Abstract
Self-injurious behavior is a common symptom in neurodevelopmental disorders which is often the least understood and difficult to treat. In this narrative review, we intend to focus on the symptomatology, causal and risk factors for SIBs along with the nonpharmacological and pharmacological management of SIBs in NDD. A manual search was done using the electronic databases of Pubmed, Google scholar on relevant publications or cross-references till December 2022 and the data was then collated to give the prevalence, epidemiology, risk factors, treatment and management of SIB in NDD. Results showed that the behaviors begin in developmental phase and are seen in nearly 30% of children with NDD. Many SIBs become chronic over time and are characterized by being repetitive in nature, compulsive or episodic. They could be superficial or deep and are best treated by nonpharmacological methods using functional behavior assessment (FBA). Despite lack of robust evidence for psychotropics some second-generation antipsychotics have been approved for pharmacological treatment of SIB. We can conclude that until more data are available, clinicians must continue to rely upon the limited available evidence, clinical judgement, and expertise, and carefully monitored response(s) to therapy when managing SIBs in children. SIB is outcome of multiple factors that initiate and maintain the behavior. Judicious use of various groups of pharmacological agents is advised. Physician preferences, history of response and safety are part of pharmacological interventions.
Keywords
Introduction
Self-injurious behavior is a common symptom in neurodevelopmental disorders along with many other psychiatric conditions. It has been known by various names such as self-mutilatory behavior, non-suicidal self-injurious behavior or as body- focused repetitive behavior disorders.
Neurodevelopmental disorders are behavioral and cognitive disorders that arise during the developmental period that involve significant difficulties in the acquisition and execution of specific intellectual, motor, or social functions. These disorders are associated with difficulties in sensory and motor processing, and also have speech and language deficits and are seen in approximately 1%–2% of the population.1,2 They also include various genetic disorders which lead to ID and SIB like Smith-Magenis Syndrome, Lesch-Nyhan Disease, Cri du Chat Syndrome, Prader-Willi Syndrome, Pervasive Developmental Disorders, Fragile X Syndrome, Rett Syndrome, Cornelia de Lange Syndrome, and Down Syndrome. There are certain genetic theories which suggest that ASD symptoms occur due to disruption in particular genes, like the Shank 3 gene. 3
The characteristics of self-injurious behavior include that it is self-inflicted, non-lethal, non-suicidal, non-accidental act which results in tissue damage. 4 It is often repetitive and becomes chronic in children with NDD especially ASD. 5 SIB usually are seen in around 70%–80% of intellectual disabilities and they are often chronic in nature. The behaviors usually begin in the developmental phase when the child may be even 6 months old but are usually seen around 12–24 months. Several children also stop the SIBs by the time they are in primary school. Similarly, there is a prevalence of SIB in 30% of NDD6–8 and it has been seen that nearly 50% of children with ASD cease to do SIB by the time they reach secondary school or early adulthood. 9 But in many, SIB is often chronic and continues into late adulthood. 10 The difficulty in understanding the underlying etiology and pathophysiology of SIBs in children with NDDs has not been able to conclusively elucidate the reasons for the said behaviors.
The impact of SIB on the caregivers as well as the patient is tremendous and often causes a lot of socioeconomic and emotional burden, in result having a negative impact on the quality of life.1,2 Due to this, patients, caregivers and therapists are continuously trying for methods to offer relief from these behaviors. In this narrative review, we intend to focus on the symptomatology, causal and risk factors for SIBs along with the nonpharmacological and pharmacological management of SIBs in NDD.
Search Methodology
A manual search was done using the electronic databases of Pubmed, Google scholar on relevant publications or cross- references till December 2022. The search terms used were “NDD, SIB, ID, prevalence, epidemiology, risk factors, treatment, management, and neurobiology in various combinations and all those studies which seemed relevant to our topic were included, as this is a narrative review.”
Symptomatology/Phenomenology/Characteristics of SIB
Causing superficial or moderate injury to skin is the commonest form. Seen as biting, scratching, rubbing vigorously, slapping, head banging, hand or foot banging against hard surface, hair pulling, poking skin, eyes or natural orifices of body, etc.4–6 Using other physical means like – sticks or sharp objects (needles, knives, etc.), burning, using corrosive substances like cleaning material, burning, etc. Directing these self-injurious acts towards genitals or other erogenous zones is also seen occasionally. This will have implications for treatment. Picking on healing wounds and scabs.
Causes of SIB in NDD
Presently SIB is seen as final visible manifestation of various events. They can be genetic, biochemical, neurodevelopmental, psycho-social, addictive or arising out of neurodevelopmental or psychological disorders. In any individual with SIB, a detailed analysis of all these causes is necessary. It is also possible that predisposing and precipitating causes are various and additive. Hence several theorists have put forth their views on the causal relationship of SIBs in children with NDD.
The most common theory looks at the impairment in language and communication which results in social deficits and lack of ability to understand environmental stimulation. This social and environmental isolation may then lead to the development of SIBs as a means of getting attention, communication or as a means of coping with the situation and are often considered a “cry for help.”11–13
Several psychologists have put forth views that positive and negative reinforcement, escape from the activities, obtain tangibles, difficulty regulating extreme negative emotions, and relief from physical discomfort and illness and/or psychological pain are often the commonest causes why children with ASD indulge in SIBs.14,15 Sometimes, under or over-arousal caused by environmental stimuli, alteration in the pain endogenous opioid system, increased dopamine, decreased serotonin or GABA would also result in SIB. Researchers studied a group of autistic children who had low levels of calcium. Similarly, allergies, gluten sensitivity were also considered and parents of autistic children used dietary modifications to reduce these behaviors.
Other risk factors include the degree of intellectual disability especially severe and profound ID, severity of ASD, language deficits, deficiencies in social skills, adaptability, presence of hyperactivity and impulsivity, sensory and motor impairments, repetitive behaviors, sleep disturbance, etc.11–13,16 Pain conditions or underlying physical illness which causes urinary incontinence, pain, constipation, headache, etc., can worsen SIBs. 17 Similarly, inability to cope with dysmenorrhea or menstruation can trigger SIB. 18
Management of SIB
A detailed history from all possible sources like parents, siblings, caretakers, school staff and other members of mental health team can provide important information about clues, stresses, patterns of SIB. A functional analysis of such behavior is at the core of comprehensive management plan to reduce or eliminate SIB. Sometimes causes can become obvious due to detailed analysis and in many situations they remain at hypothesis level due to inadequate information or presence of multiple possible causes. Choosing most easily modifiable causes as initial target of intervention has merit of being practical.
SIB triggered by stressful events, especially physical pain or distress have clear treatment path by way of treating the precipitating cause.
Non-pharmacological Management
The following plan should be considered when considering nonpharmacological management of SIB:
Site, severity, and pattern of SIB. Intelligence, verbal and comprehension abilities of the child. Availability of support in family and helping professionals. Family’s adherence to behavior management plan. Past history of similar behavior and response to interventions.
A typical management plan will involve a common understanding of cause, remediation and each person’s/professional’s role, evaluation of response and course correction when needed.
Improving meaningful engagement in activities (alone, with a companion and in a group) for most of the awake time remains most effective intervention. Gradual introduction of self-directed solo activities and play should be early target and achievement of this goal should be generously rewarded. Early detection of distress signs (e.g., repetitive use of certain sounds/utterances, demand for attention or specific things like food, pacing and restlessness) should be given appropriate attention and planned distractions should be implemented. One has to keep and eye on the frequency of such demand over treatment period. Sometimes too early and very gratifying response itself may lead to increase in frequency of such demands. Applied Behavior Analysis (ABA) and Functional Behavior Assessment (FBA) are practically useful tools to manage SIB.
19
ABA involves observation of target behavior in terms of triggers, cues, positive and negative reinforcements. Once the therapist has analyzed how the child performs tasks, this information is used to make other tasks easier for the particular child by breaking them down into steps that will be easily understood by the child and shaped by the therapist. Applying learning from one situation to other similar situations is called generalization and it is part of ABA methodology. FBA is an application of ABA for assessment of SIBs and developing behavioral interventions that maintain their effectiveness. Verbal and material positive feedback for restful periods is often underestimated. This has a significant role in reducing SIB as part of negative attention-seeking. Negative reinforcements have limited role unless there is a clear desired and valuable thing/activity for the child that can be withdrawn to bring about stopping of SIB. Sensory exercises can help to soothe, distract, and reduce irritability.
SIB evokes complex emotions in people who witness it and help the child. Being a parent of the child adds another level of complexity to this issue. Empathic support from treating team, education about the behavior and its meaning, practical tips to reduce distress and harm are cornerstones of caretaker training. They deliver behavior interventions in real life so time spent in training them is treatment time. Encouraging them to maintain behavior and response logs helps treating team to evaluate the interventions and bring changes as needed. Independent assessment of mental health issues for parents should be offered early in the course. Supportive counselling to reduce burden and guilt is practically helpful. Help parents look at SIB as a coping strategy where child needs help instead of focusing on the behavior itself. Ignoring as well as overreacting worsens the behavior. Assist parents in dealing with their own emotions, promote help-seeking. Avoid threatening or overprotecting the child as reaction to SIB. Help parents openly express concern and desire to help.
There may arise a situation where danger to the child is severe and possibly life/limb threatening and response to all above measures is inadequate. In such situation, use of restraining may be necessary. Mental Healthcare Act 2017 gives clear guidelines for use of restraints in adults admitted at Mental HealthCare Establishment. 20 Law is mute about use in children and in situations outside MHEs. It is prudent to use restraints in lightest possible way for least time necessary. Adequate monitoring for asphyxiation, circulation, injuries should be in place and no child in restraints should be left unattended. There are innovations like K-Bands that are safer for the patient and easy to use for the caretakers. 21
Pharmacological Management
Clinicians have always been faced with a dilemma when treating SIB in cases of NDD. Majority of patients in the adult or adolescent age group who have psychiatric comorbidities like Borderline personality disorder, Impulse control or OC spectrum disorders are put on polypharmacy to achieve mood regulation and control the behavior symptoms. However, there is lack of robust evidence or clinical trials done for specifically SIB in NDD. Also, as the etiology for SIB in NDD is still to be defined the pharmacotherapy is more intended for symptom control than understanding the disease process. Hence most of the pharmacotherapeutic guidelines would be based on clinical judgement or a case-to-case approach. The difficulty in doing clinical trials is due to interpatient variability, the severity of NDD, other comorbidities, etc., which often result in the dilemma of choosing a molecule for behavior control.
Despite the low levels of evidence, pharmacotherapy is the most resorted while treating the SIBs. Most of the evidence has looked at the neurochemical basis for self- injurious behavior to identify the molecule that would help in improving the symptom.
Serotonin System
Decreased serotonin levels have been associated with impulsivity which often results in SIB. This has been strongly seen in adolescents with borderline personality disorder where risk factors like female gender, history of substance use or conduct traits, comorbid anxiety, or depression, eating disorders, childhood history of abuse, violence, etc., would result in non-suicidal self-injurious behaviors. Majority of ASD cases or ID would not be able to express due to language and social restrictions due to which serotonin as the only culprit would be difficult to establish.
Opiate System
The opiate pathway is also implicated as one of the reasons why the SIB is reinforced in children with ASD. It has been studied that children with SIB may experience the pain differently than others. 22 Some may have a reduction in pain sensitivity due to which they continue inSIB,11,12 with habituation to high levels of endogenous opioids due to repeated exposure to childhood physical or sexual abuse. Some have also proposed that SIB is due to an addiction to endogenous opioids. These theories have therefore resulted in the use of molecules which affect the pain processing mechanism like the opioid antagonists and topical anesthetic agents.
Dopamine System
Dysregulation in the dopaminergic activity has been implicated in SIB. It is responsible for impulsivity and aggression. Research has shown that dopamine antagonists have shown improvement in SIB.
While choosing a drug for reducing the SIB, every clinician should evaluate the patient for the severity of SIB, its probable cause, investigate the child’s medical history, developmental history, age of the child, look for drug-drug interactions, side effect profile, efficacy and safety data before starting any medication. The drug dose should be monitored as per the side effect profile. If the molecule does not show benefit, then the molecule should be discontinued. Several off-label drugs have been tried in SIB. Several molecules have been used as monotherapy or used in combination.
Antipsychotic Drugs
Antipsychotics especially second-generation ones have been the drugs of choice for the treatment of aggression and SIB in various NDDs with risperidone getting US FDA approval in 2006 and aripiprazole in 2009, respectively. A meta-analytic review revealed that both these drugs significantly improved the SIBs as compared to placebo. 23 However, there are no studies documenting the superiority of antipsychotics over other group of drugs. The most reported side effects with risperidone were increased weight gain, appetite and drowsiness; whereas with aripiprazole were weight gain, sedation and extrapyramidal symptoms. Therefore, in children it is very important to start with low doses and titrate very gradually.
There have been case reports and other open-label studies which have looked into the efficacy of other second- generation antipsychotics like ziprasidone, olanzapine and paliperidone24–26 for treatment of SIB in autism disorders. Though ziprasidone was found to have moderate efficacy in treating irritability and aggression in children with ASD the evidence for the same is lacking. 24
Olanzapine was primarily tried for aggressive behaviors in adults with ID. It helped in the reduction of aggression and SIB but due to its side effects of weight gain, sedation and dyslipidemia, its use in children is not preferred. 25
Paliperidone was found useful in reducing irritability in patients of ASD who did not respond to risperidone. Though paliperidone has a better side-effect profile, but the data about its efficacy in SIBs in NDDs is still inconclusive and lacking. 26
Hence, though antipsychotics are often considered as first line drugs in the treatment of self-injury, their side-effect profile is a limiting factor for children with NDD.
Antidepressant Drugs
Several SSRIs have been tried for reducing the impulsivity and aggression, depressive features seen in borderline personality disorders and have also found to be efficacious in reducing the self-injurious behavior seen in these patients.27,28 Mirtazapine an SNRI has also been used due to its action on the serotonin system to reduce the irritability/aggression, impulsivity and insomnia seen in ASDs. 29 However its impact on reducing the SIBs in ASD is not very well documented.
Mood Stabilizers/Antiepileptics
Topiramate has been found to modulate GABA and glutamate activity, thus helping in reduction of SIBs. A study reported significant reduction in skin picking in adults with Prader-Willi syndrome on a maintenance dose of topiramate of 150–200 mg/day. 30
Several other mood stabilizers like valproate, oxcarbazepine, and lamotrigine have been used to control anger outbursts/aggression and behavioral problems in ASD. None of these drugs have been specifically used to control SIBs but for the hyperactivity, impulsivity, aggression, and mood instability associated in these patients. 31 Though each of these drugs helps in controlling aggression and irritability, its use in SIBs as monotherapy is not well documented.
Clonidine
Clonidine has been used in practice for hyperarousal disorders with concomitant sleep disturbances and it acts by reducing the sympathetic outflow specifically to the prefrontal cortex. This helps in reducing the hyperarousal which may often be seen in NDD due to environmental stimulation. However, only case reports have documented the benefit of clonidine in reducing SIBs. 32
N-acetylcysteine
N-acetylcysteine (NAC), an antioxidant, inhibits glutamate release through the glutamate-cysteine antiporter. 33 As SIBs may be due to increased excitatory signaling due to the glutamatergic transmission, use of NAC may help in controlling SIBs as it reduces this signaling. However, it has not been specifically approved for SIBs.
Rilozule
Riluzole has demonstrated clinical benefits in psychiatric disorders and may be a promising treatment option in the management of SIBs. Data from a case series had demonstrated good results in ASD, moderate-to-severe intellectual disability with SIBs and/or repetitive movements. 34
Naltrexone
Naltrexone is an opioid antagonist which binds to the μ- opioid receptors. Its use in SIBs was propagated due to the theory that SIBs stimulate the release of endogenous endorphins which is responsible for the repetitive behavior. Naltrexone has been tried in adult patients but its use in SIBs in children is limited to case reports and due to its conflicting results, it is not very commonly used in NDD patients. 35
Managing SIBs in children with NDDs is a difficult task due to the refractory nature of the problem. Currently, clinicians try every treatment modality to help improve the SIBs. The caregiver burden and the treatment frustration impact the patient, family and the clinician. As there are no evidence-based guidelines, several drugs may be tried as monotherapy or in combination. It is, however, very important for the clinician to look into the history, risk factors to decide the line of management. Hence patients should be given behavioral management first and treatment should be initiated after everything has been tried. It is important to start low and go slow in drug dose titration. There has to be a continuous monitoring of side effects and improvement seen.
Conclusion
Until more data are available, clinicians must continue to rely upon the limited available evidence, clinical judgement and expertise, and carefully monitored response(s) to therapy when managing SIBs in children. SIB is outcome of multiple factors that initiate and maintain the behavior. A detailed assessment looks at biological, environmental, psychological and purely behavioral patterns as well as any interplay in these factors. Addressing the identifiable cause is first step in management. When this is not possible due to practical limitations or complexity of situation, behavioral and pharmacological remedies can be applied alone or in combination. ABA and FBA direct behavior interventions. Parent training is core component of behavior and psychological interventions. There is no single pharmacological intervention that applies to all situations. Judicious use of various groups of pharmacological agents is advised. Physician preferences, history of response and safety are part of pharmacological interventions. Physical restraints should be considered only in rare situations where harm is severe and likely to cause long-term damage.
Footnotes
Declaration of Conflicting Interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The authors received no financial support for the research, authorship, and/or publication of this article.