Autism Spectrum Disorders

February 22, 2010

Debates regarding recent changes to the guidelines for diagnosis of Asperger syndrome, often considered a high-functioning form of autism which inhibits the ability to interact socially and causes repetitive behaviors, are ongoing. According to the Centers for Disease Control and Prevention (CDC), one in 110 children have an Autism Spectrum Disorder (ASD). Time Magazine reports that researchers at the University of Leicester, working with the NHS Information Center found that roughly 1 in 100 adults exhibit an ASD. Though the exact cause for these conditions is not known, the rate at which they are occurring is increasing. The Centers for Disease Control and Prevention indicate that autism and related disorders are more common than previously thought, though it is unclear if this increase is due to an improved ability to diagnose.

A developmental disorder that appears in the first three years of a child’s life, autism affects the brain’s development of social and communication skills. One in every 110 8-year-old children, and one of every 70 boys, in the United States has been diagnosed with autism. The CDC indicates that; per the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision and International Classification of Diseases, Tenth Revision; “criteria have identified ASD rates ranging from 2.0 to 12.0 per 1,000 children” worldwide. Individuals with autism may repeat body movements, have difficulty communicating, and avoid social interaction, including physical contact. Findings from a study of mice with Fragile X Syndrome, a condition that is often linked to autism, indicate that delayed development in the sensory cortex of the brain may be the cause of autistic individuals’ aversion to touch. Dr. Gina Gómez de la Cuesta, from the National Autistic Society, notes that “Autism is common in people with fragile X syndrome, however there are many other causes of autism, most of which are not yet fully understood.”

Efforts to identify causes, treatments, and prevention measures for the disorder are ongoing. Some advocates maintain that diets removing gluten (found in wheat, barley, and rye) and casein (found in dairy) alleviate some of the symptoms of autism, however there has not been any scientific documentation of the success of these restricted diets. A now-discredited study published in the Lancet in 1998 indicated a link between autism and the measles, mumps, and rubella vaccine frequently administered in early childhood. According to experts, the frequency with which autism symptoms become more apparent at two years of age when receiving these vaccinations, is coincidental, as childhood vaccines do not cause the disorder.

New research indicates that babies born prior to the 26th week of pregnancy, are at a higher risk of developing autism. A recent study showed eight percent of 219 children born in this timeframe, met the criteria for an ASD at the age of 11. A comparison group of 153 children born full-term were also included in the study, none of whom exhibited signs of autism or other ASDs. The age of both parents has also been linked to a child’s likelihood of developing an ASD. Data collected from 4.9 million births in the 1990s in California indicated that compared with women in their mid- to late-20s, women giving birth after 40 had a 50 percent increase in the risk of having an autistic child. The father’s age was also found to impact the likelihood of having a child with autism, but only in the case of men over 40 having children with women under 30.

Recent research indicates a correlation between a deficiency in oxytocin, a hormone that makes women more maternal and men less shy, and autism or Asperger syndrome. In a study of 13 adults with high-functioning autism or Asperger syndrome, use of a nasal spray containing oxytocin was found to improve scores on a test involving recognition of faces. This type of medical intervention could provide an additional treatment option for children and adults with ASDs who are currently involved in behavioral interventions. Though often expensive, structured behavioral interventions and early intervention programs have been found to improve the language skills of children with ASDs, sometimes increasing the IQ of children as many as 18 points. Direct medical and non-medical costs for an individual with an extreme case can total as much as $72,000 per year. Medications, clinical visits, and occupational and speech therapy, as well as special education, camps, and child care are just some of the expenditures of parents of children with autism. As individuals with autism grow into adulthood, these costs continue, as caregivers and specialized programs may be needed.

There is still no known direct cause for autism and other ASDs. These conditions can put an emotional and economic strain on families, and can lead many parents to blame themselves for their children’s condition. With improved diagnostic tools and earlier diagnoses, children with autism can receive early intervention treatments and education to improve their outcomes.

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