TrichotillomaniaDiagnostic FeaturesThe essential feature of Trichotillomania is the recurrent pulling out of one's own hair that results in noticeable hair loss (Criterion A). Sites of hair pulling may include any region of the body in which hair may grow (including axillary, pubic, and perirectal regions), with the most common sites being the scalp, eyebrows, and eyelashes. Hair pulling may occur in brief episodes scattered throughout the day or in less frequent but more sustained periods that can continue for hours. Stressful circumstances frequently increase hair-pulling behavior, but increased hair pulling also occurs in states of relaxation and distraction (e.g., when reading a book or watching television). An increased sense of tension is present immediately before pulling out the hair (Criterion B). For some, tension does not necessarily precede the act but is associated with attempts to resist the urge. There is gratification, pleasure, or a sense of relief when pulling out the hair (Criterion C). Some individuals experience an "itchlike" sensation in the scalp that is eased by the act of pulling hair. The diagnosis is not given if the hair pulling is better accounted for by another mental disorder (e.g., in response to a delusion or a hallucination) or is due to a general medial condition (e.g., inflammation of the skin or other dermatological conditions) (Criterion D). The disturbance must cause significant distress or impairment in social, occupational, or other important areas of functioning (Criterion E).
Associated Features and DisordersAssociated discriptive features and mental disorders. Examining the hair root, twirling it off, pulling the strand between the teeth, or trichophagia (eating hairs) may occur with Trichotillomania. Hair pulling does not usually occur in the presence of other people (except immediate family members), and social situations may be avoided. Individuals commonly deny their hair-pulling behavior and conceal or camouflage the resulgint alopecia. Some individuals have urges to pull hairs from other people and may sometimes try to find opportunities to do so surreptitiously. They may pull hairs from pets, dolls, and other fibrous materials (e.g., sweaters or carpets). Nail biting, scratching, gnawing, and excoriation may be associated with Trichotillomania. Individuals with Trichotillomania may also have Mood Disorders, Anxiety Disorders, or Mental Retardation.Associated laboratory findings. Certain histological findings are considered characteristic and may aid diagnosis when Trichotillomania is suspected and the affected individual denies symptoms. Biopsy samples from involved areas may reveal short and broken hairs. Histological examination will reveal normal and damaged follicles in the same area, as well as an increased number of catagen hairs. Some hair follicles may show signs of trauma (wrinkling of the outer root sheath). Involved follicles may be empty or may contain a deeply pigmented keratinous material. The absence of inflammation distinguishes Trichotillomania-induced alopecia from alopecia areata.
Specific Culture, Age, and Gender FeaturesAmong children with Trichotillomania, males and females are equally represented. Among adults, Trichotillomania appears to be much more common among females than among males. This may reflect the true gender ratio of the condition or it may reflect differential treatment seeking based on cultural or gender-based attitudes regarding appearance (e.g., acceptance of normative hair loss among males).
PrevalenceNo systematic data are available on the prevalence of Trichotillomania. Although Trichotillomania was previously thought to be an uncommon condition, it is now believed to occur more frequently. Recent surveys of college samples suggest that 1%-2% of students have a past or current history of Trichotillomania.
CourseTransient periods of hair pulling in early childhood may be considered a benign "habit" with a self-limiting course. However, many individuals who present with chronic Trhichtillomania in adulthood report onset in early childhood. The age at onset is usually before young adulthood, with peaks at around ages 5-8 years and age 13 years. Some individuals have continuous symptoms for decades. For others, the disorder may come and go for weeks, months, or years at a time. Sites of hair pulling may vary over time.
Differential DiagnosisOther causes of alopecia should be considered in individuals who deny hair pulling (e.g., alopecia areata, male-pattern baldness, chronic discoid lupus erythematosus, lichen planopilaris, folliculitis, decalvans, pseudopelade, and alopecia mucinosa). A separate diagnosis of Trichotillomania is not given if the behavior is better accounted for by another mental disorder (e.g., in response to a delusion or a hallucination in Schizophrenia). The repetitive hair pulling in Trichotillomania must be distinguished from a compulsion, as in Obsessive-Compulsive Disorder. In Obsessive-Compulsive Disorder, the repetitive behaviors are performed in response to an obsession, or according to rules that must be applied rigidly. An additional diagnosis of Stereotypic Movement Disorder is not made if the repetitive behavior is limited to hair pulling. The self-induced alopecia in Trichotillomania must be distinguished from Factitious Disorder With Predominantly Physical Signs and Symptoms, in which the motivation for the behavior is assuming the sick role.
Diagnostic criteria for Trichotillomania
Taken from Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, American Psychiatric Association, 1994. |