Doctors have recently confirmed that autism and OCD frequently occur together. Autism and OCD initially appear to have little in common, yet studies indicate that up to 84% of people with autism have some form of anxiety and as many as 17% might have OCD. Additionally, an even greater proportion of people with OCD might also have undiagnosed autism. A 2015 study in Denmark tracked the health records of almost 3.4 million people over 18 years, and researchers found that people with autism are twice as likely as those without to be diagnosed with OCD later in life. The same study found that people with OCD are four times more likely than others to later be diagnosed with autism.
It can be tough to sort it all out. OCD rituals can resemble the repetitive behaviors that are common in autism, and vice versa. Also, people with either condition may have unusual responses to sensory experiences. Some autistic people find that sensory overload can readily lead to distress and anxiety, and the social problems people with autism experience may contribute to their anxiety as well. Anxiety is a huge component of OCD also, so it gets complicated.
How do we distinguish the two, or determine if someone has both conditions? It is interesting to note that people with both OCD and autism appear to have unique experiences, distinct from those of either condition on its own. Also, a crucial distinction found in this analysis is that obsessions spark compulsions but not autism traits. Another finding is that people with OCD cannot substitute the specific rituals they need with different rituals. Says Roma Vasa, director of psychiatric services at the Kennedy Krieger Institute in Baltimore, Maryland:
“They [those with OCD] have a need to do things a certain way, otherwise they feel very anxious and uncomfortable.”
People with autism, on the other hand, often have a repertoire of repetitive behaviors to choose from. They just need to perform rituals that are soothing, not necessarily a particular behavior.
More research is needed, not only in the area of diagnoses, but also treatment. The gold standard treatment for OCD is a Cognitive Behavioral Therapy (CBT) known as exposure and response prevention (ERP) therapy, but for those with both autism and OCD, it often does not work well. Whether this is due to auditory-processing difficulties, cognitive inflexibility, or something else, might vary from person to person. Researchers are trying to adapt CBT for people with autism, and agree that a personalized variation of the therapy can be beneficial.
We have a long way to go in figuring out just how OCD and autism are connected. Hopefully, just knowing there is a connection, however, should help clinicians when they are diagnosing and treating their patients.