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5|25: Celebrating Five Years of Autism Science Day 17: Recovery from Autism Spectrum Disorders

February 17, 2010 Leave a comment

In honor of the anniversary of Autism Speaks’ founding on Feb 25, for the next 25 days we will be sharing stories about the many significant scientific advances that have occurred during our first five years together. Our 17th item, Recovery from Autism Spectrum Disorders, is from Autism Speaks’ Top 10 Autism Research Events of 2008. 

For decades, autism spectrum disorders have been assumed to be life-long conditions. Recently, evidence has begun to emerge suggesting that a significant minority of children with well-documented autism spectrum disorder (ASD) can recover; in 2008 the first research publication to define and review recovery was released, placing the percentage of children who recover in the range of 3-25%.

In December 2008, a team of researchers from the University of Connecticut and their colleagues published an inspiring and provocative article documenting cases of recovery in autism. Recovery was defined as previously having had clearly defined ASD but currently no longer meeting criteria for any ASD. Furthermore, the recovered individual is now learning and using skills with a “quality that reaches the trajectory of typical development in most or all areas.” Using these criteria, the research team documented and followed a group of children, now between 8-18 years of age, with a history of ASD who are now “recovered.” The authors point out that children who recover from autism may nevertheless be at risk for other challenges, such as subtle difficulties with some aspects of language, anxiety, or learning disabilities.

In a previous study, the same researchers reported several cases of ASD that evolved into ADHD with no autism. Interestingly, most of these children had evidence of early regression and recurrent ear infections. Most had also received early intensive behavioral intervention. Recent outcome studies have shown that core symptoms of autism tend to improve by adulthood, especially difficulties in the areas of communication. Several outcome studies have found that about 10-20 percent of adults previously diagnosed with ASD no longer meet criteria for the condition.

How can recovery occur? One clear possibility is that successful treatment moved children who had ASD off of the spectrum. However, as the researchers point out, since most children who receive even the best and most intensive intervention do not recover, treatment alone cannot be the explanation. Both treatment and inherent characteristics of the child are likely to explain recovery. The research team therefore looked for child characteristics that predict optimal outcome, identifying higher IQ, receptive language ability, verbal and motor imitation, motor development, and an early age at diagnosis and initiation of treatment as promising predictors. In the majority of studies that report recovery, behavior intervention was used alone or in combination with other therapies.

The authors point out that although early intervention is associated with optimal outcome, this fact should not be used as an argument against the need for intervention in older children in light of the growing evidence of brain plasticity throughout the life span. Finally, this thoughtful article considers a wide range of biological mechanisms that may help explain the process of recovery. Future research directions will now provide us with insights into ways of improving the outcomes – and the chances for recovery – for all individuals with ASD.

Update since this story was first run: In 2009 researchers reported in the journal Pediatrics that they had used the National Survey for Children’s Health, a voluntary, parent-reported survey, to examine ASD prevalence in the US. Among other surprising results, they discovered that a substantial portion of parents reported their children had previously been diagnosed with an ASD but did not currently have the condition.

5|25: Celebrating Five Years of Autism Science Day 16: Insights into Causes and Prevention of Premature Deaths in Autism

February 16, 2010 Leave a comment

Cuddling up with the Fragile X model mouse: new clues to sensory sensitivities in ASD

February 13, 2010 Leave a comment

A Single Diagnostic Category for Autism?

February 10, 2010 6 comments

Today the American Psychiatric Association announced plans to change autism diagnostic categories in the newest version of the Diagnostic and Statistical Manual (DSM).  Notably, it has been proposed that the diagnoses of Asperger syndrome and Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS) be removed from the manual.  A broad category of Autism Spectrum Disorder has been proposed instead.

These proposed changes are certain to be met with a wide range of reactions, and such reactions will depend on one’s perspective.  From the scientific perspective, research conducted over the past decade has shown that there is no strong scientific rationale for distinguishing among autism, Asperger syndrome, and PDD-NOS.  For example, research has shown that these subtypes are not linked to specific etiologies (causes) or specific treatment recommendations.  Studies have shown that autism and Asperger syndrome can show up in the same familes and that specific autism risk genes don’t aggregate neatly within diagnostic categories. Treatment recommendations for Asperger syndrome versus high-functioning autism or for autism versus PDD-NOS are not different.  So, from a scientific point of view, the changes in the DSM make sense.  The new classification system recognizes that autism is a spectrum disorder that varies quantitatively in symptom severity and expression.  The changes will allow us to look at the the landscape of autism broadly and focus on clusters of symptoms and seek etiological commonalities in disrupted signaling pathways that promise to tell us more than we have learned from considering each diagnostic category separately.

People in the community living with autism spectrum disorders may have a very different viewpoint, however.  For some individuals who have been diagnosed with Asperger syndrome or other subtypes of the ASD spectrum, the change in the DSM will be very disruptive and distressing. Many individuals personally identify with the diagnostic label they have been given and grown up with.  They may participate in support or advocacy groups that identify with a specific label, for example “Aspies”.  Thus, although the scientific and professional communities may institute a change in the diagnostic criteria, many may choose to use the original labels despite the changes in the DSM.  And there is nothing wrong with this.  In fact, there is precedent for this.  For example, “sensory integration disorder” and “nonverbal learning disability” are examples of labels that have been used by the clinical community, but are not specifically part of the DSM.

One potential positive impact of the proposed changes to the DSM is that they may help increase access to services to those individuals with Asperger syndrome and PDD-NOS who previously were denied access to autism-related services. From the perspective of a parent who is struggling with their young or adult child’s symptoms, it hardly matters what name is given to the collection of their symptoms. Increased access to services can help ease the burden of symptoms for those struggling to manage them.

We need to be respectful and compassionate about what a diagnostic change might mean for individuals with ASD and their families.  We invite you use this space to share your thoughts about this change and what it means to your family.  We will be listening and look forward to hearing your perspective.

Autism Speaks Science Staff Reports on New Parental Age and Autism Risk Study

February 9, 2010 Leave a comment
A new study of parental age and autism risk was published online yesterday in the journal Autism Research.  The study reports on approximately 5 million births in California from 1990-1999 and reaffirmed previous data showing that parents who are older have an increased risk of having a child with autism. The study found that, regardless of the father’s age, mothers over 40 had a 51% increase in risk of having a child with autism compared with younger mothers (aged 25-29). Fathers over 40 had 36% increase in risk compared to younger fathers,  but only when the mother was in the younger range.

These numbers may sound alarming, but lets further discuss what they mean.  The 51% increase in risk for mothers over 40 can also be described as approximately 1.5 times the chances of having a child with autism compared to mothers 25-29.  In other words, the increased chance of having a child with autism was less than two-fold among this group. Thus, mother’s age and father’s age only slightly increased the risk for autism, and should not be viewed as a specific cause of autism. While the exact biological mechanism behind the relationship between delayed parenthood and ASD is unknown and warrants further investigation, it is well understood that pregnancy in older individuals is associated with higher risk for low birth weight, prematurity, and chromosomal abnormalities.  We also know that prematurity is a risk factor for autism spectrum disorders (ASD).  It also is important to keep in mind that the majority of pregnancies in older fathers and mothers are healthy.

Do changes in the ages at which parents are having children explain the dramatic increase in prevalence of ASD?  The study examined births over a decade, a period during which the prevalence of ASD has increased by over 600%.  The authors estimated that advanced maternal age only accounts for 4.6% of the increase in autism cases in California during the study period.  Thus, it is clear that, while changes in the age at which parents are having children may account for some of the increase in prevalence of autism, a large amount of the increase in prevalence remains unexplained.

As with any study, there are many methodological details to be considered.  The strength of this study lies in the large population considered. These findings reinforce other data reporting parental age is a risk factor for autism.  The study population came from the California Department of Developmental Services (DDS), which is estimated to capture about 75-80% of all “true” autism cases.  To be included in the DDS, parents had to actively seek out services.  As such, parents of autism cases in the DDS are likely to have higher levels of education and socioeconomic status, and are perhaps older than what would be found in a population-based sample. We know from this and other research that higher levels of education and sociecomic status are associated with higher rates autism (perhaps because people in this demographic category are more likely to seek diagnostic services), so it is possible that this study may overestimate the effect of parental age on autism risk. Also, it is worth noting that this study considered cases of autistic disorder only, not diagnoses from the rest of the autism spectrum.

To summarize, it is important to remember that as we dig deeper into different contributions to autism risk, we will uncover different pieces of the larger puzzle that may not seem to fit, at least at first.  Some, pieces, like this one regarding parental age, are especially intriguing because they blend biological with the socio-environmental factor of delayed parenthood.   As for biology, it is also true that as people age, modifications occur in the way the genetic code is read. This field of research known as epigenetics and is one part of the larger study of gene x environment interactions.  The topic of gene-environment interaction has been reaching our community with increasing frequency and so Autism Speaks staff and some Guest Scientists will be offering a series of blog posts specifically on these topics.  Please stay tuned. We look forward to putting this puzzle together with you.

To learn more about the recent findings in autism epidemiology, including additional findings on the effects of parental age, please see our list of the Top Ten Science Accomplishments of 2009.

Reference: Shelton JF, Tancredi DJ and Hertz-Picciotto I (2010) Independent and Dependent Contributions of Advanced Maternal and Paternal Ages to Autism Risk. Autism Research.  3: 1-10.

5|25: Celebrating Five Years of Autism Science Day 5: Diagnosis at 14 Months

February 5, 2010 Leave a comment

In honor of the anniversary of Autism Speaks’ founding on Feb 25, for the next 25 days we will be sharing stories about the many significant scientific advances that have occurred during our first five years together. Our fifth item is Diagnosis at 14 Months.

In a study in the Archives of General Psychiatry, researchers from the Kennedy Krieger Institute in Baltimore, Maryland found that autism can be diagnosed at close to one year of age, which is the earliest the disorder has ever been diagnosed. The study, which evaluated social and communication development in autism spectrum disorders (ASD) from 14 to 36 months of age, revealed that approximately half of all children with autism can be diagnosed around the first birthday. The remaining half will be diagnosed later, and their development may unfold very differently than children whose ASD is diagnosable around the first birthday. Early diagnosis of the disorder allows for early intervention, which can make a major difference in helping children with autism reach their full potential

Researchers examined social and communication development in infants at high and low risk for ASD starting at 14 months of age and ending at 30 or 36 months. Half of the children with a final diagnosis of ASD made at 30 or 36 months of age had been diagnosed with the disorder at 14 months, and the other half were diagnosed after 14 months. Through repeated observation and the use of standardized tests of development, researchers identified, for the first time, disruptions in social, communication and play development that were indicative of ASD in 14-month olds. Multiple signs indicating these developmental disruptions appear simultaneously in children with the disorder.

The current study reveals that autism often involves a progression, with the disorder claiming or presenting itself between 14 and 24 months of age. Some children with only mild delays at 14 months of age could go on to be diagnosed with ASD. The researchers observed distinct differences in the developmental paths, or trajectories, of children with early versus later diagnosis of ASD. While some children developed very slowly and displayed social and communication abnormalities associated with ASD at 14 months of age, others showed only mild delays with a gradual onset of autism symptoms, culminating in the diagnosis of ASD by 36 months.

If parents suspect something is wrong with their child’s development, or that their child is losing skills during their first few years of life, they should talk to their pediatrician or another developmental expert. This and other autism studies suggest that the “wait and see” method, which is often recommended to concerned parents, could lead to missed opportunities for early intervention during this time period.

To read the complete story, including the signs of developmental disruptions for which parents and pediatricians should be watching, please click here http://www.autismspeaks.org/inthenews/landa_study.php.

Update since this story was run: Members of the Baby Siblings Research Consortium, a collaboration between Autism Speaks and the National Institute of Child Health and Human Development, have now published multiple scientific studies demonstrating that early signs of autism can reliably be seen as early as 12-14 months of age. This improved understanding of the early signs and symptoms of autism has permitted development of new measurement tools to both quantify and diagnose autism symptoms earlier than ever before. For example, the Autism Observational Scale for Infants or AOSI was published by Autism Speaks’ grantees in 2008 and is currently a part of many protocols involving early autism diagnosis and intervention. It has been shown to accurately detect autism as early as 12 months of age. In addition, a modification of the ADOS, called the ADOS-t, was released in 2008 to enhance the clinical diagnosis of autism, indicating a range of concern for children as young as 12 months of age. Both tools are huge advances in the field of diagnosis, allowing for reliable early detection and placement in appropriate intervention services.

5|25: Celebrating Five Years of Autism Science Day 1: New AAP Policy and Guidelines

February 1, 2010 Leave a comment

In honor of the anniversary of Autism Speaks’ founding on Feb 25, for the next 25 days we will be sharing stories about the many significant scientific advances that have occurred during our first five years together. Our first item, New AAP Policy and Guidelines, is from Autism Speaks’ Top 10 Autism Research Events of 2007.

After years of parents urging for earlier diagnosis and better treatments, the American Academy of Pediatrics (AAP) issued two new clinical reports in October 2007 that will help pediatricians recognize autism spectrum disorders (ASDs) earlier and guide families to effective interventions.

The first report provides detailed information on signs and symptoms so that pediatricians can recognize and assess ASDs in their patients. More specifically, the report introduces universal screening, which means pediatricians must now conduct formal ASD screening on all children at 18 and 24 months regardless of whether there are any concerns. The second report reviews educational strategies and associated therapies, which are the cornerstones of treatment for ASDs, and confirms that early intervention is crucial for effective treatment. The report states that a child diagnosed with autism should be actively engaged in intensive intervention at least 25 hours per week, 12 months per year, with a low student-to-teacher ratio allowing for sufficient one-on-one time. The report further states the importance for pediatricians to become knowledgeable about complementary and alternative medicine (CAM) therapies, ask families about current and past CAM use, and provide balanced treatment information.

The new guidelines will hopefully assure that at-risk children are finally appropriately referred without further delay. Both reports are part of a new AAP toolkit for pediatricians “AUTISM: Caring for Children with Autism Spectrum Disorders: A Resource Toolkit for Clinicians,” which includes screening and surveillance tools, guideline summary charts, management checklists, developmental checklists, developmental growth charts, early intervention referral forms and tools, sample letters to insurance companies and family handouts.

Update since this story was first run:  To respond to the AAP recommendations for evaluation by primary care providers of 18 and 24 months olds with suspected ASDs, in 2009 members of Autism Speaks’ High Risk Baby Siblings Research Consortium (BSRC) published an article in Pediatrics outlining several early signs of autism that physicians and other health care providers should be aware of.  The paper also identifies potential screening tools that may be used to detect early behavioral indicators.  Importantly, the authors address the challenges that primary care providers face in communicating the meaning of these early signs and symptoms.

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