DSM-IV-TR Diagnostic Criteria
Recurrent pulling out of one's hair resulting in noticeable hair loss.
An increasing sense of tension immediately before pulling out the hair or when attempting to resist the behavior.
Pleasure, gratification, or relief when puling out the hair.
The disturbance is not better accounted for by another mental disorder and is not due to a general medical condition (e.g., a dermatological condition).
The disturbance causes clinically significant distress or impairment in social, occupational, or other important areas of functioning.
(Reprinted, with permission, from Diagnostic and Statistical Manual of Mental Disorders, 4th edn. Text Revision. Washington DC: American Psychiatric Association, 2000.)
The incidence of trichotillomania in the general population is unknown, but estimates have placed its prevalence in the United States as high as 8 million people. A recent survey of 2579 college freshmen indicated that 0.6% would have met criteria for trichotillomania at some point in their lifetimes. Trichotillomania appears to be more prevalent in females (although males may predominate in patients under age 6 years).
The etiology of trichotillomania is unknown; however, different theories have been proposed about the pathogenesis of this complex disorder. Psychoanalytic theory views pathologic hair pulling as a manifestation of disrupted psychosexual development, often due to pathologic family constellations. In contrast, behavioral theory conceptualizes hair pulling as a learned habit similar to nail biting or thumb sucking. Recently, a biological theory has been postulated as several researchers have proposed a serotonergic abnormality in trichotillomania and have suggested that the disorder may be a pathologic variant of species-typical grooming behaviors. Neuropsychological abnormalities, treatment response to some antidepressants, and frequent comorbidity with OCD have led to speculation regarding a neurobiological etiology, perhaps involving frontal lobe or basal ganglia dysfunction.
Family studies are suggestive of a genetic predisposition for trichotillomania but may reflect environmental learning and are inconclusive.
Patients, particularly young ones, frequently deny that they pull their hair intentionally. Others typically describe pulling their hair when alone, but they may pull it openly in front of immediate family members. These episodes tend to occur during sedentary activities such as watching television, reading, studying, lying in bed, or talking on the telephone, and they may be more frequent during periods of stress. Patients may be unaware that they are pulling their hair until they are in the middle of an episode. Some patients report being in a trance-like state when they pull their hair. These episodes may last a few minutes or a few hours. Patients may pull a few hairs or many hairs per episode. Many patients do not feel pain when the hair is pulled; some patients report that it feels good.
Patients frequently engage in oral manipulation of the hair once it is pulled including nibbling on the roots or swallowing the hair. The later behavior can lead to a rare but serious complication, a trichobezoar (hair ball) in the gastrointestinal tract. The consequences of a trichobezoar can be life-threatening: obstruction, bleeding, perforation, pancreatitis, and obstructive jaundice.
Patients typically pull hair from their scalp, causing diffuse hair thinning or virtual baldness. The typical patient demonstrates patchy areas of alopecia without inflammation that spare the periphery. Many patients are adapt at hiding areas of hair loss by judicious hair styling, but may ultimately resort to hairpieces and wigs when the areas become too large or too numerous to hide. Patients may also pull hair from other parts of their body, including eyelashes, eyebrows, pubic region, or from face, trunk, extremities, or underarms.
Psychological Testing & Laboratory Findings
Although psychological testing may not be useful in confirming a diagnosis of trichotillomania, a punch biopsy may be of some help in this regard. The biopsy results typically reveal increased catagen hairs along with melanin pigment casts and granules in the upper follicles and infundibulum.
According to DSM-IV-TR diagnostic criteria, a diagnosis of trichotillomania is not warranted if the condition can be better accounted for by another mental disorder or is due to a general medical condition. For example, if a patient has another significant Axis I psychiatric disorder (e.g., a condition with delusions or hallucinations) that might account for the hair pulling, then the diagnosis of trichotillomania would not be warranted. When patients deny that they pull their hair intentionally, dermatologic consultation may be required to rule out other causes of hair loss. Most notable among these conditions is alopecia areata, but tinea capitis, traction alopecia, androgenic alopecia, monilethrix, and other dermatologic conditions should also be considered. A punch biopsy may be indicated particularly when one of these disorders is suspected.
An initial double-blind cross-over trial compared clomipramine to desipramine in 13 patients with trichotillomania screened to rule out neurologic disorder, mental retardation, primary affective disorder, psychosis, and OCD. Clomipramine produced improvement in clinical symptoms (33–53% reduction in severity scores) on each of three rating scales designed to assess trichotillomania symptomatology and clinical improvement; scores on two of the three scales were statistically significant. Two subsequent placebo-controlled, double-blind cross-over studies failed to show efficacy for fluoxetine.
Little rigorous research has been conducted concerning the differential effectiveness of treatments for trichotillomania. Clomipramine and behavior therapy probably constitute the current treatments of choice, but this conclusion is tempered by the paucity of treatment outcome studies. Habit renewal training is the most effective form of behavioral therapy. Trichotillomania occurs with variable levels of severity in terms of hair pulling and comorbid psychopathology. As a result, response to treatment is highly variable and rather unpredictable.
Complications/Adverse Outcomes of Treatment
Although hair loss is self-induced, patients are often particularly sensitive to comments about their appearance and go to great lengths to hide their disfigurement. These patients are often fearful that their shameful “secret” will be discovered and that they will be ridiculed in public. If the disorder is protracted, the patient's self-esteem can suffer drastically. Some individuals develop avoidant behavior and become socially withdrawn in order to avoid exposure. Trichobezoar is a rare complication. Little is known about the comorbidity of trichotillomania. Aside from the possibility that the disorder may be related to anxiety or mood disorder, there has been much speculation that it is a variant of OCD. Some research lends support to this hypothesis; however, the studies that failed to show efficacy for fluoxetine would argue against such a relationship.
Trichotillomania in preadolescents (particularly in those younger than 6 years of age) is thought to be associated with little psychopathology. In adolescent and adult patients, however, an association with other mental disorders has been demonstrated. In a study of 60 adult chronic hair-pullers (50 of whom met strict criteria for trichotillomania), only 18% did not demonstrate a current or past diagnosis of an Axis I psychiatric disorder other than trichotillomania. The lifetime prevalence of mood disorders was 65%, and 23% met criteria for current major depressive episode. Lifetime prevalence of anxiety disorders was 57%, and 10% demonstrated a current diagnosis of OCD and 5% a history of OCD. Another 18% endorsed present or past obsessions and compulsions not meeting the full criteria for OCD. Lifetime prevalence of panic disorder with or without agoraphobia was 18%, generalized anxiety disorder 27%, simple phobia 32%, eating disorder 20%, and substance abuse disorder 22%.
A smaller study that used standardized assessment techniques found that 45% of the trichotillomania patients studied met criteria for current or past major depression, 45% had generalized anxiety disorder, 10% had panic disorder, and 35% had alcohol or substance abuse. Unfortunately, patients with OCD were excluded from the study.
Adverse outcomes of treatment are limited to the usual side effects experienced with clomipramine or other antidepressants.
Although there might be adverse consequences of psychodynamic psychotherapy or a behavioral treatment approach, such adverse outcomes are generally thought to be rare and unpredictable.
The prognosis and course of illness generally can be predicted from the age at onset. Trichotillomania begins most often in childhood or young adolescence. Hair pulling in very young children is frequently mild and remits spontaneously. Patients with a later age at onset tend to have more severe symptoms that run a chronic course. These patients are thought to have a higher incidence of comorbid anxiety and depressive disorders.
Keuthen NJ, O'Sullivan RL, Goodchild P, et al.: Retrospective review of treatment outcome for 63 patients with trichotillomania. Am J Psychiatry
Minichiello WE, O'Sullivan RL, Osgood-Hynes D, et al.: Trichotillomania: Clinical aspects and treatment strategies. Harv Rev Psychiatry