Learning disability Flashcards
Define intellectual disability.
A developmental condition characterised by global impariment of intelligence and significant difficulties in socially adaptive functioning.
E.g. The presence of:
- reduced ability to understand new or complex information or to learn new skills;
- less able to cope independently;
- impairment that started before adulthood, with a lasting effect on development.
How common is ID?
- 2-3% prevalence
- Many never formally diagnosed
- F>M (3:2)
What is the aetiology of ID? List 2 antenatal, perinatal and postnatal causes of learning disability.
Usually no specific cause e.g. brain damage, genetic abnormalities, hypothyroidism. Multifactorial causes are common.
Name 3 syndromes associated with learning disability.
- Down syndrome
- Fragile X
- Fetal alcohol syndrome
List 5 clinical features of learning disability.
Presents in childhood but can be missed if mild
Abilities in … are delayed /reduced /absent:
- language
- schooling
- motor ability
- independent living
- social ability
- employment
Behavioural difficulties - 2o to combination of
- communication problems
- psychiatric illness
- physical illness
- epilepsy
- suboptimal support
What are the levels of ID?
- Profound: <20
- Severe: 20-35
- Moderate: 35-50
- Mild: 50-69
List 2 features of each level of ID.
- Mild
- Language: usually good, but its development may be delayed
- Cognitive, motor, social: many live and work independently.
- Moderate
- Language and cognitive abilities: less developed.
- Motor and social: Reduced self-care abilities and limited motor skills +/- long-term supported accomodation. Simple practical work should be achievable in supported settings.
- Severe
- Motor: Marked impairment of motor function.
- Language: Little/no speech in early childhood
- Cognitive and social: Simple tasks performed with assistance. Likely to require their family home or 24-hourstaffed home.
- Profound learning disability
- Language, cognitive, social, motor: Severely limited language, communication, self-care, and mobility. Usually require higher levels of support.
- Significant associated medical problems.
What are the components of the Wechsler Adult Intelligence Scale?
2 main components:
Verbal scales: general knowledge, digit span, vocabulary, simple arithmetic, comprehension, similarities
Performance scale: picture completion, arrangement, block design, digit symbol, object assembly.
What are the differential diagnoses in ID?
ASD - in Asperger’s there may be significant social deficits, communication difficulties and daily living issues
Epilepsy - frequent uncontrolled seizures can mimic persistent cognitive impairment
Brain injury or progressive neurological conditions*
Psychiatric - schizophrenia if severe and persistent, can lead to chronic impairment across many domains
Educational disadvantage/neglect - lacking opportunity to learn must be distinguished from LD.
*learning disabilities are neurodevelopmental disorders, occurring while the brain is still developing. If the patient presents late, it is important to decide whether or not impaired intellect was present before any adult illness.
What psychiatric comorbidities are common in those with ID?
~30–50% of people with LD have additional mental health problems and associated autistic spectrum disorders.
- Schizophrenia (3%)
- Mood disorders (x4)
- Autism (75% of those diagnosed have ID)
What are the physical comorbidities commonly present in ID?
- Obesity and poor diet
- Epilepsy
- Sensory impairment e.g. hearing loss, poor visual acuity
- Infections - less likely to be screened or have vaccinations
How do you assess for ID?
- Intellectual impairment - assessed using the WAIS IV: 11 subtests to derive Verbal IQ + Performance IQ = Full Scale IQ
- Adaptive/Social functioning - established via clinical interview and ABAS II (Adaptive Behaviour Assessment System)
Presence in childhood established using clinical interview and school reports
What is the average score for the WAIS scale?
- Average Range: 70-130.
- Average score: 100
What additional investigations should be done for ID?
- IQ testing: is there global intellectual impairment?
- Functional assessment of skills, strengths and weaknesses.
- Detailed developmental history from parents, e.g. details of pregnancy and birth, language and motor skills development, schooling, emotional development, and relationships. School reports are helpful.
- FBC, U&E, LFT, TFT, bone profile—to exclude reversible disturbances.
- Additional blood tests for known causes of learning disability.
- Investigations for associated physical illnesses, e.g. EEG for epilepsy.
- Genetic testing if appropriate.
What condition causing ID do these patients have?
Fragile X
