Learning disabilities

Question 1

Define learning disability

Answer 1

label for identifying groups of people in need of care and support, who are at special risk of developing behavioural disturbances and psychiatric disorders.

Question 2

What is an intellectual disability?

Answer 2

Must have

1. Impairment of cognitive function - IQ < 70
2. Impairment of social functioning
3. Presenting before 18 years

Question 3

How is intellectual disability categorised?

Answer 3

50-69 Mild Language fair, reasonable level
independence

35-49 Moderate Better receptive than expressive language

20-34 Severe Increased sensory and motor defecits
50% have epilepsy

<20 Profound Developmental age = 12 months

Question 4

What is the aetiology of intellectual disability?

Answer 4

• Prenatal (70%)
o Genetic
 Single gene disorder, X linked - Fragile X
 Single gene disorder, autosomal dominant - Tuberous sclerosis
 Chromosomal disorder - Down’s
 Imprinted gene disorder - Prader Willi syndrome
 Unknown but strongly hereditable - Autistic spectrum disorder

o Intrauterine
 Toxins - fetal alcohol syndrome.
 Infections - rubella

• Perinatal (20%)
 Hypoxia - Cerebral palsy
 Neonatal infection, neonatal jaundice

• Postnatal (10%)
   Trauma
   Neglect/extreme deprivation/child abuse
   Infection – meningitis, tumour, S/E of treatment for either

Question 5

How does intellectual disability present?

Answer 5

• The presentation will depend on the nature of the cause and severity.
• Those diagnoses associated with major structural anomalies may be diagnosed during intrauterine development or at birth.
• Others may be diagnosed by early abnormalities in development for instance, difficulties with feeding, abnormal muscle tone or failure to achieve early developmental milestones.
• There are often abnormalities with various aspects of behaviour.

Question 6

What is the most common specific cause of learning disabilities?

Answer 6

Down’s Syndrome

• DS is associated with borderline intelligence of mild ID in 15%, with the rest having moderate or severe impairments.

Question 7

What is downs syndrome and how common is it?

Answer 7

•	1 in 700 live births
•	TRISOMY 21
o	(95% = primary non-disjunction in maternal meiosis)
o	others
	balanced and unbalanced translocation
•	balanced = high risk of recurrence 
	mosaicism
•	generally milder, may not be diagnosed

Question 8

What symptoms/complications can you get in downs?

Answer 8

o congenital heart defects in 40%
o hypothyroidism
o characteristic facial appearance
o increased risk Alzheimer’s
• Psychiatric comorbidities are relatively common in those with DS:
o with ADHD and conduct disorder occurring at  rates in children
o whilst 25% of adults with DS will have a psychiatric diagnosis
 usually depression.
• DS have  BP, low levels of atheroma, and vascular dementias are uncommon.

Question 9

What is autism spectrum disorder and how common is it?

Answer 9

pervasive developmental disorder, starting in early childhood and persisting throughout life.
• It is being increasingly recognised and current prevalence estimates across the whole population suggest a combined frequency for all ASDs (inc. atypical and Asperger’s syndrome) of ~1%.

Question 10

What are the core features of ASD?

Answer 10

o absent, delayed or abnormal use of verbal and non-verbal language
o difficulties in developing reciprocal social relationships
o narrow and restricted range of interests
o absence of symbolic play (imagination)
• However in those with severe ID, the impairment of language and communications skills often associated with such severe intellectual deficits may make a specific diagnosis of autism more difficult.

Question 11

what can also be present in ASD?

Answer 11

• Language and social communication problems are central to many of the difficulties faced by people with autism, isolating them from those around them and leading to their exclusion from communal life.
• In addition, there are increased rates of challenging behaviour, a collection of symptoms that may include aggressive actions directed at self or others, more fully described below.
o Likely due to the difficulty in understanding and meeting the concerns and needs of those with ASD & ID that cannot communicate
• ASDs are also associated with increased rates of psychiatric conditions and epilepsy.
o Increased risk schizophrenia in high functioning ASD
o severe autism and low IQ - high epilepsy rates

Question 12

What is prader willi syndrome and how common is it??

Answer 12

• Prader Willi syndrome (PWS) is a genetically determined neurodevelopmental disorder that results from the absence of expression of one or more as yet unidentified ‘maternally imprinted/paternally expressed’ genes located on chromosome 15.
• 1 in 50,000

Question 13

How does Prader willi present?

Answer 13

o extremely hypotonic
o failure to thrive
 requiring assisted feeding.
• As early as two years of age, the presentation changes to the phenotype that characterises the remainder of child and adulthood
o mild developmental delay
o tendency to skin pick
o most significantly, OBESITY
 consequence of extreme difficulty in controlling eating behaviour
 insatiable
o Later, short stature and a failure of normal secondary sexual development become apparent, as do behavioural and psychiatric problems.

Question 14

How well do prader willi patients function?

Answer 14

• Most people with PWS have a mild ID with an average IQ score of 60, with good spoken language and adequate functional abilities.

Question 15

What are the complications and mortality in prader willi?

Answer 15

• PWS is associated with DM, sleep and respiratory disorders.
• Yearly mortality = 3% (mainly associated with obesity related morbidity).

Question 16

What is the most common single gene cause of intellectual disability?

Answer 16

Fragile X

Question 17

How common is fragile X?

Answer 17

• 1 in 5000 males.

* Although X linked, it is also responsible for mild to moderate ID in 1 in 7000-10,000 females in the UK.

Question 18

What symptoms are there in Fragile X?

Answer 18

• In affected boys, physical signs include:
o mild facial dysmorphia with long face and large ears
o macroorchidism by around the onset of puberty
• However, these signs are not sufficiently constant or specific to be pathognomonic.
• Intellectual and behavioural signs include:
o delayed language acquisition
o impaired numerical and visuospatial skills
o behavioural problems inc. autism like behaviours of social anxiety and aversion to eye contact in around 30%.
• Hyperactivitiy and self-injury when excited or frustrated (for instance hand biting, scratching) are also recognised.

Question 19

What are commmon physical comorbidities in intellectual disability?

Answer 19

• Poor oral hygiene with dental disease.
• Gastrointestinal problems incl. gastro-oesophageal reflux and constipation.
• Epilepsy.
• These may lead to a variety of manifestations of distress including behavioural symptoms ranging from self-injury (for instance hitting your own face repeatedly), to hitting out at those that try to get close to apparently loss of previous skills.
• Motor problems, partial sightedness and hearing disorders may not be diagnosed without specialist assessment.
• Epilepsy is common in those with ID (15% in mild to moderate, 30% in severe)  individuals are more likely to have multiple seizure types, to have lower rates of seizure freedom on antiepileptic medication and to have higher rates of sudden death in epilepsy (SUDEP).
• In those with tuberous sclerosis (an autosomal dominant disorder involving one of two genes  TSC1 or TSC1) and leading to the development of multiple haematomas in brain and other organs), severe seizures in infancy may be the presenting complaint.

Question 20

What are common psychological comorbidities in intellectual disabilities?

Answer 20

• Overall psychiatric symptoms and psychiatric diagnoses exist more frequently in those with an ID than in the rest of the population.
• Relatively common conditions include affective disorders and autism.
• Affective disorders and schizophrenia are both considered to occur at least twice as often in those with ID as in the rest of the population and ADHD also occurs more frequently in adults with ID.
• Several behaviours that are core features of autism for instance obsessional need for sameness, with intolerance of variation or unpredictability, also occur in various syndromes of ID, often in association with severe impairment of IQ.
• DS is associated with higher rates of Alzheimer’s disease and there is an increased prevalence psychotic symptoms in people with Prader Willi syndrome
• Self-injury  It is also a common problem amongst those with more severe ID.
 In this group it often takes the form of biting, scratching or head banging.
 It may at times be understood as a self-stimulatory behaviour and can occur for a significant proportion of the time and may be hard to stop.
 However, when it develops in an individual for whom it is not habitual, it is important to consider the possibility of physical health problems, environmental changes and mood disturbance.

Question 21

Describe challenging behaviour

Answer 21

• Behaviour can be described as challenging when it is of such an intensity, frequency or duration as to threaten the quality of life and/or the physical safety of the individual or others and is likely to lead to responses that are reactive, aversive or result in exclusion.

Question 22

How common is challenging behaviour in ID and why can it occur?

Answer 22

prevalence of serious or aggressive challenging behaviour in those that have ID been estimated at ~10%.
• Challenging behaviour is often a presentation resulting from any of a variety of physical or emotional causes or environmental triggers.
• These may include pain (earache or toothache), changes in care staff or care routines or side effects from some prescribed medications.

CHALLENGING BEHAVIOUR IN THOSE WITH INTELLECTUAL DIABILITY IS LIKE DELIRIUM IN ELDERLY – FIND UNDERLYING CAUSE!

Question 23

How Should you communicate to those with ID?

Answer 23

 Those with mild to moderate ID will understand some language.
 Those with very little speech will often be aware of many social conventions and may well be able to make use of signs or other communication aids.
 Before greeting a patient with ID whom you have not previously met, ascertain their level of ability with respect to communication.
 Speak clearly and not to quickly.
 Use short, clear and unambiguous sentences.
 Time should be allowed for the content of each sentence to be absorbed, particularly if the content is unfamiliar.
 Actual understanding of the communication should be regularly checked.
 At least until the level of a person’s awareness of their environment is established, it should be assumed that they expect to be greeted and where appropriate addressed directly and not simply referred to in a conversation between you and the carer.

Question 24

What are other important things to consider in the management of ID?

Answer 24

• There is an increased risk for a range of physical, behavioural and psychiatric comorbidities (these should be the focus of active management efforts).
• In all circumstances, it is important that the person with ID, if at all possible, understands what they can of the treatment and why they are receiving it.
• In the case of pharmacological or other physical treatments, it is important to appreciate that the person may not be able to report the presence of side effects.
• People with mild to moderately disability can often make good use of cognitive behavioural approaches as long as these are pitched at levels appropriate for them.
• For those with more severe impairments of function, behavioural management programmes can frequently lead to clinical improvements.
• Careful explanation, appropriate psychoeducation and on-going support will be very important, but then they always should be, regardless of who the patient is

Question 25

What is a good approach when tackling issues of consent in ID?

Answer 25

1. Obtain relevant background information: personal and medical history and accounts from informants.
2. Consider any current psychiatric/medical diagnoses.
3. Consider intellectual level, the presence of ID does not necessarily preclude capacity and examine intellectual functioning with respect to the specific decision to be made.
4. Enhance capacity if possible, for instance by providing information at the appropriate level of complexity and in the most accessible form for that individual. Assistance of a skilled speech and language therapist or psychologist may be appropriate.
5. Keep full clinical notes for the assessment.