Stomach pains...
Gastrointestinal (GI) problems are common in children with autism. That is not an earth-shattering statement and I have blogged about that before. Studies have shown GI problems to be prevalent in 24-70 per cent of the autism population.
Why such a difference?
Those statistics are from what is a called cross-sectional study -- that is like taking a photo of someone jumping. By looking at that photo, can you really tell how much time they spent in the air? No. That is the same logic for why those statistics vary so much -- they are taking a snapshot in time. Interestingly, no longitudinal studies, a.k.a long-term observational studies, have been done on autism and GI issues until a great piece of research titled "One-year course and predictors of abdominal pain in children with autism spectrum disorders: The role of anxiety and sensory over-responsivity" was published in 2014.
Is there something better?
A longitudinal study provides repeated observations of the same individual. Why is that important? Because now changes in the same individual can be studied, potentially revealing a sequence of events. That is powerful stuff. Unfortunately, longitudinal studies take long amounts of time and it is difficult to keep track of people for extended periods. However, this longitudinal study investigating autism and GI problems could really provide key insight into the disease.
It gets better!
Fantastically, these researchers also wanted to include anxiety and sensory issues in their observational study. Why is that awesome? Anxiety has been found to be experienced in the autism population anywhere from 40-84 per cent. Sensory issues are now defined as a core symptom of autism. Sensory issues are more formally termed sensory over-responsivity and indicates that distress, avoidance or hypervigilance occurs as a person's response to certain sensory input, a.k.a turning on certain lights, putting on certain clothes, etc. So needless to say observing GI issues, sensory issues, and anxiety in a longitudinal study among those with autism and seeing if one symptom impacts another is really exciting because vital information could be learned that could improve the daily living of so many people.
So let's get into the experiment...
This study examined 225 children with autism (ages 2.4 to 17.4) enrolled in the Autism Speaks Autism Treatment Network, which is a consortium of 17 autism centers in the US and Canada. In this cohort, 86.7 per cent were male and 85.3 per cent were Caucasian. Data was collected at enrolment, a.k.a baseline, and then one year later. Sensory over-responsivity was measured using a subset of questions from the Short Sensory Profile, which the parents answered.
Anxiety was measured using the DSM-Oriented Anxiety Problems T-score from the Child Behavior Checklist. And abdominal pain was measured from parent responses to the GI Symptom Inventory Questionnaire.
So how were these kids feeling at baseline?
25.8 per cent were experiencing chronic abdominal pain. Let that settle for a minute. That means within three months of starting this study, 57 kids with autism were experiencing abdominal pain that lasted over three months!! Yes, 57 kids were in pain for over three months! Just imagine trying to focus on academic tasks while being in pain, every day. Can you imagine how hard it is to function? Can you imagine how hard it is to parent when your child is in constant pain? Not easy, but here is something that pains my heart even more. 86.7 per cent of those initial 57 kids continued to have chronic abdominal pain at their one-year follow-up appointment. Whoa, that is heartbreaking. Then at the one-year follow-up appointment 23.8 per cent of those who initially didn't have abdominal pain did have chronic abdominal pain. But that is just the pain aspect of the experiment.
What about anxiety and the sensory issues?
At baseline, they found anxiety and sensory issues to be negatively correlated (r=-.42, p
What about predicting future symptoms?
When the researchers looked at the baseline data in ways to help predict symptoms, they found that in those without abdominal pain at baseline, sensory issues were a significant predictor of chronic abdominal pain at follow-up (p=.002). That is powerful information, for a parent or a doctor! All symptoms are important to address but now we have scientific evidence that for some with autism, one symptom can be a predictor of future symptoms. Go ahead, pick your jaw up from the floor. Mine dropped too when I first read this.
And here comes the holy grail...
The fact that sensory issues were a predictor of chronic abdominal pain lead the researchers to conclude their findings support the theory that hypersensitivity could be an underlying cause of GI problems. Let me quickly tell you about the holy grail of GI disease. There is a theory called visceral pain hypersensitivity (VPH), which states that there is enhanced pain in the gut in response to both painful and non-painful stimuli. What is a non-painful stimuli you ask? Good question. Food. Anyone have a picky eater?
And so...
These researchers put forth the model that sensory issues are a substantial predictor of future abdominal pain based on their 225 person, year-long autism study. They found that children who were initially dealing with chronic abdominal pain also were more likely to be having problems with anxiety and sensory issues. Additionally, they found that anxiety and sensory issues are closely coupled. Yes, more research needs to be done but we now have one symptom that can predict future symptoms for some with autism. Sensory issues are not trivial!!
Theresa Lyons, MS, MS, PhD is an Ivy League scientist, medical strategist, autism advocate, and Mama Bear. Want to heal your child from autism now? Click here to get the 5 Steps to Start Healing Autism.