Information for Providers

Autism spectrum disorder (ASD) is a set of complex neurodevelopment disorders that include autistic disorder, Asperger disorder, and pervasive developmental disorder not otherwise specified. Children who have ASD display mild to severe impairments in social interaction and communication along with restricted, repetitive, and stereotyped patterns of behaviors, interests, and activities. Diagnosis of ASD should be based on comprehensive behavioral evaluations, making diagnostic assessment complex and time-consuming. (From CDC)

The reported prevalence of ASD has increased in recent decades. For example, data from the Centers for Disease Control and Prevention’s (CDC) National Health Interview Survey (NHIS) revealed a nearly fourfold increase in parent-reported ASD between the 1997–1999 and 2006–2008 surveillance periods, and CDC’s Autism and Developmental Disabilities Monitoring (ADDM) Network revealed a 78% increase in ASD prevalence between 2002 and 2008.

The prevalence of parent-reported ASD among children aged 6–17 was 2.00% (1 in 50) in 2011–2012, a significant increase from 2007 (1.16%: 1 in 88). In 2011–2012, school-aged boys were more than 4 times as likely as school-aged girls to have ASD (3.23% compared with 0.70%).

The magnitude of the increase was greatest for boys and for adolescents aged 14–17. Cohort analyses revealed consistent estimates of both the prevalence of parent-reported ASD and autism severity ratings over time. Children who were first diagnosed in or after 2008 accounted for much of the observed prevalence increase among school-aged children (those aged 6–17). School-aged children diagnosed in or after 2008 were more likely to have milder ASD and less likely to have severe ASD than those diagnosed in or before 2007. (From CDC).

The recurrence risk of ASDs among children with an older affected sibling was recently estimated to be 18.7%, with an almost threefold increased risk for male subjects and an additional twofold increased risk if there was >1 older affected sibling.

Citation: Ozonoff S, Young GS, Carter A, Messinger D, Yirmiya N, Zwaigenbaum L, et al. (2011): Recurrence risk for autism spectrum disorders: a Baby Siblings Research Consortium study. Pediatrics. 128:e488-495.

Currently, ASD symptoms typically can be identified in children as young as 18 months, and the American Academy of Pediatrics recommends developmental screening of all children by age 24 months. Nevertheless, many children with ASD—especially those with only mild or limited speech delays—may not be diagnosed until they are of school age, when parents become concerned about an inability to make friends and teachers notice difficulties with peer interactions. Formal diagnoses may also occur at this age because a named disability (such as ASD) is needed for school-aged children to qualify for special education services under the Individuals with Disabilities Education Act. (From CDC).

As children age from birth to 18 years of age the neural pathways and myelination patterns in their brains are progressively established—decreasing the opportunities for interventions to maximize outcomes. That is why diagnosing autism as early as possible is so important. The earlier the diagnosis of autism is made, the easier it is to change the behavior of children with autism.

Harvey J. Kliman, MD, PhD, research scientist in the Department of Obstetrics, Gynecology & Reproductive Sciences at the Yale University School of Medicine, and his collaborators have determined that abnormal placental folds (invaginations) and microscopically identifiable trophoblast inclusions (TIs) may be key markers to identify newborns who are at risk for ASD.

Kliman and his colleagues showed in a recent publication that ASD at-risk placentas had as many as 15 trophoblast inclusions, while none of the control placentas had more than 2 trophoblast inclusions. Placentas from the at-risk pregnancies had eight-fold increased odds of having two or more trophoblast inclusions compared to control placentas. The presence of two or more trophoblast inclusions yielded a sensitivity of 41% and a specificity of 92% for predicting autism risk status. Four or more trophoblast inclusions yielded a sensitivity of 19%, a specificity of 99.9%, a positive likelihood ratio of 242, and—based on the most recent CDC prevalence data of 1 in 50 children—would conservatively predict an infant with a 96.7% probability of being at risk for autism. Five or more trophoblast inclusions would predict an infant at risk for autism with a 99.6% probability.

These studies are the basis of the PlacentASD® Test:

• Anderson GM, Jacobs-Stannard A, Chawarska K, Volkmar FR, Kliman HJ. (2007) Placental Trophoblast Inclusions in Autism Spectrum Disorder, Biological Psychiatry, 61:487-91.
• Walker CK, Anderson KW, Milano KM, Ye S, Tancredi DJ, Pessah IN, Hertz-Picciotto I, Kliman HJ, (2013) Trophoblast Inclusions are Significantly Increased in the Placentas of Children in Families at Risk for Autism, Biological Psychiatry 74:204-11.
  
  
  

If your patient’s child has a positive PlacentASD® Test, we will refer the family to services and professionals that may be able to help them.

In addition, we will refer the family to services that can help your patient maximize their current insurance coverage so their child will have access to the best possible services that are available.