Note: While the term “autism spectrum disorder” (ASD) is utilized in the most widely used professional diagnostic manual, the DSM-5, we consider the differences associated with autism as an aspect of the individual’s identity rather than inherently being a disorder. Accordingly, identity-first language such as “autistic” is used throughout this writing, as preferred by many with lived experience.
In many ways, this is the best of times to be optimistic about the future of autistic individuals who have obsessive compulsive disorder (OCD). OCD and its treatment in autistic individuals, as well as how to effectively support family members, is receiving more attention in the scientific and clinical communities. This is already leading to the potential for improved outcomes for both children and adults, which is an extremely welcome development for a highly complex and compelling population. There is every reason to believe that the future of treating OCD in autistic people will only be brighter, as awareness of this issue and treatment methodologies continue to progress.
OCD is found at all levels of intellectual and functional ability, as well as across sex, gender, ethnicity, race, and socioeconomic status in autistic individuals. OCD often worsens issues associated with autism and is a barrier to autistic individuals reaching their full potential. We are still learning about how autistic individuals experience OCD, and the ways it might differ from the experiences of non-autistic persons.
It is important to be able to distinguish OCD from autism. However, this can be challenging since their symptoms often overlap. Therefore, let’s begin by discussing restrictive-repetitive behaviors (RRBs), the core feature of autism that on the surface most resembles OCD and is most prone to being confused with it.
Examples of RRBs are:
- Lining up or spinning objects
- Closing and opening drawers and doors
- Paying too much attention to a narrow range of topics or interests
- Behavioral rigidities
- Sensory issues
- Stereotyped movements
It is true that in certain cases RRBs can become so intertwined with OCD symptoms that knowing where one ends and the other begins often defies straightforward answers — even for experts. Nonetheless, there are some important distinctions to be made. The following can be used as a guide, though given the heterogeneity of each condition, there may be exceptions.
| Category | Restrictive-Repetitive Behaviors | OCD Symptoms |
| Function |
|
|
| Age of Onset | Before age 5 | Typically between 8–12 years old |
| Context | Universal - not necessarily sensitive to situational contexts, though maybe at times | Situational - occur or don’t occur depending on the circumstances |
| Experience | Desirable and/or pleasant, and/or soothing/regulating | Unwanted and/or intrusive |
Difficulties with Diagnosis
OCD tends to be more difficult to assess in autistic than non-autistic individuals. Measures of OCD such as the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and the CY-BOCS version for youth — in addition to being designed as treatment guides rather than diagnostic tools — were not developed with autistic individuals in mind. This should always be a consideration when conducting assessments of OCD in this population and interpreting findings, especially for women and girls, and certain ethnic and racial groups whose OCD symptoms may be especially prone to be missed or misunderstood. Ideally, the approach to assessing OCD in autistic individuals should be multidisciplinary and as comprehensive as possible, integrating present clinical and test findings with a thorough developmental and medical history. There is no single measure for diagnosing OCD, whether in autistic or non-autistic individuals, so a lot depends on the acumen of the clinician.
One practice that can go a long way toward making more accurate assessments of OCD in autistic persons is using measures that were designed and validated specifically for autistic individuals, such as:
Identifying OCD in autistic people is also impacted by a lack of clinicians who are well-versed in this area of practice. Clinicians working in mental health or developmental disability settings often have expertise in autism or OCD respectively but are often not as familiar with their co-occurrence. Undoubtedly, there is a great need for the continued expansion of training opportunities for clinicians in the assessment of autism and OCD presenting together. Another obstacle is that the assessment of mental health issues in autistic individuals may not be as well-integrated as possible into their other autism-related services. Consequently, within services primarily focusing on their developmental disability of autism, an appropriate diagnosis of OCD might be delayed or not made at all.
Communication deficits, another core feature of autism, can also make assessing OCD in autistic individuals more difficult. Although many autistic persons speak, some do not. Also, some autistic individuals who speak may be less verbal when dysregulated. Many autistic persons have difficulties in expressive and/or receptive language and nonverbal communication and may be extremely concrete using language in general, which potentially impedes the proper identification of OCD.
Another reason that OCD symptoms in autistic persons are often missed or do not get the attention they merit is that they are overshadowed by more pressing concerns, including other co-occurring conditions that disrupt daily life or involve self-injury. It is not uncommon for the clinical profile of autistic individuals with OCD to incorporate one or more of the following conditions — depression and other mood disorders, anxiety disorders, attention-deficit hyperactivity disorder (ADHD), Tourette syndrome and other tic disorders, or thought disorders.
Before leaving this section, it is important to note that autism is found far more in persons diagnosed with OCD than in the general population. Among individuals presenting for OCD treatment, there will be some who have felt pressured to learn to camouflage symptoms of autism to “fit in,” as well as others who are simply not aware they have autism. Moreover, autism is easy to confuse with OCD-related social issues, especially in persons with strong basic cognitive abilities. For these reasons, we recommend that clinicians screen for autism in individuals diagnosed with OCD whenever there are concerns regarding interpersonal functioning, social communication, or rigid behaviors.
Prevalence
Numerous studies have found that OCD and autism have genetic, neurobiological, familial, and behavioral commonalities. As a result, it makes sense for OCD and autism to occur together in certain people. But at what rate?
It’s not a question without some controversy. Although a high prevalence of OCD among autistic individuals had initially been consistently reported, many earlier studies did not adequately tease out autism-related perseverative thoughts from OCD-related obsessive thoughts, or autism-related RRBs from OCD-related compulsions. Interestingly, in those studies where specific guidelines were used to distinguish OCD from autism, significantly lower rates of comorbidity were reported.
This distinction is important and helpful when considering the findings of other studies. For example, one treatment study found that less than 10 percent of the sample reported compulsive or ritualized behaviors similar to those exhibited in OCD, but with no clearly identified desire to prevent a negative outcome (mealtime or travel rituals, wearing clothing in a particular fashion — all without the intent of avoiding a specific outcome).
More recent studies have suggested that there are both shared and distinct OCD presentations among autistic individuals. One of these studies found that autistic individuals with OCD endorsed similar patterns of checking, washing, and neutralizing behaviors to those endorsed by individuals with OCD only. However, they also endorsed significantly more OCD symptoms than individuals with autism only.