sometimes appears that diagnosis of dementia on the basis of the MMSE is taken as a conclusive indication of dementia.

Because some elements of the MMSE rely on vision people with sight loss, their families and the people who work with them, are concerned that the MMSE may not be appropriate or sensitive to their situation and that the results may not be valid.

This note provides people with sight loss, their families and the people who work with them information on best practice guidance on diagnosis of dementia and how to ensure that the effects of sight loss on the MMSE and on people’s confidence and comfort in its use are addressed.

2. Summary and next steps

NICE guidance makes clear that the MMSE should not be used alone as a tool for diagnosis or assessment of the severity of dementia, and that each person’s situation must be considered. NICE makes clear that clinicians must be fully aware of, and consider, any element of sight loss and the impact that may have on how the MMSE is used and its findings interpreted and the impact of its use on the confidence and comfort of people with sight loss.

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People with sight loss, their families and those who work with them, who are seeking advice or assessment about development of a dementia may need to ensure that the degree and effect of sight loss is clearly understood by clinicians. This should involve advising clinicians of each person’s vision and sight loss: description of sight loss, its cause, the effects on daily life and how long the person has had sight loss and the approaches or techniques they have used to live with sight loss.

At the same time it is important that people with sight loss, their families and those who work with them, are confident that the MMSE is not used alone. This may involve discussion with clinicians to understand the range of information and tools being used.

3. Guidance for diagnosis of dementia among people with sight loss

a) NICE

The National Institute for Health and Clinical Excellence (NICE) guidance on ‘supporting people with dementia and their carers in health and social care’ (CG 24) describes how a clinical cognitive assessment to identify dementia should be diagnosed. It states:-

“When using the Mini Mental State Examination (MMSE) to assess the severity of Alzheimer's disease, healthcare professionals should make sure that people from different ethnic or cultural backgrounds and people with disabilities have equal access to treatment.

“In some cases, healthcare professionals should not rely on the MMSE test − or not rely on it alone − to assess the severity of Alzheimer's disease. This may be the case when assessing people who:-

  • have learning disabilities or other disabilities such as deafness or blindness
  • have difficulty speaking (for example, after a stroke) or other difficulties with communicating
  • are not fluent enough in a language in which the MMSE test can be given if this means that the MMSE test will not fairly reflect the severity of the disease

“For these people, healthcare professionals should use a different method to judge the severity of Alzheimer's disease when deciding about starting or stopping treatment”. (

In summary, NICE advises that the MMSE should not be used alone, but in conjunction with approaches that take into account factors that may affect an individual’s response to the MMSE and therefore their diagnosis. It lists the following factors as those which should in particular be addressed:-

-educational level

-skills

-prior level of functioning and attainment

-language

-sensory impairment

-psychiatric illness

-physical or neurological problems

b) Other professional guidelines

  • Memory Services National Accreditation Programme (MSNAP) Standards for Memory Services Assessment and Diagnosis Editors: Emily Doncaster, Sophie Hodge and Martin Orrell. Second Edition October 2010. Pub. No. CCQI099. RoyalCollege of Psychiatrists.

-Section 3, Assessment and Diagnosis includes the need for a check of vision, hearing and mobility and recommends that interpretation of the scores from any cognitive tests (such as the MMSE) take full account of factors known to affect performance, such as sensory impairment, educational level, language and any other illness or health conditions.

  • Assessment scales in old age psychiatry:Alistair Burns et al (2004) 2nd ed. Martin Dunitz; ISBN: 1841841684

-This resource outlines different approaches and tools, including MMSE.

c) The ‘MMSE-blind’

Research in Germany (the Leipzig Longitudinal Study of the Aged - LEILA 75+) has investigated if and how the MMSE may be adapted to accommodate, and be more sensitive to, people who have sight loss. This showed that an adapted version of the MMSE which did not use any items that required visual processing was valuable and may be more sensitive. A version of the MMSE with age- and education-specific norms that has been validated as a screening tool for dementia has been developed.

  • Reischies, FM & Geiselmann, B (1997). Age-related cognitive decline and vision impairment affecting the detection of dementia syndrome in old age: The British Journal of Psychiatry, 171[5], 449-451
  • Adaptation of dementia screening for vision-impaired older persons. Administration of the MMSE (2002). Astrid Sonntag, Jeannette Bischkopf, Herbert Matschinger and Matthias C Angermeyer. Journal of Clinical Epidemiology (55; 2002 pp 909-915)

d) The Alzheimer’s Society

Alzheimer’s provides information about the process and tools that may be used (including factsheet 426, Diagnosis and Assessment, and factsheet 436 The MMSE).

While clinicians often consider the MMSE score as only one element in the process of diagnosing, or assessing the severity of, dementia there is concern that there is a degree of reliance on use of the MMSE and that this is (as NICE suggest) insufficient and may be a blunt instrument.

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