Revisiting repetitive behaviors: A case series on compulsive sexual behavior disorder, trichotillomania, non-suicidal self-injury, and binge eating disorder

Abstract

Compulsive sexual behavior disorder (CSBD), trichotillomania (TTM), binge eating disorder (BED), and non-suicidal self-injury (NSSI) are classified in separate categories in the International Classification of Diseases, 11^th Revision (ICD-11). This case series aims to explore these disorders’ overlapping impulsive and compulsive features despite their shared phenomenology and comorbidity. It also discusses the insight, reward mechanisms, and associated neurobiological understanding of repetitive behaviors. In the end, it also highlights the potential role of glutamatergic medications in their treatment. Further research is warranted to explore the glutamatergic system’s involvement and assess the efficacy of glutamate modulators across the impulsive-compulsive spectrum.

Compulsive sexual behavior disorder (CSBD) is classified under impulse control disorders; trichotillomania (TTM), on the other hand, is moved from impulse control disorder (ID) to obsessive-compulsive and related disorders (OCRD) in the International Classification of Diseases, 11^th Revision (ICD-11).[1] Binge eating disorder (BED) is classified under eating disorders, whereas non-suicidal self-injury (NSSI) is categorized under mental or behavioral symptoms, signs, or clinical findings in ICD-11. In ICD-11, TTM predominantly reflects its repetitive behavior patterns and difficulty controlling behavior. In contrast, CSBD is predominantly considered to have a persistent pattern of failing to control intense, repetitive sexual urges, and behaviors, leading to significant distress or impairment. Impulse dyscontrol refers to a quick response to internal or external stimuli without forethought, often disregarding the potential negative consequences for oneself or others. At the same time, compulsions are repetitive actions performed to reduce intrusive and ego-dystonic urges.[2] Even though the “compulsive” word is included, sexual behavior in CSBD is considered under ID. In contrast, patients often recognize the presentation of TTM as impulsive, overt, and associated with negative reinforcement, but we all know that TTM has moved to OCRD in ICD-11. The repetitive nature of BED and NSSI, often comorbid with OCRD and ID, is well known.[3,4] All of them can vary in insight and reinforcement mechanisms. Therefore, there is a need to look at repetitive behavior that shares impulsive and compulsive phenomena with a significant overlap between pharmacotherapy and psychotherapy principles.[5,6,7] This case series illuminates the novel approach to look at repetitive behaviors shared by multiple such disorders in different categories in ICD-11 and brushes upon the neurobiological underpinnings with treatment implications.[8] Written informed consent was obtained to report clinical characteristics and photographs from all three cases.

CASE SERIES

Case-1

A 20-year-old male presenting with a three-year history of obsessive-compulsive symptoms, predominantly fear of hand-contamination, followed by washing compulsions, later accompanied by pleasurable sexual urges toward same-sex. The acting out behaviors on sexual urges, such as following a stranger adolescent, led to significant interpersonal conflicts involving both families. The obsessive thoughts of contamination were persistent, recurrent, intrusive, and ego-dystonic, causing distress and interfering with his daily functioning. At the same time, his sexual urges toward same-sex were reported to be persistent, recurrent, intrusive, ego-syntonic, and pleasurable, resulting in watching, stalking, and following the stranger. Nothing suggestive of the false belief that the stranger was in love with him. Although it was confined to a single individual, the behavior nonetheless created considerable dysfunction and interpersonal issues associated with the inability to resist while watching, stalking, and talking to a stranger, necessitating therapeutic intervention. After outpatient evaluation, he was admitted to the psychiatry ward for 20 days, during which intensive monitoring and assessments on the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS)[9] and Brown Assessment of Beliefs Scale – Adult Version (BABS)[10] reflected a score of 32 and 0, respectively. He was started on Fluoxetine 20 mg per day and increased to 60 mg daily for contamination-related OCD. Naltrexone 50 mg daily was added to manage more disabling sexual urges, considering it to be impulsive. Following discharge, he was engaged in outpatient cognitive behavior therapy (CBT) for over six months, along with the above medications. His obsession with contamination and washing compulsion reduced (Y-BOCS = 6) at the end of 6 months. However, the sexual urges were consistently reported as being pleasurable, involving same-sex adolescents, and continued to disrupt psychosocial functioning. We added N-acetyl cysteine (NAC) at 1200 mg daily to target the complex nature of sexual urges, which were considered to be part of CSBD. We noted a moderate to mild reduction in the intensity and frequency of sexual urges in the next 3 months on clinical global impression severity (from 6 to 4). In addition to pharmacotherapy, he also underwent CBT, with a focus on managing obsessive thoughts, understanding boundaries, and improving interpersonal relationships. Laboratory investigations for CSBD were conducted, which showed that luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, prolactin, liver function tests (LFTs), and renal function tests (RFTs) were within normal range. The patient’s compulsive and impulsive behavior required a diagnosis of OCRD and CSBD with a comprehensive treatment plan.

Case-2

A 20-year-old female presented with noticeable bald patches across her scalp, eventually extending to involve the entire scalp area [Figure 1]. She was referred to psychiatry from the Department of Dermatology. She presented with recurrent, irresistible urges to pull out her hair, leading to visible hair loss and significant distress. This behavior has impacted her self-esteem and daily functioning. She was diagnosed with trichotillomania by a psychiatrist. Her treatment regimen included gradual titration of Escitalopram to 20 mg per day, prescribed to help manage underlying anxiety and reduce the repetitive urges to pull the hair. NAC 1200 mg per day was added, which has been shown to reduce impulsive behaviors by modulating glutamate levels. Additionally, she was engaged in habit reversal therapy, a specialized form of CBT that helped her become more aware of the urges and trained her to adopt alternative, non-destructive behaviors in response to these impulses. She also reported in her subsequent visits regarding the obsessive nature of thought of contamination followed by compulsive washing, which was subsyndromal, without distress or dysfunction. She did not warrant the diagnosis of OCD. However, her TTM was better regarding treatment response with a reduction in the Yale Global Tic Severity Scale (YGTSS)[11] from 23 to 16.

Figure 1.

Shows the bald patches resulting from trichotillomania

Case-3

A 32-year-old woman with a five-year history of anger dyscontrol associated with recurrent intrusive thoughts of self-harm, accompanied by uncontrolled eating behaviors, sought psychiatric evaluation. A detailed assessment revealed that impulsive episodes of binge eating often occur through mobile applications for online food delivery, loss of control while eating, and vomiting episodes due to feeling uncomfortably full. Her weight was 98 kilograms, and her body mass index was 32. Over the past two years, she was treated for repetitive counting behaviors in response to pathological doubts about her safety, indicative of OCD with BED. Additionally, she experienced NSSI urges, repetitive in nature, finding a paradoxical sense of relief and pleasure when inflicting superficial wounds with sharp objects (without intention to die and use of non-violent methods), despite recognizing the behavior’s distressing nature and its impact on her family. There was nothing suggestive of personality disorder during the evaluation. The patient responded well to a treatment regimen, including NAC 600 mg twice a day, lamotrigine 150 mg per day, and Fluoxetine 40 mg per day. An additional diagnosis of NSSI was considered. Her behaviors were assessed on Y-BOCS with a score reduction from 28 to 12 in three months. She was also treated with supportive psychotherapy for NSSI behavior.

DISCUSSION

All the disorders under consideration here, such as TTM, CSBD, NSSI, and BED, involve repetitive behaviors intended to reduce distress but are classified in different categories in ICD-11. All the disorders exhibit repetitive behaviors maintained through positive or negative reinforcement, where actions are repeated to experience pleasure or escape negative emotions despite adverse outcomes, depending on the insight into behavior.

In TTM, individuals experience an urge to pull hair, leading to temporary relief but often poor awareness of the intended harm. In CSBD, sexual activities are perceived as compulsive and pleasurable, with positive reinforcement encouraging repetition, as seen in our case.[12] Critics argue that classifying CSBD based solely on symptoms can be misleading.[13] Determining the appropriate treatment and the placement of such behaviors in ICD-11, considering their impulsive-compulsive nature and comorbidity with each other, requires further exploration.[3,14,15,16,17,18] So far, in the literature, proposed specifiers for body-focused repetitive behaviors (BFRBs) include- awareness, trichophagia (hair ingestion), and skin infection. The other objective measure, the Generic BFRB Scale (GBS-8),[19] proposed dimensions such as frequency, intensity, control, emotional distress, and physical damage. We propose the inclusion of impulse dysregulation and compulsivity as dimensions while insight and reinforcement as specifiers, as shown in Table 1, for most repetitive behaviors that share overlapping phenomenology.[20]

Table 1.

A dimensional approach to the impulsive-compulsive spectrum depicts a group of disorders with repetitive behaviors based on impulsivity, compulsivity, insight, and reinforcement pattern

Group	Disorders	Impulsive-compulsive spectrum disorder
		Dimension		Specifier
		Impulse dysregulation	Compulsive behavior	Insight	Reinforcement/reward pattern
Currently, obsessive-compulsive and related disorders	Obsessive-compulsive disorder (OCD)	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Body dysmorphic disorder	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Hoarding disorder	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Trichotillomania	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Excoriation disorder	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Olfactory reference syndrome	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Hypochondriasis	High/low	Overt/Covert	Fair/poor	Positive/Negative
Currently, Impulse control disorder	Intermittent explosive disorder	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Kleptomania	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Pyromania	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Compulsive sexual behavior disorder	High/low	Overt/Covert	Fair/poor	Positive/Negative
Other potential disorders under consideration from a dimensional perspective, with a specifier due to the impulsive-compulsive spectrum	Gambling disorder	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Gaming disorder	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Eating disorders	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Paraphilic disorders	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Non-suicidal self-injurious behavior (NSSIB)	High/low	Overt/Covert	Fair/poor	Positive/Negative
	Bodily distress disorder	High/low	Overt/Covert	Fair/poor	Positive/Negative

From a neurobiological standpoint, dysregulated glutamate signaling in the brain’s reward system is crucial in impulsive and compulsive behaviors as noted in our case series.[21] Compulsivity involves difficulty stopping an action, while impulsivity relates to problems starting actions.[22] CSBD TTM, NSSI, and BED are linked to dysfunction in the prefrontal cortex (PFC); the compulsive component shows PFC overactivity, whereas the impulsive component shows underactivity. This may differ from the overactive orbitofrontal-subcortical loops seen in typical OCD.[2,23] NAC is a cysteine pro-drug that works as a glutamatergic agent and an anti-oxidant. It restores extracellular glutamate levels in the nucleus accumbens, the primary functional pathway for reinforcement and reward mechanisms in repetitive behaviors.[24] As noted in our cases, it might have shown its efficacy in impulsive and compulsive behaviors.

The ICD-11 groups, such as TTM, CSBD, NSSI, and BED, are separately categorized despite overlapping features of impulsivity, compulsivity, and reinforcement mechanisms.[4] The symptoms of CSBD with OCD, TTM with OCD, and NSSI with BED often co-occur, as reported in our cases.[3,15,17,18] While many individuals with OCD typically have good insight into the irrationality of their behaviors, those with CSBD, TTM, NSSI, and BED differ in levels of insight, reinforcement patterns, and impulsive and compulsive components. Frequent comorbidity of such repetitive behaviors with mood instability and self-harm ideas probably shares common neurobiology that perhaps responds to glutamatergic agents such as NAC.[14,18]

CONCLUSIONS:

This case series supports the existing evidence of shared phenomenology and comorbidity across repetitive behaviors and elucidates how including the dimensions of impulse dysregulation and compulsive behavior, specifiers for insight and reinforcement, could imply future classificatory systems. Despite their categorical phenotypes, the case series also recognizes the importance of glutamatergic medications in repetitive behaviors. Despite slight differences in presentation phenotypes, the evidence for shared comorbidities, neurobiology, and phenomenology requires further research to explore the role of the glutamatergic system in CSBD, TTM, NSSI, and BED. Future studies should be directed to understand the spectrum of impulsive-compulsive disorders rather than subtypes and justify the role of glutamate modulators in them.

Authors’ contributions

All authors contributed equally to compilation of clinical case details, manuscript writing, critical analysis of literature and discussion.

Ethical statement

Not applicable.

Data availability statement

Not applicable.

Patients' consent

Informed consent was taken from patients before publication.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understands that her name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.