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Autism numbers are holding steady as world researchers study the cause

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The numbers appear to be holding steady in the United States regarding the prevalence of Autism Spectrum Disorder (ASD). The Centers for Disease Control and Prevention (CDC) conducted another survey since the last one in 2014—this time studying 8-year-olds in 11 states—and has concluded that the statistics have not changed, which means that one in 68 children will be diagnosed this year as being autistic.

ASD is a developmental disorder that can cause significant social, communication and behavior challenges. People with ASD don’t typically look any different from the next person, but these individuals may communicate, interact, behave and learn in ways that are strikingly different than most other persons. The latest research has identified several conditions that used to be diagnosed separately, including autistic disorder, pervasive developmental disorder (not otherwise specified), and Asperger Syndrome. All of these conditions are generally categorized today as ASD.

Diminished social skills

ASD should not be confused with Down Syndrome, once referred to as mental retardation. Most autistic persons rarely display the common physical characteristics of Down Syndrome (e.g. a “flat” face with a small nose, upward slant to the eyes, abnormally shaped ears), nor do they suffer from a specific thyroid condition (i.e. hypothyroidism or “slowing” of the thyroid gland). ASD is primarily associated with diminished social skills, with the signs beginning in early childhood and typically lasting a lifetime. Children, youth and adults with ASD may not point at an object to show interest (i.e. an airplane flying over), or they may not look at an object when another person points at it. Autistic persons usually have trouble with empathy or understanding other people’s feelings (or talking about their own feelings). Experts say a baby with ASD may not want to be cuddled—or even touched—and may appear to be unaware when people are talking to him/her. Persons with ASD are not specifically introverted—they may be very interested in other people—but do not posses the ability for extended conversation or dialogue. If anything, these individuals will likely echo or repeat words or phrases said to them, or repeat words or phrases in place of normal language.

Diagnosis more likely in boys

Race or ethnicity  have no particular bearing on an ASD diagnosis. Neither does socioeconomic status. The CDC reports that boys, on average, experience ASD about 4.5 times (1 in every 42 births) more likely than girls (1 in 189). Scientists have been studying ASD for decades, and appear to be just as baffled as they were 30 years ago particularly when observing the range of the disease which may extend from mild disabilities such as speech and language impairments, to serious developmental disorders such a pronounced intellectual disability or cerebral palsy. ASD, according to CDC findings, tends to occur more in people who may have certain genetic or chromosomal conditions. About 10 percent of children with ASD are, in fact, identified with Down Syndrome, Fragile X Syndrome (physical features may include large ears or a long face, flat feet or a high-arched palate) and tuberous sclerosis (non-cancerous tumors or lesions that commonly grow in the brain or other internal organs).

There are certain risk factors associated with persons who may have ASD. Studies have demonstrated that among identical twins, if one child has ASD, then the other will be affected about 36 to 95 percent of the time. In non-identical twins, if one child has ASD then the other is affected anywhere from zero to 31 percent of the time. The CDC reported this year that parents who have one child with ASD have about a two- to 18-percent chance of having a second child who is also affected. Despite the these dire research findings, further studies conducted by the CDC found that almost half (about 44 percent) of children identified with ASD have average to above-average intellectual ability.

Risk higher among older parents

Sometimes age can play a role in the physical and intellectual development of a child. Further research into the gestational causes of ASD indicated that children born to older parents may be at a higher risk of having ASD, and a small percentage of children who are born prematurely or with low birth weight could be at risk of the disorder.

For at least two decades, various theories of the causes of ASD have ranged from a common fever to, of late, administering the measles vaccine. One theory that remains more plausible within the community of medical research practitioners is that the brains of persons with ASD are, somehow, structurally normal but dysregulated, meaning that symptoms of the disorder might be reversible. This theory was first published in the journal PsychCentral and suggests that autism is a developmental disorder caused by impaired regulation of a bundle of neurons in the brain stem that processes sensory signals from all areas of the body.

Among the social issues related to ASD according to researchers are:

— A child does not respond to name by 12 months of age;

— Avoids eye contact;

— Does not share interests with others;

— Only interacts to achieve a desired goal;

— Does not understand personal space boundaries;

— Is not comforted by others during distress;

— Has trouble understanding other people’s feelings (empathy) or talking about his/her own feelings.

Symptoms of Asperger Syndrome

Some of the symptoms of Asperger Syndrome—such as a need for routine and resistance to change—are believed by some scientists to be linked to levels of the stress hormone cortisol. People normally have a high level of this hormone shortly after waking, with levels gradually decreasing throughout the day. Some researchers believe  that this surge makes the brain alert, thereby preparing the body for the day and helping the person to be aware of changes happening around them. These researchers have determined that children with Asperger Syndrome do not experience this surge.

Other theories about the cause of ASD stem from decades of anecdotal observations that some autistic children seem to improve when they have a fever, only to regress when the fever ebbs. In 2007, the journal Pediatrics took a more rigorous look at fever and autism, observing autistic children during and after fever episodes and comparing their behavior with autistic children who didn’t have fevers. The study revealed that autistic children can and will experience behavior changes during fever.

The scientists speak on ASD

There are plenty of theories regarding the cause of ASD. For about five years, researchers at the Institute for Brain Disorders and Neural Regeneration at Einstein College in New York have contended that scientific evidence points directly to the “locus coeruleus—noradrenergic (LC-NA)” system which, according to ASD experts, is the only brain system involved in both “producing fever and controlling behavior.” A co-author of the study, Dr. Dominick P. Purpura, explained that the locus coeruleus has widespread connections to brain regions that process sensory information. It secretes most of the brain’s noradrenaline, which is a neurotransmitter that plays a key role in arousal mechanism such as the common “fight or flight” response. It is also involved in a variety of complex behaviors, such as attentional focusing (how the brain concentrates attention on environmental cues relevant to the task at hand, or to switch attention from one task to another). Poor attentional focusing, according to Purpura, is a defining characteristic of ASD.

Purpura looked a little further and hypothesized that in autism, the LC-NA system is dysregulated by the interplay of environment, genetic and epigenetic factors (chemical substances both within and outside the genome that regulate the expression of genes). He suggested that stress may play a central role in dysregulation of the LC-NA system, especially in the latter stages of prenatal development, when the fetal brain is particularly  vulnerable. Purpura’s findings indicate that, in autistic children, fever may stimulate the LC-NA system, thereby temporarily restoring its normal regulatory function.

Research, medicine are reasons for hope

“This could not happen, if autism was caused by a lesion or some structural abnormality of the brain,” Purpura said. “This gives us hope that we will eventually be able to do something for people with autism.”

Neither Purpura nor his colleagues advocate fever therapy (fever induced by artificial means) which experts explain would be an overly broad—and perhaps dangerous—remedy. Instead, they say the future of ASD treatment probably lies in drugs that selectively target certain types of noradrenergic brain receptors or, more likely, in epigenetic therapies targeting genes of the LC-NA system. Purpura and his fellow researchers have looked into the causes of Asperger Syndrome and, while it is still far too early to make a definite conclusion into the causes of the neurological disease, they believe that cortisol, the body’s stress hormone, could be a key component to understanding and offer clues about treatment.

“Cortisol is one of a family of stress hormones that acts like a ‘red alert’ that is triggered by stressful situation allowing a person to react quickly to changes around them,” said Dr. Mark Brosnan, who also participated in the research. “In most people, there is a two-fold increase in levels of this hormone within 30 minutes of waking up. These levels gradually decline during the day as part of the internal body clock. Our study found that children with Asperger Syndrome didn’t have this peak, although levels of the hormone still decreased during the day as normal.” Brosnan said that scientific research into the causes of Asperger Syndrome is, to coin a phrase, still in its “infancy,” but the difference in stress hormone levels “… could really be significant in explaining why children with ASD are less able to react and cope with unexpected change.”

Cost to economy rises yearly

Research has demonstrated that a diagnosis of ASD at age 2 can be reliable, valid and stable. Even though ASD can be diagnosed at this early age, most children are not diagnosed until after age 4. Studies have shown that parents of children with ASD may notice a developmental problem before their child’s first birthday. Also, concerns about vision and hearing were more often reported in the first year, and differences in social, communication and fine motor skills were evident from 6 months of age.

There are considerable economic costs nationally for children with ASD. The National Center for Biotechnology Information gathered statistics for 2012 and reported that the total costs per year for American children with ASD was $60.9 billion—and likely higher today—because of a variety of direct and indirect costs, among them medical care, special education and lost parental productivity. Children and adolescents with ASD had average medical expenditures that exceeded those without ASD by $4,000 to $6,300 per year. On average, medical expenditures for children and teens with ASD were reportedly 4.1- to 6.2-percent higher than for those young people without the disorder.

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