Obsessive-Compulsive Disorder: Pathological Doubt, Insight, Comorbidity

Pathological Doubt

Pathological doubt is a common feature of patients with OCD who have a variety of different obsessions and compulsions. Indi-viduals with pathological doubt are plagued by the concern that, as a result of their carelessness, they will be responsible for a dire event. They may worry, for example, that they will start a fire because they neglected to turn off the stove before leaving the house. Although many patients report being fairly certain that they performed the act in question (e.g., locking the door, un-plugging the hairdryer, paying the correct amount on a bill), they cannot dismiss the nagging doubt “What if?” Such patients often describe doubting their own perceptions. A 42-year-old man felt incapable of throwing grocery bags away because he feared he might not have completely emptied them. Immediately after star-ing into an empty bag, he inevitably thought, “What if I missed something important in there?”

Excessive doubt and associated feelings of excessive re-sponsibility frequently lead to checking rituals. For example, individuals may spend several hours checking their home be-fore they leave. As with contamination obsessions, pathologi-cal doubt can lead to marked avoidance behavior. Some patient become housebound to avoid the responsibility of potentially leaving the house unlocked. Pathological doubt is also embed-ded in the cognitive framework of a number of other obsessions. Patients with aggressive obsessions may be plagued by the doubt that they inadvertently harmed someone without knowing that they did so.

Insight

An awareness of the senselessness or unreasonableness of ob-sessions (often referred to as insight) and the accompanying struggle against the obsessions (referred to as resistance) have generally been considered fundamental components of OCD and its diagnosis. However, during the past century there have been numerous descriptions of patients with OCD who are completely convinced of the reasonableness of their obsessions and need to perform compulsions. In 1986, Insel and Akiskal described sev-eral such patients and presented the hypothesis that patients with OCD have varying degrees of insight and resistance, with ob-sessive–compulsive psychosis at one extreme of a hypothesized continuum. They also noted a fluidity between neurotic (i.e., as-sociated with insight) and psychotic states in these patients.

Degree of insight in OCD was addressed during the DSM-IV field trial in which patients were asked if they feared consequences other than anxiety if they did not perform their compulsions (Foa and Kozak, 1995). Fifty-eight percent believed that harmful consequences would occur. The degree of certainty that their obsessions were reasonable ranged across the entire spectrum of insight: 30% were uncertain whether they actually needed to perform their compulsions to avoid harm; however, 4% were certain and 26% were mostly certain. Again, this find-ing supports the notion that patients with OCD do not always maintain good insight but rather have varying degrees of insight. Although patients may be aware that their obsessions are exces-sive – that is, recognizing that they spend too much time thinking about them – they may have little insight into the fact that the belief underlying their obsession (e.g., that they will get cancer from stepping on a chemically treated lawn) is senseless, unrea-sonable, or unrealistic.

To reflect these findings, DSM-IV established a new OCD specifier, with poor insight. This specifier applies to “an indi-vidual who, for most of the time in the current episode, does not recognize that the obsessions or compulsions are excessive or unreasonable”. DSM-IV also acknowledges that the beliefs that underlie OCD obsessions can be delusional and notes that in such cases an additional diagnosis of delusional disorder or psychotic disorder not otherwise specified may be appropriate Most people with OCD are aware that other people think their symptoms are unrealistic and that the obsessions are caused by a psychiatric ill-ness. Whether insight is an important predictor of prognosis and treatment response is an intriguing issue that has received little investigation. More studies are needed to determine the effect of insight on treatment response. For example, to our knowledge no studies have assessed whether adding an antipsychotic to an SRI is more effective in patients with poor insight than in those with good insight. Studies that assess the impact of insight on compli-ance with and refusal of behavioral therapy are also needed.

Comorbidity

OCD frequently occurs in association with other Axis I dis-orders. In a study of 100 patients with primary OCD, 67 had alifetime history of major depressive disorder, and 31 had symp-toms that met criteria for current major depressive disorder (Rasmussen and Eisen, 1991). Although it may be difficult to distinguish a primary from a secondary diagnosis, some indi-viduals with OCD view their depressive symptoms as occurring secondary to the demoralization and hopelessness accompany-ing their OCD and report that they would not be depressed if they did not have OCD. However, others view their major de-pressive symptoms as occurring independently of their OCD symptoms, which may be less severe when they cycle into an episode of major depression, because they feel too apathetic to be as concerned with their obsessions and too fatigued to per-form compulsions. Conversely, OCD symptoms may intensify during depressive episodes.

Although findings have varied, the generally accepted fre-quency of tic disorders in patients with OCD is far higher than in the general population, with a rate of approximately 5 to 10% for Tourette’s disorder and 20% for any tic disorder. Conversely, pa-tients with Tourette’s disorder have a high rate of comorbid OCD, with 30 to 40% reporting obsessive–compulsive symptoms. The likelihood of childhood onset of OCD is greater in this group, and the presence of tics is associated with more severe OCD symp-toms in children. There is an increased rate of both OCD and tic disorders in the first-degree relatives of OCD probands with a family lifetime history of tics, and an increased frequency of tic disorders in the first-degree relatives of OCD probands compared with controls. There are also phenomenologic observations that link OCD and tic disorders. Individuals with both OCD and tics have several features that distinguish them from individuals with OCD alone. They more frequently have symmetry, ordering and arranging, and hoarding compulsions, and they more frequently try to attain a “just right” feeling. These data strengthen the no-tion that tic disorders and OCD are highly related. In fact, it has been suggested that tic disorders are an alternative expression or phenotype of the familial OCD subtype.

Anxiety disorders frequently coexist with OCD, with rela-tively high lifetime rates of specific phobia (22%), social phobia (18%) and panic disorder (12%) in patients with OCD (Rasmus-sen and Eisen, 1991). In one study, 17 of 100 subjects with OCD had a lifetime history of an eating disorder. Conversely, in 93 subjects with an eating disorder, 37 had symptoms that met crite-ria for comorbid OCD.

Several studies of OCD and comorbid schizophrenia found that compared with subjects with OCD alone, those with comorbid schizophrenia have a worse prognosis in terms of long-term outcome (social relations, employment, psychopathology and global functioning). Similarly, treatment studies of patients with OCD and comorbid schizotypal personality disorder have shown a poorer prognosis and poorer response to psychotropic medications for the comorbid group. Thus, it appears important to differentiate OCD plus a comorbid psychotic disorder, which may have a relatively poor outcome, from delusional OCD, which may be more similar to OCD with insight and without comorbid psychosis.

Studies of patients with schizophrenia or schizoaffective disorder have found rates of OCD ranging from 8 to 46%. This strikingly large range is most likely due to the OCD criteria used (i.e., subclinical OCD symptoms versus OCD symptoms severe enough to cause significant impairment or distress). Regardless, it is clear that a significant number of people with schizophrenia have OCD symptoms which require assessment and may benefit from treatment.

The relationship between OCD and personality disorders, particularly obsessive–compulsive personality disorder (OCPD), has received considerable attention. Early observations noted the presence of OCPD traits in patients with OCD. Systematic stud-ies have yielded inconsistent findings however. Although person-ality disorders are considered to be stable over time, one study found that of 17 OCD patients with a personality disorder, nine of the 10 treatment responders no longer met criteria for either avoidant or dependent personality disorder after successful phar-macotherapy, raising the question of whether these personality disorders actually represented a coping style in response to OCD (Ricciardi et al., 1992).