Developmental Disabilities Overview

Developmental Disabilities

• The term "developmental disabilities" (DD) is used in Ontario to describe certain conditions, but it is important to use it cautiously to avoid stigmatizing or marginalizing individuals.
• There are many terms that have been used in the past to describe DD, some more appropriate than others.
• DD can be caused by one or more health conditions, including syndromes and contributing factors.
• DD affects 2-3% of people worldwide, with 2/3rds experiencing mild to moderate cases and 1/3 experiencing severe to profound cases.
• The most common DD's in Canada are Autism, Fetal Alcohol Syndrome, Down Syndrome, Fragile X Syndrome, and 22q11 Deletion Syndrome.
• Approximately 25-50% of all developmental disabilities are caused by biomedical factors, most commonly genetic abnormalities.

Meaning of Developmental Disability

• Personal meaning: Focuses on an individual's unique strengths and needs.
• Literal meaning: Refers to the specific characteristics used to define the disability.
• Social meaning: Reflects society's tolerance, acceptance, and understanding of the disability, contributing to the broader social perception.
• Critical disability meaning: Highlights the limitations and shortcomings of the individual.
• Definitional meaning: Uses a very specific set of criteria to define the presence or absence of a DD.

AAIDD Defintion of Intellectual Disability

• Intellectual disability is characterized by significant limitations in both intellectual functioning and adaptive behavior, evident in conceptual, social, and practical skills.
• The disability must originate before the age of 18.
• Limitations in functioning should be assessed within the context of the individual's community, age, peers, and culture.
• Assessment should consider cultural and linguistic diversity and differences in communication, sensory, motor, and behavioral factors.
• Individuals with DD often possess strengths alongside their limitations.
• The purpose of describing limitations is to identify the necessary support needed for individuals with DD.
• With personalized support over time, individuals generally show improvement in their life functioning.

Diagnosing Developmental Disability

• Several diagnostic tools are used to assess DD, including:
  • DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, 5th edition)
  • ICD-11 (International Classification of Diseases, 11th Revision)
  • The Education Act (Ontario)
  • ICF-CY (International Classification of Functioning, Children & Youth)
  • ABAS-3 (Adaptive Behaviour Assessment System Third Edition)
  • Vineland-3 (Adaptive behaviour assessment)

DSM-5 Classification of Intellectual Disability

• DSM-5 defines intellectual disability as a disorder present during the developmental period marked by deficits in intellectual and adaptive functioning.
• Three criteria must be met:
  • Deficits in intellectual functions, confirmed by clinical assessment and standardized intelligence testing.
  • Deficits in adaptive functioning, resulting in problems meeting personal independence and social responsibility standards.
  • Onset of intellectual and adaptive deficits during the developmental period.

Specifiers for Intellectual Disability in DSM-5

• Specifiers, such as age of onset, severity ratings, medical conditions, genetic conditions, or environmental factors, provide a detailed clinical description.
• Severity levels include Mild, Moderate, Severe, and Profound.

Education Act (Ontario) and Exceptionalities

• The Education Act (Ontario) designates students as "exceptional" within five categories: Behaviour, Communication, Intellectual, Physical, and Multiple.
• These designations are legal definitions and may not be equivalent to clinical diagnoses.
• The Identification, Placement and Review Committee (IPRC) process, governed by Regulation 181/98, determines whether a student is exceptional.

Severity Levels of Intellectual Disability

• Mild (85%): Typically not identified until early elementary years, may overrepresent minority groups, develop social and communication skills, and live successfully in the community with support.
• Moderate (10%): Often identified during preschool years, many individuals with Down syndrome fall into this category, benefit from vocational training, and can perform supervised work in adulthood.
• Severe (3-4%): Often associated with organic causes, identified at a young age, delays in development and visible physical features are present, require special assistance throughout their lives, and often live in group homes or with their families.
• Profound (1-2%): Identified in infancy due to significant developmental delays and biological anomalies, learn only basic communication skills, require intensive training, and need lifelong care and assistance.

Understanding Developmental Disabilities

• Evolving Perspectives: Previously, developmental disabilities were categorized based on intellectual abilities, communication, and behavior. Now, there's a shift towards a more nuanced understanding.
• Three Perspectives:
  • Legal Status: Individuals with disabilities often had to relinquish certain rights and privileges to access services, resulting in a different legal status.
  • Biomedical: Focuses on providing institutional care, following strict rules and regulations. Often deficit-driven.
  • Social and Human Rights Model: Examines the impact of social structures on individuals with disabilities, advocating for equality.

Developmental Disabilities in Ontario

• Legislative Changes: The Services and Supports to Promote the Social Inclusion of Persons with Developmental Disabilities Act, 2008 replaced the Developmental Services Act.
• New Definition: Emphasizes functional limitations in cognitive and adaptive functioning beyond IQ. Focuses on life-long impact and affecting areas of major life activity.
• Person-Centered Approach:
  • Encourages personalized planning with individuals expressing their specific needs and goals.
  • Aim is to promote independence and participation in community activities.
• Direct Funding: Allows individuals and families more choice and flexibility in accessing services.

Disability Rights in Canada

• Canadian Charter of Rights and Freedoms: Safeguards equality for all Canadians, regardless of disability, race, religion, sex, or age.
• Canadian Human Rights Act (1977): Protects against discrimination based on disability in employment and services provided by the federal government, First Nations governments, and certain private businesses.

Comorbidity: Mental Health and Developmental Disabilities

• Dual Diagnosis: Refers to the presence of both a developmental disability and a mental health disorder.
• Common Mental Health Disorders: Individuals with developmental disabilities experience a similar range of mental disorders as the general population, including mood disorders, anxiety, adjustment problems, personality disorders, and ADHD.
• Behavioral Challenges: Individuals with co-occurring conditions often exhibit behavioral challenges like aggression, self-harm, attention difficulties, and oppositional behaviors.
• Higher Prevalence of Autism: Individuals with developmental disabilities are more likely to have Autism Spectrum Disorder.
• Dual Diagnosis Consultation, Outreach Stabilization Service: This service in Windsor-Essex provides short-term stabilization for individuals 16+ with developmental disabilities and mental health disorders.

Factors Contributing to Mental Health Concerns

• Biological Factors: Brain injury, trauma, disease, or infection.
• Environmental and Psychosocial Factors: Poverty, isolation, lack of employment, limited social opportunities, weak social support, inadequate coping skills, and feelings of inadequacy.

Epidemiological Considerations

• Prevalence Rate: Research shows a higher risk of mental illness in the developmental disabilities population. Estimates suggest between 10% and 40% of adults with developmental disabilities experience mental health concerns.

Clinical Challenges

• Diagnostic Overshadowing: Tendency to under-recognize emotional or psychiatric disturbances in individuals with developmental disabilities.
• Behavioral Highlighting: Severe behavior may overshadow underlying mental health concerns.
• Communication Difficulties: Individuals with significant communication and cognitive impairments may struggle to express their distress.

Co-morbidity Beyond Mental Illness

• Individuals with developmental disabilities often face physical health issues, such as vision and hearing impairments.

Assessment in Developmental Disabilities

• Individuals with developmental disabilities are often overmedicated and undertreated due to caregivers' unfamiliarity with the nature of the disability.
• Caregivers may overlook or misinterpret certain concerns, such as withdrawn behavior or loss of interests, which could indicate depression.
• Professionals and paraprofessionals need specific training to understand the unique needs of this population.
• The Scientific Problem-Solving Model of Psychological Assessment involves six steps: problem clarification, planning, development, implementation, evaluation, and dissemination.
• Assessment in developmental disabilities aims to:
  • Identify strengths and needs
  • Determine appropriate interventions and services
  • Determine if an individual is experiencing a developmental disability or another condition
• The assessment process is complex, involving multiple professionals and extending over a prolonged period.
• Evidence-based strategies and interventions are recommended based on professional standards.
• Assessment may involve individuals and groups.
• Information gathered during assessment can include:
  • Health history
  • Social history
  • Characteristics
  • Skills
  • Knowledge and/or behavior
  • Environmental factors
• Assessment is crucial for:
  • Identifying and implementing supports for learning, physical health, and mental health
  • Improving an individual's daily functioning
• Reasons for individual assessments can include:
  • Identifying strengths and needs for educators
  • Identifying signs and symptoms of depression, potential causes, and available supports
  • Ongoing assessment for continuous support

Integrating Quality of Life in Assessment & Intervention

• Integrating quality of life concepts requires:
  • Examining the individual's life experiences and environment
  • Focusing on personal domains (family, friends, accommodations, work, leisure) and environmental domains (community resources, public safety)
• Priorities for action should be established:
  • Basic necessities
  • Satisfaction with important aspects of life
  • Achieving fulfillment and meaning
• Initial appraisal involves:
  • Determining individual strengths and needs
  • Identifying the individual's wishes
  • Determining the timeframe for assessment and intervention (short/long term, immediate/distant)
• Assessment methods should be:
  • Objective
  • Standardized
  • Incorporate personal perceptions from the individual and others
  • Align with the individual's values and priorities
  • Shape information towards the individual's goals
• Consider two key aspects:
  • Holism: Life is often viewed in parts but operates as an integrated whole.
  • Change over time: Acknowledge the dynamic nature of life experiences.

Five Essential Assessment Actions

• Attend to a situation or problem that has come to attention.
• Gather information about the situation or problem.
• Analyze strengths and needs.
• Understand factors that help or hinder improvement.
• Develop and implement plans to enhance positive factors and address hindering factors.

Formal Assessment Frameworks

• A formal assessment identifies needs and strengths in areas such as:
  • Intellectual functioning
  • Adaptive skills
  • Learning abilities and styles
  • Neurosensory functions
  • Speech and language skills
  • Health and medical conditions
  • Dental health
  • Nutrition
  • Neuropsychological issues
  • Life skills
  • Activities of daily living
  • Living environment
  • Available support

Diagnosis and the Regulated Health Professions Act (RHPA)

• The RHPA aims to:
  • Protect and serve the public interest
  • Create an open and accountable system of self-governance
  • Provide a modern framework for health professionals
  • Offer consumers freedom of choice
  • Improve quality of care
• Key features of the RHPA include:
  • Scope of practice for each profession
  • Controlled acts that require qualified practitioners
  • Health regulatory colleges to govern each profession
  • Health Professions Regulatory Advisory Council to advise the Minister of Health and Long-Term Care
  • Health Professions Appeal and Review Board for independent review of registration and complaint decisions.

Issues and Concerns in Making a Diagnosis

• Who is responsible for making the diagnosis?
• The reason for diagnosis must be understood.
• A formal diagnosis designates a specific term describing a condition.
• Diagnosis can be helpful in understanding an individual's needs and accessing resources, supports, and services.
• Overuse of diagnosis and associated clinical issues should be considered.
• Flexibility is allowed, especially in the DSM-5.
• Diagnoses are often considered permanent.

Challenges in Determining Disability

• Policies for diagnosing disabilities are inconsistent.
• Services require different aspects of the disability for eligibility.

Assessment & Treatment Formulation

• Assessment requires examining various factors including: identification of concerns, history of the concerns, client background information, supports background information, client examination, and support systems.
• A good assessment should identify strengths and needs within the system.
• Treatment focuses on reducing risk, decreasing organic contributions, decreasing stress, increasing competence, and a coordinated systems approach.

Adaptive Behaviour Assessments

• ABAS-3 assesses adaptive skills, including: communication, community use, functional academics, home/school living, health and safety, leisure, self-care, self-direction, and social.
• ABAS-3 results in scaled scores that range from Superior to Extremely Low.
• Vineland-3 is similar to ABAS-3 but also includes interview, parent/caregiver, and teacher forms.

Treatment Principles

• Treatment aims to maintain and improve life for those with disabilities.
• Effective intervention should: address specific needs, set clear and achievable objectives, be based on sound rationale, use methods agreeable to the individual, ensure smooth transitions, and follow up, if needed.

Types of Intervention

• Therapy types include active focused therapies, age-related therapies (IBI, ABA), communication, education & training, health & medication, lifestyle & personal support, and personal & skill development.

Intervention Specifics

• Strategies include: addressing sensory impairments, treating seizures, managing medical disorders, providing appropriate environments and expectations, increasing coping skills, communication skills, self-esteem, social support, and a coordinated systems approach with continuity of care.

Case Study: Michelle

• Michelle exhibited self-injurious behaviour (SIB) from a young age.
• Despite various interventions, her SIB persisted.
• Michelle was treated with high doses of antipsychotics and other psychotropics with limited success.
• A multidisciplinary assessment revealed a need for a coordinated system approach involving various local services.
• Regular meetings between care partners ensured continuity of care and minimized crises.
• Medication adjustments ultimately led to improvements in Michelle's quality of life and reduced SIB.

Key Points

• SIB arises from various circumstances and requires a stable and continuous setting for adequate assessment.
• A multidisciplinary assessment approach is critical.
• Antipsychotic medication prescription for challenging behaviours is no longer acceptable practice.

Psychological Assessment

• Is a system and problem-oriented process that is dynamic and conceptual.
• It consists of problem clarification, planning, development, implementation, outcome determination, and dissemination.

Psychological Testing

• A set of skills, tactics, and strategies used in the assessment process.

Percentile Scores

• Rank-order scores that indicate a person's score relative to scores of others in the same age group who took the test.
• Range from less than 1 to greater than 99.
• A score of 40 indicates that the person scored better than 40% of test-takers but lower than the remaining 60%.
• The average range is considered between the 25th and 74th percentiles.

Normal Distribution or Bell Curve

• Represents the distribution of intelligence in the population.
• The average range for IQ standard scores is 90-110, with 8-12 representing the average range for scaled scores on subtests.

Types of Validity

• Content Validity: Ensures a test adequately samples relevant aspects of the construct being measured.
• Criterion-Related Validity: Scores are shown to be related to specified external criteria, like performance on another measure or group membership.
• Construct Validity: Confirms that the test actually measures the construct it claims to assess.

Causes of Intellectual Disability

• Obvious Physical Damage: Includes Down Syndrome, disease, teratogens, prenatal malnourishment, and injury.
• No Obvious Signs of Brain Damage: A combination of genetic and environmental factors can contribute to intellectual disability.
• Environmental Factors: Low parental IQ and a disorganized, deprived home environment.

Conception and Genetics

• Conception marks the beginning of human development.
• A sperm fertilizes an ovum (egg cell) in the fallopian tube after the sperm travels through the vagina, cervix, and uterus.
• Both sperm and ovum have 23 single chromosomes, and during fertilization, their chromosomes combine to form 46 chromosomes (23 pairs) in the zygote.
• The Zygotic period, also known as the Germinal period.
  • The fertilized egg cell, called a zygote.
  • Cell division and differentiation into many cell types.
  • Pluripotent stem cells, which develop into various cell types.
• The Embryonic period (Week 2-8 of pregnancy)
  • Major organ systems develop.
• The Fetal period (End of Week 8 until birth)
  • Physical growth and maturation of organs.

Genetic Principles

• Chromosomes are thread-like structures carrying genetic material (DNA).
• DNA is a double helix structure that consists of genes, which hold instructions for various functions.
• Humans have 23 pairs of chromosomes, including sex chromosomes (X and Y).
• Mitosis: Normal cell division, resulting in two identical daughter cells with a full set of 46 chromosomes.
• Meiosis: Cell division specific to gametes (sperm and ova), with only half the number of chromosomes (23).
• Alleles: Alternative forms of a gene.
• Human Genome Project: Sequenced the entire human genome, including chromosome #20.

Genetic Inheritance

• Homozygous Pair: Two identical alleles for a specific gene, which can be dominant or recessive.
• Heterozygous Pair: Two different alleles for a specific gene, which can result in dominant or recessive expression.
• Phenotype: Observable characteristics of an individual.
• Genotype: Genetic blueprint, the combination of alleles inherited.
• Dominant-recessive pattern: A dominant gene always expresses its trait, while a recessive gene only expresses its trait when two recessive alleles are present.

Inheritance Patterns

• Polygenic Inheritance: Multiple genes interact to influence a single trait.
  • Ex: Eye color and height, with variations due to multiple genes.
• Multifactorial Patterns: Both genes and environmental factors contribute to the expression of a trait.
• Genomic Imprinting: Some genes have specific biochemical marks during ovum and sperm development, influencing their expression.
  • Ex: Prader-Willi syndrome (from the mother) and Angelman syndrome (from the father), both caused by defects on chromosome 15.
• Mitochondrial Inheritance: Genes passed only from mother to child.

Twins

• Identical (Monozygotic) twins: Result from the splitting of a single fertilized ovum, leading to two genetically identical individuals.
• Fraternal (Dizygotic) twins: Result from two separate eggs fertilized by two different sperm, resulting in two individuals with different genetic makeups.

Prenatal Development Problems

• Autosomal Disorders: Caused by errors on non-sex chromosomes.

  • Phenylketonuria (PKU): Lack of enzyme needed to metabolize phenylalanine, a protein, leading to intellectual disability.
  • Sickle-cell anemia: Red blood cells are sickle-shaped, causing anemia and other complications.
  • Tay-Sachs disease: Fatal genetic disease causing nerve damage and death by age 3.
  • Huntington's disease: Neurological disorder with degeneration of brain ventricles, usually starting in adulthood.

• Sex-Linked Recessive Disorders: Carried on the X chromosome and more common in males.

  • Hemophilia: Bleeding disorder due to missing clotting factor.
  • Red-green colorblindness: Inability to distinguish certain colors.
  • Fragile X syndrome: Most common form of inherited intellectual disability, affecting mental development.
  • Turner syndrome (XO): In females, characterized by short stature, heart problems, and cognitive delays.
  • Klinefelter syndrome (XXY): In males, characterized by underdeveloped testes, low sperm count, and language/learning difficulties.
  • Triple X syndrome (XXX): In females, characterized by slow development, poor verbal skills, lower intelligence.
  • XYY syndrome: In males, characterized by taller than average height, large teeth, and normal development.

Teratogens

• Environmental agents that disrupt embryonic and fetal development, causing birth defects.
  • Examples: Alcohol, tobacco, chemotherapy drugs, caffeine, cocaine, lead, mercury, radiation, prescription drugs, etc.
• Factors influencing teratogenicity:
  • Embryonic and fetal age (most vulnerable in early stages)
  • Dosage and duration of exposure.
  • Genetic susceptibility of the fetus and mother.

Specific Genetic Disorders

• Down syndrome (Trisomy 21): Caused by an extra copy of chromosome 21, it's the most common genetic cause of intellectual disability.
  • Distinctive facial features, physical abnormalities, heart problems, increased risk of seizures and Alzheimer's disease.
• Prader-Willi and Angelman syndromes: Both caused by defects on chromosome 15, but exhibit different symptoms depending on parental origin.

Genetic Factors in Mental Health Disorders

• Genetic components: Research indicates genetic links to psychiatric disorders.
• Higher proportion in individuals with developmental disabilities: Autism Spectrum Disorder (ASD) is an example.
• Environmental factors: Multiple births, older fathers, exposure to medications or infections during pregnancy, neurotoxins.
• Vaccination and autism: No causal link supported by scientific evidence.

Inherited Genetic Metabolic Disorders

• Defects in genes controlling metabolism: Affecting amino acids, sugars, carbohydrates, and nucleotides.
• Examples: Prader-Willi and Angelman syndromes.

Fragile X Syndrome

• Fragile X Syndrome is the most commonly inherited form of developmental and intellectual disability.
• Caused by a mutation in the FMR1 gene on the X chromosome.
• Occurs across all cultures, not related to mother's age at conception.

FMR1 Gene Mutation

• The mutation involves an expansion of CGG repeats in the promoter region of the FMR1 gene.
• Normal: 6-40 repeats
• Premutation: 55-200 repeats (may cause FXPOI and FXTAS but not IDD)
• Full mutation: 200+ repeats (gene may not work at all, often causes Fragile X Syndrome)
• The size of the mutation affects the severity of symptoms.

Symptoms of Fragile X Syndrome

• Intellectual & Learning:
  • Wide range of intellectual functioning, from mild learning disorders to severe IDD.
  • May experience delays in speech, language acquisition, short-term memory, and spatial awareness.
  • Difficulty with attention, hyperactivity, and anxiety.
• Physical:
  • Often not noticeable in infancy but may develop with age.
  • Features include a narrow face, large head, large ears, flexible joints, flat feet, and prominent forehead.
• Behavioral, Social, & Emotional:
  • Often experience anxiety and trouble in new or unexpected situations.
  • May have difficulty with eye contact, social interaction, and attention.
  • May display aggression, shyness, or autistic-like characteristics.
• Speech & Language:
  • Most boys experience speech and language difficulties, such as trouble speaking clearly, stuttering, or leaving out parts of words.
  • Girls usually have milder symptoms.
  • Some children with Fragile X may remain nonverbal throughout their lives.
• Sensory Sensitivity:
  • Many experience sensory issues like sensitivity to bright lights, loud noises, or certain textures.

Inheritance of Fragile X Syndrome

• Can be inherited from both mother and father who carry the mutated FMR1 gene.
• Males pass the mutated gene to all daughters but not sons.
• Females have a 50% chance of passing the mutated gene to both sons and daughters.
• Premutations can sometimes expand to full mutations during inheritance.

Diagnosis of Fragile X Syndrome

• Diagnosis typically involves a blood test to analyze the FMR1 gene.
• Prenatal testing (amniocentesis or chorionic villus sampling) can detect the mutated gene in the developing fetus.
• Average age of diagnosis for boys is 36 months and 42 months for girls.

Treatment of Fragile X Syndrome

• No single cure, but treatments aim to minimize symptoms.
• Early intervention is critical for optimal development.
• Key interventions include:
  • Educational support
  • Therapy services (occupational, physical, speech, and behavioral therapy)
  • Medications

Prevalence of Fragile X Syndrome

• 1 in 4,000 males and 1 in 8,000 females have Fragile X Syndrome.
• Fragile X premutations are more common, affecting 1 in 151 women and 1 in 468 men.