The use of clozapine among individuals with intellectual disability: a review

Clozapine for persons with neurodevelopmental disorders: a systematic review and expert recommendations for clinical practice

INTRODUCTION

We aimed to synthesize the information on the risks and benefits of clozapine prescription for resistant challenging behavior in persons with neurodevelopmental disorders.

METHODS

Articles were identified with MEDLINE, Web of Sciences, and PsycINFO search from inception through January 2024. The review was restricted to persons with intellectual disability (ID) and/or autism spectrum disorder (ASD) without comorbid psychotic or affective disorder. Data were synthesized narratively.

RESULTS

We identified 24 articles (13 case reports, eight chart studies, two controlled studies, one pharmaco-epidemiological study) including 296 patients with ID (n = 222) or ASD (n = 74) (10% aged ≤ 18 years). After clozapine initiation, a decreased frequency of challenging behavior persisting over time was reported in most participants included in clinical studies, and a significant reduction in the number of admissions in the population-based two-year mirror-image study. Adverse drug reactions were those commonly observed with clozapine, i.e. constipation, sedation, and weight gain.

CONCLUSIONS

Since only four participants were included in the controlled studies, the benefits of clozapine in neurodevelopmental disorders are supported by a body of evidence exclusively drawn from observational studies. Further studies are required to clarify the indications of clozapine with respect to the unmet need induced by resistant challenging behavior.

REGISTRATION

PROSPERO database registration number CRD42024522343.

Healthcare practitioners' views and experiences of barriers and facilitators to weight management interventions for adults with intellectual disabilities

BACKGROUND

Obesity is common in adults with intellectual disabilities, yet little is known about how weight management interventions are provided for this population.

METHODS

Semi-structured interviews were held with 14 healthcare practitioners involved in weight management interventions in an English county. A study topic guide was developed to elicit practitioners' views and experiences of barriers and facilitators to weight management for adults with intellectual disabilities. Responses were analysed using thematic analysis.

RESULTS

Several barriers are involved in weight management for people with intellectual disabilities including communication challenges, general practitioners' lack of knowledge and awareness of weight management services, inconsistencies in caring support, resource constraints, wider external circumstances surrounding the individuals and motivational issues. Facilitators include reasonable adjustments to existing weight management services. However, there is a need for specialist weight management provision for people with intellectual disabilities.

CONCLUSIONS

This study provides suggestions for future research, policy and practice consideration.

Real-world effectiveness of clozapine for intellectual disability: Results from a mirror-image and a reverse-mirror-image study

BACKGROUND

Comorbid mental illness is common in patients with intellectual disability. Antipsychotics are widely used for these conditions, but the effect of clozapine remains largely unknown.

AIMS

We aimed to investigate the effectiveness of clozapine on naturalistic outcomes in patients with intellectual disability.

METHODS

By combining the national health registers, we identified all patients in Denmark with intellectual disability initiating clozapine treatment during the period 1996-2012. We used a mirror-image model to test whether initiation of clozapine treatment was associated with reduction in psychiatric admissions and inpatient days, reduction in the number of individuals performing intentional self-harm or overdose, and less frequent use of concomitant psychopharmacological treatment. Similar outcome measures were used in a reverse mirror-image model to investigate the effects of clozapine termination.

RESULTS

A total of 405 patients with intellectual disability redeemed clozapine. After initiation of clozapine the number of psychiatric admissions were reduced by 0.65 admissions (95% CI: 0.31-1.00) and the inpatient days were reduced by 67.2 days (95% CI: 51.2-83.3), with a similar decrease for patients with intellectual disability without psychiatric comorbidity. Clozapine treatment was not found to reduce the number of individuals with intentional self-harm, incidents of overdose, or the use of concomitant psychotropics. In cases where clozapine treatment was terminated, the number of psychiatric admissions increased by 0.57 admissions (95% CI: 0.01-1.12).

CONCLUSION

This nationwide study, which is the largest to date, suggests that treatment with clozapine is associated with a reduction in psychiatric admissions and inpatient days in patients with intellectual disability. Further studies evaluating the effects of clozapine in patients with intellectual disability are warranted.

Clozapine for psychotic disorders in adults with intellectual disabilities

BACKGROUND

Psychosis is three times more common in people with an intellectual disability than in those without an intellectual disability. A low intelligence quotient (IQ) is a defining characteristic for intellectual disability and a risk factor for poor outcome in psychosis. Clozapine is recommended for treatment-resistant psychosis. The effect of psychotropic medication can be different in people with intellectual disability; for example, they may be more prone to side effects. People with an intellectual disability and psychosis form a special subgroup and we wanted to examine if there is randomised controlled trial (RCT) data in this population to support the use of clozapine.

OBJECTIVES

To determine the effects of clozapine for treating adults with a dual diagnosis of intellectual disability and psychosis.

SEARCH METHODS

We searched CENTRAL, Ovid MEDLINE, Embase and eight other databases up to December 2014. We also searched two trials registers, the Cochrane Schizophrenia Group's Register of Trials, and contacted the manufacturers of clozapine.

SELECTION CRITERIA

RCTs that assessed the effects of clozapine, at any dose, for treating adults (aged 18 years and over) with a dual diagnosis of intellectual disability and psychotic disorder, compared with placebo or another antipsychotic medication.

DATA COLLECTION AND ANALYSIS

Three review authors independently screened all titles, abstracts and any relevant full-text reports against the inclusion criteria.

MAIN RESULTS

Of the 1224 titles and abstracts screened, we shortlisted 38 full-text articles, which we subsequently excluded as they did not meet the inclusion criteria. These studies were not RCTs. Consequently, no studies are included in this Cochrane review.

AUTHORS' CONCLUSIONS

There are currently no RCTs that assess the efficacy and side effects of clozapine in people with intellectual disabilities and psychoses. Given the use of clozapine in this vulnerable population, there is an urgent need for a RCT of clozapine in people with a dual diagnosis of intellectual disability and psychosis to fill the evidence gap.

Obesity and overweight in intellectual and non-intellectually disabled children

BACKGROUND

Few studies have compared overweight and obesity in intellectually disabled (ID) and non-intellectually disabled (N-ID) children. This research compared the prevalence of overweight and obesity between a sample of 218 ID and 229 N-ID school pupils in Northern Ireland (NI). Comparison of the physical activity and dietary behaviour of the two groups of school pupils were also undertaken.

METHODS

Each pupil completed (assisted if required) a food intake and physical activity questionnaire. Following this body mass index (BMI) and waist circumference were measured and recorded.

RESULTS

Significantly more ID pupils (72, 33%) were overweight/obese compared with 55 (24%) of the N-ID pupils in accordance with their BMI. ID pupils also had significantly higher waist circumferences. Over a quarter of foods consumed by the pupils were fatty and sugary foods and close to 30% of these foods were eaten by the ID children. Pupils spent most of their time engaging in low levels of activity such as reading, watching TV, on games consoles and listening to music. Pupils with an ID spent fewer hours on moderate and high levels of activities compared with those children with N-ID.

CONCLUSIONS

Results of this study found higher levels of overweight and obesity in this sample than in international published research. Additionally significantly higher numbers of ID pupils were overweight and obese indicating the need for future research and public health to focus on this issue.

Pica in persons with developmental disabilities: approaches to treatment

Pica is a very serious problem in which an individual ingests substances without nutrition value, such as paper and paint. As this behavior is often life-threatening resulting in surgery, pica has received attention from researchers for several decades. During that time, a number of interventions have been devised, such as behavioral methods (e.g., aversive stimuli, overcorrection, time-out, reinforcement) and biological interventions (e.g., pharmacotherapy, nutritional supplements). This paper is a broad review of the research on treatment studies for this problem, with a focus on persons with autism and/or intellectual disability (ID), which constitutes almost all of the published treatment papers. In addition, strengths and weaknesses of different pica treatments are discussed. Upon review, applied behavior analysis (ABA) was found to have the most robust empirical support to treat this behavior. Most clinicians are drifting away from aversive techniques and relying on more positive procedures to guide their treatment plans. The implications of current status and future directions for research are also addressed.

Treatments for the challenging behaviours of adults with intellectual disabilities

OBJECTIVE

To provide an overview and critical assessment of common problems and best evidence practice in treatments for the challenging behaviours (CBs) of adults with intellectual disabilities (IDs).

METHOD

Commonly observed problems that present obstacles to successful treatment plans are discussed, followed by an analysis of available research on the efficacy of behavioural and pharmacological therapies.

RESULTS

Behavioural and pharmacological interventions are most commonly used when addressing CBs in people with IDs. However, within each of these techniques, there are methods that have support in the literature for efficacy and those that do not. As clinicians, it is important to follow research so that we are engaging in best practices when developing treatment plans for CBs.

CONCLUSIONS

One of the most consuming issues for psychiatrists and other mental health professionals who work with people who evince developmental disabilities, such as IDs, are CBs. These problems are very dangerous and are a major impediment to independent, less restrictive living. However, there is a major gap between what researchers show is effective and much of what occurs in real-world settings.

The Questions About Behavioral Function (QABF): current status as a method of functional assessment

Functional assessment has now entered the mainstream for evaluation and to aid in the treatment of challenging behaviors, while experimental functional analysis was at the forefront of this movement, this particular methodology has proven to be impractical, and thus has limited utility in real world settings. As a result of these factors standardized test have become a popular alternative for making a functional assessment. The most extensively studied of these scales to date is the Questions About Behavioral Function (QABF). This paper reviews the available research on this scale, its current status, and future directions.

The effects of gender and age on repetitive and/or restricted behaviors and interests in adults with autism spectrum disorders and intellectual disability

Frequency of repetitive and/or restricted behaviors and interests (RRBIs) was assessed in 140 adults with autism spectrum disorders (ASDs) and severe or profound intellectual disability (ID). The associations of gender and age range were analyzed with RRBI frequency which was obtained using the Stereotypies subscale of the Diagnostic Assessment for the Severely Handicapped-II (DASH-II). A significant main effect of gender was found. Male participants had higher frequency of RRBIs than females regardless of age range. There was not a significant main effect of age range or a significant interaction between gender and age range. Results and implications are discussed.

Developmental milestones in toddlers with atypical development

The attainment of developmental milestones was examined and compared in 162 infants and toddlers with developmental disabilities, including Down Syndrome (n = 26), Cerebral Palsy (n = 19), Global Developmental Delay (n = 22), Premature birth (n = 66), and Seizure Disorder (n = 29). Toddlers in the Seizures Disorder group began crawling at a significantly younger age than toddlers in the Down Syndrome and Cerebral Palsy groups. Additionally, toddlers in the Seizure Disorder group began walking at a younger age than children in the Down Syndrome, Cerebral Palsy, and Global Developmental Delay groups, while toddlers in the Prematurity group began walking at a younger age than children in the Down Syndrome group. No between group differences were found with respect to age at which first words were spoken. Results and their implications are discussed.

The relationship among side effects associated with anti-epileptic medications in those with intellectual disability

Seizures are fairly common in those with intellectual disabilities. In order to treat these seizures, antiepileptic drugs (AEDs) are often used and in many cases are effective. However, these medications often create a variety of associated side effects. In order to monitor these side effects, measures such as the SEIZES-B have been used. While many side effects have been found to occur with the use of AEDs, research has not explored if certain side effects are more likely to co-occur. For the current study, 281 people with intellectual disability were administered the SEIZES-B to monitor side effects associated with AEDs. Correlations between side effect subscales were then computed. Several subscales were found to be significantly correlated: hepatic disturbance with dermatological changes and cognitive disturbance; respiratory disturbance with dermatological changes, sedation, and electrolyte disturbance; and cognitive disturbance with sedation and dermatological disturbance. Possible implications of these findings are discussed.