Dsm-5 Neurodevelopmental Disorders: Intellectual Developmental Disorder PDF

DSM-5 Neurodevelopmental Disorders: Intellectual Developmental Disorder September 24, 2024  Age 2 months hold head up 6 months babbling 7 months sit without support 9 months crawls 1 year single words, walks 18 months jo...

DSM-5 Neurodevelopmental Disorders: Intellectual Developmental Disorder September 24, 2024  Age 2 months hold head up 6 months babbling 7 months sit without support 9 months crawls 1 year single words, walks 18 months joint attention 2 years 2-3 word phrases 2-3 years theory of mind Developmental Milestones 4-5 years name letters 6 years decode simple words (Estimated based on epidemiological samples)  DSM-5 Neurodevelopmental Disorders Onset during developmental period Significant impairment in key domains of functioning or failure to meet key developmental milestones – Behavior/attention: ADHD – Cognitive: Intellectual Developmental Disorder – Social: Autism Spectrum Disorder – Learning: Specific Learning Disorder – Communication: Speech Sound Disorder, Language Disorder, Stuttering – Motor: Developmental Coordination Disorder, Tic disorder Also symptoms of excess – Excessive repetitive behaviors – hyperactivity Frequent comorbidity between disorders  What is IQ? Standardized normative measure of cognitive ability – Wechsler Intelligence Scale for Children – Stanford Binet “IQ” is an overall score that combines scores on measures of different aspects of cognitive functioning – Verbal Reasoning (vocabulary, general knowledge) – Nonverbal Reasoning (spatial problem solving, nonverbal puzzles) – Processing Speed (speed to complete simple tasks) – Some aspects of executive functions (working memory) Etiology and development – IQ scores are generally reliable and stable across development – Moderate genetic influences (at least 50%) that increase with age – Environment plays an important role as well – IQ scores must be used with care for children with less access to resources such as education, financial resources, nutrition, etc. Distribution of IQ scores in the population Average (IQ = 100) 68% of scores 95% of scores 70 85 100 115 130  DSM-5 Intellectual Developmental Disorder Previous names in DSM: Mental Retardation, intellectual Disability (Criteria have remained roughly the same) A) Deficient intellectual functioning (IQ < 70; about 2 in 100) – IQ score must be used with care for children with less access to resources such as education, financial resources, nutrition, etc. B) Adaptive Impairments – Conceptual Skills (understanding of abstract ideas like money) – Receptive and expressive language, academic functioning – Social understanding and functioning – Practical skills (dressing, toileting, self care, daily living) C) Onset of intellectual and adaptive deficits “during the developmental period” (before age 18) – Nearly always very early in development – Rules out adults with degenerative cognitive disease or traumatic brain injury  DSM-5 Intellectual Developmental Disorder: Associated Features and Comorbidities Depression and social withdrawal are common ADHD: up to 50% of cases – compare behavior to others the same mental age to avoid overdiagnosis Self-injurious or aggressive behaviors: 20% of cases – head banging, scratching, poke own eyes physical and health disabilities – seizure disorder: > 20% – Cerebral palsy: 20% – autism spectrum disorder: 10% DSM-5 Intellectual Developmental Disability Criterion A: Deficient Intellectual Functioning Reminder: The categorical approach loses information above and below the diagnostic threshold IQ = 70 Individuals Average with IDD (IQ = 100)  A dimensional approach to IDD in DSM-5: Severity Specifiers based on adaptive functioning IQ scores are not directly used to define groups, but do provide information about where groups fall on the distribution 70 50 35 Severe to profound IDD mild IDD Average (IQ < 35) (IQ = 50-70) IQ = 100 Moderate IDD (IQ = 35 - 49)  DSM-5 IDD with mild severity IQ typically 50 – 70 (not used to define group) About 85% of individuals with IDD Conceptual functioning – Impaired abstract thinking, academic functioning Social functioning – Immature social interactions and judgment – difficulty regulating behavior and emotions – Difficulty understanding social cues – May be easily manipulated by others Practical functioning and outcomes – Some support needed for daily tasks – may be able to live independently with support – Potentially hold a job that doesn’t emphasize conceptual skills – Need support for daily living skills like budget, raising family  DSM-5 IDD with moderate severity IQ typically 35 – 49 (not used to define group) About 10% of individuals with IDD Conceptual functioning – Substantial support needed across cognitive domains – Language and conceptual reasoning are often especially weak Social functioning – Marked difficulty in comparison to peers – Social interactions are much less complex – Difficulty understanding social cues; easily manipulated – Likely to require social and communicative support at work Practical functioning and outcomes – Extensive support needed for daily tasks and activities – Unlikely to live independently even with support – Potentially hold a job but require extensive support – Self-injurious behaviors in a small subset of individuals  DSM-5 IDD: severe or profound IQ typically less than 35 (not used to define group) About 5% of individuals with IDD Conceptual functioning – Attain few conceptual skills – Minimal or no language – Limited or no understanding of complex ideas – May use or understand single words or simple gestures Social functioning – Limited social interactions – typically with family or caregiver – Very limited understanding of social cues / gestures – Comorbid sensory or physical impairments limit social activities Practical functioning and outcomes – Need extensive supervision at all times – Dependent on others for all aspects of physical care and safety – Self-injurious behaviors in a significant subset of individuals  The “two group” model of IDD: Do these severity differences matter? Yes, the causes of mild IDD are different from the causes of severe – profound IDD (moderate is in the middle)  Family Studies of IDD: Select individuals with IDD with different severities. Where do their siblings end up on the distribution? Average IQ = 100 70 50 35 Severe to profound IDD mild IDD (IQ < 35) (IQ = 50-70)  Family Studies of IDD: Select individuals with IDD with different severities. Where do their siblings end up on the distribution? Average IQ = 100 Siblings of children with Siblings of children with severe to profound mild IDD share some of IDD score in the average range, suggesting the risk factors that lead they don't have the same risk factors as their to lower IQ sibling with IDD  DSM-5 Intellectual Developmental Disorder: The “Two group” approach Severe / profound IDD – Book describes as “organic” – most show a single identifiable "biological" cause Mild IDD – multiple genetic and environmental risk factors that each increase risk a small amount – Similar to every other disorder we talk about in this course Moderate IDD – More similar to mild IDD – Mixture of the two groups – some individuals do have an identifiable “biological cause” Organic (known) causes of severe to profound IDD Chromosomal disorders – An entire chromosome is missing or duplicated – the most common cause of severe IDD – Down syndrome: extra chromosome 21 – Klinefelter's syndrome: XXY – Turner syndrome: single X chromosome Specific genetic mutation – Fragile X: section of X chromosome vulnerable to breakage – Phenylketonuria (if untreated) – Thousands of other rare genetic syndromes (e.g., Prader-Willi and Angelman syndrome due to mutations on chromosome 15) – Our only clear examples of “single gene” conditions in this class Environmental risk factors – Major prenatal and birth complications – severe hypoxia (oxygen deprivation) at birth = one of the strongest environmental predictors) Chromosomes of an Individual with Down Syndrome (http://gslc.genetics.utah.edu) Chromosomes of an Individual with Fragile X Syndrome  Causes of Mild IDD: Multiple genetic and environmental influences (like other disorders we discuss in this course) Genetic influences – Siblings also show cognitive impairment – About 50% of the risk for mild ID is genetic – Dozens / 100s of genes, each causing small increase in risk Prenatal environmental risk factors – Maternal malnutrition or illness (influenza) during pregnancy – Maternal substance use during pregnancy (esp. alcohol) Birth complications – Hypoxia Later environment – medical conditions during early development (infection, trauma) – Low socioeconomic status – Low environmental enrichment  Prevention and Education Prenatal (prior to birth) education – Increase parental awareness and avoidance of risk factors (alcohol during pregnancy, exposure to lead or other toxins) Prenatal screening for genetic syndromes – Risk factors in family history (IDD or other syndromes in family) – Genetic screening of fetus to detect genetic abnormalities – Genetic counseling to support difficult decisions if needed Pharmacological Interventions Most important point: Medication does not cure IDD Meds can help to address co-occurring symptoms – Stimulants for comorbid ADHD – Antidepressants for comorbid anxiety or depression – Antiseizure medications and others for seizure disorders or severe self-injurious or aggressive behaviors  Psychological Interventions Family interventions – Parent education and support – Support for behavioral approaches with the child Early (usually behavioral) interventions – Supplemental education with repetition and structure – Behavioral approaches target basic skills (with parent help) – Focused language training (often with shaping) – Always tailored to the needs of the individual child School-based interventions and accommodations – Maximize inclusion in regular classroom – adapt curriculum and provide appropriate supports Adult residential care (a huge area of need) None of these are a cure, but lead to improved outcomes