Obsessive Compulsive and Related Disorders

The obsessive-compulsive and related disorders (OC-RD) category includes a range of diagnoses including obsessive compulsive disorder, body dysmorphic, trichotillomania, and excoriation disorders within the related disorders subsection.^1,2 These disorders differ in clinical expression, apparent motivational state, and affective responses. Studies find that nearly 40% of patients with OCD have comorbid conditions.³ These comorbidities include mood and anxiety disorders, anorexia nervosa, tic disorders, and ADHD. 

Studies estimate 17% of people with autism spectrum disorder (ASD) and 0.7-3.5% of people with intellectual disability (ID) experience OCD.^4-7 The presence of ASD and ID may overshadow estimates of the prevalence rates for OC-RD due to limitations in the capacity for self-awareness and self-reporting of inner experiences or insight. These limitations can make it difficult to distinguish obsessive compulsive behaviors from the core features of ASD (stereotypic, restrictive, and repetitive behaviors) or ritualistic behaviors in people with severe ID. Referrals for people with intellectual and developmental disabilities frequently involve high levels of co-occurring disruptive stereotypies and complex ritualistic behaviors, self-injury, and aggression.^8,9 The presence of comorbid ADHD, tic disorders, or specific behavioral phenotypes often lead to referral, and diagnosis of OC-RD emerges during these assessments. In many clinical settings, OC-RD is over-diagnosed based on overshadowing by repetitive or ritualistic behaviors. Accurate diagnosis requires defining the boundaries between compulsions and the restrictive-repetitive behaviors associated with ASD, and stereotypic and ritualistic behaviors in people with ID.^10,11  

A second set of overlapping issues involve boundaries with tic and other movement disorders, and the interrelationships with trauma (obsessions as intrusive images and thoughts), neurodegenerative disorders, and comorbid mental health disorders. Each of these issues interfaces with the developmental nature of OC-RD and its role in the assessment, treatment, and clinical course of OC-RD. Table 1 outlines many of these issues.

Diagnostic criteria¹ involve the presence of:

• At least one obsessive and one compulsive inclusion behavior
• Active involvement in these events for 1 hour per day
• Sufficient functional impairment
• An extensive list of rule outs and co-occurring disorders

RB is a 26-year-old male with ASD, borderline intellectual functioning, Tourette’s disorder, and compulsive hand washing. He failed to sustain improvement on standard treatments for OC-RD and Tourette’s disorder. As expected, the characteristic waxing and waning of his tic disorder complicated treatment, especially when changes in OC-RD symptoms were in synchrony with the severity of his tic disorder. 

His primary compulsion of hand washing arose amid contamination fears associated with agoraphobia and social avoidance. Anxieties about touching contaminated surfaces initiated his compulsive hand washing rituals. Now he fears contaminating others interspersed with catatonic episodes. These responded to lorazepam and clonazepam. He was admitted 
to a residential program where he responded to the structure and intensive behavioral interventions. Shortly after his discharge, a tropical storm dumped nearly 20 inches of rain in his area, and he regressed during the chaos surrounding this catastrophe.   

RB has taken 3 SSRIs (including fluvoxamine) augmented with SGA for both tics and OC-like symptoms. In addition, amantadine, memantine, riluzole, ondansetron, N-acetlycystiene, acomprosate, and low dose mu antagonists have been tried. The unsuccessful treatment approaches were integrated with an ongoing combination of increased structured activities outside the home, socials skills, and a very slow successive program of exposure and limiting time he could wash his hands (decreasing from three hours to under 30 minutes/day). These evolved as part of adapted cognitive behavioral therapy with exposure and response prevention (CBT- ERP) and habit reversal therapy (HRT) techniques. The modified HRT intervention was helpful initially, but his therapist left the practice and finding a replacement therapist comfortable with ASD was an issue. Restricted behaviors continued with active avoidance strategies such as keeping his hand in his pockets and not touching any objects except with his shoulder. He was reaching a point where deep/theta burst transcranial magnetic stimulation (TMS), direct current stimulation, or more invasive somatic procedures were under investigation.

Treatment Strategies^12-14

OC-RD is a heterogeneous group of repetitive behaviors with multiple etiologies and comorbidities. With new patients, clinicians may need to consider from a horizontal perspective the impact of each co-occurring/comorbid condition. This should remind clinicians that traumatic experiences can have a major impact on people with ASD, and relapsing OC-RD. In this case, the duration of the nonresponsive phase created, lack of insight, comorbid severe tic disorder, and long duration of symptoms, and repeated adverse life events can accentuate problems with sensitization and kindling like phenomena. For many, treatments begin with generalized strategies, which may be effective in two-thirds of patients. Each decision step beyond this point requires careful assessment and thoughtful intervention strategies. In cases with significant comorbidity, step one is to focus on combined interventions for the most problematic conditions. For example, in people with ASD and ID, ADHD and externalizing behaviors, OC-related symptoms and tic disorders are common co-occurring conditions. 

For complex referrals, OC-RD occurring in the context of IDD should be viewed longitudinally. The impact of genetic loading, gender dimorphism, and early age of onset generally have a negative impact on clinical course and treatment efficacy. By adulthood, many people like RB no longer present with a straightforward problem. A new diagnostic framework convened for RB must capture the evolving, intersecting trajectories of tic disorder, ASD, trauma, and environmental stressors — not as discrete pathologies, but as components of a lifelong developmental dynamic demanding integrative, individualized treatment planning.

Generalized Strategies for OC-RD:

• Cognitive behavioral therapy (CBT)
• Exposure cognitive behavioral therapy
• Exposure response prevention (ERP)
• Habit reversal training (HRT)

Common Psychopharmacologic Treatment Strategies for OC-RD

• SSRIs
• Clomipramine

Treatment for OC-RD is associated with Four Basic Approaches^12-16

TIER 1

Uncomplicated OCD

Treatment of uncomplicated OCD usually begins with CBT/ERP with modifications for ASD and ID. If ineffective or significant residual symptoms occur, then HRT is tried. This may accompany SSRI monotherapy. 

The best predictor of SSRI response is high harm avoidance temperament, suggesting behavioral inhibition, increased sensitivity to negative contingencies, internalizing symptoms, intolerance of uncertainty, and high threshold for risk taking. 

There are several caveats to declaring a tier 1 treatment approach ineffective: 

• Patients with OC-RD generally require a prolonged latency of response, longer duration of treatment, and higher doses of SSRI/SNRIs.
• Most treatment strategies contribute to improvement but fewer remissions, and rarely complete recovery from OC-RDs.
• The symptoms may wax and wane, intensify during periods of distress, loss, or trauma, and on occasion intensify after medical illnesses (beta- hemolytic strep, auto-immune, inflammatory/infectious diseases).
• Many people with chronic medical or neurological illness may also develop obsessions and rituals surrounding health care. These may require additional focus on the impact of the primary disorder and on the impact of chronic illnesses on psychological adaptation.
• OC and other repetitive behaviors can occur in several forms of neurodegenerative disorders. They are generally differentiated based on the co-occurrence of positive neurodiagnostic or genetic studies, and present with perseveration, difficulties with set shifting and declining neurocognitive and executive functions.

TIER 2

OCD-RD with Co-Occurring Tics

If standard Tier 1 treatment is ineffective or OC-RD co-occurs with tic disorders, the following should be considered:

• ERP/CBT/HRT, SSRIs augmented with alpha-agonists, or SGAs and/or in exceptional cases clonazepam.
• Treating OC symptoms and tics first means overcoming concerns about the adverse effects of treating psychiatric co-morbidities that can increase irritability, SIB, aggression, and increase repetitive behaviors associated with OC-RD. For example, stimulants used to treat ADHD might, in some cases, increase irritability in people with ASD.
• Remain aware of drug-drug interactions when using augmentation strategies. Reassess the need for combined treatments at frequent intervals. Remember the waxing nature of both OCD and tic disorders as well as the special ecological adaptations needed for ASD and ID.
• Clinical judgment and consultation or referral to peers and experts may be useful. These complex co-occurring conditions suggest more neuropharmacological heterogeneity. OC-RD is not a single neuro-transmitter condition, and NE, DA, GABA, glutamate, and neuropeptide/opioid are players in its pathophysiology.
• Consider the presence of genetic disorders associated with SIB (e.g., Lesch-Nyhan syndrome), neurodegenerative disorders, cerebrovascular conditions, and TBI. Both ASD and ID are associated with behavioral phenotypes and a large array of genetic and metabolic disorders.

TIER 3

OC-RD with Psychiatric Comorbidities

Comorbidities might include ADHD, mood disorders, anxiety, TBI, impulse control disorders, trauma/PTSD, schizophrenia, substance use, and fronto-temporal dementia. In these situations, treat the primary condition first. See other chapters of this guide for treatment recommendations for these conditions.

TIER 4

OC-RD, ID, and ASD

Research on alternative biological treatments has excluded people with IDD/ASD in controlled studies of TMS, direct electrical current, treatment for PANS or PANDAS, deep brain stimulation, or capsulotomy. 

OC-RD is a heterogeneous group of repetitive behaviors with multiple etiologies and comorbidities. For many people, treatment begins with generalized strategies (CBT/ERP/HRT and SSRIs/clomipramine). These may be effective in two-thirds of patients. Each decision step beyond this point requires careful assessment and thoughtful intervention strategies. Combined therapies are common, but we must do our best to avoid unnecessary polypharmacy, and apply ecological interventions, and psychotherapies in each subsequent treatment tier.

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