Obsessive–Compulsive Personality Disorder
OCPD is an Axis II disorder that has a name that sounds similar to OCD but is associated with meticulousness, persistence, rigidity, and personal isolation. As noted earlier in this chapter, only a small minority of OCD patients have concurrent OCPD. This confusion may relate historically to Sigmund Freuds characterization of obsessions and compulsions in his work with the "Rat Man." Unfortunately, the Rat Man had both OCD and OCPD, leading Freud to entangle the two entities in his interpretations. The key difference between elements of OCPD and OCD is the ego-syntonic nature of the experiences and behavior in OCPD. There is no dread but rather a desire that others conform to the individuals standards or desires.
Specific phobias involve excessive fears of specific situations or circumstances. They often involve fears of situations that others might experience as mildly aversive or anxiety provoking (e.g., contact with snakes or spiders), but the phobic individual has an excessive reaction to those circumstances. Avoidance is prominent and effective in allaying anxiety. In OCD, fears can be situation specific; however, there is usually a sense of doubt or uncertainty associated with the dread (e.g., uncertainty whether germs are present), as the individual cannot be certain he or she has successfully avoided the aversive circumstance. No rituals are involved in simple phobias.
Hypochondriasis is an unreasonable, persistent concern that something is wrong with the body. It can lead to repeated requests for medical care or reassurance. Hypochondriasis can mimic the obsessions of OCD; however, hypochondriacal concerns are limited to the body, and there are no other obsessions and compulsions. The individual is usually not delusional and may recognize that the behavior is excessive. Patients with hypochondriasis usually lack the sense of immediacy that exists in OCD. The individual experiences worries about long-term health rather than short-term immediate dread. Hypochondriasis can be associated with abnormal somatic perceptions, which are unusual in OCD.
Body Dysmorphic Disorder
Body dysmorphic disorder (BDD) involves the unreasonable sense that something about the body is malformed, inadequate, or offensive to others. The individual may spend excessive time looking at, or seeking medical or surgical treatment for the affected area. BDD differs from OCD in the degree of insight, as the individual with BDD truly believes that the body area is abnormal. There is no sense of incompletion or dread that something terrible will happen. The driven behaviors associated with BDD involve corrective measures to hide or alter an imagined defect and are not carried out with a sense that something has not been completed. The distinction between BDD and OCD can be difficult when the individual experiences "just-right" perceptions related to the body or when the individual has a fear of having an offensive body odor. In such cases the diagnosis of OCD may be warranted.
Trichotillomania is characterized by urges to pull hairs from the body. The hair is most frequently pulled out singly, and the act of pulling is associated with an experience of pleasure or a release of tension. Binges of hair pulling result in large bald patches. Trichotillomania differs from OCD in that the former involves no obsessions, and the behavior is rewarding.
Pathologic skin-picking can occur as an unconscious habit or as a response to an exaggerated concern about the texture of the skin. The individual may be drawn to the behavior by an attractive process that is hard to overcome. Skin-pickers are typically aware that what they are doing is destructive; however, they are unable to overcome the desire to carry out the behavior. Such picking is similar to trichotillomania in this regard. It differs from OCD in that in pathologic skin-picking there is no sense of dread, uncertainty, or incompletion, and the behavior is not carried out to prevent something bad from happening. It also differs from OCD in that pathologic skin-picking has a self-destructive or mutilative component that is rarely seen in uncomplicated OCD.
Anorexia nervosa involves an excessive concern with body image, accompanied by a refusal to eat, with purposeful behavior directed at maintaining a low body weight. In anorexia nervosa, there is a delusional perception that the body is overweight. Unlike in OCD, the anorexic individual has no insight regarding this concern. Feelings of dread, uncertainty, or incompletion are absent or are not prominent. Driven behaviors are performed with the intention of maintaining or exacerbating a desired condition. Although hoarding may be observed, no true compulsions are associated with the primary illness. Individuals with OCD can experience significant weight loss in conjunction with fears associated with food contamination. These individuals, however, do not typically have concerns about their body image and often acknowledge the absurdity of their condition.