INTRODUCTION — Obsessive-compulsive disorder (OCD) is characterized by recurrent intrusive thoughts, images, or urges (obsessions), or by behavioral acts (compulsions) that the individual feels driven to perform. The obsessions typically cause anxiety or distress while compulsions are often in response to the obsessions or according to rules that must be applied rigidly. Most individuals with OCD have both obsessions and compulsions.
OCD typically starts in childhood or adolescence, persists throughout a person’s life, and produces substantial impairment in functioning due to the severe and chronic nature of the illness.
The epidemiology, pathogenesis, clinical manifestations, course, and diagnosis of OCD are described here. Pharmacotherapy, psychotherapy, and deep brain stimulation for OCD and topics on OCD in children and adolescents, as well as pregnancy and postpartum females are discussed separately.
●(See "Pharmacotherapy for obsessive-compulsive disorder in adults".)
●(See "Psychotherapy for obsessive-compulsive disorder in adults".)
●(See "Deep brain stimulation for treatment of obsessive-compulsive disorder".)
●(See "Obsessive-compulsive disorder in pregnant and postpartum patients".)
EPIDEMIOLOGY
Prevalence — The lifetime prevalence of obsessive-compulsive disorder (OCD) worldwide is estimated at 1.5 percent for women and 1.0 percent for men [1,2]. Estimated lifetime prevalence among adults in the United States is slightly higher, at 2.3 percent [2,3]. Females are affected at a slightly higher rate than males in adulthood, although males are more commonly affected in childhood [3,4].
Comorbidities — OCD is comorbid with many different disorders. The presence of comorbid conditions such as depression, tic disorders, or obsessive-compulsive personality disorder are associated with a lower response rate to treatment.
●Psychiatric disorders – Psychiatric disorders that are more commonly seen in individuals with OCD than the general population include:
•Anxiety disorders – In epidemiologic samples, 76 percent of individuals have a comorbid anxiety disorder including panic disorder (13 to 56 percent) [5], social anxiety disorder, generalized anxiety disorder (30 percent) [5], and specific phobia.
•Mood disorders – In epidemiologic studies, 63 percent of individuals with OCD have a lifetime history of a mood disorder, most commonly major depressive disorder (41 percent) [2]. Bipolar disorder appears to be present in up to 22 percent of individuals with OCD [5].
•Obsessive-compulsive personality disorder – In clinical studies, up to 32 percent of individuals have comorbid obsessive-compulsive personality disorder [6].
•Tic disorders – In clinical studies, up to 29 percent of individuals with OCD have a comorbid tic disorder. This is most commonly seen in males with childhood onset of OCD [7].
•Others – Body dysmorphic disorder, trichotillomania (hair pulling disorder), and excoriation (skin picking) disorder are more commonly seen in individuals with OCD than in the general population [8].
●Neurologic disorders – OCD is described in individuals with basal ganglia dysfunction such as Huntington disease, Sydenham chorea, and Parkinson disease [5]. It has also been described in temporal lobe epilepsy [5]. (See "Huntington disease: Clinical features and diagnosis" and "Sydenham chorea", section on 'Neuropsychiatric symptoms' and "Focal epilepsy: Causes and clinical features", section on 'Neuropsychiatric symptoms'.)
Additionally, evidence suggests potential associations between OCD and dementia [9,10] and OCD and ischemic stroke [11].
•Cognitive disorders/dementia – In a longitudinal study from the Taiwan National Health registry involving 1347 individuals with OCD, the risk of developing any dementia was greater than comparative controls (hazard ratio 4.28, 95% CI 2.96-6.21) [12]. The risk included the development of Alzheimer disease and vascular dementia. It is also possible that the obsessive-compulsive symptoms may be an early manifestation of dementia rather than dementia occurring as a complication of OCD.
•Ischemic stroke – In another longitudinal study (also using the Taiwan National Health registry) of over 28,000 individuals with OCD, OCD was associated with ischemic stroke (hazard ratio 3.02, 95% CI 1.91-4.77) [11]. The risk for hemorrhagic stroke did not differ between individuals with OCD and those without OCD (hazard ratio 0.87, 95% CI 0.42-1.8). The suggested mechanism is due to OCD being a systemic inflammatory disease; however, further investigation is warranted.
OCD appears to be more common in individuals with some psychiatric disorders than in the general population. When these disorders are diagnosed, we typically assess for OCD as well. These include schizophrenia or schizoaffective disorders (12 percent with OCD) [13,14], bipolar disorder [5], Tourette disorder (30 to 50 percent) [5,15], and eating disorders such as anorexia nervosa or bulimia nervosa (40 percent) [16]. (See "Tourette syndrome: Pathogenesis, clinical features, and diagnosis" and "Comorbid anxiety and depression in adults: Epidemiology, clinical manifestations, and diagnosis" and "Bipolar disorder in adults: Clinical features", section on 'Obsessive-compulsive disorder'.)
In some cases, there is symptomatic overlap in the presentation of individuals with OCD and comorbid disorders. Our discussion on differentiating these disorders is found below. (See 'Differential diagnosis' below.)
PATHOGENESIS — Studies suggest that genetic, neurobiological, infectious, and hormonal factors may contribute to the pathogenesis of obsessive-compulsive disorder (OCD) [17-29].
Genetic factors — Twin and family studies suggest that there is a genetic contribution to OCD with greater genetic influences in pediatric-onset OCD than in adult-onset OCD [19]. The precise genes involved in OCD are not known, although work in this area is ongoing [20-23].
Neurobiology — Numerous lines of research support a role for alterations in cortico-striato-thalamo-cortical (CSTC) circuits and/or neurochemical abnormalities to play a role in the pathogenesis of OCD.
●CSTC circuit alterations – Structural and functional imaging studies have found abnormalities in CSTC circuits in patients with OCD [17,30]. While there are inconsistencies among studies, the most commonly reported abnormalities occur in the orbitofrontal cortex, prefrontal cortex, the anterior cingulate cortex, striatum, hippocampus and the pallidum [31,32]. Furthermore, case reports show that neurosurgical alteration to CSTC circuits can reduce symptoms of OCD and new onset of OCD can occur after neurologic lesions such as ischemic stroke or traumatic brain injury [33-36].
Abnormalities in other brain regions have also been reported and the model for OCD now includes abnormalities in multiple brain circuits, not just CSTC circuits [37].
●Neurochemical abnormalities – Neurochemical abnormalities, including changes in serotonergic [38], dopaminergic [39], and/or glutamatergic [40-42] concentration are hypothesized to play a role in the pathophysiology of OCD. However, studies testing these hypotheses are inconclusive.
Other factors — Several other factors (eg, infectious, hormonal, and traumatic factors) have been implicated in OCD. However, causal associations have not been established [24]. As examples:
●Infectious – Pediatric autoimmune neuropsychiatric disorder associated with group A streptococcal infection (PANDAS) is associated with the onset or exacerbation of OCD in some children [25]. In PANDAS, OCD symptoms are hypothesized to be triggered by an autoimmune reaction to group A beta-hemolytic streptococci that damages the basal ganglia. However, as other infectious agents may trigger a similar acute neuropsychiatric syndrome [26], a broader syndrome called both pediatric acute-onset neuropsychiatric syndrome and childhood acute neuropsychiatric symptoms has been proposed. (See "PANDAS: Pediatric autoimmune neuropsychiatric disorder associated with group A streptococci".)
●Hormonal – Hormonal fluctuations may play a role in the development of OCD. New onset or exacerbation of OCD has been described in premenstrual and perinatal periods [27,28]. (See "Obsessive-compulsive disorder in pregnant and postpartum patients".)
●Stress/trauma – Stress may play a role in precipitating OCD [29]. Acute OCD onset has been reported in adults following exposure to traumatic events.
CLINICAL FEATURES
Obsessions and compulsions — Most individuals with obsessive-compulsive disorder (OCD) manifest both obsessions and compulsions; however, both are not necessary for a diagnosis [43,44].
●Obsessions – Obsessions are intrusive or unwanted repetitive or persistent thoughts, images, or urges that cause marked distress or anxiety. Obsessions often involve content that is odd, irrational, or of a seemingly magical nature (eg, harm will come if the closet is not arranged in a specific order). Individuals with OCD attempt to ignore, suppress, or neutralize these thoughts, often with another thought or behavior (compulsion).
●Compulsions – Compulsions (or rituals), repetitive behaviors (eg, washing, checking), or mental acts (eg, counting, repeating words silently) are behaviors that an individual feels driven to perform to reduce the distress triggered by an obsession or according to rules that must be applied rigidly.
While compulsions are often thematically related to an obsession (eg, washing rituals occur with obsessive fears of contamination), they are often not connected in a realistic way to the feared event or are clearly excessive. Examples of this may be arranging items symmetrically to prevent harm to a loved one, or showering for several hours daily to avoid illness.
The content, frequency, and severity of the symptoms vary widely among individuals. Some individuals have mild to moderate symptoms (spending one to three hours per day obsessing or doing compulsions), whereas others have near constant obsessions or compulsions that can be incapacitating. Certain common themes or “symptom dimensions” are identified. These include cleaning, need for symmetry, counting compulsions, forbidden or taboo thoughts (aggressive, sexual, or religious obsessions and related compulsions) and harm (to self or others). Symptom dimensions provide critical information that is used to tailor cognitive-behavioral therapy treatment.
Associated features — The presence of associated features may affect the level of psychosocial impairment. However, some of these features (eg, dysfunctional beliefs, avoidance behaviors) may be potential targets for psychotherapy. (See "Psychotherapy for obsessive-compulsive disorder in adults", section on 'Cognitive-behavioral therapy'.)
●Suicidality and thoughts of harm to others – The rates of suicidal thoughts and behaviors in individuals with OCD varies broadly among studies.
In a large collaborative survey including 3711 individuals with OCD, suicidal ideation in the past month was reported in 6 percent of individuals while a lifetime suicide attempt was reported in 9 percent [45]. However, in a meta-analysis investigating the relationship between individuals with OCD and suicidality, lifetime rates of suicidal ideation were as high as 64 percent (across 18 studies), while lifetime rates of suicide attempt were as high as 46 percent (across 22 studies) [46]. Additionally, worsening levels of suicidality in OCD patients are associated with comorbid axis I disorders, severity of symptoms, feelings of hopelessness, and past history of suicide attempts.
Some individuals with OCD manifest intrusive fears of harming others (eg, “harm” symptom dimension) (see 'Clinical features' above). There are no data suggesting that they are more likely to do so at a rate higher than the general population.
●Avoidance behaviors – Avoidance behaviors are often pervasive and may severely restrict functioning. In some cases, individuals with OCD avoid people, places, or things that trigger obsessions and compulsions. For example, individuals with contamination concerns might avoid public places (eg, restaurants, public restrooms) to reduce exposure to feared contaminants. Individuals with intrusive thoughts about causing harm to others may avoid social interactions.
●Dysfunctional beliefs – Dysfunctional beliefs may be present in individuals with OCD. These may be addressed in therapy using cognitive strategies [47]. Examples of dysfunctional beliefs include (see "Psychotherapy for obsessive-compulsive disorder in adults", section on 'Cognitive-behavioral therapy'):
•Inflated responsibility and the tendency to overestimate threat
•Perfectionism and the intolerance of uncertainty
•Overvaluing the importance of thoughts (eg, believing that having a forbidden thought is as bad as acting on it) and the need to control thoughts
These beliefs are present in individuals with other anxiety disorders as well.
●Level of insight – Individuals with OCD differ in the degree to which they believe that their obsessions and compulsions are excessive or unreasonable [43,44,48]. Insight can vary within an individual over the course of the illness. Poor insight has been linked in some (but not all studies) to worse long-term outcomes [49]. In a minority of people with OCD (≤4 percent) insight is absent such that their beliefs are delusional in nature. For example, an individual may be convinced that their thoughts can physically harm another person. (See 'Psychotic disorders' below.)
●Response to symptoms – Individuals with OCD may experience a wide range of affective responses to their obsessions or compulsions. In some cases, the response to the symptom may lead to further psychosocial distress. As an example, some individuals may experience marked anxiety or recurrent panic attacks, Others may feel disgust at themself for their behavior. The distress may persist until the individual attains a sense of “completeness” or until things look, feel, or sound “just right.”
CLINICAL COURSE AND COMPLICATIONS
Onset — In the United States, the mean age of onset of obsessive-compulsive disorder (OCD) is 19.5 years. Nearly 25 percent of cases begin by age 14 years [2,3]. Males tend have an earlier age of onset than females. Onset tends to be before age 10 in males and in adolescence in females [2]. Onset after age 35 years is unusual [50].
The onset of symptoms in OCD is typically gradual; however, acute onset has been reported, and has been associated with infectious etiology.
Course and effect of treatment — If untreated, the course of OCD is usually chronic, with waxing and waning symptoms while a minority have a deteriorating course [51,52]. (See 'Other factors' above.)
While many individuals with onset of OCD in childhood or adolescence will have lifetime symptoms, some individuals will remit by early adulthood [53]. In a meta-analysis of 16 studies individuals with OCD were followed for up to 15.6 years [54]. Forty percent of individuals (most treated with cognitive-behavioral therapy, pharmacologic management, or both) achieved remission (not meeting criteria for full or subthreshold OCD). Without treatment, rates of remission (usually defined as minimal to no symptoms) of OCD in adults are low (eg, 20 percent in a 40-year follow-up study of 144 patients) [51].
Remission rates in published research have varied based on comorbidity rates in the samples studied, treatment selection, how treatments were delivered, and how remission was defined. As an example, a trial found that adults with OCD who received optimally delivered evidence-based treatment for 12 weeks (ie, SRI, EX/RP, or SRI+EX/RP) had remission rates ranging from 25 to 58 percent depending upon the specific treatment received. Remission was defined as no more than mild symptoms [55]. (See 'Comorbidities' above.)
Effects on development, functioning, and quality of life — OCD is associated with impaired social and occupational functioning and reduced quality of life [56-58].
When OCD starts in childhood or adolescence, individuals may experience developmental difficulties. As examples, adolescents may avoid socializing with peers. Young adults may struggle to leave home and live independently. Individuals with OCD may try to impose rules and prohibitions on family members or other caregivers because of their disorder. This may result in the accommodation of rituals or participation in rituals. High accommodation is often associated with high expressed emotion. Together, these can contribute to poor treatment response, high family or caregiver burden, and poorer quality of life among those who live with individuals with OCD.
Impairments may be related to specific symptoms. As examples, obsessions about harm can make relationships with family and friends feel hazardous and result in avoidance. Obsessions related to symmetry can derail the timely completion of school or work projects. Additionally, individuals with contamination concerns may avoid health care settings due to fear of exposure to germs or may develop dermatologic problems (eg, skin lesions) due to excessive washing. In some cases, symptoms of OCD can interfere with its own treatment (eg, when medications are considered contaminated).
ASSESSMENT AND DIAGNOSIS
Assessment — We suspect a diagnosis of obsessive-compulsive disorder (OCD) in individuals with either intrusive, recurrent, or persistent thoughts, urges, or images, or in those with repetitive mental acts or repetitive behaviors. We treat individuals whose symptoms are time consuming (take more than one hour per day), or cause clinically significant distress or impairment. When possible, we obtain history from family members or other reliable sources in addition to the patient. We also evaluate for other features that may suggest alternative or coexisting disorders.
●Determining pathologic nature of symptoms – We differentiate symptoms due to OCD from other occasional intrusive thoughts or repetitive behaviors that may be common in the general population, by establishing how much time is consumed by the symptoms and the amount of distress associated with them. In OCD, symptoms are time consuming (eg, more than one hour spent per day with obsessions or compulsive behaviors) or cause significant distress in social or occupational functioning [59-61]. The frequency, amount of time consumed, and extent to which obsessions/compulsions cause the patient distress or interfere with their life helps to distinguish OCD from occasional intrusive thoughts or repetitive behaviors that are common in the general population (eg, double-checking that a door is locked) [59-61].
Furthermore, we assess whether there is a link between the compulsive behavior and obsessional symptoms and what the consequences might be of not performing a ritual or compulsion. Compulsions that are done as an attempt to neutralize obsessional thoughts or impulses are common in OCD and may be a helpful diagnostic clue. Individuals with OCD may perform rituals to avoid perceived harm (eg, showering repeatedly to avoid “contaminants” and subsequent illness).
●Evaluating for other symptoms or behaviors – Individuals with OCD may have symptoms commonly seen in other disorders. For example, individuals may manifest with severe anxiety and panic attacks (as in panic disorder), avoidance of social situations (as in social anxiety disorder), or difficulty discarding objects (as in hoarding disorder). In many cases comorbid diagnosis are present. We evaluate individuals with symptoms of obsession or compulsion for the presence of co-occurring psychiatric disorders. In cases where an individual meets criteria for both disorders, both are diagnosed. (See 'Differential diagnosis' below.)
Diagnosis — This diagnostic approach is in accordance with the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) diagnostic criteria for OCD [62]:
●A. Presence of obsessions, compulsions, or both:
Obsessions as defined by both:
•1. Recurrent and persistent thoughts, urges, or images that are experienced, at some time during the disturbance, as intrusive and unwanted, and that in most individuals cause marked anxiety or distress.
•2. The individual attempts to ignore or suppress such thoughts, urges, or images, or to neutralize them with some other thought or action (ie, by performing a compulsion).
Compulsions as defined by both:
•1. Repetitive behaviors (eg, hand washing, ordering, checking) or mental acts (eg, praying, counting, repeating words silently) that the individual feels driven to perform in response to an obsession, or according to rules that must be applied rigidly.
•2. The behaviors or mental acts are aimed at preventing or reducing anxiety or distress or preventing some dreaded event or situation; however, these behaviors or mental acts either are not connected in a realistic way with what they are designed to neutralize or prevent, or are clearly excessive.
●B. The obsessions or compulsions are time-consuming (eg, take more than one hour per day) or cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.
●C. The obsessive-compulsive symptoms are not attributable to the physiological effects of a substance (eg, a drug of abuse, a medication) or another medical condition.
●D. The disturbance is not better explained by the symptoms of another mental disorder, for example:
•Excessive worries, as in generalized anxiety disorder
•Preoccupation with appearance, as in body dysmorphic disorder
•Difficulty discarding or parting with possessions, as in hoarding disorder
•Hair pulling, as in trichotillomania (hair-pulling disorder)
•Skin picking, as in excoriation (skin-picking) disorder
•Stereotypies, as in stereotypic movement disorder
•Ritualized eating behavior, as in eating disorders
•Preoccupation with substances or gambling, as in substance-related and addictive disorders
•Preoccupation with having an illness, as in illness anxiety disorder
•Sexual urges or fantasies, as in paraphilic disorders
•Impulses, as in disruptive, impulse-control, and conduct disorders
•Guilty ruminations, as in major depressive disorder
•Thought insertion or delusional preoccupations, as in schizophrenia spectrum and other psychotic disorders
•Repetitive patterns of behavior, as in autism spectrum disorder
●Specifiers for OCD in DSM-5 – Specifiers for the disorder include assessments of the patient’s insight and presence/history of a tic disorder.
•Patient’s degree of insight into the illness
-With good or fair insight – The individual recognizes that OCD beliefs are definitely or probably not true or that they may or may not be true.
-With poor insight – The individual thinks OCD beliefs are probably true.
-With absent insight/delusional beliefs – The individual is completely convinced that OCD beliefs are true.
•Tic-related – The individual has a current or past history of a tic disorder. (See "Tourette syndrome: Pathogenesis, clinical features, and diagnosis", section on 'Obsessive-compulsive disorder'.)
Differential diagnosis — In diagnosing OCD, other disorders with overlapping features should be considered. We differentiate these disorders from OCD by careful review of symptoms including their course, quality, and presence of precipitating factors. In individuals who meet criteria for both disorders simultaneously, both are diagnosed.
Anxiety disorders
Generalized anxiety disorder — Recurrent thoughts that are present in generalized anxiety disorder are usually about real-life concerns such as work or school, while the obsessions in OCD usually are not. OCD-related concerns generally involve content that is odd, irrational, or of seemingly magical nature. In OCD, compulsions are almost always present and usually linked to the obsessions. (See "Generalized anxiety disorder in adults: Epidemiology, pathogenesis, clinical manifestations, course, assessment, and diagnosis".)
Specific phobia — Individuals with specific phobias, like those with OCD, may have a fear reaction to specific objects or situations. However, the feared objects in specific phobia are usually more circumscribed than those in OCD, and not characterized by rituals. (See "Specific phobia in adults: Epidemiology, clinical manifestations, course and diagnosis".)
Social anxiety disorder — In social anxiety disorder, the feared objects or situations are limited to social interactions or performance situations. Avoidance or reassurance-seeking is focused on reducing this social fear. (See "Social anxiety disorder in adults: Epidemiology, clinical manifestations, and diagnosis".)
Hoarding disorder — In hoarding disorder, symptoms focus exclusively on the persistent difficulty discarding or parting with possessions, marked distress associated with discarding items, and excessive accumulation of objects. The accumulation of objects is not a response to obsessional thoughts as in individuals with OCD. As an example, in OCD, the individual may have a compulsion to accumulate and retain objects in response to an obsession (ie, to attain a sense of completeness), while in hoarding disorder there is an inability to discard objects.
OCD spectrum disorders — Other disorders that include intrusive thoughts and repetitive behaviors can be distinguished from OCD by the nature of the thoughts and behaviors. These include:
●Body dysmorphic disorder – Individuals with body dysmorphic disorder focus on perceived defect(s) in appearance.
●Trichotillomania – The repetitive behavior is limited to hair-pulling and is not triggered by obsessions.
●Excoriation disorder – The repetitive behavior is limited to skin picking and is not triggered by obsession.
Tic disorders — A tic is a sudden, rapid, recurrent, nonrhythmic motor movement or vocalization (eg, eye blinking, throat clearing). Tics are typically less complex than compulsions and are not aimed at neutralizing obsessions. (See "Hyperkinetic movement disorders in children", section on 'Tic disorders' and 'Comorbidities' above.)
Obsessive-compulsive personality disorder — Obsessive-compulsive personality disorder is an enduring and pervasive maladaptive pattern of excessive perfectionism and rigid control that often leads to ritualized behavior. Obsessive-compulsive personality disorder is not a subsyndromal version of OCD, and is not characterized by obsessions. The repetitive behaviors in obsessive-compulsive personality disorder are not performed in relation to obsessions. (See "Overview of personality disorders" and 'Comorbidities' above.)
Major depressive disorder — The ruminative thoughts present in major depressive disorder are typically mood-congruent, are not necessarily experienced as intrusive, and rarely linked to compulsive behavior. This contrasts with OCD where the obsessive ruminations are intrusive and may have a link to compulsive behaviors. (See "Unipolar depression in adults: Assessment and diagnosis".)
Psychotic disorders — Diagnostic criteria for OCD were revised in DSM-5 to emphasize that a patient with OCD may lack insight into their illness or have obsessional beliefs that are delusional [62]. We distinguish OCD from delusional disorder or other psychotic disorder by the lack of associated symptoms such as hallucinations, disorganized thinking, or affective blunting that is seen with psychotic disorders. Individuals with OCD have obsessions and compulsions, typically without other features seen in psychosis. (See 'Comorbidities' above and "Psychosis in adults: Epidemiology, clinical manifestations, and diagnostic evaluation".)
Other disorders
●Anorexia nervosa – The intrusive thoughts and repetitive behaviors are limited to concerns about weight, food, or body image. (See "Anorexia nervosa in adults: Clinical features, course of illness, assessment, and diagnosis".)
●Illness anxiety disorder – Recurrent thoughts are exclusively related to fear of currently having a serious disease. Compulsions or associated repetitive behaviors may be present but are typically directed towards fears of illness (eg, repetitive tests or physical examinations).
●Somatic symptom disorder – In somatic symptom disorder, excessive thoughts, feelings, or behaviors are related to somatic symptoms or associated health concerns. Compulsions or repetitive behaviors may be present but are typically directed towards investigating perceive somatic symptoms (eg, repetitive tests or physical examinations).
Other behaviors that are sometimes considered “compulsive,” include sexual behavior (in the case of paraphilias), gambling (eg, pathological gambling), and substance use (eg, alcohol abuse). In these conditions, an individual generally derives pleasure from the activity (at least early in the illness) and may wish to resist it only because of its deleterious consequences. (See "Risky drinking and alcohol use disorder: Epidemiology, pathogenesis, clinical manifestations, course, assessment, and diagnosis".)
Determining severity — The standard scale for measuring OCD severity is the Yale-Brown Obsessive-compulsive scale (Y-BOCS) (figure 1) [63,64]; it consists of a checklist of obsessions and compulsions and a scale that assesses their severity. Baseline assessment of a new patient with OCD followed by routine reassessment over time is suggested to monitor the patient’s course of illness and response to treatment. The Y-BOCS has both an interviewer version and a self-report version [65]. Simpler self-report scales, the Obsessive Compulsive Inventory-Revised, the Florida Obsessive-Compulsive Inventory, and the Dimensional Obsessive-Compulsive Scale [66-68], provide alternatives to the Y-BOCS but there are tradeoffs in their use.
SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Obsessive-compulsive disorder and related disorders".)
SUMMARY AND RECOMMENDATIONS
●Epidemiology – The approximate lifetime prevalence of obsessive-compulsive disorder (OCD) worldwide is 1 to 1.5 percent. Lifetime prevalence in the United States is 2.3 percent. Females are affected at a slightly higher rate than males in adulthood, although males are more commonly affected in childhood. (See 'Prevalence' above.)
Psychiatric disorders such as anxiety disorders and mood disorders are more common in individuals with OCD than in the general population. OCD appears to be more common in individuals with schizophrenia, mood disorders, eating disorders, and tic disorders than in the general population. (See 'Comorbidities' above.)
●Clinical features – Most individuals with OCD manifest both obsession and compulsions. (See 'Clinical features' above.)
•Obsessions – Obsessions are intrusive or unwanted repetitive or persistent thoughts, images, or urges that cause marked distress or anxiety. Individuals with OCD attempt to ignore, suppress, or neutralize these thoughts, often with another thought or behavior (compulsion). (See 'Obsessions and compulsions' above.)
•Compulsions – Compulsions (or rituals), repetitive behaviors (eg, washing, checking), or mental acts (eg, counting, repeating words silently) are behaviors that an individual feels driven to perform to reduce the distress triggered by an obsession or according to rules that must be applied rigidly. (See 'Obsessions and compulsions' above.)
•Associated features – Associated features often seen in individuals with OCD include avoidance behaviors, dysfunctional beliefs, and varied level of insight. These may affect the level of psychosocial impairment. (See 'Associated features' above.)
There appear to be associations between OCD, suicidal thoughts or behaviors, and thoughts of harm to others. Rates of suicidal thoughts vary broadly among studies. Data do not suggest that individuals with OCD are more likely to harm others at a rate higher than the general population. (See 'Associated features' above.)
●Course – OCD typically starts in childhood or adolescence and persists throughout life. OCD is associated with impaired functioning and reduced quality of life. (See 'Clinical course and complications' above.)
●Assessment – We suspect a diagnosis of OCD in individuals with intrusive, recurrent or persistent thoughts, urges, or images, or in those with repetitive mental acts (eg, counting) or behaviors. We determine if the symptoms are pathological by assessing how much time is consumed by the symptoms and the level of distress associated with them. We also evaluate for other features that may suggest alternative or coexisting disorders (See 'Assessment' above.)
●Diagnosis – Diagnosis of OCD is made by the presence of obsessions, compulsions or both. The symptoms must be either time consuming (ie, more than one hour per day) or cause significant distress or impairment in social, occupational or other areas of functioning. (See 'Diagnosis' above.)
●Differential diagnosis – We differentiate OCD from other disorders by assessing for a link between the compulsions and underlying obsessions, the quality and course of the symptoms (eg, are symptoms limited to specific idea such as a perceived deficit in physical appearance), and the level of psychosocial distress. The differential diagnosis includes anxiety disorders, hoarding disorder, OCD spectrum disorders such as trichotillomania, tic disorder, obsessive-compulsive personality disorder, major depressive disorder, and psychotic disorders. (See 'Differential diagnosis' above.)
