Care of People with Learning Disabilities

Dr James K. BetteridgeSeptember 2011

Outline• Introduction – Definition and Prevalence

• Case

• Classification

• Assessment

• Management

• Examples– Down’s Syndrome– Fragile X

Key Messages…RCGP

• In managing patients with learning disabilities, GPs should:– Be aware of likely associated conditions and

know where to obtain specialist advice– Understand how psychiatric and physical illness

may present atypically in patients with LD who have sensory, communication and cognitive difficulties

– Use additional skills of diagnosis and examination in patients unable to describe symptoms

Prevalence

• 2.5 x associated medical problems

• 3 x number of repeat prescription drugs prescribed by primary care

• Major economic burden on NHS, Social Services and social security system

DIAGNOSIS Per GP List of 2000

Down’s Syndrome 2

Fragile X 1

Cerebral Palsy 1

Autism Spectrum Disorder 1

Misc. 3

Definitions• WHO defines learning disabilities as: “a state of

arrested or incomplete development of mind.”• It is a diagnosis but is not a physical or mental

illness.• Three criteria are required before learning

disabilities can be identified:– Intellectual impairment– Social or adaptive dysfunction (Poor Life Skills)– Early Onset – birth/ early childhood

• Epidemiology – 1.5% of population

Case Illustration: Home Visit

Assessing IntellectIntelligent Quotient

(IQ)• Standardized tests in

different domains of intelligence– Median score is set at

100 with a standard deviation of 15

– This means 68% of population should have an IQ between 85 and 115

MENSA

• Derivation “mens” Latin for Mind, “mensa” Latin for Table

• A round-table society of minds

• Need IQ above 98th percentile to join – i.e. IQ above 145.

LD Classification

• Mild (IQ 50-70) – 80%– Not usually associated with abnormalities in

appearance or behaviour– Language, sensory, motor abnormalities are

mild or absent– Problems not apparent until school age– Difficulty coping with stress or more complex

areas of social functioning e.g. parenting, financial management.

– Usually live independently, engage in employment

LD Classification

• Moderate (IQ 35-49) 12%– Limited language

• Severe (IQ 20-34) and Profound (>20) 8%– Very limited communication and self-care skills– Associated physical disabilities

• Epilepsy 33%• Inability to walk 15%• Incontinence 10%

– May use non-verbal communication e.g. pointing, signing (Makaton)

Aetiology

• Mild LD– No specific cause– Bottom end of normal

distribution curve– Considerable genetic

contribution• Correlation between low

parental and low childhood IQ due to social and educational deprivation.

Aetiology

• More severe LD– Usually related to specific brain damage

• Antenatal– Genetic, Infective, Hypoxic, Related to maternal disease

• Perinatal– Prematurity, Birth hypoxia, Intracerebral bleed

• Postnatal– Infection, Injury (?NAI), malnutrition, hormonal,

metabolic, toxic, epileptic

Genetic Causes of LD

• Chromosomal– Down’s (Trisomy 21)– Klinefelter’s (XXY), Turner’s (X0), Fragile X

• Autosmal Dominant– Tuberose sclerosis, neurofibromatosis

• Autosmal recessive– Usually associated with a specific metabolic

condition e.g. Phenylketonuria

Down Syndrome

Down Syndrome• Commonest specific cause of LD• LD usually moderate or severe but mild in

15%• Chromosomal condition caused by the

presence of all or part of an extra 21st Chromosome

• Named after Dr John Langdon Down 1866• 1 in 733 births• More common in older parents due to

increased mutagenic effects on reproductive organs

D.S – Clinical FeaturesLearning disability• Language

– (Language delay – difference between understanding and expressing speech)

– Common to screen for hearing

• Motor skills– Fine motor skills lag behind – can interfere

with cognitive development– Gross motor skills vary – Walking age 2-4

• May benefit from physiotherapy to enhance

D.S. – Clinical Features

Screening for DS• Pregnant women in the UK are offered screening

for Down Syndrome• Combined Test:

– 85% detection rate, 5% False Positive– Ultrasound Scan (8-14/30 or first dating scan)

• Nuchal translucency (fat pad behind neck)

– Blood Test• Looks at Free Beta HCG and PAPPA (Pregnancy Associated

Plasma Protein A

• 2002 – Abortion rate of c. 92%

D.S. – Later Life

• Life expectancy 49 (2002)• People with DS surviving

beyond the age of 50 invariably develop neuropathological changes akin to Alzheimer’s disease visible on post mortem

• At least 50% have clinical dementia

Fragile X• Second most common cause of LD• 1 in 36000 male and 1 in 5000 female

births• Accounts for 8% of males with LD• Caused by expansion of a single

trinucleotide gene sequence (CGG)on the X chromosome

• Results in failure to express the protein coded by the FMR1 gene, which is required for normal neural development

Fragile X

Fragile X – Physical Features

• Large Head• Large Ears• Connective Tissue

Disorders• Low Muscle Tone• Flat Feet• Macro-orchidism• High arched palate• Mitral Valve Prolapse

Fragile X – Psychiatric Features

• Abnormal speech• Impulsivity and hyperactivity• Hand-biting, hand flapping• Poor eye contact• Unusual responses to sensory stimuli• 4% have autistic features• Women often have less severe behavioural

problems and only 1/3 have significant LD– WHY? Think genetics…..

LD and Psychiatric Illness

• Making diagnoses difficult due to coexisting language deficits

• Behavioural disturbance common :– Self-injurious, aggressive, inappropriate sexual

• Schizophrenia has prevalence of 3% in LD– Simple, repetitive hallucinations

• Depression and anxiety disorders higher than general population

Management of LD (1)

• Most people with LD live with their families• Support from primary care, educational and

social services• MILD

– Children - mainstream school with support– Adult – support to work in mainstream jobs

• Small minority with Severe/Profound and usually behavioural problems require residential care

• MDT approach to coordinate services – specialist psychiatric services– Mental illness, Physical illness, Finances, Housing

Management of LD (2)• Need for accessible information for patients• May face distress at realisation:

– They many not achieve full independence– Their parents are likely to die before they do– Issues surrounding sexuality

• Sensitive but frank communication at a level the patient can understand is important

• REMEMBER – people with LD, especially those living in institutions are at increased risk of physical, emotional and sexual abuse.