Obsessive-Compulsive Disorder & Chronic Pain

Until a few years ago, obsessive-compulsive disorder (OCD) was grouped into anxiety disorders by the American Psychiatric Association (APA). In 2013, the organization added a chapter specifically on OCD and related disorders to its Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Today,  practitioners continue to work through this new and distinct classification. Despite a scarcity of research linking OCD and related disorders to pain, it is important to be aw

The obsessions may take the form of persistent, intrusive thoughts or images of pain. Although catastrophizing is not the same as intrusive thoughts, engagement in this behavior in patients with chronic pain may provide some insight and support for this assertion.15

A number of case reports have detailed patients who overvalue their pain experience to the point of it being an obsession.16 Patients with complex regional pain syndrome, for example, may reveal bizarre perceptions, similar to a body dysmorphia, about a part of their body that they wish to amputate despite the prospect of further pain and functional loss.17 Patients with chronic pain receiving adequate relief with opioids also may hoard their medication, for example, to ensure a continuous supply by stockpiling reserves for a future need.18

Patients with OCD may also require treatment for pain conditions.

The compulsions consist of repetitive behaviors, such as rubbing, limping, guarding, or groaning, performed in response to the obsessive thoughts and images.1 Trichotillomania and excoriation, or skin-picking, are not perceived by the patient as self-harm but rather self-soothing behaviors. Both conditions fall under the body-focused repetitive behavior category, which is an umbrella term for impulse control behaviors that involve compulsively damaging one’s physical appearance or causing physical injury and, at times, added pain. Despite similarities, these cognitions and repetitive behaviors do not have the senseless or unrealistic quality of classic OCD symptoms. However, the psychological functions that these pain behaviors serve may be the same as those served by OCD.

Patients who struggle to control obsessions may take comfort in the ability to contain some component of aversive stimuli, such as exposure to physical pain.19 In other words, individuals with OCD might be willing to endure physical pain as a distraction from emotional distress, an expression of negative self-worth, or as a means to gain control over some aspect of suffering.19

This action, in turn, may lead to fear-avoidance behaviors. For example, a person with a cleaning obsession may suffer from lower back pain and avoid bending to place dishes into the dishwasher and instead wash them meticulously by hand. In addition, the kitchen sink may be low depending on the height of the individual, which would require the patient to hunch over, causing other pain and difficulties. Pain-anticipation and fear-avoidance beliefs can significantly influence the behavior of patients with chronic pain in that they motivate avoidance behavior.20

Providers must be aware of the powerful effects of these cognitive processes. There are different reasons why individuals may be averse to internal sensations. Unfortunately, a comprehensive model explaining the importance of hiding or expressing emotions is still lacking.

The lack of a common nomenclature for internal states and experiences is a barrier to better understanding this phenomenon, and there is much still to be learned about how people make sense of their internal worlds.19

Defining Related Disorders

APA’s new chapter distinguishes OCD from related disorders by identifying important differences. Some disorders are characterized by cognitive symptoms, such as perceived defects or flaws in appearance (eg, body dysmorphic disorder) or the perceived need to save possessions (ie, hoarding disorder). Others are characterized by recurrent body-focused repetitive behaviors, such as hair-pulling (eg, trichotillomania) and skin-picking (eg, excoriation).

Substance/medication-induced disorder is defined as having symptoms that are due to substance intoxication or medication withdrawal. OCD-related disorder due to another medical condition is described as involving symptoms characteristic of OCD that are the direct pathophysiological consequence of a medical disorder. Other specified/unspecified OCD consist of symptoms that do not meet criteria for a recognized disorder because of atypical presentation or uncertain etiology.1

Adding Hoarding Excoriation to the Mix

The new chapter on OCD and related disorders reflects the increasing evidence of these disorders’ relatedness to one another and, importantly, their distinction from other anxiety disorders. Two new disorders have been added to the DSM-5 and to this chapter: hoarding disorder and excoriation.1 APA’s addition of these unique diagnoses in DSM-5 was intended to increase public awareness, improve identification of cases, and stimulate research and development of specific treatments for these conditions.1

Hoarding disorder reflects the persistent difficulty with discarding or parting with possessions due to a perceived need to save the items and distress associated with discarding them. Beyond the mental impact of the disorder, the accumulation of clutter can create a public health and safety issue (eg, tripping and fire hazards). Hoarding disorder may have unique neurobiological correlates, is associated with significant impairment, and may respond to clinical intervention.1

Excoriation disorder is characterized by recurrent skin-picking resulting in medical issues, such as infections, skin lesions, scarring, and physical disfigurement. This disorder has strong evidence for its diagnostic validity and clinical utility.1 Symptoms can lead to clinically significant distress or impairment in social, occupational, or other key areas of functioning.