«Faculty for People with Intellectual Disabilities Dementia and People with Intellectual Disabilities Guidance on the assessment, diagnosis, ...»
Unexpected deterioration or changes in presentation or course should be investigated in case there are treatable additional physical or psychiatric co-morbid illnesses.
Atypical presentations in people with Down’s syndrome There have been anecdotal reports of people with Down’s syndrome in their teens or early adult life who deteriorate, often following a life event, and either never or, only after many months or years, recover. There have been limited reports in the literature (e.g. Worley et al., 2014) but the characteristics of the decline may superficially resemble that of dementia or depressive illness but it neither seems to progress (as would be expected with dementia) or resolve (as would be expected with depressive illness).
The clinical picture is dominated by the development of a general slowness in mental and/or physical activity, apparent loss of interest in previous activities, and a level of functioning that is below that previously observed. In some people the presentation may include autistic features. At present it is unclear how such problems should be best conceptualized. If depressive illness is a possible factor, a trial of anti-depressant medication may be indicated, with careful monitoring of outcomes. Other conditions such as Hashimoto’s encephalopathy catatonia and neurological diseases need to be excluded (Brodtmann, 2009, Jap & Ghaziuddin, 2011). Regular review of neuropsychological function is helpful in order to check that there is no progressive disorder such as dementia. Therapeutically the approach taken is primarily a rehabilitative one with attempts to help the person progressively back to their previous state of function.
People with intellectual disabilities without Down’s syndrome For those people with intellectual disabilities not due to Down’s syndrome, the picture may be variable. There is more likely to be a range of pathologies resulting in dementia, as is 22 Dementia and People with Intellectual Disabilities the case in the general population, and for the same reason differences in presentation and the course of the dementia.
Experience from the study of older people with Down’s syndrome suggests that the clinical presentation may be affected by an interaction between how brain development is affected due to having Down’s syndrome and the developing pathology of Alzheimer’s disease. The same is likely to be true among people with intellectual disabilities not due to Down’s syndrome as there will be a great variation across this population in terms of level of abilities. The following are likely to be useful guiding principles with respect to the presentation and course of dementia in those with intellectual disabilities not due to Down’s syndrome.
The presentation and course of dementia among people with mild intellectual I disabilities is likely to be similar to that which is observed in the general population.
The presentation and course of dementia in people with more severe intellectual I disabilities may initially be atypical and present with changes in behaviour and for this reason dementia may not be suspected. As the illness progresses careful questioning of staff and carers may identify evidence of developing memory and functional impairments or neurological symptoms such as incontinence and dysphagia.
The age of onset of dementia in this group of people may be a few years earlier than I is commonly found in the general population but not as early as in people with Down’s syndrome (Strydom et al., 2007).
As with those in the general population it is important to investigate the likely cause I of dementia as the full range of causes for dementia are likely to be found in this group of people and this may have important therapeutic and management implications.
There is evidence that the onset of epilepsy in later life for the first time may be a I marker for developing dementia in people with Down’s syndrome. Whether this is the case for other people with intellectual disabilities is uncertain but onset of epilepsy in later life for the first time should always be investigated and increasing difficulty controlling pre-existing epilepsy may be an indication for considering the possibility of developing dementia.
Key points The course of dementia in people with Down’s syndrome has been well studied, and I may be atypical with early development of behavioural or personality change, though memory problems are also prominent.
New onset of epilepsy or worsening of existing epilepsy in an older person with I Down’s syndrome should always raise the possibility of Alzheimer’s disease.
Diagnostic criteria are reliable in the intellectual disability population, but dementia I is more difficult to diagnose in those with severe disabilities or comorbid problems and may require sequential assessment. Clinicians should also keep in mind the slightly atypical presentation of dementia in people with Down’s syndrome.
A small number of young people with Down’s syndrome seem to present with I decline in their teens or early twenties, often with no clear aetiology.
People with intellectual disabilities without Down’s syndrome who develop I dementia may have the same range of pathologies as the general population.
Guidance on their Assessment, Diagnosis, Interventions and Support 23 Section 6 – Assessment There is great variability of functioning within the population of people with intellectual disabilities. Comparison with ‘peer-related’ norms is not possible as it is with mainstream dementia assessments. Assessment of decline needs to be personalised to each individual, with their own unique ‘baseline of functioning’ being the comparison when concerns arise. Holistic assessment should also encompass wider systemic issues (e.g. Care Quality Commission (CQC) concerns, Safeguarding Adult investigations). These issues can be identified through thorough informant and carer interview, direct observation as well as gathering knowledge from members of the multi-disciplinary team.
NICE Quality Standard 1, Dementia (NICE, 2010) states: ‘People with suspected dementia are referred to a memory assessment service specialising in the diagnosis and initial management of dementia.’ The process of assessment essentially has three stages that follow NICE guidance for dementia (NICE, 2006). For people with intellectual disabilities, this usually occurs within the context of the intellectual disability service rather than in mainstream memory services due to the specialist skills and expertise in assessing people with learning disabilities (Barrett & Burns, 2014).
Assessment should include a file review and systematic history-taking from the person and multiple informants across settings and services, who have known the individual for a significant period of time.
Assessment should include physical and mental state examinations, cognitive assessments and other investigations to enable the evaluation of present functioning and the identification of other possible causes of decline. The medical investigations should be guided by the clinical picture but invariably include investigations of a person’s basic physical state and specific tests, such as measures of thyroid function and B12, or specialist assessment of hearing and/or vision. Where the clinical picture is unusual, the diagnosis in doubt, or there are features that prompt concern (e.g. focal findings on neurological exam, a recent fall/head injury, rapid or sudden decline) a CT or MRI brain scan may be indicated (refer to Section 4 for detail regarding differential diagnosis and below for further details regarding scans).
The diagnostic process leads to a formulation that brings together all of the information from the various interviews, assessments and investigations and finally determines the likely cause of the observed clinical changes and sets them in the context of the individual. This forms the basis for making a possible diagnosis and developing an individualised care plan.
6.1 Assessment process The section outlines in more detail the key factors to be considered during the assessment process.
6.1.1 History and information gathering
• Nature of the presenting problem(s), origin, rate/pattern of progress (sudden or gradual), presence of seizures and other associated conditions, impact on the person’s overall functioning and personality.
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• History of significant physical and medical history including past and present medical conditions, e.g. diabetes, hypertension, thyroid or cerebrovascular disease, B12 deficiency.
• History of or current presence of psychiatric symptoms such as depression, anxiety or other mental health problems.
• Record developmental history and best level of historic functioning. Ascertain if there are any previous neuropsychological test data on record and compare data with previous assessment results. Record historic daily living skills, interests/hobbies/skills and details of personality.
• Family history: dementia or other mental health and medical conditions (particularly in first-degree relatives).
• Assess for psychosocial issues, changes or life events. These include house moves, health decline/death of loved ones, change of caregivers, changes to, or retirement from work/day services.
• Information gathering should be undertaken through a combination of informant interview (preferably with a family member, when relevant and appropriate) or an informant who has known the person well for a period of six months at least) and directly from the person where possible.
6.1.2 Mental state examination Observation of level of alertness, orientation to time, place and person, any evidence of alterations in consciousness, psychomotor activity, mood, thoughts, evidence of any abnormal mental beliefs or experiences, and perceptual abnormalities. Evaluation of memory and other cognitive functions via formal assessment (see below).
6.1.3 Physical examination Where possible a complete physical examination should be undertaken. This should occur in the context of primary care, although support may be provided by specialist services.
The key issues are:
• Cardiovascular system – focal deficits, evidence of cardiovascular accident etc.
• Detailed neurological examination (focal deficits, gait abnormalities, speech abnormalities, etc.).
• Endocrine system: signs of hypothyroidism.
• Careful recording of historic/newly added/current medications (with particular attention to those that are psychoactive, antiepileptic, sedating or anticholinergic).
Complete physical examination may be difficult in a significant proportion of individuals.
The physical health issues could be addressed in these individuals by a combination of:
• brief physical checks, e.g. blood pressure, pulse;
• observations for any evidence of physical health issues;
• observational tools (e.g. pain questionnaires); and
• information from carers, e.g. The OK Health Checks (Matthews, 2006), Health Action Plans (DH, 2001) or bespoke nursing assessments developed to meet the needs of local intellectual disability services can be used to structure this process.
Guidance on their Assessment, Diagnosis, Interventions and Support 25 6.1.4 Physical investigations
Recommended routine investigations are:
• full blood count;
• urea & electrolytes;
• blood sugar;
• thyroid function tests;
• liver function tests;
• B12 and Folate level;
• lipid profile; and
• sensory screening – vision and hearing.
Optional tests are:
• Electro encephalograph (EEG) – if there is evidence of the occurrence of seizures.
• Neuro-imaging: this may not be practical as a routine investigation for the assessment of dementia but may be of value when vascular dementia or other brain lesions are suspected (see section on ‘Neuroimaging’ below).
• Electro Cardiograph (ECG) – particularly if anti-dementia medication is to be used or there is evidence of cardiovascular problems.
6.1.5 Environmental assessment (see also Section 11)
• Quality of the person’s physical environment.
• Staffing levels (day and night).
• The mix of people with intellectual disabilities in the residential and day care settings.
• Quality and quantity of day activities.
• Staff characteristics: attitudes and competence, including consistency of approach.
• Scrutiny/review of historic/current support package.
Key points Carrying out investigations may be difficult in some individuals with intellectual I disabilities. In this situation, clinicians have to make a decision using information from the history, physical assessment and direct observation as to whether investigations are essential or not. There may be scope to work with the person to improve the chances of success in engaging with physical assessments (e.g. systematic desensitisation for blood tests, brain scans, eye-tests etc.).
Mental Capacity Act (2005) and its code of practice guidelines must be followed I where investigation is considered and the person is unable to consent and cooperate.
A minimum reactive dementia assessment should include/consider:
Physical health check.
I Longer-term and recent life events.
I Semi-structured interview exploring negative change in relation to functional skills, I memory, behavior, orientation, mood and consider potential alternatives for these changes.
Mental state examination (may utilise a depression or anxiety measure).
I Objective assessment of cognitive and adaptive skills and abilities.
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6.2 Information to support the assessment process Assessment tools for dementia in the general population are not appropriate for people with intellectual disabilities. For example, widely-used tools such as the Mini-Mental State Examination (MMSE) (Folstein & Folstein, 2001) or the Addenbrookes Cognitive Examination – 3rd Edition (Hodges, 2012) assume the pre-morbid level of functioning to have been within the average range.