Obsessive-Compulsive Disorder 

Obsessive-compulsive disorder (OCD) is a relatively common, if not always recognized, chronic disorder that is often associated with significant distress and impairment in functioning. Due to stigma and lack of recognition, individuals with OCD often must wait many years before they receive a correct diagnosis and indicated treatment.

OCD has a wide range of potential severity. Many patients with OCD experience moderate symptoms. In severe presentations, this disorder is quite disabling and is appropriately characterized as an example of severe and persistent mental illness.

OCD is classified in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) as an anxiety disorder.^[1] It is characterized by distressing intrusive obsessive thoughts and/or repetitive compulsive actions (which may be physical or mental acts) that are clinically significant.

Some experts have suggested that OCD should be removed from the anxiety disorders section of the DSM-IV-TR and grouped with putatively related conditions in the forthcoming DSM-5. A study by Bienvenu et al suggest that on the basis of comorbidity and familiality, OCD appears to be related both to anxiety disorders and to some conditions currently classified in other sections of DSM-IV-TR.^[2]

Go to Anxiety Disorders for more complete information on OCD and other anxiety disorders.

DSM-IV-TR criteria for obsession

Obsessions are defined in the DSM-IV-TR by the following 4 criteria:

• Recurrent and persistent thoughts, impulses, or images are experienced at some time during the disturbance as intrusive and inappropriate and cause marked anxiety and distress. Persons with this disorder recognize the pathologic quality of these unwanted thoughts (such as fears of hurting their children) and would not act on them, but the thoughts are very disturbing and difficult to discuss with others.
• The thoughts, impulses, or images are not simply excessive worries about real-life problems.
• The person attempts to suppress or ignore such thoughts, impulses, or images or to neutralize them with some other thought or action.
• The person recognizes that the obsessional thoughts, impulses, or images are a product of his or her own mind (not imposed from without, as in thought insertion).

DSM-IV-TR criteria for compulsion

Compulsions are defined by the following 2 criteria:

• An individual performs repetitive behaviors (eg, hand washing, ordering, checking) or mental acts (eg, praying, counting, repeating words silently) in response to an obsession or according to rules that must be applied rigidly. The behaviors are not a result of the direct physiologic effects of a substance or a general medical condition.
• The behaviors or mental acts are aimed at preventing or reducing distress or preventing some dreaded event or situation. However, these behaviors or mental acts either are not connected in a way that could realistically neutralize or prevent whatever they are meant to address or they are clearly excessive.

At some point during the course of the disorder, the person recognizes that the obsessions or compulsions are excessive or unreasonable (although this does not apply to children).

The obsessions or compulsions cause marked distress, are time consuming (take >1 h/d), or significantly interfere with the person's normal routine, occupational or academic functioning, or usual social activities or relationships.

If another Axis I disorder is present, the content of the obsessions or compulsions is not restricted to it, such as preoccupation with food and weight in the presence of an eating disorder, hair pulling in the presence of trichotillomania, concern with appearance in body dysmorphic disorder, preoccupation with drugs in substance use disorder, preoccupation with having a serious illness in hypochondriasis, preoccupation with sexual urges in paraphilia, or guilty ruminations in the presence of major depressive disorder.

Parenting style or upbringing does not appear to be a causative factor in OCD.

The additional specification of "with poor insight" is made for an individual with OCD if, for most of the current episode, the person does not recognize that the symptoms are excessive or unreasonable.

Obsessions and their related compulsions (the latter also referred to as rituals) often fall into 1 or more of several common categories, as seen in the table below.

Table. Categorizing Obsessions and Compulsions (Open Table in a new window)

Individuals often have obsessions and compulsions in several categories, and may have other obsessions (eg, scrupulosity, somatic obsessions, physical or mental repeating rituals). Often, the first pathologic obsession that an individual may experience is fear of contamination.

OCD should not be confused with obsessive-compulsive personality disorder (OCPD). The diagnosis of OCPD refers to an individual who has "a pervasive pattern of preoccupation with orderliness, perfectionism, and mental and interpersonal control, at the expense of flexibility, openness, and efficiency, beginning by early adulthood." They often display perfectionism, excessive devotion to work, rigidity, and/or miserliness (for further details, see DSM-IV-TR).^[1]

Despite the similarities in labels, relatively few individuals with OCD also meet the criteria for OCPD and vice versa.

Although OCD is categorized as an anxiety disorder in the DSM-IV-TR, Dr Eric Hollander has proposed that it should instead be considered an impulse control disorder, along with disorders such as trichotillomania, kleptomania, and pathologic gambling, which would make up an obsessive-compulsive spectrum of disorders.^{[3, 4]} However, this remains a controversial proposal.^[5]

The fact that obsessive-compulsive symptoms seem to often take very stereotypic forms has led some to hypothesize that the pathologic disturbance causing OCD may be disinhibiting and exaggerating some built-in behavioral potential that humans have that, under other ancestral circumstances, would have an adaptive function (eg, primate grooming rituals).

The exact process that underlies the development OCD has not been established. Research and treatment trials suggest that abnormalities in serotonin (5-HT) neurotransmission in the brain are meaningfully involved in this disorder. This is strongly supported by the efficacy of serotonin reuptake inhibitors (SRIs) in the treatment of OCD.^{[6, 7]}

Evidence also suggests abnormalities in dopaminergic transmission in at least some cases of OCD. In some cohorts, Tourette disorder (also known as Tourette syndrome) and multiple chronic tics genetically co-vary with OCD in an autosomal dominant pattern. OCD symptoms in this group of patients show a preferential response to a combination of serotonin specific reuptake inhibitors (SSRIs) and antipsychotics.^[8]

Functional imaging studies in OCD have demonstrated some reproducible patterns of abnormality. Specifically, magnetic resonance imaging (MRI) and positron emission tomography (PET) scanning have shown increases in blood flow and metabolic activity in the orbitofrontal cortex, limbic structures, caudate, and thalamus, with a trend toward right-sided predominance. In some studies, these areas of overactivity have been shown to normalize following successful treatment with either SSRIs or cognitive-behavioral therapy (CBT).^[9]

These findings suggest the hypothesis that the symptoms of OCD are driven by impaired intracortical inhibition of specific orbitofrontal-subcortical circuitry that mediates strong emotions and the autonomic responses to those emotions. Cingulotomy, a neurosurgical intervention sometimes used for severe and treatment-resistant OCD, interrupts this circuit (see Treatment and Management).

Similar abnormalities of inhibition are observed in Tourette disorder, with a postulated abnormal modulation of basal ganglia activation.

Attention has also been focused on glutamatergic abnormalities and possible glutamatergic treatments for OCD.^[10] Although modulated by serotonin and other neurotransmitters, the synapses in the cortico-striato-thalamo-cortical circuits thought to be centrally involved in the pathology of OCD principally employ the neurotransmitters glutamate and gamma-aminobutyric acid (GABA).

Genetic influence in OCD

Twin studies have supported strong heritability for OCD, with a genetic influence of 45-65% in studies in children and 27-47% in adults.^[11] Monozygotic twins may be strikingly concordant for OCD (80-87%), compared with 47-50% concordance in dizygotic twins.^[12] Several genetic studies have supported linkages to a variety of serotonergic, dopaminergic, and glutamatergic genes.^{[13, 14, 15, 16, 17]}

Other genes putatively linked to OCD have included those coding for catechol-O-methyltransferase (COMT), monoamine oxidase-A (MAO-A), brain-derived neurotrophic factor (BDNF), myelin oligodendrocyte glycoprotein (MOG), GABA-type B-receptor 1, and the mu opioid receptor, but these must be considered provisional associations at this time. In some cohorts, OCD, attention deficit hyperactivity disorder (ADHD), and Tourette disorder/tic disorders co-vary in an autosomal dominant fashion with variable penetrance.

Infectious disease and OCD

Case reports have been published of OCD with and without tics arising in children and young adults following acute group A streptococcal infections. Fewer reports cite herpes simplex virus as the apparent precipitating infectious event.

It has been hypothesized that these infections trigger a CNS autoimmune response that results in neuropsychiatric symptoms (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections [PANDAS]). A number of the poststreptococcal cases have reportedly improved following treatment with antibiotics.

Other neurologic conditions

Rare reports exist of OCD presenting as a manifestation of neurologic insults, such as brain trauma, stimulant abuse, and carbon monoxide poisoning.

Stress and OCD

OCD symptoms can worsen with stress; however, stress does not appear to be an etiologic factor.

Parenting and OCD

As previously mentioned, parenting style or upbringing does not appear to be a causative factor in OCD.

Incidence of OCD in the United States

Once believed to be rare, OCD was found to have a lifetime prevalence of 2.5% in the Epidemiological Catchment Area study.^[18] Current estimates of lifetime prevalence are generally in the range of 1.7-4%. Discovery of effective treatments and education of patients and health care providers have significantly increased the identification of individuals with OCD.

Incidence of OCD internationally

International studies have shown a similar incidence and prevalence of OCD worldwide.

OCD appears to have a similar prevalence in different races and ethnicities, although specific pathologic preoccupations may vary with culture and religion (eg, concerns about blaspheming are more common in religious Catholics and Orthodox Jews).

The overall prevalence of OCD is equal in males and females, although the disorder more commonly presents in males in childhood or adolescence and tends to present in females in their twenties. Childhood-onset OCD is more common in males.

It is not uncommon for women to experience the onset of OCD during a pregnancy, although those who already have OCD will not necessarily experience worsening of their symptoms during pregnancy.

Women commonly experience worsening of their OCD symptoms during the premenstrual time of their periods. Women who are pregnant or breastfeeding should collaborate with their physicians in making decisions about starting or continuing OCD medications.

Symptoms of OCD usually begin in individuals aged 10-24 years.

OCD is a chronic disorder with a wide range of potential severities. Without treatment, symptoms may wax and wane in intensity, but they rarely remit spontaneously.

Overall, close to 70% of patients entering treatment experience a significant improvement in their symptoms. However, OCD remains a chronic illness, with symptoms that may wax and wane during the life of the patient.

Roughly 15% of patients can show a progressive worsening of symptoms or deterioration in functioning over time.

Approximately 5% of patients have a complete remission of symptoms between episodes of exacerbation.

Pharmacologic treatment is often prescribed on a continuing basis; if a successfully treated individual discontinues their medication regimen, relapse is not uncommon. However, patients who successfully complete a course of CBT (perhaps as few as 12-20 sessions) may experience enduring relief even after the treatment, although some evidence shows that having CBT continue in some extended but less frequent fashion may further decrease the risk of relapse.

A certain percentage of patients may have disabling, treatment-resistant symptoms. These patients may require multiple medication trials and/or referral to a research center. A small subgroup of these patients may be candidates for neurosurgical intervention.

Education about the nature and treatment of OCD is essential. As with many psychiatric disorders, patients and their families often have misconceptions about the illness and its management. Information should be provided about the neuropsychiatric source of the symptoms, as opposed to having families unnecessarily blame themselves for causing the disorder.

A helpful book on OCD, written for the general public, is Dr Judith Rapoport's The Boy Who Couldn't Stop Washing,^[19] which discusses the recognition of OCD in individuals and the identification of effective treatments for the disease.

Patients and their families should be provided with information on support groups and should have opportunities to discuss the impact the illness has had on their self-experience and on their relationships.

The Obsessive-Compulsive Foundation is a self-help and family organization founded in 1986 that offers information and resources regarding OCD and related disorders (including contact information for various types of affiliated support groups, contact information listing psychiatrists and therapists who are experienced in the treatment of OCD, research opportunities, and book reviews).

Some other organizations offer more specialized resources, (eg, the San Francisco Bay Area Internet Guide for Extreme Hoarding Behavior, the Madison Institute of Medicine's Obsessive Compulsive Information Center, which provides information and a monthly newsletter for individuals with OCD symptoms of scrupulosity about religious/moral issues).

A more complete listing of OCD resources appears as an appendix in the APA Practice Guideline for OCD.^[20]

Several self-help books are also available, including Dr Edna Foa and Dr Reid Wilson's book,^[21] which can add CBT-style self-treatment to the educational experience they provide.

Useful Web sites include the following:

• The National Institute of Mental Health (NIMH), Obsessive-Compulsive Disorder, OCD
• The Mayo Clinic, Obsessive-compulsive disorder (OCD)
• WebMD, Obsessive-Compulsive Disorder