The essential feature of trichotillomania is the recurrent failure to resist impulses to pull out one’s own hair. Resulting hair loss may range in severity from mild (hair loss may be negligible) to severe (complete baldness and involving multiple sites on the scalp or body). Individuals with this condition do not want to en-gage in the behavior, but attempts to resist the urge result in great tension. Thus, hair-pulling is motivated by a desire to reduce this dysphoric state. In some cases, the hair-pulling results in a plea-surable sensation, in addition to the relief of tension. Tension may precede the act or may occur when attempting to stop. Distress over the symptom and the resultant hair loss may be severe.
The etiology of trichotillomania is unknown. The phenom-enological similarities between trichotillomania and OCD have prompted speculations that the pathophysiology of the two con-ditions may be related. The apparent association between altered serotonergic function and OCD has guided attention toward the possible role of serotonergic function in the underlying cause of trichotillomania. Thus, interest has been spurred in examining serotonergic function in patients with trichotillomania. As yet, however, only limited laboratory investigations have emerged.
In summary, few data are available to support any particu-lar model of the etiological pathophysiology of trichotillomania. Early studies point to some alteration of brain activity. Incon-sistent support has been found in these early explorations for a relationship with OCD.
Typically, the person complaining of unwanted hair-pulling is a young adult or the parent of a child who has been seen pull-ing out hair. Hair-pulling tends to occur in small bursts that may last minutes to hours. Such episodes may occur once or many times each day. Hairs are pulled out individually and may be pulled out rapidly and indiscriminately. Often, however, the hand of the individual may roam the afflicted area of scalp or body, searching for a shaft of hair that may feel particularly coarse or thick. Satisfaction with having pulled out a complete hair (shaft and root) is frequently expressed. Occasionally the experience of hair-pulling is described as quite pleasurable. Some individuals experience an itch-like sensation in the scalp that is eased by the act of pulling. The person may then toss away the hair shaft or inspect it. A substantial number of people then chew or consume (trichophagia) the hair. Hair-pulling is most commonly limited to the eyebrows and eyelashes. The scalp is the next most frequently afflicted site. However, hairs in any location of the body may be the focus of hair-pulling urges, including facial, axillary, chest, pubic and even perineal hairs.
Anxiety is almost always associated with the act of hair-pulling. Such anxiety may occur in advance of the hair-pulling behavior. A state of tension may occur spontaneously, driving the person to pull out hair in an attempt to reduce dysphoric feel-ings. Varying lengths of time must pass before the tension abates. Consequently, the amount of hair that may be extracted in an epi-sode varies from episode to episode and from person to person. Frequently, hair-pulling begins automatically and without con-scious awareness. In such circumstances, individuals discover themselves pulling out hairs after some have already been pulled out. In these situations, dysphoric tension is associated with the attempt to stop the behavior.
Circumstances that seem to predispose to episodes of hair-pulling include both states of stress and, paradoxically, mo-ments of particular relaxation. Frequently hair-pulling occurswhen at-risk individuals are engaged in a relaxing activity that promotes distraction and ease (e.g., watching television, reading, talking on the phone). It is common for hair-pullers to report that the behavior does not occur in the presence of other people. A frequent exception may be that many pull hair in the presence of members of the nuclear family.
Some individuals have urges to pull hairs from other peo-ple and may sometimes try to find opportunities to do so surrepti-tiously (such as initiating bouts of play fighting). There have been reports of affected individuals pulling hairs from pets, dolls, and other fibrous materials, such as sweaters or carpets.
The distress that usually accompanies trichotillomania varies in severity. Concerns tend to focus on the social and vo-cational consequences of the behavior. Themes of worry include fear of exposure, a feeling that “something is wrong with me”, anxiety about intimate relationships and sometimes inability to pursue a vocation. Because certain kinds of work, such as read-ing and writing at a desk, seem to precipitate episodes of hair-pulling, some afflicted individuals make career choices based on the avoidance of desk work. Leisure activities that may involve a risk of exposure (ranging from gymnastics class to sexual inti-macy) may be avoided.
Patterns of hair-pulling behavior among children are less well described. Usually, the parent observes a child pulling out hair and may note patches of hair loss. Children may sometimes be unaware of the behavior or may, at times, deny it. Childhood trichotillomania has been reported to be frequently associated with thumb-sucking or nail-biting. It has been suggested that trichotillomania with onset in early childhood may occur frequently with spontaneous remissions. Consequently, some have recommended that trichotillomania in early childhood may be considered a benign habit with a self-limited course. However, many individuals who present with chronic trichotillomania in adulthood report onset in early childhood.
In general, the diagnosis of trichotillomania is not complicated. The essential symptom – recurrently pulling out hair in response to unwanted urges – is easily described by the patient. When the patient acknowledges the hair-pulling behavior and areas of patchy hair loss are evident, the diagnosis is not usually in doubt. Problems in diagnosis may arise when the diagnosis is suspected but the patient denies it. Such denial may occur in younger in-dividuals and some adults. When the problem is suspected but denied by the patient, a skin biopsy from the affected area may aid in making the diagnosis.
The psychiatrist should carefully inquire into the nature of the distress and concerns that may be present in a person with this problem. Although the cosmetic impact may appear slight, dis-tress may be severe. Concerns about disclosure, anticipation of social rejection and concerns about limitations in career choices are frequent and may result in chronic dysphoria. The psychia-trist should be aware of the embarrassment that may accompany inspection of the hair loss, particularly when located in regions of the body that are not usually accessible in the course of a standard psychiatric examination. Because of the apparent fre-quency of comorbid mood disorders (past or current), the in-terviewer should pay special attention to the presence of these features.
Areas of hair loss can be marked by complete alopecia or can appear diffusely thinned or “ratty”. Altered scalp appearance can range from small areas of thinned hair to complete baldness. For unclear reasons, several patterns of scalp loss are typical. Fre-quently, coin-sized areas of alopecia are noted at the vertex or at temporal or occipital regions. Among more severely afflicted people a peculiar pattern, so-called tonsure trichotillomania, may appear: a completely bald head except for a narrow, circular fringe circumscribing the outer boundary of the scalp, producing a look reminiscent of medieval friars.
Despite the hair loss, most individuals with this condition have no overtly unusual appearance on cursory inspection. If the hair loss is not covered by clothing or accessories, artful comb-ing of hair or use of eyeliner and false eyelashes may easily hide it. The ease with which the condition may often be hidden may explain the general underappreciation of its apparent frequency and potential associated distress.
Histological findings are considered characteristic and may aid diagnosis when it is suspected despite denial by the individual. Biopsy samples from involved areas may have the following features. Short and broken hairs are present. The surface of the scalp usually shows no evidence of excoriation. On histological examination, normal and damaged follicles are found in the same area, as well as an increased number of catagen (i.e., nongrow-ing) hairs. Inflammation is usually minimal or absent. Some hair follicles may show signs of trauma (wrinkling of the outer root sheath). Involved follicles may be empty or contain a deeply pig-mented keratinous material. The absence of inflammation distin-guishes trichotillomania-induced alopecia from alopecia areata, the principal condition in the differential diagnosis.
Secondary avoidance of intimate relationships, which occurs among some individuals with trichotillomania, may be exac-erbated for women in cultures in which physical appearance is weighted differently for men and women. Avoidance of sports activities, in which disguised hair loss can be revealed, may also have gender-related effects in cultures in which athletic participation has different social meanings for men and women. Although culture-based expectations regarding appearance may make hair loss a greater burden for women, women may have a greater opportunity to hide hair loss through the use of wigs, hats and scarves. Reliable data regarding sex ratio in the general population are not yet available. For many women hair-pulling may worsen during the premenstrual phase.
Among individuals presenting with alopecia who complain of hair-pulling urges, the diagnosis is not usually in doubt. When patients deny hair-pulling, other (dermatological) causes of alopecia should be considered. These include alopecia bareata, male pattern hair loss, chronic discoid lupus erythematosus, li-chen planopilaris, folliculitis decalvans, pseudopelade and alo-pecia mucinosa.
Trichotillomania is not diagnosed when hair-pulling oc-curs in response to a delusion or hallucination. Many peopletwist and play with their hair. This may be exacerbated in states of heightened anxiety but does not qualify for a diagnosis of trichotillomania.
Some individuals may present with features of tricho-tillomania but hair damage may be so slight as to be virtually undetectable, even under close examination. In such conditions the disorder should be diagnosed only if it results in significant distress to the individual. Trichotillomania may have a short, self-limited course among children and may be considered a tem-porary habit. Therefore, among children the diagnosis should be reserved for situations in which the behavior has persisted during several months.
Trichotillomania was long thought to be an uncommon condition, often accompanied by other psychiatric conditions. Although de-finitive studies of frequency rates in the general population are still lacking, three surveys of college-age samples support the emerging view that trichotillomania is quite common. In two of these samples, totaling approximately 3000 undergraduate students, a lifetime incidence of self-identified trichotillomania (reaching full symptom criteria as described in DSM-III-R) was present in about 1% of the respondents. Some features of the con-dition – but not meeting full criteria – were identified in an ad-ditional 1 to 2% (Rothbaum et al., 1993).
In addition, because onset may occur later in life than the mean ages of individuals in these groups, the true lifetime inci-dence would probably be higher. Moreover, these samples consist of a selected population – largely first-year college students – and may not reflect the general population. Nonetheless, these stud-ies indicate that the condition is likely to be far more common than previously assumed. But definitive, controlled studies of the prevalence of the condition have not yet been performed.
Individuals with trichotillomania have increased risk for mood disorders (major depressive disorder, dysthymic disorder) and anxiety symptoms. The frequency of specific anxiety disorders (such as generalized anxiety disorder and panic).