CHAPEL HILL, NC ( Ivanhoe Newswire) - New statistics show autism affects one in 88 children in the U.S. Catching it early is key in treating the problem. Now, special imaging may help detect autism sooner than ever before.
Gracie goes everywhere big brother Seth goes, but her parents hope Gracie doesn't follow in Seth's footsteps when it comes to one thing, Seth has autism. Siblings have a one in five chance of developing autism.
"I was concerned about it," Tony Whitaker, Gracie and Seth's father, told Ivanhoe.
They decided to enroll Gracie in a one-of-a-kind study. UNC researchers used a special kind of MRI imaging called, diffusion tensor imaging, to look at 15 brain connections of babies who had a sibling with autism. They found significant differences in 12 of the 15 connections in those who developed autism.
"What we find is the children who went on to have autism, we can see differences as early as six months, and that over time their brains changed less," Jason Wolff, Ph.D., a postdoctoral fellow at the University of North Carolina School of Medicine, explained.
Right now, it's almost impossible to diagnose autism at six months. These scans could offer a way to catch it much earlier.
"This is really before we can pick up any differences behaviorally," Dr. Wolff said. "If we could go earlier and earlier in our interventions, we could prevent autism from fully manifesting."
Gracie seems to be developing normally. A relief to her parents who say their little girl is a big part of helping Seth deal with his disorder.
"We can't imagine where Seth would be if it wasn't for Gracie," Sally Whitaker, Gracie and Seth's mother, said.
Doctor Wolff said the imaging could one day be used with behavioral exams, which are the current standard, to better diagnose autism. The hope is to catch it before signs start to show. A recent study published in pediatrics found when children as young as 18 months underwent therapy for autism, their IQ improved by 14 points compared to other kids with autism.
RESEARCH SUMMARY
BACKGROUND: Autism is a general term for a group of complex disorders of brain development. These disorders are characterized by difficulties in social interaction, verbal and nonverbal communication, and repetitive behaviors. Autism can be associated with intellectual disability, difficulties in motor coordination, and attention and physical health issues such as sleep and gastrointestinal disturbances. Some with certain types of autism excel in visual skills, music, math and art. According to the U.S. Centers for Disease Control and Prevention, about 1 in 88 children in the United States has autism. This is a 10-fold increase in prevalence in 40 years. Studies also show that autism is three- to four-times more common in boys. About 1 out of 54 boys and about 1 out of 252 girls are diagnosed with autism in the United States. This is more children than are affected by diabetes, AIDS, cancer, cerebral palsy, cystic fibrosis, muscular dystrophy or Downs syndrome combined. Government statistics suggest that prevalence rates have increased 10 to 17 percent annually in recent years.
(SOURCE: Autismspeaks.org)
DIAGNOSING AUTISM: Research now suggests that children as young as 1 year of age can show signs of autism. It's important to diagnose autism as soon as possible because early intervention may be a child's best hope. Some red flags that may suggest a child should be screened include:
- No big smiles or joyful expressions by 6 months or thereafter
- No back-and-forth sharing of sounds, smiles, or other facial expressions by 9 months or thereafter
- No babbling by 12 months
- No back-and-forth gestures such as pointing, showing, reaching or waving by 12 months
- No words by 16 months
- No two-word meaningful phrases by 24 months
- Any loss of speech or babbling or social skills at any age
(SOURCE: Autismspeaks.org)
IMAGING STUDY: A new study, led by researchers from the University of North Carolina at Chapel Hill, found significant differences in brain development starting at 6 months of age in high-risk infants who later develop autism. The study suggests that autism does not appear suddenly in young children, but instead, develops over time during infancy. Researchers studied 92 infants who had older siblings with autism and were therefore considered to be at high-risk themselves. All participants had diffusion tensor imaging -- which is a type of MRI -- at 6 months and behavioral assessments at 24 months. Most also had additional brain imaging scans at either or both 12 and 24 months. At 24 months, 30 percent of the infants met the criteria for autism spectrum disorders while 70 percent did not. The two groups differed in white matter fiber tract development -- pathways that connect brain regions -- as measured by fractional anisotropy. This measures white matter organization and development based on the movement of water molecules through brain tissue. The researchers studied 15 separate fiber tracts. They found significant differences in FA trajectories in 12 out of the 15 tracts between infants who did develop autism versus those who did not. Infants who later developed autism had elevated fractional anisotropy at 6 months but then experienced slower change over time. By 24 months, infants with autism had lower FA values than those without autism. (SOURCE: University of North Carolina at Chapel Hill press release)
INTERVIEW
Dr. Jason Wolff, a post-doctoral fellow at the University of North Carolina School of Medicine and Carolina Institute for Developmental Disabilities, talks about why some scans have changed the way doctors think about autism.
Can you tell me about the study?
Dr. Wolff: This is the first study to come out of an ongoing longitudinal project where we are following kids who are at risk for autism. They are at risk by virtue of having an older sibling with the disorder, and we know that that puts them at about a 1 in 5 chance of having autism themselves. We are following them from 6 months up through about the age of 2 and throughout that time, we are conducting behavioral assessments and brain imaging. This first study takes a look at 92 of these high risk babies. We look back, once they reach the age of 24 months, we look back at the neuroimaging that we have done. For this study we looked at a type of imaging called diffusion tensor imaging, which follows the movement of water molecules through brain tissues. We can use that information to reconstruct how the brain might be wired. We looked at this imaging over time and how it changed from 6 to 24 months, based on those kids who went onto have autism and those you did not. Looking back, we find that the children who went onto have autism, we could see differences as early as 6 months and that over time their brains changed less. During this time, we expect that an infant's brain is rewiring itself quite a bit. We expect to see a great deal of change. For the kids with autism, their brains were not rewiring or reorganizing nearly as much as the children who went onto look more typical by the age of 2.
Can you tell me about the tension diffusor imaging?
Dr. Wolff: It is a pretty new kind of imaging. It has never been used as a diagnostic tool for autism and it is not really used diagnostically for almost anything at this point. It is still in fairly early phases but is becoming more popular and more refined.
Could you see any differences in behavior?
Dr. Wolff: We could see differences as early as 6 months and this is before we can really pick up any differences behaviorally. At 6 months, the children who go onto have autism do not look clinically different from the kids that do not go onto have autism. Seeing that there were some brain differences at 6 months was very novel. However, we only see those differences as an average for the groups. If I were to look at any one individual child, I could not say with any certainty what their outcome would be. It was just that there was an overall group difference. We still have a ways to go before we could use imaging or imaging combined with behavior to diagnose a child that early. There have been a number of studies that have followed children behaviorally over this time and they have found that you really do not see the first symptoms of autism until a child is past their first birthday. At 6 months those core symptoms just really are not present yet. However, our study will be looking into this more closely as well.
What could this finding kind lead to down the line?
Dr. Wolff: I think it tells us a couple of things. One is that this is an ongoing process. It is a story that unfolds. It is not as though a child suddenly has autism one day. It is a process that changes over time. It is perhaps a gradual process that eventually leads to autism, but getting there is something of a journey. What it tells us is that we could possibly intervene during that time leading up to autism and change the trajectory for an individual child. If we could go earlier and earlier with our interventions, we could prevent autism from fully manifesting for instance or at least improve the outcome of a child who is at very high risk for developing the disorder. It also tells us that there are a lot of different brain regions involved in autism, and that there are changes all across the brain in this early developmental period that are apparently very critical to the later outcome that we call autism. I think the hope is that as we improve our ability to use imaging and as the imaging itself improves and as we better understand what the behavioral trajectories look like we might be able to combine that information.
Why is autism so hard to detect?
Dr. Wolff: I think that part of it is that for a long time the field was looking for, understandably, a simple answer; a single cause or a single reason why autism develops and that by-in-large the conclusion has been reached that there are multiple causes. There are likely multiple genetic factors involved in what causes autism and because there are so many different factors involved, it really creates a puzzle and one that involves many potential factors. It takes some time to pull in data from many different sources and put together a clear picture of what autism looks like. The field has improved a great deal, however, and we are able to detect autism earlier than ever before.
Is that why they say autism is like a puzzle?
Dr. Wolff: That puzzle analogy is very apt for autism. It really does involve a lot of different pieces and the challenge of putting something together that makes sense.
How did this particular study help you understand autism better?
Dr. Wolff: I think a couple of things are really interesting to us. One is that this very early data shows that there are so many different brain regions involved. When we think about autism, we think about social symptoms and to a lesser extent repetitive behaviors, but many tend to view autism as a disorder of social communication. This data suggests that it is not limited to regions of the brain that involve social behavior, that it is really a whole brain phenomenon which lead to prominent social deficits down the line. Overall, autism is a general developmental phenomenon. Our study also tells us and confirms that autism is that evolving process. That it is one that is dynamic and that it occurs over time during a really critical interval in life. There is no time during the lifespan where the brain changes as much it does in the first couple of years of life. Seeing this unfolding leading up to autism, in some ways has a lot of promise for the sorts of interventions and early detection that we could possibly use during that period.
FOR MORE INFORMATION, PLEASE CONTACT:
Jason Wolff, Ph.D.
Carolina Institute for Developmental Disabilities
University of North Carolina at Chapel Hill
jason.wolff@cidd.unc.edu
