Learning disability and epilepsy. 1, towards common outcome measures

Vagal Nerve Stimulation in Epilepsy: Experiences of Participants with Cognitive Deficits

INTRODUCTION

The purpose of this study was to examine patients' experiences of vagal nerve stimulation (VNS) with a special interest in patients with cognitive deficit (CD).

MATERIALS AND METHODS

An open, retrospective study was conducted on 82 patients with pharmacoresistant epilepsy, who were treated with VNS for at least 10 months. Based on the inability to live independently, they were divided into two groups: patients with cognitive deficit (CD group) and patients without cognitive deficit (non-CD group). A specially designed questionnaire was used for semi-structured interviews about patients' experiences of VNS treatment.

RESULTS

Approximately one-third described a continuous reduction of seizure frequency of 50% or more and were regarded as responders. Fewer subjects in the CD group were responders than in the non-CD group. Approximately one-third of all subjects had no positive effect of VNS treatment. More CD patients described additional improvements and the most common were milder seizures and improved alertness. The most commonly reported adverse effect was hoarseness.

DISCUSSION

VNS treatment in patients without CD had better effect on seizure frequency reduction than in patients with CD, but many patients with CD reported other benefits from the treatment.

CONCLUSION

Non-CD patients had higher seizure frequency reduction than CD patients during VNS treatment, but many CD patients described other benefits.

Lacosamide in patients with intellectual disability and refractory epilepsy

The objective of this study was to evaluate the tolerability and efficacy of lacosamide (LCM) in residential patients at our epilepsy centre. We assessed retrospectively 80 patients (mean age 36.2 years, range 18-63 years; 29 female) with intellectual disability (ID) and drug-resistant epilepsy using an industry-independent, non-interventional study design based on standardised seizure records. Evaluation, including calculation of retention rate, was carried out for the intervals 3-6, 9-12 and 21-24 months after LCM initiation. The Clinical Global Impression scale (CGI) was used to allow assessment of qualitative changes in seizure severity and clinical status. CGI improved for 61% of the patients. The responder rate was 48%; ten patients (13%) became seizure free. The response was not related to the degree of ID. The retention rates after 12 and 24 months were 71% and 65%, and were significantly lower in patients taking other sodium-channel blockers (SCBs; 76% vs. 55%). The occurrence of adverse events (AEs) was related to the administration of concomitant SCBs (48% with SCBs vs. 26% without). Sedation (15%), ataxia (13%), vertigo (11%), and nausea (9%) were the commonest AEs. While 60% of our patients had concomitant psychiatric diagnosis, we found no relevant effect of this on challenging behaviour. Adjunctive LCM may provide an antiepileptic treatment option for patients with ID with or without additional psychiatric diagnosis. The occurrence of AEs and the LCM retention rate were affected by concomitant SCB use but not by psychiatric comorbidity.

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".

Pharmacological interventions for epilepsy in people with intellectual disabilities

BACKGROUND

The prevalence of epilepsy among people with intellectual disabilities is much higher than in the general population. Seizures in this population are often complex and refractory to treatment and antiepileptic medication may have a profound effect upon behaviour (Kerr 1997).This is an updated version of a Cochrane Review first published in Issue 3, 2007.

OBJECTIVES

To assess the data available from randomised controlled trials (RCTs) of the efficacy of antiepileptic drug (AED) interventions in people with epilepsy and intellectual disabilities.

SEARCH METHODS

For the latest update of this review, we searched the Cochrane Epilepsy Group Specialised Register (2 September 2014), the Cochrane Central Register of Controlled Trials (CENTRAL) via the Cochrane Register of Studies Online (CRSO) (2 September 2014), MEDLINE (Ovid, 1946 to 3 September 2014) and PsycINFO (EBSCOhost, 1887 to 3 September 2014).

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials (RCTs) of pharmacological interventions for people with epilepsy and a learning disability.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. We contacted study authors for additional information. We assessed epilepsy/seizure, behavioural and cognitive outcomes, as well as quality of life and adverse effects.

MAIN RESULTS

We included 14 RCTs (1116 participants) in the present review. Data were heterogenous and a descriptive analysis is presented. In the majority of cases where antiepileptic drugs (AEDs) were trialled in this population, we found moderate reductions in seizure frequency in that there was a significantly higher rate of responders (reduction of 50% or more) in the treatment group compared with the placebo group, with some studies reporting a higher incidence of seizure freedom in the treatment group. In general, AEDs that are proven to be effective in the general epilepsy population are also effective for refractory epilepsy in people with intellectual disability. It is not possible to comment on the relative efficacy of medications, making clinical decisions difficult.In trial settings patients continued on treatment in the majority of cases. Placebo groups often experienced fewer adverse events. Where adverse events were experienced they appeared similar to those in the general population. The methods by which adverse events were recorded and reported appeared to be inconsistent, resulting in very large variation between studies. This is problematic as clinically relevant interpretation of these findings is limited.The quality of evidence provided in the present review is low to moderate. Additionally the majority of studies lacked or used non-reliable measures of behavioural exacerbation. However, where measured, little obvious impact on behaviour was seen in terms of behaviour disorder.

AUTHORS' CONCLUSIONS

This review broadly supports the use of AEDs to reduce seizure frequency in people with refractory epilepsy and intellectual disability. The evidence suggests that adverse events are similar to those in the general population and that behavioural adverse events leading to discontinuation are rare; however, other adverse effects are under-researched.

A qualitative study of carers' and professionals' views on the management of people with intellectual disability and epilepsy: a neglected population

Little attention has been paid to the specific needs of people with intellectual disability and epilepsy despite evidence of increased prevalence of epilepsy, increased risk of complex epilepsy, and heightened use of health services among this group. In an attempt to address this gap, an online international survey was undertaken inviting health professionals and caregivers, both paid and family members, to share their views on the adequacy and quality of available treatment. This paper reports on the responses obtained from 113 individuals from the UK and Ireland. Findings revealed that professionals and carers differ in their expectations of treatment and with regard to maximizing communication during consultations. In addition, findings suggested that the potential of consultations to provide information for carers, as well as to allay concerns, may not be realized. Rescue medications were viewed favorably; however, respondents expressed less satisfaction with routine medications. These findings may reflect a failure by professionals to appropriately transfer knowledge of these treatments.

Consensus guidelines into the management of epilepsy in adults with an intellectual disability

BACKGROUND

Epilepsy has a pervasive impact on the lives of people with intellectual disability and their carers. The delivery of high-quality care is impacted on by the complexity and diversity of epilepsy in this population. This article presents the results of a consensus clinical guideline process.

RESULTS

A Delphi process identified a list of priority areas for the development of evidence-based guidelines. All guidelines were graded and consensus on scoring was achieved across the guideline group.

CONCLUSION

There is a dearth of high-quality evidence from well-constructed studies on which to base guidance. However, the development of internationally derived consensus guidelines may further support the management of epilepsy in adults with an intellectual disability.

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.

Prevalence, patterns, service needs, and assessment of neuropsychiatric disorders among people with epilepsy in residential care: validation of the Neuropsychiatric Inventory as a caregiver-rated measure of neuropsychiatric functioning in epilepsy

We assessed 228 people with epilepsy (PWE) in the residential care setting using the Neuropsychiatric Inventory (NPI) and Brief Psychiatric Rating Scale (BPRS) as caregiver- and observer-rated instruments. There was a significant burden of psychopathology, about half of all subjects surveyed scoring positive on either or both instruments. Psychopathology as measured by the NPI and BPRS was significantly greater in cognitively impaired subjects than in those with intact cognitive function. The NPI was found to be a valid caregiver-rated measure of psychopathology in PWE, with a principal components analysis yielding a reliable and interpretable four-factor solution, psychosis, interictal dysphoric disorder, depression, and anxiety being identified. Mental health service needs were found to be considerable in this population, with a significant hidden burden of psychiatric comorbidity. As this population has ongoing service needs through the life span, further research is necessary.

The Evaluation of Behavioral Disturbances in Epilepsy

The evaluation of behavioral disturbances in epilepsy is an area fraught with complexity. On the one hand, there are no instruments that have been developed specifically for the assessment of behavioral disturbances in epilepsy. On the other hand, the phenomenology and pathophysiology of behavioral disturbances in epilepsy are unique and defy conventional descriptions in the psychiatric literature. The vast majority of studies have used instruments that have not been validated for this purpose. Studies with a psychiatric orientation generally tend to employ unvalidated semistructured or structured tools except for the Structured Clinical Interview for DSM, which has been validated for epilepsy. Studies with a neurological orientation generally use screening questionnaires and interpret the results of these as diagnostic. Neither approach is valid and both generally fail to measure potential confounders, such as seizure frequency, seizure severity, temporality of seizure occurrence in relation to time of assessment, life events, disablement, quality of life, and other socioeconomic indicators. Furthermore, instruments are generally employed using cutoff scores that may not be valid for epilepsy populations; the emphasis is often on symptom severity rather than symptom multiplicity (or load), which may also have an impact on the patient's outcome. In addition, instruments that have a basis in psychiatric criteria as opposed to symptomatology have inherent pitfalls at the interface between epilepsy and behavior. These and other issues in evaluating behavioral disturbances in people with epilepsy are reviewed and some solutions for the future are proposed.

Epilepsy, intellectual disability, and living environment: a critical review

Epilepsy occurs at a higher incidence and is more prevalent in people with an intellectual disability than in the general population. Nonetheless, we have insufficient knowledge of the extra needs of people with epilepsy and intellectual disability, of their families, and of the living environment. The lack of information about specific needs of the living environment may, in particular, be important. A Medline search revealed that scant attention has been paid to the specific needs for patients with epilepsy and intellectual disability, and only a few studies have focused specifically on this topic. The majority of studies have been focused on medical treatment issues and the organization and availability of health and social services. There is an indication that people with epilepsy and intellectual disability lack skills training appropriate to their intellectual potential. And although several reviews have emphasized the need for information on living environment and quality of life, we did not find such studies in our search.

A randomized, double-blind, placebo-controlled trial of topiramate in adults with epilepsy and intellectual disability: impact on seizures, severity, and quality of life

This randomized, double-blind, placebo-controlled UK trial evaluated the effect of topiramate as add-on therapy on seizure frequency, seizure severity, and quality of life in patients with epilepsy and intellectual disability. There were three phases: 4 weeks baseline, 18 weeks titration to 200-400 mg topiramate/day (adults) or 5-9 mg/kg/day (children), 12 weeks maintenance. Recruitment was low (88/120); analyses were underpowered. Seizure frequency varied enormously (median 17.7, maximum 1706.2). There was no significant difference in reduction in mean total seizure frequency or number of responders between the groups. Topiramate reduced seizure frequency by >30% from baseline (placebo 1%); post hoc analyses showed a trend toward significance (R ratio, P=0.052). There were no significant differences between the groups with respect to mean seizure severity or other outcome measures. Topiramate was generally well tolerated; body weight (P=0.015) and systolic blood pressure (P=0.043) were reduced. The study suggests that topiramate reduces seizure frequency in patients with epilepsy and intellectual disability without the added burden of behavior effects, and was potentially advantageous to physical well-being.

Exploring the evaluation of antiepileptic drug change in people with intellectual disabilities and high-frequency epileptic seizures: seizure control and sustained responsiveness to the environment

PURPOSE

Optimum antiepilepsy medication should be successful in reducing seizures with minimal adverse effects on the patient's ability to concentrate or general level of awareness. The purpose was to investigate the potential of a method of measuring responsiveness to environmental events as a means of reflecting awareness levels among people with intellectual disabilities undergoing review of medication for high-frequency epileptic seizures.

METHODS

Observations of 22 participants referred to a specialist clinic were conducted three times a month over a 5-month period following the initial baseline measures and clinical intervention. Behavioral responsiveness was measured by calculating the likelihood of appropriate activity occurring given the occurrence of staff interaction. This likelihood was represented by the statistic Yule's Q. Seizure frequency was also evaluated.

RESULTS

Participant responsiveness after drug review was similar to baseline indicating an absence of long-term adverse effects. Participants experienced a significant decrease in seizure frequency.

CONCLUSION

It was concluded that drug review led to seizure reduction while behavioral measurement confirmed no loss of responsiveness.

Pharmacological outcomes in people with mental retardation and epilepsy

The aim of this study was to examine prospective outcomes in mentally retarded people with epilepsy seen for the first time during 1998 until the end of 2001. Two hundred and fourteen patients (120 men, 94 women, aged 11-70 years [median 34 years]) were referred over this 4-year period. Median duration of follow-up was 18 months (range, 13-36 months). Seventeen (8%) had nonepileptic attacks only, 10 of whom were being treated with antiepileptic drugs (AEDs). The remaining 197 (92%) patients had epilepsy, the majority (n=151, 77%) presenting with focal seizures. A total of 22 patients were started on AED treatment, with seizure freedom for at least a year being achieved in 10 (45%). AED manipulation was undertaken in a further 136 patients, resulting in 59 (43%) becoming seizure-free. No relationship was found between extent of mental retardation and seizure control. There was no deterioration in mean caregiver scores rating sleep, appetite, alertness, and behavior. These findings suggest that AED therapy can result in seizure freedom in more than 40% of mentally retarded people with epilepsy without producing unacceptable toxicity.

Topiramate in patients with learning disability and refractory epilepsy

PURPOSE

Management of seizures in learning disabled people is challenging. This prospective study explored the efficacy and tolerability of adjunctive topiramate (TPM) in patients with learning disability and refractory epilepsy attending a single centre.

METHODS

Sixty-four patients (36 men, 28 women, aged 16-65 years) were begun on adjunctive TPM after a 3-month prospective baseline on unchanged medication. Efficacy end points were reached when a consistent response was achieved over a 6-month period at optimal TPM dosing. These were seizure freedom or > or =50% seizure reduction (responder). Appetite, behaviour, alertness, and sleep were assessed by caregivers throughout the study.

RESULTS

Sixteen (25%) patients became seizure free with adjunctive TPM. There were 29 (45%) responders. A further 10 (16%) patients experiencing a more modest improvement in seizure control continued on treatment at the behest of their family and/or caregivers. TPM was discontinued in the remaining nine (14%) patients, mainly because of side effects. Final TPM doses and plasma concentrations varied widely among the efficacy outcome groups. Many patients responding well to adjunctive TPM did so on < or =200 mg daily. Mean carer scores did not worsen with TPM therapy.

CONCLUSIONS

TPM was effective as add-on therapy in learning-disabled people with difficult-to-control epilepsy. Seizure freedom is a realistic goal in this population.

Development and validation of the Glasgow Epilepsy Outcome Scale (GEOS): a new instrument for measuring concerns about epilepsy in people with mental retardation

PURPOSE

To develop a measure for use with adults with epilepsy and mental retardation, capable of assessing both clinical and care concerns and of quantifying treatment outcomes.

METHODS

Extensive validational and other psychometric evaluation was undertaken, comprising initial scale development work with 48 carers and 46 health practitioners, followed by formal field testing on a sample of 186 patients, using 384 respondents (160 clinicians, 141 staff, 83 family). Recognised qualitative methods were applied to identify central themes, and psychometric procedures generated data on validity, reliability, and component structure.

RESULTS

A total of 1,007 items of concern was generated, which was reduced systematically to a representative set of 90 items. The GEOS-90 comprises four subscales: concerns about "seizures," "treatment," "caring," and "social impact," each explaining approximately 70% of variance. Subscales and factor scales had strong internal consistency (alpha > or = 0.82). Stepwise linear regression was applied to derive a short-form version with similar structure. Thirty-five items were retained (GEOS-35; alpha > or = 0.89). Both scales discriminated moderately on clinical variables (number of seizure types, mono- vs. polytherapy, seizure frequency; all values of p < 0.05) and demonstrated concurrent validity with interview ratings from the ELDQOL (p < 0.05).

CONCLUSIONS

The GEOS scales appear valid and reliable for use with clinical populations of people with mental retardation.

A randomized open-label study of gabapentin and lamotrigine in adults with learning disability and resistant epilepsy

The aim of this study was to evaluate the efficacy and safety of gabapentin in patients with learning disabilities and resistant epilepsy, comparing the effects of gabapentin with lamotrigine on efficacy, behaviour and mood. An open-label, randomized, parallel group, multicentre add-on study comparing gabapentin with lamotrigine in 109 patients with drug-resistant localization-related epilepsy and learning disabilities was conducted: 39 patients were randomized to gabapentin and 44 to lamotrigine. The study population had a range of learning disabilities and severe partial epilepsy. The percentage of patients achieving a greater than or equal to 50% reduction in seizure frequency on gabapentin was 50%, (mean reduction in seizures was 51%). Compared to 48.6% of lamotrigine patients, no statistically significant treatment differences could be identified. The safety profile of both drugs was consistent with that seen in previous clinical trials. Carer-rated visual analogue scales detected significant improvements (P< 0.05) for the gabapentin-treated patients in seizure severity, attention, general health and sleeping pattern, while for lamotrigine seizure severity improved significantly. For learning disabled patients with resistant epilepsy, gabapentin and lamotrigine provide safe and effective treatment, with positive benefits on behaviour.

Epilepsy and intellectual disability

A Medline and Psychline literature review of epilepsy in people with intellectual disability was performed. The review has highlighted the importance of the impact of epilepsy on the lives of individuals and their families, affecting physical morbidity, leading to an increased mortality and increasing the care-giving burden. Interventions with a strong evidence base are mainly pharmacological with an increasing body of work on the novel antiepileptic drugs. Surprisingly little research exists into the quality of service provision for this population. The authors suggest three areas for future work: (1) an increasing application of research methodologies such as direct observation and qualitative studies into this field; (2) an exploration of the broad impact of treatment and (3) the possibility that epilepsy is a barrier to care provision.

Learning disability and epilepsy. 2, a review of available outcome measures and position statement on development priorities

People with epilepsy plus learning disabilities pose a challenge in terms of clinical management and research investigation, and, to date, the measurement of outcomes in this population has been limited. There have been uncertainties concerning both the 'what' and the 'how' of assessment. This paper presents a comprehensive review of available outcome measures across nine domains, i.e. relating to seizures, drugs, cognitive function, behaviour, social functioning, carer functioning, attitudes, motivation and 'quality of life'. This last domain reflects more global measures designed to encompass several assessment strands. The uses and limitations of each scale is discussed and, where data are available, psychometric properties are also presented. The paper concludes with suggestions for the further development of outcome measures in this population.