In the last few years, there has been a noticeable increase in the number of children with Down syndrome who are also being diagnosed with autism spectrum disorder (ASD). Children who have autism, as well as Down syndrome, have a dual diagnosis. They have two co-existing conditions.

Earlier, many experts and parents believed that children couldn't have autism and Down syndrome together. This concept is gradually becoming dated with the continuous publication of longitudinal research on the behavior and affects of children with Down syndrome and ASD.

As of 2021, psychiatrists diagnose approximately 1 in 44 children in the US with Autism Spectrum Disorder (ASD). Every year, around 6000 babies are born with Down Syndrome in the US. Experts working with children with Down syndrome and ASD report that approximately 18% to 20% of all children with Down syndrome also have autism.

It makes Autism Spectrum Disorder and Down syndrome equal opportunity conditions. These disorders can affect any child irrespective of their geographic location, race, and socioeconomic status. While both these conditions can be difficult to manage, a dual diagnosis poses a unique set of challenges for the parents.

While Autism Spectrum Disorder and Down syndrome are developmental conditions, they have different causes, symptoms, treatment, and management.

What Is Autism Spectrum Disorder?

Autism spectrum disorder (ASD) or autism is a complex developmental condition. Individuals with autism spectrum disorder face persistent challenges involving social communication, repetitive behavior, and limited interests. It is a lifelong condition, but the range of signs and symptoms can vary significantly between two individuals with ASD.

The diagnosis of ASD can only be made by a child psychiatrist or psychologist. Sometimes, the signs of autism become noticeable when a child is between 2 and 3 years old. In several cases, the social communication and functional deficits related to autism become more pronounced only after the child begins school.

Some of the typical social communication deficits may include –

• Less to no interest in sharing of interest with others
• Trouble appreciating their own emotions as well as others’ emotions
• Difficulty in holding eye contact
• Difficulty in making friends
• Inflexible or robot-like speech
• Inability to grasp abstract ideas

Individuals with ASD may also have repetitive behaviors and restricted interests. These may include –

• Extreme difficulty in coping with change may even lead to outbursts
• Intense focus on topics and subjects that may not intrigue their neurotypical peers
• Hypersensitivity to loud noises, bright lights, or changes in temperature
• Inability to accept changes to routines or new experiences
• Stimming or repetitive movements like hand flapping or rocking back-and-forth
• Organizing things (toys, in the case of children) in a particular fixed manner

An early diagnosis of autism may allow the child and their family to access the resources necessary for their therapy. Although ASD is a lifelong condition, early intervention can help the child develop social interaction and communication skills.

There is NO cure for autism since it is a condition and NOT a disease. However, a child may benefit from speech and language therapy, behavior therapy, social skills training, special education, and parent management training.

What Is Down syndrome?

Down syndrome or trisomy 21 is a chromosomal disorder. The presence of an extra (entire or partial) copy of chromosome 21 causes down syndrome.

It is not hereditary. However, advanced maternal age may play a role in the higher risk of a child being born with Down syndrome.

Currently, prenatal screening allows the diagnosis of Down syndrome in utero. Doctors can diagnose the condition almost immediately after birth after direct observation as well. The diagnosis of DS is quite straightforward since it's based on direct observation or genetic (chromosomal) analysis.

The severity of down syndrome varies among individuals. It may be the cause of lifelong learning disorders, intellectual disability, and developmental delays. Depending on the severity of the condition the individual may also have additional health problems such as heart defects.

Most individuals with Down syndrome have distinct facial features that may include -

• Short neck
• Upward slanting eyelids
• A small head
• Flattened face
• Poor muscle tone
• Short hands with a single crease across the palm
• Small hands and feet with short fingers and toes
• Brushfield’s spots

The facial features may also vary between individuals with down syndrome. Infants diagnosed with DS typically show a slower growth rate and are shorter than their peers as they grow older.

Sadly, most children with DS show mild to moderate cognitive impairment. They may experience speech and language delays, along with learning-memory problems.

Apart from seeking speech and language therapy for toddlers with Down syndrome, remain in touch with their pediatrician. Research shows that individuals with DS may experience health complications. These may include heart defects, defects of the GI tract, sleep apnea, disorders of the immune system, problems of the spinal column, and weight management problems.

Therefore, getting routine medical care is extremely important for anyone with Down syndrome.

Is it Autism or Down Syndrome?

Autism Vs Down Syndrome: Causes

• Autism:  There is no determined cause of autism. Causes may be a combination of genetic and non-genetic factors.
• Down Syndrome: Partial or complete trisomy of Chromosome 21.
  

Autism Vs Down Syndrome: Diagnosis

• Autism:  Autism may be diagnosed early by a child psychiatrist or psychologist.
• Down Syndrome: Down Syndrome can be diagnosed via prenatal testing before birth or immediately after birth through direct observation.
  

Autism Vs Down Syndrome: Physical Traits

• Autism:  No physical traits are currently associated with autism
• Down Syndrome: Down syndrome is associated with distinct physical traits like distinctive facial features.

Autism Vs Down Syndrome: Mental/Intellectual abilities

• Autism:  Individuals with autism may have disabilities that range from learning difficulties to cognitive deficits.
• Down Syndrome: Those with mild to moderate Down syndrome may not have overt mental disabilities.

Autism Vs Down Syndrome: Social Communication

• Autism:  Those with autism may face difficulties in understanding social cues and communicating in social situations.
• Down Syndrome: Those with mild to moderate DS understand social cues and participate in social communication much more easily.
  
  

Dual Diagnosis: Autism and Down syndrome

When a child already has Down syndrome, diagnosing autism spectrum disorder can be challenging. Parents of children with DS need to observe, monitor and note any changes in behavior.

Here are some new behaviors or behavior changes you should notice in a child with both autism and down syndrome –

Younger Than 3 Years –

• Repetitive motor behavior
• Episodic eye movements
• Sudden and extreme refusal of specific food
• Atypical play with toys
• Regression of spoken language, gestures, and signs
• Impairment of receptive language
• Fascination with or staring at moving lights, fingers, or ceiling fans

Older Than 3 Years

• A history of developmental regression
• Atypical vocalizations
• Unusual sensory responsiveness
• Hyperactivity or hypoactivity
• Short attention span
• Resistance to changes in routine

Children older than 3 years with dual diagnosis may also show severe anxiety, agitation, fearfulness, and disruptive behavior in social situations. They may also experience disturbed sleep.

Signs in Teenagers

• Lack of social response
• Distant behavior with family or friends
• Absence of interest to form new relationships and maintain old ones
• Anxiety, fear, and agitation in the presence of new people
• Fascination or obsession with inanimate objects
• Extremely difficulty in adjusting to a new environment

Parents with children with DS should note that these behaviors are completely normal at certain points of development. Developmental regression is also expected in children with moderate to severe Down syndrome. However, when one or more of these behaviors become pervasive and extreme, your child may require an evaluation for autism spectrum disorder.

Autism in Children with Down syndrome: What Should You Do?

If you believe that your child will benefit from an evaluation, you should begin a close observation of their behaviors. When speaking with the healthcare provider, be sure to ask if they have experience with diagnosis and therapy of autism among children with Down syndrome.

It is also crucial that you remain informed as the primary caregiver. Here's what you can do to ensure that –

1. Boost your support system. Talk to your family members, friends, family doctor, and psychologist.
2. Learn more about autism in children with down syndrome from reliable sources.
3. Seek the services of a professional counselor or family therapist if you find yourself struggling with difficult emotions.
4. Join social media support groups for children with dual diagnoses.

Getting a correct formal diagnosis can help your child receive the proper school and services they need for a better quality of life.