INSAR 2022: Central Sensitivity Syndromes in Autism: Emerging Evidence about Chronic Pain in Autistic Adults
By Dr. Fakhri Shafai, AIDE Canada
Conference Summary: The International Society for Autism Research (INSAR) is the largest autism research conference in the world. This year’s conference took place May 11 – 14 and was a hybrid conference with both remote and in-person events being held in Austin, Texas. There has been a push in recent years to elevate autistic voices and the “nothing about us without us” movement has led to additional events to provide a platform for autistic individuals to share their perspectives. Additional events about culture, diversity, and expanding the number of autistic individuals who are collaborating as equal partners in research projects. Topics for research panel sessions are chosen based on proposals around the world that are in line with the stated goals of the INSAR community.
INSAR 2022 Session: Chronic Physical Health Problems in Autistic Adults
Presentation: Autism and Chronic Ill Health: An Observational Study of Symptoms and Diagnoses of Central Sensitivity Syndromes in Autistic Adults
Presenting Author: S. Louise Grant, King’s College London
Additional Authors: S Norton, King’s College London; R Weiland, V Vrije Universitiet Amsterdam; A Scheeren, Vrije Universitiet Amsterdam; S Begeer, Vrije Universitiet Amsterdam; R Anna Hoekstr, King’s College London
Background: Central Sensitivity Syndrome (CSS) is an umbrella term for a group of health conditions that include chronic pain issues. All of these are thought to include sensitisation (more sensitivity) of the central nervous system. Some common diagnoses that may be related to CSS include:
Chronic headaches, Migraine, Cluster headaches
Chronic fatigue syndrome
Ehlers Danlos Syndrome
Chronic muscle pain/tightness
Temporomandibular disorders (TMJ), clenching/grinding teeth while sleeping
Irritable Bowel Syndrome (IBS)
Restless legs syndrome
Chronic pelvic pain including possible painful menstruation
Chronic bladder pain including possible need to urinate frequently
Chronic skin problems including eczema, excessive dryness, rashes, etc.
Neck injuries (including whiplash)
Sensory sensitivities (especially to bright lights/strong odors)
CSS may also co-occur with common cognitive or mental health issues including:
Anxiety disorders and panic attacks
PTSD, especially if due to childhood trauma
Difficulty with attention, memory, and/or concentration
INSAR presentation: How does CSS relate to autism?
The presenting researchers found that autistic individuals were more likely to be diagnosed with conditions that are commonly found in CSS, suggesting that there is a great deal of overlap between symptoms of CSS and the physical health and mental health conditions commonly associated with autism. Up to 60% of autistic individuals tested in this study met or exceeded clinical criteria for a CSS diagnosis (versus estimates of 2-20% in the neurotypical population), and CSS was more common in autistic women than autistic men. Anxiety and sensory sensitivity were the best predictors of whether an autistic person was likely to be diagnosed with CSS, with individuals who were highly anxious and/or sensitive to sensory input being the most likely to also be diagnosed with CSS. The authors concluded that medical professionals need to be aware of the high overlap between autism and CSS conditions, and to pay close attention to chronic pain issues in autistic women.
What causes CSS?
CSS is not fully understood at this time, but sensitized cells in the nervous system are believed to either amplify messages of pain from the body or send messages that something that is not painful in fact will be interpreted as pain. There are some indications that it may involve issues with the immune system, the endocrine (hormone) system, and inflammation. It may run in families, and has been found to be more common in people who experienced abuse or trauma in childhood.
There may be a stressor that acts as a trigger for CSS. This could be a biological trigger (e.g., infection), physical trauma (e.g., a car accident), or psychological stress (e.g., a traumatic incident). Poor sleep, stress, depression, anxiety, and overexertion can all make symptoms worse.
How is CSS diagnosed?
CSS is not a single diagnosis based on one condition but is relevant when a person has some combination of the previously mentioned issues. The Central Sensitization Inventory (CSI) was developed as a self-assessment questionnaire with two parts. Part A includes 25 questions of common CSS symptoms that are rated on a scale of 0-4, with ‘never’ being 0 points and ‘always’ being 4 points.
Total scores are broken down into the intensity they represent:
Subclinical: 0 to 29
Mild: 30 to 39
Moderate: 40 to 49
Severe: 50 to 59
Extreme: 60 to 100
Part B asks patients to identify whether they have been officially diagnosed with certain disorders common in CSS. Only Part A is scored.
You can take and score the CSS and score it yourself:
English Central Sensitization Inventory
French Central Sensitization Inventory
What can I do with this information?
While there is not an official test that leads to a CSS diagnosis (e.g., no single blood test or scan can confirm it), knowing whether someone has a ‘clinically relevant’ score (defined as 40 points or more) on the CSI it can help physicians narrow down the best course of treatment to better manage a patient’s pain. Knowing whether it is CSS and seeing all the different issues a patient is dealing with can help doctors consider whether they should recommend:
Physical activity: For some issues related to CSS, aerobic exercise, strength training, and/or movement or flexibility training can offer some relief.
Medication: Certain drugs, such as non-steroidal anti-inflammatory drugs, acetaminophen (a common over-the-counter pain reliever), serotonin inhibitors (SNRI or SSRI), or tricyclic compounds commonly used for depression, may be prescribed at low doses.
Sleep management: One of the strongest triggers for flare ups of chronic pain conditions is poor sleep. Working on developing better sleep habits can have a dramatic impact on the level of pain a person experiences on a day-to-day basis. For more information on how to improve your sleep habits, check out this short animation written by leading Canadian researcher, Dr. Penny Corkum: Developing Healthy Sleep Habits
BC Women’s Hospital & Health Centre: What is Central Sensitivity Syndrome?
Dorsal Health: Central Sensitization: What is it and how do you treat it?
INSAR 2022 Presentation: Grant, SL; Norton, S.; Weiland, R.; Scheeren, A.; Begeer, S.; Hoekstr, R. A., “Autism and Chronic Ill Health: An Observational Study of Symptoms and Diagnoses of Central Sensitivity Syndromes in Autistic Adults”. May 13, 2022.
Adams, L. M., & Turk, D. C. (2015). Psychosocial factors and central sensitivity syndromes. Current rheumatology reviews, 11(2), 96–108. https://doi.org/10.2174/1573397111666150619095330
Neblett, R. The central sensitization inventory: A user’s manual. J Appl Behav Res. 2018; 23:e12123. https://doi.org/10.1111/jabr.12123
Nijs J, Malfliet A, Ickmans K, Baert I, Meeus M. Treatment of central sensitization in patients with 'unexplained' chronic pain: an update. Expert Opin Pharmacother. 2014;15(12):1671-83. doi:10.1517/14656566.2014.925446
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