Friday, May 7, 2010

What Causes Childhood Apraxia of Speech and Is It Preventable?

From CASANA

First, it is important for parents to understand that there is most likely nothing that you did to “cause” your child’s speech disability. It is not about how much you talked to your child or whether or not you had them in daycare, for example. Your child does not have apraxia because you separated from your spouse or because you moved to a new city. So while we know that parents have a strong role in healthy child development, unless there was abuse, neglect, or isolation, you are not responsible for causing your child’s speech disorder.

The current knowledge that we have about Childhood Apraxia of Speech (CAS) is this. CAS occurs in the following 3 conditions:

  • Neurological impairment caused by infection, illness, or injury, before or after birth or a random abnormality or glitch in fetal development. This category includes children with positive findings on MRI’s of the brain.
  • Complex Neurodevelopmental Disorders – We know that CAS can occur as a secondary characteristic of other conditions such as genetic, metabolic, and/or mitochondrial disorders. In this category would be Childhood Apraxia of Speech that occurs with Autism, Fragile X, Galactosemia, some forms of Epilepsy, and Chromosome translocations involving duplications and deletions.
  • Idiopathic Speech Disorder (a disorder of “unknown” origin) – with this condition, we currently don’t know “why” the child may have CAS. Children do not have observable neurological abnormalities or easily observed neurodevelopmental conditions.

Parents often ask if their child may have apraxia due to medical complications during pregnancy or childbirth. There are currently no studies that suggest a direct relationship between complications of pregnancy or childbirth and a specific increase in risk for apraxia of speech. For example, an umbilical cord wrapped around the neck of a fetus could theoretically cut off oxygen supply and possibly lead to neurological injury, eventually resulting in a CAS diagnosis. However, such a condition could also NOT result in CAS or even neurological injury. Some children are born just fine even though there was some complication during pregnancy or birth. So, while it is possible that a complication could result in neurological damage that might contribute toward a motor speech disorder like CAS, research has not told us when or how this would occur.

Some speculate that some forms of CAS and other childhood conditions may be a result, in part, of environmental conditions such as exposure to pollutants and toxins before or after birth. Others speculate that nutritional deficits or malabsorbtions cause CAS. We do know that, generally, toxins and nutritional deficits do cause some developmental problems, but to date these theories, as they relate specifically to CAS, are only speculations.

That said, a child’s positive health would contribute to their ability to benefit from their learning exposures and from therapy designed to help them. A child who is healthy is more fully capable of taking advantage of opportunities to learn. Children who are sick frequently with ear and sinus infections, enlarged tonsils and adenoids, asthma, allergies or have sleep disturbances, poor diets, attention and behavioral difficulties are going to find it much more difficult to benefit from the help provided. Helping your child be healthy and thus more “present” to the learning opportunities around them is one way parents can help.

Most likely in the future we will learn that CAS is caused by multiple factors and conditions, not one. To the extent that research evidence becomes available that CAS is caused by some factor(s) that can be manipulated to reduce or eliminate it, will determine whether or not it is preventable. Until then, we do know that appropriate speech therapy provided frequently and in consideration of motor-speech treatment principles offers the single most important opportunity for children with CAS to improve their speech capacity. Children who are able to maintain optimum health will most likely directly benefit the most from appropriate help.