Neurodevelopmental Disorders Flashcards
Intellectual Disability: DSM-IV Degrees of Severity
Mild: IQ 50-55 to ~70 Moderate: IQ 35-40 to 50-55 Severe: IQ 20-25 to 35-40 Profound: IQ <20 to 25 *shift away from the 70 cutoff in DSM-5...
Intellectual Disability: DSM-5 Criteria
- 3 criteria:
A) Deficits in intellectual functions (e.g., reasoning, problem solving) confirmed by clinical assessment and intelligence testing
B) Deficits in adaptive functioning; Without ongoing support, deficits limit functioning in one or more ADLs like communication, social participation, and independent living, across multiple environments.
C) Onset of intellectual and adaptive deficits during the developmental period
ID: DSM-5 Severity Specifiers
Defined on basis of adaptive functioning and not IQ
- Mild ID: similar to typically developing peers, often diagnosed later in school years, often minority or low SES, 6th grade academic skills, able to be independent adults
- Moderate ID: usually preschool years, usually develop communication skills, 2nd grade academic skills, moderate supervision for self-care, often unskilled labor/supervised workshop
- Severe ID: most cases organic causes, often physical/ambulatory problems, simple communication & self-care can be learned, require assistance throughout life, often live in supervised group homes & employed in workshop settings
- Profound ID: almost always identifiable organic cause, often nonverbal, intensive training needed for self-care, lifelong 24-hour care, usually residential facilities or group homes
Global Developmental Delay
- Under age 5
- Fails to meet developmental milestones in several areas
- Severity level cannot be reliably determined
- Can be given because IQ often not valid before age 5 so hard to give ID diagnosis
Unspecified Intellectual Disorder
- Over age 5
- When obtaining an accurate assessment is difficult or impossible due to child characteristics
- Use only in exceptional circumstances; acts as a placeholder for ID if hard to get diagnosis
ID Associated Features
- Can have similar personality and behavioral features found in others (but may have unique features based on ID etiology)
- Communication deficits may often explain aggression (can’t communicate distress & discomfort)
- Can have full range of mental disorders, but often difficult to identify
- Comorbid mental disorders common (3-4 x greater prevalence)
- ID may influence how anxiety, depression, etc. manifests
ID: Culture, Age, and Gender
- Must consider culture when assessing intellectual functioning
- Must consider developmental factors when evaluating adaptive skills
- Slightly more common in males (1.6:1 mild, 1.2:1 severe)
Prevalence and Course of ID
- About 1% gen population
- More severe levels associated with genetic syndromes
- Severe level often has acute onset
- Lifelong impairment is typical, but supports can improve ADLs and QoL
Developmental vs Acquired ID
- Dx not dependent on specific etiology
- Dx depends on developmental level: during childhood diagnosed with ID but during adulthood diagnosed with neurocognitive d/o (if already have ID, then acquire head injury you can diagnose both)
ID: Differential Diagnosis
- Major & Mild Neurocognitive Disorder
- Specific LD
- Communication Disorders
- Autism Spectrum Disorder
- Deafness
Ethical Considerations with Diagnosis of ID
- School referral-to-placement decisions based on state interpretations of IDEA
- Diagnosis affects eligibility for services
- Impacts prognosis and life course
Etiology of ID
- 30% unknown
- 40% genetic disorder
- 10% metabolic disorders
- 10% teratogens
- 10% perinatal problems or injury
Hereditary and Chromosomal Disorders
Tay Sach’s Disease (errors in metabolism), Phenylketonuria (errors in metabolism), Tuberous Sclerosis (single-gene), Neurofibromatosis (single-gene), Fragile X syndrome (chromosomal aberrations), Down’s syndrome (trisomy 21), Cri-du-Chat (chromosomal deletion), Prader-Willi Syndrome (chromosomal deletion)
ID: Prenatal Events
- Nutritional deficiencies
- Congenital infections
- Exposure to toxins (e.g., FAS)
- Neural tube defects
- Iodine deficiency disease
- Rhesus incompatibility
ID: Perinatal Events
- Hypoxia
- Hypoglycemia
- Cerebral hemorrhage
- Gross trauma
- Fetal malnutrition
- Prematurity
- Low birth weight
ID: Postnatal Events
- Infections/illness: encephalitis/meningitis
- Trauma/accidents: TBI, near drowning
- Malnutrition
- Toxins & poisons: lead poisoning, mercury exposure
- Environmental deprivation
- Child abuse
Dual-Diagnosis
ID + another mental disorder
- full range of psychiatric disorders can emerge
- rates much higher (30-50%)
- lower functioning = higher rates
- difficult to assess
Einfeld article
Collectively, these studies demonstrate rates of comorbidity for children and adolescents between 30 and 50% with a relative risk of mental disorder associated with intellectual disability ranging from 2.8–4.5.
Stereotypy
Repetitive motor movements that are nonfunctional (e.g., body rocking, hand flapping)
Self-injurious behavior
Repetitive behaviors which may result in self-inflicted bodily injury (e.g., head banging, self-biting, face slapping)
Stereotypic Movement Disorder DSM-5 Criteria
- Repetitive, apparently purposeless motor behavior
- Interferes with social, academic, or other activities that may result in self-injury
- Onset in early developmental period
- Not attributable to substance, neuro condition, or another disorder
Specify if: with or without self-injurious behavior, associated with a known medical or genetic condition, neurodevelopmental disorder, or environmental factor
Stereotypic Movement Disorder: Epidemiology/Prevalence/Course
- Most commonly seen in ID (4-16%)
- SIB more common with certain GMCs
- Sometimes seen with severe sensory deficits
- More common in institutional settings
- Gender difference (head banging more common in males, self-biting more common in females)
- 3-4% children/adol in community
- Onset typically by age 3; can persist for years but typography may change
- Note: not Tic Disorders, ASD, OCD, etc.
History of ASDs
- 1943 Kanner (U.S.)
- —- 11 cases of “early infantile autism;” 3 problem areas
- —- 3 problem areas: social isolation, peculiar language, insistence on sameness
- 1944 Asperger (Austria)
- —- 4 cases of “autistic psychopathy”
- —- Impairments in pragmatic language, social interaction, circumscribed interests, clumsiness
- —- Unknown until 1981, when described as Asperger Syndrome
- 1980 DSM-III: Infantile autism
- 1994 DSM-IV: Asperger Syndrome added
- 2013 DSM-5: Autism Spectrum Disorder
ASD Controversies
- Is Asperger’s a separate disorder/valid diagnostic category?
- Are actual rates of ASD increasing or is it just rate of diagnosis increasing?
- Do the DSM-5 criteria under-identify children?
DSM-IV Pervasive Developmental Disorders
- Autistic Disorder
- Asperger’s Disorder
- Rett’s disorder (genetic disorder taken out in DSM-5)
- Childhood disintegrative disorder
- Pervasive Developmental Disorder, NOS
- Above are now lumped under “Autism Spectrum Disorder” in DSM-5
Autism Clinical Presentation
- Chief complaint: no language and lack of social responsiveness
- Concerns that child is deaf, neurologically impaired, or ID
- Often concerns have been present 2-3 years
