What is Autism?
Autism and autism spectrum disorder (ASD) are both general terms for a group of complex disorders of brain development. These disorders are characterized, in varying degrees, by difficulties in social interaction, verbal and nonverbal communication and repetitive behaviors. They include autistic disorder (sometimes referred to as “classic autism”), Rett syndrome, childhood disintegrative disorder, pervasive developmental disorder-not otherwise specified (PDD-NOS) and Asperger’s syndrome. ASD can be associated with intellectual disability, difficulties in motor coordination and attention and physical health issues such as sleep and gastrointestinal disturbances. Some persons with ASD excel in visual skills, music, math and art.
Autism has its roots in early brain development. However, the most obvious signs of autism and symptoms of autism tend to emerge between 12 and 18 months of age. Some infants and toddlers begin develop normally until the second year of life, when they lose skills and develop autism – a pattern called “regression.” Autism Speaks continues to fund research on effective methods for earlier diagnosis, as early intervention with proven behavioral therapies can improve outcomes. Increasing autism awareness is a key aspect of this work and one in which our families and volunteers play an invaluable role. Learn more …
How Common is Autism?
Autism statistics from the U.S. Centers for Disease Control and Prevention (CDC) identify around 1 in 68 American children as on the autism spectrum–a ten-fold increase in prevalence over the last 40 years. Careful research shows that this increase is only partly explained by improved diagnosis and awareness. Studies also show that autism is four to five times more common among boys than girls. An estimated 1 out of 42 boys and 1 in 189 girls are diagnosed with autism in the United States.
ASD is estimated to affect more than 2 million individuals in the U.S. and tens of millions worldwide. Moreover, government autism statistics suggest that prevalence rates have increased 10 to 17 percent annually in recent years. There is no established explanation for this continuing increase, although improved diagnosis and environmental influences are two reasons often considered.
What Causes Autism?
Not long ago, the answer to this question would have been “we have no idea.” Research is now delivering the answers. First and foremost, we now know that there is no one cause of autism just as there is no one type of autism. Over the last five years, scientists have identified a number of rare gene changes, or mutations, associated with autism. Research has identified more than a hundred autism risk genes. In around 15 percent of cases, a specific genetic cause of a person’s autism can be identified. However, most cases involve a complex and variable combination of genetic risk and environmental factors that influence early brain development.
In other words, in the presence of a genetic predisposition to autism, a number of nongenetic, or environmental, influence further increase a child’s risk. The clearest evidence of these environmental risk factors involves events before and during birth. They include advanced parental age at time of conception (both mom and dad), maternal illness during pregnancy, extreme prematurity and very low birth weight and certain difficulties during birth, particularly those involving periods of oxygen deprivation to the baby’s brain. Mothers exposed to high levels of pesticides and air pollution may also be at higher risk of having a child with ASD. It is important to keep in mind that these factors, by themselves, do not cause autism. Rather, in combination with genetic risk factors, they appear to modestly increase risk.
A small but growing body of research suggests that autism risk is less among children whose mothers took prenatal vitamins (containing folic acid) in the months before and after conception.
Increasingly, researchers are looking at the role of the immune system in autism. Autism Speaks is working to increase awareness and investigation of these and other issues, where further research has the potential to improve the lives of those who struggle with autism. Learn more …
What Does it Mean to Be “On the Spectrum”?
Each individual with autism is unique. Many of those on the autism spectrum have exceptional abilities in visual skills, music and academic skills. About 40 percent have intellectual disability (IQ less than 70), and many have normal to above average intelligence. Indeed, many persons on the spectrum take deserved pride in their distinctive abilities and “atypical” ways of viewing the world. Others with autism have significant disability and are unable to live independently. About 25 percent of individuals with ASD are nonverbal but can learn to communicate using other means. Our goal is to improve the lives of all those on the autism spectrum. For some, this means the development and delivery of more effective treatments that can address significant challenges in communication and physical health. For others, it means increasing acceptance, respect and support.
How Did My Child Develop Autism?
Research suggests that the development of autism is rooted in very early brain development. However, in most cases, no one cause can be identified. Research has identified several genes that can cause autism in and of themselves. These account for about 15 percent of cases of autism spectrum disorders. Research has identified more than 100 genes or gene changes (mutations) that increase the risk that a child will develop autism. In most cases, genetics alone can’t distinguish why one person has autism and another does not. Gene-environment interactions appear to be at play. When scientists use the term “environment,” they are referring to a wide range of non-genetic factors. Those most associated with increased autism risk include advanced parental age at time of conception and prematurity with very low birth weight. Other possible environmental risk factors include maternal diabetes or infection during pregnancy and certain birth complications, particularly those that may involve oxygen deprivation to a baby’s brain.
What Should I Do if I Suspect Something is Wrong with My Child?
Don’t wait. Talk to your doctor or contact us about getting your child screened for autism. Research has consistently shown that early diagnosis and intervention offer the best chance for improving function and maximizing a child’s progress and outcomes.
How Do I Get My Child the Help He or She Needs?
It’s important to make sure your child has a knowledgeable and reputable health-care team. This means finding doctors, therapists, psychologists and teachers who understand and have experience with autism and can respond to his shifting needs appropriately.