Most common of autism spectrum disorders.
ASD affects the ability to interact socially, and communicate with others.
ASD diagnosed in 1 in 36 children in the US.
Autism spectrum disorder diagnosis is increasing with an estimated prevalence of 1.4% among eight-year-old children in the US.(ElsabbaghM et al).
The estimated prevalence for children, aged 8, is up to 2.7% in 2020.
Higher prevalence of ASD is due to improved ascertainment, greater access to services, earlier behavioral intervention and education with individualized programs designed for children with ASD.
The definition of autism now includes a broader spectrum of manifestations, which partly explain the increase in prevalence.
There is a better understanding of the ways autism manifests in people, and the surge in autism is due to the advances in the ability to understand and characterize the condition.
Autism spectrum disorder is associated with impaired social communication and social interaction as well as restricted, repetitive patterns of behavior, interest, or activities.
Autism is associated with different thinking patterns and brain processing functions in the area of social thinking and actions may compromise their ability to understand themselves and social connections to others.
Autism spectrum disorder and autism are a group of complex disorders of brain development, characterized by difficulties in social interaction, verbal and nonverbal communication and repetitive behaviors.
There is an estimated genetic heritability of greater than 80% and environmental influence in 14 to 22% for the risk of ASD.
Approximately 100 genes have been identified that are associated with significant risk, whereas a larger number, perhaps, thousands, of common variants are associated with smaller risk but, in combination, account for the majority of cases.
Genetic risk factors for ASD overlap with developmental and psychiatric disorders.
A variety of genetic and environmental factors have been associated with ASD, but none are absolutely specific for its development.
Estrogen mitigates the effects of ASD risk gene disruption and helps explain the sex difference in prevalence.
Studies have found that individuals on the autistic spectrum self-report lower levels of empathic concern, show less or absent comforting responses toward someone who is suffering, and report equal or higher levels of personal distress compared to controls.
Many patients with autism spectrum disorder struggle to acquire adaptive behavioral skills, including socialization, communication, and daily living skills.
Intellectual disability, language disorder, and medical and psychiatric conditions, including epilepsy, sleep, problems, anxiety, and depression are common.
Anxiety, depressive disorders, suicidality are all more common in patients with autism and greatly contribute to reduced quality of life and increased mortality.
People with ASD have an increased risk of epilepsy, intellectual disability, motor difficulties, difficulties in coordinating movements, difficulties in maintaining their posture, constipation, sleep difficulties, compared to those without ASD.
About 75% diagnosed autistics are mentally handicapped in some general way and the other 25% diagnosed with Asperger’s Syndrome show average to good cognitive functioning.
ASD manifests in pragmatic or social norms, associated with communication, such as speaking, with inappropriate volume, interacting at appropriate physical distance, and detecting and adapting communication in response to gestures and facial expression.
Children suffering from varying degrees of autism struggle in social situations, and that self-awareness is a main problem for people with ASD.
There may be rigidity, manifested by requiring others to speak, or behave in specific ways, or needing to adhere to prescribe schedules or activities.
Savant skills that most commonly manifest as memory, art, music, mental arithmetic, and calendar calculation are more common in people with ASD.
Savant skills may occur, and as many as 29% of affected individuals with ASD.
ASD complexity and heterogeneity relate to both developmental factors, such as age and intelligence, environmental factors, such as availability of support, including educational services, speech, and language, and behavioral interventions.
Daily living skills, including toileting skills, contribute to an individual’s prognosis and the level of independent functioning.
Children with autism spectrum disorder may have difficulty with toilet training, which affects whether they will achieve daytime dryness.
Autism spectrum disorder affects approximately 1 in 68 children in the US.
Autism prevalence rates of 2 and 2.47% in school aged children have been estimated international health surveys.
In a study of children, with ASD, in with younger siblings were followed, prospectively from birth, 19% of these younger siblings were diagnosed with ASD by the age of 36 months.
Autism spectrum disorder has increased in prevalence.
Autism spectrum disorder affects an estimated six per 1000 children worldwide.
Autism spectrum disorder is heritable and sibling recurrence rate is approximately 25%, suggesting environmental factors interact with genetic risks over a critical period of neurodevelopment to produce the final phenotype.
No single identifiable cause.
Autism spectrum disorder (ASD) is characterized by cognitive inflexibility and poor understanding of social systems, which originates in defects in the pre-frontal cortex as well as the striatal circuits.
The defects in the striatum seem to specifically contribute to the motor, social and communication impairments seen in ASD patients.
A neurobiological disorder that profoundly affects the functioning of the brain.
Associated with abnormalities in several regions of the brain including the cerebellum, amygdala, hippocampus, septum and mamillary bodies with neurons in these regions appear smaller than normal and have stunted nerve fibers which may interfere with nerve signaling.
May result from disruption of normal brain development early in fetal development.
Some studies suggest abnormalities of serotonin or other signaling molecules in brain.
Twin and family studies suggest that genetic factors play a causal role.
May involve as many as 5-15 genes.
Prenatal exposure to valproic acid, thalidomide and alcohol has been associated with an increased risk.
The use of prenatal folic acid supplements around the time of conception is associated with lower risk of autism spectrum disorders in children (Suren P et al).
Occurs more frequently in children with other medical conditions including fragile X-syndrome, tuberous sclerosis, phenylketonuria and congenital rubella syndrome.
Complex developmental disability that typically appears during the first three years of life.
Affects the functioning of the brain.
As many as 50% of children with autism spectrum disorder exhibit behavior problems including self injury, aggression, noncompliance, and tantrums.
Behavioral disorders in ASD interfere with child’s ability to benefit from educational services, perform daily acts of living and may increase social isolation.
The presenting symptoms of ASD depend on the age, language levels, cognitive abilities, and sex.
In the first two years of life, common features include: poor acquisition of or declines in language, skills and communicative gestures, or failure to learn to adapt these skills.
It is also characterized by diminished responsiveness in social interactions and the presence of repetitive behaviors, such as no response to name when called, hand flapping, and lining up toys in a particular way.
Autism is characterized by decreased spontaneous visual attention to social stimuli.
3rd most common developmental disability.
It is estimated to occur in as many as 1 in 500 individuals.
4 times more prevalent in boys than girls.
Females likely are underdiagnosed or overlooked by clinicians because of stereotypical gendered expectations and interpretation of behaviors.
Girls and women are more likely or better able to minimize ASD symptoms including social communication.
More common than Down Syndrome.
There are higher rates of ASD reported among trans gender and gender, diverse individuals.
Children with ASD, who are Black tend to present at older ages than those who are White and more often present with intellectual disability, suggesting racial disparities in access to care.
A spectrum disorder that may range from mild to severe.
Difficulty in communicating with others and relating to the outside world.
Have resistance to changes in routines.
May experience sensory problems in the 5 senses of sight, touch, hearing, smell and taste.
Girls with autism spectrum disorder are less likely to have obvious repetitive behaviors, such as hand flapping, which is usually the first clue parents notice and typically leads to the diagnosis at age 3 or four years.
Girls with the autism spectrum disorder generally have less severe symptoms than boys.
A neurobiological disorder affecting the functioning of the brain with abnormalities in the cerebellum, amygdala, hippocampus, septum and mamillary bodies with smaller than normal neurons and have stunted nerve fibers: suggesting disruption of normal brain development early in fetal development. noted to be concurrent
When gestational diabetes diagnosed by 26 weeks associated with an increased risk of autism spectrum disorders.
Signs of autism often preceded by or noted to be concurrent with abnormal head and brain overgrowth (Courchesne E et al).
Increased neuron number in the prefrontal cortex in male children and adolescents with autism has been noted by Courchesne E et al).
Abnormal neurobiological development begins at 9-18 months of age.
Macrocephaly occurs in 20% of patients and is usually due to megalencephaly in childhood.
Brain enlargement is rarely present at birth, but develops during early childhood during the first 18 months of life.
Mean total brain, lobar, white and gray matter volumes, cortex volumes, are significantly increased by age 2 to 3 in children with autism.
Excessive head and brain growth occur prior to clinical manifestations in most instances, suggesting that excessive growth of the brain may play a role in the neuropathology of the process.
Brain overgrowth in males with excess number of neurons in the prefrontal cortex and these cortical neurons are generated prenatally.
Prenatal cortical neuron proliferation, reduced apoptosis or both occur in autisitic children.
Serotonin and other signaling molecule abnormalities in brain are suggested.
A complex genetic disorder and may involve as many as 5-15 genes and may involve environmental factors.
Prenatal exposure to valproic acid, thalidomide and alcohol has been associated with increased risk.
Patients with autism spectrum disorder have increases in pro-inflammatory cytokines have been found both in the CSF of patients and in postmortem brain tissue from deceased patients.
No scientific link between vaccines and autism.
Valproate use is associated with a significant increase risk of autism spectrum disorder and childhood autism (Christensen J et al).
One of five conditions referred to as autism spectrum disorders or pervasive developmental disorders: Autism, Asperger’s syndrome, Childhood disintegrtive disorder, Pervasive development disorder not otherwise specified, Rett syndrome.
May be sensitive to sensory stimulation, such as light, sound and touch.
Majority also have mental retardation, however some children with autism have normal to high intelligence.
Characterized by impaired social interaction, problems with verbal and nonverbal communication, repetitive activities, and limited interests.
Incidence 3 to 6 per 1000 children.
A genetic predisposition is present with one autistic child, the risk of having a second child with the process is approximately 5%.
In some cases parents and other relatives of individuals with autism have emotional, social and communicative difficulties or engage in in repetitive behaviors.
Behavioral problems range from mild to profound.
May begin in early infancy with unresponsiveness to people and intense focus on one item to the exclusion of others.
Children may develop normally and subsequently withdraw and become indifferent to social situations.
Children often avoid eye contact with others and fail to respond when their name is called.
Patients lack empathy.
Adults with autistic spectrum disorders have an increased inability to recognize and articulate emotional arousal in oneself or others (alexithymia).
The combination of autism spectrum of reduced empathic concern and increased personal distress may lead to the overall reduction of empathy.
Autistic individuals have impaired understanding of complex social emotions or in considering others’ viewpoints.
Alexithymia overlaps with autism spectrum disorders (ASD).
Individuals lack the ability to take social cues from others, not appreciating voice or facial expressions.
Frequently patients have repetitive rocking movement and twirling.
May be involved with self-abusive behavior such as biting or head banging and aggression.
May speak later than other children, and may lose previous ability to say words or sentences.
May speak with an abnormal tone or rhythm with singsong voice or robot-like speech.
Can not start a conversation or keep one going.
May refer to themelves by name instead of I or me.
Children do not interact well with other children, and do not demonstrate interest in other individuals.
Patients have a reduced sensitivity to pain, and increased sensitivity to noise, touch or other sensory stimulation.
The estimated prevalence of ASD is higher individuals with special health needs, with an estimated 19% of people with visual impairment, and 9% with hearing impairment, 18% of people with intellectual disability, 16% of people with Down syndrome and 30% of people with fragile X syndrome have ASD.
Children resist hugging and cuddling.
Higher risk for the presence of fragile X syndrome, tuberous sclerosis, epilepsy, Tourette syndrome, congenital rubella syndrome and phenylketonuria, learning disabilities, and attention deficit disorder.
Seizures occur in 20-30% of children by the time they reach adulthood.
Compared with spontaneous conception IVF is not associated with autistic disorders but is associated with a small increase in the risk of mental retard station (Sandin S et al).
Too Much Folic Acid in Pregnancy Tied to raised autism risk
Pregnant women are encouraged to get plenty of folic acid in their diet or through vitamin supplements, to protect their babies against birth defects of the brain and spinal cord.
Excessive amounts of folate and vitamin B12 in a mother’s body might increase a baby’s risk of developing an autism spectrum disorder (Fallin D).
Mothers who had very high blood levels of folate at delivery were twice as likely to have a child with autism compared to mothers with normal folate levels.
Mothers with excessive B12 levels were three times as likely to have a child with autism.
The risk was greatest among mothers who had excess levels of both folate and B12 — their risk was over 17 times that of a mother with normal levels of both nutrients.
Folate is found naturally in fruits and vegetables, while the synthetic version, folic acid, is used to fortify cereals and breads in the United States, and in vitamin supplements.
Women who took folate and B12 supplements three to five times a week are less likely overall to have a child with autism, particularly when they’re taken during the first and second trimesters.
Studies have indicated that folate and vitamin B12 might protect a developing fetus against future autism.
Around 70% of people with autism also have gastrointestinal problems, and autism is often diagnosed at the time that the gut flora becomes established, indicating that there may be a connection between autism and gut flora.
Data from almost 1,400 mother-child pairs in the Boston Birth Cohort, a predominantly low-income minority population, included a check of the mothers’ blood folate levels within three days of delivery: one in 10 of the women had what is considered an excess amount of folate, while 6 percent had an excess amount of vitamin B12.
Women who had extremely high, much higher than the recommended amount, of folate or vitamin B12 were more likely to have children who later had a diagnosis of autism.
In children and adolescents with autism spectrum disorders treatment with fluoxetine compared with placebo results in significantly lower scores for obsessive compulsive behavior at 16 weeks.
There is a lack of objective, quantitative bio markers to improve diagnostic tools for autism.
The eye tracking test can accurately classify autism versus non-autism in children with a 71% sensitivity and an 80.7% specificity with a positive predictive value of 76.2.