Psychopathology in people with epilepsy and intellectual disability; an investigation of potential explanatory variables

Forensic neuropsychiatric aspects of epilepsy

Epilepsy may be associated with automatisms that are classed as 'insane 'as they are deemed to have originated within the mind. 'Sane automatism' is said to occur from external factors, such as physical trauma, while 'insane automatism' is said to be innate to the individual experiencing them. To claim automatism within the context of a criminal matter requires a detailed evaluation of the behavior demonstrated and a questioning of the volitional and purposeful nature of this behavior. It is insufficient to rely upon past behavior in association with these seizures to justify the defense of automatism within a specific event. Epilepsy is often considered to be associated with an increase in violence. Proper epidemiological research, both in long-term, large population control studies and hospital-based studies, has suggested that epilepsy, per se, is not associated with an increase in violence when compared to the population at large and controlled for other familial and environmental factors.

Self-injury as a predominant challenging behavior in epilepsy: A study in a residential facility for profoundly disabled patients

BACKGROUND

The association between challenging behavior (CB) and epilepsy in people with intellectual disability (ID) remains largely controversial.

AIM

To clarify the correlation between CB and epilepsy, we investigated the clinical characteristics of CB in both people with and without epilepsy among individuals with ID hospitalized in our residential facility.

METHODS AND PROCEDURES

A total of 63 individuals with CB was retrospectively investigated using the Behavior Problems Inventory, and the following items were collected from the medical records: sex, age, hospitalization period, etiology and risk factors, level of ID, type of CB, administration of psychotropic drugs, presence or absence of epilepsy and clinical features of epilepsy.

OUTCOMES AND RESULTS

Almost all individuals with CB showed profound ID. There was no significant difference in the rate of CB between people with and without epilepsy. A type analysis of CB revealed that self-injurious behavior was observed more frequently in epilepsy cases (66.7 %) than in cases without epilepsy (36.4 %) (p =  0.015), and self-injurious behavior was the predominant clinical form in people with epilepsy among the three subgroups of CB (self-injurious, aggressive and self-injurious and aggressive behavior).

CONCLUSIONS AND IMPLICATIONS

The high incidence of self-injurious behavior in epilepsy with profound disabilities may imply the presence of common pathological basis of self-injurious behavior and epilepsy.

Impact of intellectual and developmental disability on quality-of-life priorities in adults with epilepsy

OBJECTIVE

Adults living with intellectual and developmental disability (IDD) and epilepsy (IDD-E) face challenges in addition to those faced by the general population of adults with epilepsy, which may be associated with distinct priorities for improving health-related quality of life (HR-QOL). This study sought to (1) conduct a survey of HR-QOL priorities identified by adults with IDD-E and caregivers, and (2) perform an exploratory cross-sectional comparison to adults with epilepsy who do not have IDD.

METHODS

This cross-sectional study recruited 65 adults with IDD-E and 134 adults with epilepsy without IDD and caregivers. Using a three-step development process, 256 items from existing quality-of-life scales recommended by the American Academy of Neurology (AAN) were rated by patients/caregivers for their importance as HR-QOL priorities. HR-QOL items identified as critical to the majority of the sample of adults with IDD-E were reported. Health-related quality of life priorities were compared between adults with IDD-E and adults with epilepsy without IDD.

RESULTS

Health-related quality of life was significantly lower in adults with IDD-E. Health-related quality of life domains identified as critical priorities by adults with IDD-E included seizure burden, anti-seizure medication side effects, seizure unpredictability, and family impact. Priorities for improving HR-QOL differed between adults with and without IDD-E, with concerns about family impact, difficulty finding appropriate living conditions, inadequate assistance, and difficulty transitioning from pediatric-to-adult care valued significantly more among those with IDD-E.

SIGNIFICANCE

Intellectual and developmental disability is an important determinant of HR-QOL among adults with epilepsy. We report HR-QOL priorities identified by adults with IDD-E and their caregivers. These results may help epilepsy clinicians and researchers develop tailored strategies to address priorities of the patient with IDD-E/caregiver community.

The relationship between antiepileptic drug load and challenging behaviors in older adults with intellectual disability and epilepsy

Antiepileptic drugs (AEDs) may affect mood and behavior in people with epilepsy and intellectual disability. A high AED load, derived from AED polytherapy and/or high doses of AEDs, has been suggested to be a risk factor for behavioral side effects. Data were drawn from Wave 3 of the Intellectual Disability Supplement to the Irish Longitudinal Study on Ageing (IDS-TILDA). The Behavior Problems Inventory Short Form (BPI-S) was used to assess challenging behaviors. AED load was calculated and median AED loads obtained. Non-parametric tests and binary logistic regression were performed to determine the relationship between AED load and challenging behaviors. Of participants with a reported diagnosis of epilepsy who were taking a regular AED and had completed BPI-S (n = 142), 62.7% (n = 89) exhibited challenging behaviors. Challenging behavior was found to be more prevalent in those with more severe levels of intellectual disability (p < 0.001). Aggressive/destructive behavior and stereotyped behavior were significantly more likely in participants living in residential/campus settings. For participants with a severe/profound intellectual disability, a significantly higher median AED load was found for participants exhibiting aggressive/destructive behavior and self-injurious behavior (SIB) compared to participants not exhibiting these behaviors, indicating a high AED load may contribute to some behavioral problems in this population group. However, many factors can influence behavioral outcomes, creating difficulties in determining those that are associated and the nature of the association. Careful monitoring of AED load, together with increased vigilance for breakthrough behavioral issues is essential for dealing with these complex cases. Larger studies are needed to account for the potential confounding factors.

Association between epilepsy and psychiatric disorders in adults with intellectual disabilities: systematic review and meta-analysis

BACKGROUND

Psychiatric disorders, such as depression and anxiety, are commonly associated with epilepsy in the general population, but the relationship between psychiatric disorders and epilepsy among adults with intellectual disabilities is unclear.

AIMS

To conduct a systematic review and meta-analysis to assess whether epilepsy is associated with an increased rate of psychiatric disorders in adults with intellectual disabilities.

METHOD

We included literature published between 1985 and 2020 from four databases, and hand-searched six relevant journals. We assessed risk of bias by using SIGN 50 and the Cochrane risk of bias tool. Several meta-analyses were carried out.

RESULTS

We included 29 papers involving data on 9594 adults with intellectual disabilities, 3180 of whom had epilepsy and 6414 did not. Of the 11 controlled studies that compared the overall rate of psychiatric disorders between the epilepsy and non-epilepsy groups, seven did not show any significant inter-group difference. Meta-analysis was possible on pooled data from seven controlled studies, which did not show any significant inter-group difference in the overall rate of psychiatric disorders. The rates of psychotic disorders, depressive disorders and anxiety disorders were significantly higher in the non-epilepsy control groups compared with the epilepsy group, with effect sizes of 0.29, 0.47 and 0.58, respectively. Epilepsy-related factors did not show any definite association with psychiatric disorders.

CONCLUSIONS

It is difficult to pool data from such heterogeneous studies and draw any definitive conclusion because most studies lacked an appropriately matched control group, which will be required for future studies.

Improving Transitional Services for Adolescents and Young Adults with Epilepsy and Intellectual Disability

The transition from pediatric to adult health care systems is challenging for many adolescents with epilepsy and their families, and those challenges are compounded for adolescents with comorbid intellectual disabilities and epilepsy (ID-E). Many traditional transition pathways to adult care are inadequate, as they fail to address important considerations unique to the ID-E population or are absent entirely. Poor organization of care during critical transition periods increases the risks of sudden unexpected death in epilepsy, suboptimal seizure control, inadequate management of comorbidities, and poor psychological and social outcomes. The literature lacks systematic studies on effective transition programs for this population. The present review provides an overview of the main themes important in care transitions for the ID-E population: (1) precise diagnosis and management of seizures; (2) mental health and medical comorbidities affecting care; (3) accessing behavioral, habilitative, legal, financial, and community resources; and (4) caretaker support. We propose a specific framework which includes targeted recommendations of minimum care standards for youth with ID-E transitioning to adult care.

Intellectual Disability in Morocco: A Pilot Study

Objective: Intellectual disability (ID) is a heterogeneous group of disorders characterized by a congenital limitation in intellectual functioning and adaptive behaviour. Our present work aimed to describe the demographic and clinical characteristics in a series of Moroccan individuals with ID living in Fez city and its regions. Design: It was a prospective and descriptive exploratory monocentric study carried out between October 2014 and July 2019. We selected 186 patients diagnosed with ID at three different centers in Fez city. The data were processed and analyzed using the IBM SPSS version 24. Results: Our data revealed a high frequency of male patients with ID (67.2% in male patients vs. 32.8% in female patients). The male-to-female ratio was 2.04. The mean age of our patients was 15.52 ±6.59 years (mean±SD), ranging between 2 and 36 years. The mean age of fathers and mothers at the birth of their child with ID was 36 and 28 years, respectively. Several abnormal behaviors were observed: 23.1 percent delayed language learning, 17.7 percent anxiety, 12.9 percent aggressiveness, 19.18 percent concentration problems, and 5.4 percent hyperactivity. Epileptic seizures were the most common mental health disorder (21.72%) observed in our patients. Approximately 25 percent of patients with epilepsy took antiepileptic and/or neuroleptics to prevent the occurrence of seizures. Conclusion: A significant correlation was observed between ID associated to genetic causes and the increase of consanguinity rate.

Association between epilepsy and challenging behaviour in adults with intellectual disabilities: systematic review and meta-analysis

BACKGROUND

Previous systematic reviews showed no significant association between epilepsy and challenging behaviours in adults with intellectual disabilities.

AIMS

To identify whether there is an association between epilepsy and challenging behaviour in adults with intellectual disabilities by carrying out a systematic review of published data. PROSPERO registration number: CRD42020178092.

METHOD

We searched five databases and hand-searched six journals. Two authors independently screened titles, abstracts and full articles using a standardised eligibility checklist. Several meta-analyses were carried out.

RESULTS

The narrative analysis of data from 34 included articles (14 168 adults with intellectual disabilities, 4781 of whom also had epilepsy) showed no significant association between epilepsy and challenging behaviour. Meta-analysis was possible on data from 16 controlled studies. This showed no significant intergroup difference but after sensitivity analysis meta-analysis of 10 studies showed a significantly higher rate of overall challenging behaviour in the epilepsy group (effect size: 0.16) compared with the non-epilepsy group. Aggression and self-injurious behaviour both showed a statistically significant higher rate in the epilepsy group, with very small effect sizes (0.16 and 0.28 respectively). No significant intergroup difference was observed in the rate of stereotypy.

CONCLUSIONS

The findings are contradictory and must be interpreted with caution because of the difficulty in pooling data from varied studies, which is likely to introduce confounding. Where significant differences were found, effect sizes are small and may not be clinically significant, and there are major methodological flaws in the included studies, which should be addressed in future large-scale properly controlled studies.

Lacosamide in the general population and in people with intellectual disability: Similar responses?

PURPOSE

Epilepsy prevalence is significantly higher in people with Intellectual Disability (ID) compared to people with epilepsy (PWE) from the general population. Increased psychological and behavioural problems, healthcare costs, morbidity, mortality and treatment resistance to antiepileptic drugs (AEDs) is associated with epilepsy in ID populations. Prescribing AEDs for PWE and ID is challenging and influenced heavily by studies conducted with the general population. Our study compares Lacosamide (LCM) response for the ID population to those from the general population; using data from an UK based epilepsy database register (EP ID/PDD AED Register).

METHODS

Pooled retrospective case notes data for PWE prescribed LCM at 11 UK NHS Trusts were analysed. Participants were classified as per WHO guidance into groups of moderate-profound ID, mild ID and General population. Demographics, concomitant AEDs, starting and maximum dosage, exposure length, adverse effects, dropout rates, seizure frequency were collected. Group differences were reported as odds ratios estimated from univariable logistic regression models.

RESULTS

Of 232 consented participants, 156 were from the general population and 76 had ID (24 mild, 52 moderate-profound). Twelve month withdrawal rates and reasons, efficacy, side-effects, start and maximum doses were similar between the groups. Dose titration between baseline and three months was significantly slower in the ID group (p = 0.02).

CONCLUSION

There were no differences for LCM outcomes between general and ID groups. Slower LCM titration in ID populations in the first 3 months was associated with higher retention and lower behavioural side effects as compared to similar European studies.

Associated Risk Factors for Depression and Anxiety in Adults With Intellectual and Developmental Disabilities: Five-Year Follow Up

A better understanding of the factors associated with depression and anxiety in people with intellectual and developmental disabilities (IDD) is needed to provide guidelines for service providers, clinicians, and researchers as well as to improve the diagnostic process. The current study used a longitudinal dataset to explore demographic, health, and psychosocial risk factors of anxiety and depression in adults with IDD. Women were more likely to have depression while older adults, people with autism, and people with hearing impairments, were more likely to have anxiety. Chronic health conditions were associated with both anxiety and depression, while changes in stressful life events were associated with an increased risk of anxiety. Clinical and research contributions are discussed.

Treatment of psychiatric comorbidities in patients with epilepsy and intellectual disabilities: Is there a role for the neurologist?

This paper will explore the nature of psychiatric co-morbidities in people with an intellectual disability (ID) who have epilepsy. The complexity of clinical presentations and associated co-morbidities require thorough assessment utilising both neurological and psychiatric skills. The neurologist plays a central role in the management of epilepsy in people with ID and therefore requires basic competencies in the assessment of neuropsychiatric co-morbidities. This is key to liaison with other specialist services to ensure individuals receive holistic person-centred care. This article is part of the Special Issue "Obstacles of Treatment of Psychiatric Comorbidities in Epilepsy".

Experiences and support needs of informal caregivers of people with multimorbidity: a scoping literature review

Objective: Describe and synthesise existing published research on the experiences and support needs of informal caregivers of people with multimorbidity.Design: Scoping literature review. Primary database and secondary searches for qualitative and/or quantitative English-language research with an explicit focus on informal carers of people with multimorbidity (no date restrictions). Quality appraisal of included papers. Thematic analysis to identify key themes in the findings of included papers.Results: Thirty-four papers (reporting on 27 studies) were eligible for inclusion, the majority of which were rated good quality, and almost half of which were published from 2015 onwards. The review highlights common difficulties for informal carers of people with multiple chronic illnesses, including practical challenges related to managing multiple health care teams, appointments, medications and side effects, and psychosocial challenges including high levels of psychological symptomatology and reduced social connectedness. Current gaps in the literature include very few studies of interventions which may help support this caregiver group.Conclusion: Interest in this research area is burgeoning. Future work might fruitfully examine the potential benefits of audio-recorded health care consultations, and digitally delivered psychosocial interventions such as online peer support forums, for supporting and enhancing the caring activities and wellbeing of this caregiver group.

The occurrence of comorbidities with affective and anxiety disorders among older people with intellectual disability compared with the general population: a register study

BACKGROUND

Little is known regarding the burden of comorbidities among older people with intellectual disability (ID) who have affective and anxiety disorders. Therefore, we aimed to investigate the occurrence and risk of psychiatric and somatic comorbidities with affective and/or anxiety disorders in older people with ID compared to the general population.

METHODS

This population study was based on three Swedish national registers over 11 years (2002-2012). The ID group was identified in the LSS register, which comprises of data on measures in accordance with the Act Concerning Support and Service for Persons with Certain Functional Impairments (n = 7936), and a same-sized reference cohort from the Total Population Register was matched by sex and year of birth. The study groups consisted of those with affective (n = 918) and anxiety (n = 825) disorder diagnoses. The information about diagnoses were collected from the National Patient Register based on ICD-10 codes.

RESULTS

The rate of psychiatric comorbidities with affective and anxiety disorders was approximately 11 times higher for people with ID compared to the general reference group. The two most common psychiatric comorbidities occurred with affective and anxiety disorders were Unspecified non-organic psychosis and Other mental disorders due to brain damage and dysfunction and to physical disease (8% for each with affective disorders and 7 and 6% with anxiety disorders, respectively). In contrast, somatic comorbidity comparisons showed that the general reference group was 20% less likely than the ID cohort to have comorbid somatic diagnoses. The most commonly occurring somatic comorbidities were Injury, poisoning and certain other consequences of external causes (49 and 47% with affective and anxiety disorders, respectively) and Signs and symptoms and abnormal clinical and laboratory findings not elsewhere classified (44 and 50% with affective and anxiety disorders, respectively).

CONCLUSION

Older people with ID and with affective and anxiety diagnoses are more likely to be diagnosed with psychiatric comorbidities that are unspecified, which reflects the difficulty of diagnosis, and there is a need for further research to understand this vulnerable group. The low occurrence rate of somatic diagnoses may be a result of those conditions being overshadowed by the high degree of psychiatric comorbidities.

Mood, anxiety, and perceived quality of life in adults with epilepsy and intellectual disability

OBJECTIVE

Depression and anxiety symptoms are common among patients with epilepsy, but are relatively under-researched in patients with both epilepsy and intellectual disability (ID). The aim was to investigate whether epilepsy and ID characteristics are associated with mood, anxiety, and quality of life.

MATERIALS AND METHODS

Adult patients with epilepsy and ID who rely on tertiary epilepsy care were included (N = 189). Mood, anxiety, and quality of life were assessed by standardized questionnaires. Epilepsy and ID characteristics were retrieved from patient charts or determined by psychometric instruments.

RESULTS

Elevated levels of depressive and anxiety symptoms were present in 21.7% and 12.7%, respectively. Anxiety was significantly associated with a focal epilepsy type and ID domain discrepancy (substantial difference between two domains of adaptive behavior), but was negatively related to seizure frequency and drug load of mood-stabilizing antiepileptic drugs. Depressive symptoms were not significantly related to epilepsy characteristics, but a severe ID and ID domain discrepancy was associated with more depressive symptoms. Quality of life was significantly worse in those with multiple seizure types and ID domain discrepancy.

CONCLUSION

Whereas anxiety and quality of life are associated with individual epilepsy characteristics, this could not be confirmed for depressive symptoms in patients with epilepsy and ID, despite its high prevalence.

Medication use and potentially inappropriate prescribing in older adults with intellectual disabilities: a neglected area of research

It is known that for all adults, prevalence of potentially inappropriate prescribing (PIP) and polypharmacy increases with advancing age and morbidity. This has been associated with adverse drug reactions and poor outcomes. As a result, screening tools have been developed to identify PIP and to improve prescribing and health outcomes. A growing body of evidence supports the fact that there are even greater concerns among older adults with intellectual disability (ID) who are living longer than before but still have premature mortality and poorer health outcomes compared with the general population. They have different patterns of multimorbidity, with higher rates of epilepsy and mental health conditions. Polypharmacy is prevalent and some prescribing practices may be inappropriate. High exposure to anticholinergic and sedative medicines has additional adverse effects on quality of life. There may also be underutilization of clinically needed therapies. There has been substantial controversy internationally relating to extensive use of psychotropic medicines, particularly off-label use for challenging behaviours. Despite the mounting evidence and concerns about the impact of PIP on quality of life, health and safety for people with ID, appropriate methods to measure PIP are lacking, which represents an important gap in the research literature. Differences in morbidity and medicines use patterns in this population mean instruments used to identify inappropriate medicines in the older population are not suitable. In this perspective article we outline the specific health and medicinal needs for people with ID, the prevalence of polypharmacy and presentation of chronic health conditions in older adults with ID. We provide an overview of the psychotropic medicine classes most frequently used in people with ID which carry substantial risk. We highlight studies to date that have attempted to assess PIP and present research priorities to improve prescribing, health outcomes and quality of life for people with ID.

Challenging behavior in adults with epilepsy and intellectual disability: An analysis of epilepsy characteristics

PURPOSE

The study aimed to describe the frequency and severity of self-injurious, stereotyped, and aggressive/destructive behavior in adults with both epilepsy and intellectual disability (ID) who reside at a tertiary epilepsy center and to investigate the associations between challenging behavior and epilepsy and ID characteristics.

METHOD

The frequency and severity of self-injurious, (motoric) stereotyped, and aggressive/destructive behavior among 189 patients was assessed using the Behavior Problem Inventory. Comparisons were made with an adult reference population with ID, based on gender, to determine whether the behavior was clinically deviant. Epilepsy characteristics, including age at onset, epilepsy type, seizure types, seizure frequency, and use of antiepileptic drugs (AEDs), were retrieved from patient files. The level of ID was classified using the Diagnostic and Statistical Manual of Mental Disorders - Fifth Edition (DSM-5) and an ID domain discrepancy was allocated if there was a substantial difference between two domains of adaptive behavior within a subject.

RESULTS

Self-injurious behavior was present in 35% of subjects, stereotyped behavior in 60%, and aggressive/destructive behavior in 63%. The behavior exceeded clinical norms in 7%, 18%, and 12%, respectively. Aggression was the behavior evaluated most often as being problematic, despite its reported frequency being the lowest. When adjusting for level of ID and use of psychotropic medication, logistic regression analyses showed that self-injurious behavior was significantly associated with a lower number of AEDs (odds ratio (OR) = 0.4); that stereotyped behavior was significantly associated with a higher number of seizure types (OR = 1.4) and a lower number of AEDs (OR = 0.4); and that aggression was significantly associated with the presence of an ID domain discrepancy (OR = 3.1).

CONCLUSION

Challenging behavior is a serious issue among adults with epilepsy and ID. Although some of the epilepsy and ID characteristics seemed to contribute independently to these types of challenging behavior, the effects of epilepsy-related characteristics are modest when compared with ID.

Adjunctive lacosamide treatment for adult focal-onset epilepsy: focus on comorbid intellectual/developmental disorders and differing responses

Background

Data regarding lacosamide treatment as an adjunctive therapy in patients representative of a focal-onset epilepsy population including those with and without intellectual/developmental disorders (IDDs) are limited.

Purpose

To evaluate the retention rates of lacosamide in focal-onset epilepsy patients with and without IDD.

Patients and methods

We retrospectively reviewed all consecutive electronic and paper medical records of patients diagnosed with focal-onset epilepsy who were treated with lacosamide in two tertiary epilepsy centers.

Results

One hundred and thirty-six patients who met the inclusion criteria were studied. Number of patients with IDD was 46 (33.8%). Median lacosamide dose was 300 mg/day. A total of 39 patients (28.7%) experienced side effects, and 22 of them (16.2%) discontinued lacosamide. The 1-, 2-, and 3-year retention rates of lacosamide in patients with IDD were 68%, 62%, and 53%, respectively. Kaplan–Meier survival analysis showed that the retention rates were significantly lower in patients with IDD when compared to patients without IDD (P=0.04). Cox regression analysis showed that concomitant use of sodium channel blocker antiepileptic drugs (AEDs) was the only independent predictor of retention rate of lacosamide treatment (P=0.03). In the subgroup of patients with IDD, the analysis was performed again and the number of background AEDs was the only predictor for the retention rate of lacosamide (P=0.04).

Conclusion

When compared to patients without IDD, retention rates of lacosamide adjunctive therapy were lower in patients with IDD. However, these rates were higher than the rates suggested with previously registered AEDs including lamotrigine, levetiracetam, and topiramate. Therefore, irrespective of having comorbid IDD, we might suggest that lacosamide is a well-retained drug with a high efficacy profile in patients with focal-onset epilepsy.

Comparative survey of comorbidities in people with learning disability with and without epilepsy

Aims and Method

To ascertain the prevalence of epilepsy and understand the differences in the comorbidities of non-epileptic and epileptic patients with learning disabilities. A simple comparative survey was undertaken between the two main groups of patients: non-epileptic and epileptic.

Results

The prevalence of epilepsy in the study group was 30%. A total of 70% of patients with any type of challenging behaviour were in the non-epileptic group compared with 59% in the epileptic group. Depression was the most common diagnosis in both groups, being slightly more in the non-epileptic group.

Clinical Implications

Our study suggests that there is no association between epilepsy and the prevalence of challenging behaviour of psychiatric conditions within the learning disabilities population.

Epidemiology of mental health problems in adults with learning disability: an update

Epidemiological studies measuring prevalence rates and factors associated with mental health problems in adults with learning disability have produced very different and sometimes contradictory results, mainly because of methodological problems. Consequently, much of the epidemiology of mental health problems in this population is still unknown, although improved methodology and additional information are emerging. This article describes the methodological difficulties of studies, the reported prevalence rates in the context of these difficulties and what is currently known about the factors associated with mental health problems in this population.

Clinical services for adults with an intellectual disability and epilepsy: A comparison of management alternatives

Background

Intellectual disability (ID) is relatively common in people with epilepsy, with prevalence estimated to be around 25%. Surprisingly, given this relatively high frequency, along with higher rates of refractory epilepsy than in those without ID, little is known about outcomes of different management approaches/clinical services treating epilepsy in adults with ID—we investigate this area.

Materials & methods

We undertook a naturalistic observational cohort study measuring outcomes in n = 91 adults with ID over a 7-month period (recruited within the period March 2008 to April 2010). Participants were receiving treatment for refractory epilepsy (primarily) in one of two clinical service settings: community ID teams (CIDTs) or hospital Neurology services.

Results

The pattern of comorbidities appeared important in predicting clinical service, with Neurologists managing the epilepsy of relatively more of those with neurological comorbidities whilst CIDTs managed the epilepsy of relatively more of those with psychiatric comorbidities. Epilepsy-related outcomes, as measured by the Glasgow Epilepsy Outcome Scale 35 (GEOS-35) and the Epilepsy and Learning Disabilities Quality of Life Scale (ELDQoL) did not differ significantly between Neurology services and CIDTs.

Discussion

In the context of this study, the absence of evidence for differences in epilepsy-related outcomes amongst adults with ID and refractory epilepsy between mainstream neurology and specialist ID clinical services is considered. Determining the selection of the service managing the epilepsy of adults with an ID on the basis of the skill sets also required to treat associated comorbidities may hence be a reasonable heuristic.

Psychiatric side effects and antiepileptic drugs: Observations from prospective audits

Psychiatric comorbidities are common in people with epilepsy. A retrospective study of characteristics associated with withdrawal due to psychiatric side effects was undertaken in patients with treated epilepsy participating in prospective audits with new antiepileptic drugs (AEDs). A total of 1058 treated patients with uncontrolled seizures (942 focal-onset seizures, 116 generalized genetic epilepsies [GGEs]) participated in eight prospective, observational audits from 1996 to 2014. These patients were prescribed adjunctive topiramate (n=170), levetiracetam (n=220), pregabalin (n=135), zonisamide (n=203), lacosamide (n=160), eslicarbazepine acetate (n=52), retigabine (n=64), or perampanel (n=54). Doses were titrated according to efficacy and tolerability to optimize zeizure outcomes and reduce side effects. Psychiatric comorbidities were recorded prior to and after the addition of each AED. At baseline, patients with focal-onset seizures (189 of 942; 20.1%) were statistically more likely to have psychiatric diagnoses compared to patients with GGEs (14 of 116, 12.1%; p=0.039). Following adjunctive AED treatment, neuropsychiatric adverse effects led to AED withdrawal in 1.9-16.7% of patients. Patients with a pre-treatment psychiatric history (22 of 209; 10.5%) were statistically more likely to discontinue their new AED due to psychiatric issues compared to patients with no previous psychiatric diagnosis (50 of 849; 5.9%; p=0.017). Patients receiving sodium channel blocking AEDs (4 of 212, 1.9%) were statistically less likely to develop intolerable psychiatric problems, compared to those on AEDs possessing other mechanisms of action (68 of 846, 8.0%; p=0.012). Depression was the commonest problem, leading to discontinuation of AEDs in 2.8% (n=30) patients. Aggression was statistically more common in men (11 of 527, 2.1%) compared to women (1 of 531, 0.2%; p=0.004). Patients with learning disability (12 of 122, 9.8%; p=0.0015) were statistically less likely to have psychiatric issues prior to adjunctive AED treatment compared to other patients (208 of 936, 22.2%), but there were no statistically significant differences once the new AEDs were added (8 of 122 patients with learning disability, 6.6%; 64 of 936 other patients, 6.8%). Awareness of these issues may assist clinicians in avoiding, identifying and treating psychiatric comorbidities in people with epilepsy.

Type and Intensity of Negative Life Events Are Associated With Depression in Adults With Intellectual Disabilities

This study investigated the associations between types and intensity of life events and symptoms of depression among adults with intellectual disabilities. A community sample (N = 593) was screened for current depression and exposure to life events (i.e., loss, illness, change, and bullying) during the previous 12 months. Symptoms of depression were measured using the Psychopathology Checklists for Adults With Intellectual Disabilities. Exposure to three of the four types of life events studied (loss, illness, and bullying) and the intensity of the events were associated with depression, particularly in the cases of loss of relatives and bullying. Quality of care moderated the association between bullying and depression and may buffer the adverse consequences of bullying.

A systematic review of neuropsychiatric comorbidities in patients with both epilepsy and intellectual disability

Epilepsy is a neurological condition that is particularly common in people with intellectual disability (ID). The care for people with both epilepsy and ID is often complicated by the presence of neuropsychiatric disorders, defined as psychiatric symptoms, psychiatric disorders, and behavioral problems. The aim of this study was to investigate associations between epilepsy or epilepsy-related factors and neuropsychiatric comorbidities in patients with ID and between ID and neuropsychiatric comorbidities in patients with epilepsy. We performed a systematic review of the literature, published between January 1995 and January 2015 and retrieved from PubMed/Medline, PsycINFO, and ERIC and assessed the risk of bias using the SIGN-50 methodology. Forty-two studies were identified, fifteen of which were assessed as having a low or acceptable risk-of-bias evaluation. Neuropsychiatric comorbidities were examined in relation to epilepsy in nine studies; in relation to epilepsy-related factors, such as seizure activity, seizure type, and medication in four studies; and in relation to the presence and degree of ID in five studies. We conclude that the presence of epilepsy only was not a clear determinant of neuropsychiatric comorbidity in patients with ID, although a tendency towards negative mood symptoms was identified. Epilepsy-related factors indicating a more severe form of epilepsy were associated with neuropsychiatric comorbidity as was the presence of ID as compared to those without ID in patients with epilepsy, although this should be validated in future research. A large proportion of the studies in this area is associated with a substantial risk of bias. There is a need for high quality studies using standardized methods to enable clear conclusions to be drawn that might assist in improving the quality of care for this population.

Multidisciplinary assessment and treatment of self-injurious behavior in autism spectrum disorder and intellectual disability: integration of psychological and biological theory and approach

The objective of this review is to consider the psychological (largely behavioral) and biological [neurochemical, medical (including genetic), and pharmacological] theories and approaches that contribute to current thinking about the etiology and treatment of self-injurious behavior (SIB) in individuals with autism spectrum disorder and/or intellectual disability. Algorithms for the assessment and treatment of SIB in this context, respectively, from a multidisciplinary, integrative perspective are proposed and challenges and opportunities that exist in clinical and research settings are discussed.

Delivery of epilepsy care to adults with intellectual and developmental disabilities

Epilepsy is common in people with intellectual and developmental disabilities (IDD). In adulthood, patients with IDD and epilepsy (IDD-E) have neurologic, psychiatric, medical, and social challenges compounded by fragmented and limited care. With increasing neurologic disability, there is a higher frequency of epilepsy, especially symptomatic generalized and treatment-resistant epilepsies. The causes of IDD-E are increasingly recognized to be genetic based on chromosomal microarray analysis to identify copy number variants, gene panels (epilepsy, autism spectrum disorder, intellectual disability), and whole-exome sequencing. A specific genetic diagnosis may guide care by pointing to comorbid disorders and best therapy. Therapy to control seizures should be individualized, with drug selection based on seizure types, epilepsy syndrome, concomitant medications, and comorbid disorders. There are limited comparative antiepileptic drug data in the IDD-E population. Vagus nerve and responsive neural stimulation therapies and resective surgery should be considered. Among the many comorbid disorders that affect patients with IDD-E, psychiatric and sleep disorders are common but often unrecognized and typically not treated. Transition from holistic and coordinated pediatric to adult care is often a vulnerable period. Communication among adult health care providers is complex but essential to ensure best care when these patients are seen in outpatient, emergency room, and inpatient settings. We propose specific recommendations for minimum care standards for people with IDD-E.

Determinants of disease severity in adults with epilepsy: Results from the Neurological Diseases and Depression Study

BACKGROUND

Epilepsy severity has been recognized as a significant predictor of health-related quality of life in patients with epilepsy. However, clinical markers of epilepsy severity such as seizure frequency often fail to capture important aspects of the disease. This study investigates the factors associated with patient-reported severity of epilepsy, assessed by the Global Assessment of Severity of Epilepsy (GASE) scale in adults with epilepsy.

METHODS

Data from a cohort of 250 patients consecutively enrolled in the Neurological Diseases and Depression Study (NEEDS) were used to assess the determinants of epilepsy severity as measured by the GASE scale. Multiple linear regression analyses were used to examine the mediation effect of clinical and sociodemographic characteristics on patients' ratings on the GASE scale.

RESULTS

The mean age of the study participants was 39.8 (SD=14.9) years, of which 44.4% were male. About 66.8% of the participants reported "not at all severe" or "a little severe" epilepsy, while 0.4% reported "extremely severe" epilepsy. One-year seizure freedom, number of antiseizure medications, medication side effects, depression, anxiety, and seizure-related disability were identified as significant determinants of patients' ratings of epilepsy severity. Seizure-related disability mediated the effects of 1-year seizure freedom, number of antiseizure medications, and medication side effects on epilepsy severity.

CONCLUSION

Overall, patients with epilepsy who reported higher GASE scores were less likely to achieve 1-year seizure freedom and more likely to be on more antiseizure medications, experience more side effects from medication, endorse more depression and anxiety symptoms, and have increased self-reported seizure-related disability. The identified determinants of global, self-rated epilepsy severity can aid the design of appropriate interventions and support services for patients with severe epilepsy.

Epidemiology of epilepsy in older adults with an intellectual disability in Ireland: associations and service implications

There are limited studies on the prevalence of epilepsy and co-morbid conditions in older adults with an ID. To begin to address this prevalence of epilepsy was estimated for participants in the Intellectual Disability Supplement to the Irish Longitudinal Study on Ageing. Associations with demographic variables and co morbid health conditions were examined. It was found that prevalence was high (30.7%); but declined as people aged. Those with epilepsy were less likely to live with family, independently or in community settings, rates of refractory epilepsy were high and, despite medication over half of those with epilepsy still reported experiencing seizures. Given these findings, people with ID and their careers have considerable needs for information about epilepsy management, and for support from specialist ID and epilepsy services.

Enrichment and training improve cognition in rats with cortical malformations

Children with malformations of cortical development (MCD) frequently have associated cognitive impairments which reduce quality of life. We hypothesized that cognitive deficits associated with MCD can be improved with environmental manipulation or additional training. The E17 methylazoxymethanol acetate (MAM) exposure model bears many anatomical hallmarks seen in human MCDs as well as similar behavioral and cognitive deficits. We divided control and MAM exposed Sprague-Dawley rats into enriched and non-enriched groups and tested performance in the Morris water maze. Another group similarly divided underwent sociability testing and also underwent Magnetic Resonance Imaging (MRI) scans pre and post enrichment. A third group of control and MAM rats without enrichment were trained until they reached criterion on the place avoidance task. MAM rats had impaired performance on spatial tasks and enrichment improved performance of both control and MAM animals. Although MAM rats did not have a deficit in sociability they showed similar improvement with enrichment as controls. MRI revealed a whole brain volume decrease with MAM exposure, and an increase in both MAM and control enriched volumes in comparison to non-enriched animals. In the place avoidance task, MAM rats required approximately 3 times as long to reach criterion as control animals, but with additional training were able to reach control performance. Environmental manipulation and additional training can improve cognition in a rodent MCD model. We therefore suggest that patients with MCD may benefit from appropriate alterations in educational strategies, social interaction and environment. These factors should be considered in therapeutic strategies.

Behavioral pain indicators in people with intellectual disabilities: a systematic review

People with intellectual disabilities (IDs) have a higher risk of painful medical conditions. Partly because of the impaired ability to communicate about it, pain is often undertreated. To strengthen pain assessment in this population, we conducted a systematic review to identify behavioral pain indicators in people with IDs by using Embase, PubMed, PsycINFO, CINAHL, and Cochrane. Inclusion criteria were 1) scientific papers; 2) published in the last 20 years, that is, 1992 to 2012; 3) written in English, 4) using human subjects, 5) intellectual disabilities, 6) pain, 7) behavior, and 8) an association between observable behavior and pain experience. From 527 publications, 27 studies were included. Pain was acute in 14 studies, chronic in 2 studies, both acute and chronic in 2 studies, and unspecified in 9 studies. Methodological quality was assessed with the Mixed Methods Appraisal Tool. Of the 14 categories with behavioral pain indicators, motor activity, facial activity, social-emotional indicators, and nonverbal vocal expression were the most frequently reported. Most of the behavioral pain indicators are reported in more than 1 study and form a possible clinical relevant set of indicators for pain in people with IDs. Determination of a behavioral pattern specific for pain, however, remains a challenge for future research.

PERSPECTIVE

This review focuses on categories of behavior indicators related to pain in people with IDs. The quality of evidence is critically discussed per category. This set of indicators could potentially help clinicians to recognize pain in this population, especially when unique individual pain responses are also identified.

Factors associated with depression and anxiety in older adults with intellectual disabilities: results of the healthy ageing and intellectual disabilities study

OBJECTIVE

The objective of this article is to study which factors are associated with depression and anxiety in older adults with intellectual disabilities (ID).

METHODS

Depressive and anxiety symptoms were studied in 990 participants with borderline to profound ID, aged ≥ 50 years, using self-report and informant-report screening questionnaires. In 290 participants, major depression and anxiety disorders were assessed with a standardised psychiatric interview. Associations with personal, medical and psychosocial factors, which were collected through questionnaires and participants' medical and psychological records, were studied using multiple logistic regression analysis.

RESULTS

Increased depressive symptoms were positively associated with increased anxiety symptoms, number of life events during the past year and chronic diseases (heart failure, stroke, chronic obstructive pulmonary disease, coronary artery disease, diabetes mellitus and malignity in the previous 5 years) and negatively with instrumental activities of daily living (IADL) abilities. Major depression was positively associated with chronic diseases and negatively with IADL abilities. Increased anxiety symptoms were positively associated with borderline or mild ID and increased depressive symptoms and negatively associated with Down syndrome, epilepsy and social contacts. Anxiety disorders showed no significant associations.

CONCLUSIONS

To develop effective prevention and treatment policies, factors associated with depression and anxiety in older adults with ID should be further examined in longitudinal research.

Treatment of behavioral problems in intellectually disabled adult patients with epilepsy

Behavioral disorders are common in people with epilepsy and intellectual disability. Although in some genetic disorders behavioral problems are part of the established phenotype, they may also be a manifestation of underlying physical or mental illness, or may be unrecognized seizure activity. In light of this, assessment of behavioral disorders should take into account person factors such as the physical health and mental state of the person and environmental factors such as the quality of their interactions with carers and their living conditions. Video-electroencephalography ( EEG) is recommended where possible. We review potential pharmacologic and behavioral management strategies for behavioral disorders in people with intellectual disability.

Midwives' knowledge of, attitudes towards and experiences of caring for women with intellectual disability during pregnancy and childbirth: a cross-sectional study in Sweden

OBJECTIVE

to investigate midwives' knowledge of, attitudes towards and experiences of caring for women with intellectual disability (ID) during pregnancy and childbirth.

DESIGN/SETTING

a cross-sectional study among six hundred midwives working at antenatal care and labour wards in Sweden.

RESULTS

more than four out of five (81.5%) midwives had experience of caring for women with ID. Almost all midwives (97.1%) reported that caring for women with ID is different from caring for women without ID. Almost one-half (47.3%) had not received any education about pregnancy and delivery of women with ID, and a majority of the midwives (95.4%) requested evidence-based knowledge of women with ID in relation to childbirth. High proportion (69.7%) of the midwives were of the opinion that women with ID cannot satisfactorily manage the mother role, and more than one-third (35.7%) of the midwives considered that women with ID should not be pregnant and give birth at all. Most midwives partly/totally agreed that children of women with ID should grow up with their parents supported by the social authorities, but nearly one-fifth (19.1%) partly/totally agreed that the children should grow up in foster care.

CONCLUSIONS

even if the majority of midwives had experience of caring for women with ID, they were uncertain about how to adapt and give advice and they needed more knowledge about these women. Some midwives had negative attitudes towards childbearing among women with ID. Health Service providers should encourage midwives to update their knowledge and provide supportive supervision in midwifery care for women with ID.

Prevalence of depression and anxiety in older users of formal Dutch intellectual disability services

BACKGROUND

Little is known about the prevalence of depression and anxiety among older people with intellectual disabilities (ID). Therefore, the aim of this study was to study the prevalence of depression and anxiety in this population.

METHOD

This study is a cross-sectional epidemiologic multicentre study which was part of the "Healthy Ageing and Intellectual Disabilities" study. The study population consisted of 990 participants aged ≥50 years with borderline to profound ID which were screened with self-report and informant-report instruments; 290 of them were assessed with a standardized diagnostic interview.

RESULTS

Depressive symptoms were prevalent in 16.8% (95% CI: 14.4-19.1) and significantly associated with higher age. Anxiety symptoms were prevalent in 16.3% (95% CI: 14.0-18.6) and significantly associated with female gender and borderline to mild ID. Major depressive disorder was prevalent in 7.6% (95% CI: 5.2-11.0), anxiety disorders in 4.4% (95% CI: 2.6-7.0) and both in 0.7% (95% CI: 0.2-1.6). There was no relationship with gender, age or level of ID.

LIMITATIONS

For most participants, informant-report instruments have been used instead of self-report to overcome communication difficulties or inabilities. Also, a standardized psychiatric diagnostic interview has been used instead of psychiatric diagnoses made by an experienced psychiatrist.

CONCLUSION

Prevalence of major depressive disorder is higher and of anxiety disorders lower than in the Dutch general older community-dwelling population.

Epidemiologic and clinical characteristics of 458 Tunisian patients with intellectual deficiency and a reconsidered diagnostic strategy

Intellectual Deficiency (ID) is a common neuropsychiatric disorder whose etiopathogenesis still insufficiently understood. In the last decade, several surveys, assessing epidemiologic, clinical and etiologic parameters of ID, have been performed but none of them is realized in a Tunisian population. In this retrospective survey, we propose to study these parameters, in a Tunisian cohort of 458 patients with constitutional ID, and to assess our diagnostic strategy. Data analyses, by the SPSS program, reveal a male predominance, a high level of consanguinity, an advanced mean age of patients, a rare frequentation of specialized institutions by the severely affected patients, and a high frequency of familial forms with predominance of the recessive autosomal ones. The study of clinical parameters and investigations' results shows that 72.1% of our patients present a syndromic ID. For these patients, chromosomal anomalies are rarely described, EEG anomalies were usually non-specific in patients without clinical evidence of epilepsy, and brain anomalies are common in patients with severe ID, neurological symptoms or history of seizures. Aetiology is identified in 13.1% of them whereas it is still unknown in 100% of patients with non-specific ID. This study allows us to better characterize, epidemiologically and clinically, the first large Tunisian cohort of patients with ID and to assess our diagnostic strategy in order to propose a revised one that will improve the diagnostic lead, the care chain and the preventive resources of ID.

Pregnancy and birth outcomes of women with intellectual disability in Sweden: a national register study

OBJECTIVE

To investigate the antenatal health and demographic factors as well as pregnancy and delivery outcomes in women with intellectual disability (ID) in Sweden.

DESIGN

A population-based register study.

SETTING

The National Patient Register (NPR) linked to the Medical Birth Register (MBR).

SAMPLE

Women with ID classified as International Classification of Diseases (ICD) 8-10 who gave birth in 1999-2007 (n = 326), identified from the NPR linked to the MBR, were compared with all first-time, singleton mothers without ID or any other psychiatric diagnoses during this period in Sweden (n = 340 624).

METHODS

Population-based data were extracted from the NPR and the MBR.

MAIN OUTCOME MEASURES

Health and socio-demography at first antenatal visit, mode of delivery, pain relief during labor, preterm birth and discharge from hospital.

RESULTS

A higher proportion of women with ID were teenagers (18.4 vs. 3.3%), obese (20.1 vs. 8.6%) and single (36.6 vs. 6.2%) compared with women without ID, and women with ID smoked more often (27.9 vs. 7.9%). Women with ID had more often a preterm birth (12.2 vs. 6.1%), a cesarean section (CS) (24.5 vs. 17.7%) and used less nitrous oxide as pain relief during labor (59.5 vs. 75.8%). Women with ID had a higher risk for preterm birth [odds ratio (OR) 1.68], CS (OR1.55), non-use of nitrous oxide (OR 1.89) and discharge from hospital to a place other than home (OR 2.24).

CONCLUSION

Pregnant women with ID should be considered a risk group suggesting that better tailored pre- and intrapartum care and support are needed for these women.

Physical conditions and challenging behaviour in people with intellectual disability: a systematic review

BACKGROUND

Challenging behaviour is a major problem among people with intellectual disabilities. Physical factors may be an important cause. The aim of the present systematic review was to determine the physical conditions associated with challenging behaviour.

METHODS

A literature search was conducted in PubMed and the Cochrane systematic review database for empirical studies published between 1990 and 2008. The quality of all the studies that met the inclusion criteria was assessed using the SIGN-50 methodology checklists.

RESULTS

The search identified 45 studies, which looked at general medical conditions, motor impairment, epilepsy, sensory impairment, gastrointestinal disease, sleep disorders, dementia and others. There were four high-quality observational studies, seven well-conducted observational studies, 21 observational studies of low methodological quality and 13 non-analytical studies. There were significant and independent associations between challenging behaviours and urinary incontinence, pain related to cerebral palsy and chronic sleep problems, and between self-injurious behaviour and visual impairment. No association was found with hearing impairment, bowel incontinence, mobility impairment or epilepsy. Many other physical conditions were not addressed at all.

CONCLUSION

Medical conditions can play a role in challenging behaviour, and this should be evaluated in the clinical setting. So far, the level of evidence is generally low, and longitudinal studies are completely lacking. We recommend a systematic approach to research examining the role of physical conditions in challenging behaviour, the ultimate aim being to establish a basis for the development of clinical guidelines.

Epilepsy and intellectual disability: does epilepsy increase the likelihood of co-morbid psychopathology?

Although epilepsy is particularly common among people with intellectual disability (ID) it remains unclear whether it is associated with an increased likelihood of co-morbid psychopathology. We therefore investigated rates of mental health problems and other clinical characteristics in patients with ID and epilepsy (N = 156) as compared to patients with ID but no epilepsy (N = 596). All participants were consecutive referrals to specialist mental heath services. Specialist clinicians agreed on the mental health diagnoses by applying ICD-10 clinical criteria using information gained from interviews with key informants and the patients. Bivariate and multivariate analyses showed that patients with epilepsy were more likely to live in residential housing and have severe ID in line with previous evidence. However, the presence of epilepsy was not associated with an increased likelihood of co-morbid psychopathology. On the contrary, rates of mental health problems, including schizophrenia spectrum, personality and anxiety disorders, were significantly lower among patients with epilepsy. The results are discussed in the context of mood-stabilizing and other psychotropic effects of anti-epileptic drugs in adults with ID and epilepsy, as well as possible diagnostic overshadowing.

Mental health problems in adults with Williams syndrome

Although many researchers have investigated emotional and behavioral difficulties in individuals with Williams syndrome, few have used standardized diagnostic assessments. We examined mental health problems in 92 adults with Williams syndrome using the Psychiatric Assessment Schedule for Adults with Developmental Disabilities-PAS-ADD (Moss, Goldberg, et al., 1996). Factors potentially associated with mental health problems were also explored. The PAS-ADD identified mental health problems in 24% of the sample. The most common were anxiety (16.5%) and specific phobias (12%). Other diagnoses included depression, agoraphobia, and social phobia. No association was found between the presence of mental health problems and either individual (e.g., age, IQ, language level) or external (life events) variables.

The psychosocial impact of epilepsy in adults with an intellectual disability

Epilepsy has a pervasive impact on the quality of life, and thus the psychosocial well-being, of adults with an intellectual disability. Social and economical well-being appears to be affected by an increase in restrictions on activities and thus social contact. The population has very high rates of challenging behaviors and of mental illness. It is likely that these have a significant impact on epilepsy management. When populations with and without epilepsy are controlled for level of ability, no difference in prevalence of behavior or mental illness is seen between the populations. Current knowledge is limited on crucial issues such as the long-term effect of seizure disorder on mental health, quality of life, and cognition.

Best clinical and research practice in adults with an intellectual disability

Though the prevalence of epilepsies is substantially higher in people with intellectual disability (ID) compared with the general population, little is known of the psychosocial burden of epilepsy and adjustment and their respective determinants in this important population. In most modern societies, adult life with an ID is characterized by diminished self-determination, autonomous function, and life choices. These factors alone are known to be critically linked to the individual's overall quality of life. The task is to identify additional burdens attributable to coexisting epilepsy. This article addresses the significance, for people with ID who have epilepsy, of the many different factors, including seizure or epilepsy-related parameters, antiepileptic medication, coexisting motor and sensory impairments, and psychopathological and behavioral disorders, that can impact their quality of life. Discussion also covers the methodological difficulties in published studies, and, finally, proposals are outlined for future research in this field.

Physical mobility limitations in adults with intellectual disabilities: a systematic review

BACKGROUND

Mobility limitations increase with age in the general population. Despite a growing population of older adults with intellectual disabilities (ID), mobility is rarely studied in the ID literature. The specific aim of this study was to identify and summarise primary literature investigating mobility limitations in adults with ID.

METHODS

This study was a systematic review of the epidemiological literature (incidence and prevalence) of mobility limitations among adults with ID. Four electronic databases were searched from January 1980 to May 2007 for publications according to predefined inclusion/exclusion criteria. Additional sources were consulted. Two reviewers extracted data from each of the included articles.

RESULTS

Thirty-two publications representing 31 studies were ultimately included. In general, studies did not focus on mobility but were conducted for other purposes. All studies were conducted in industrialised countries. Only one study used a longitudinal design; the remainders were cross-sectional. Few investigators reported on the representativeness of the sample or the validity of the measurement tool. Study samples differed substantially and investigators used numerous definitions of mobility limiting comparability between studies.

CONCLUSIONS

There is a need for increased research on mobility limitations among adults with ID, particularly longitudinal research. Researchers investigating mobility limitations should use validated measurement tools and offer detailed descriptions of the study sample and how it compares with an identifiable population.