Safety and efficacy of anticonvulsants in elderly patients with psychiatric disorders: oxcarbazepine, topiramate and gabapentin

Gabapentin and pregabalin to treat aggressivity in dementia: a systematic review and illustrative case report

AIMS

The prevalence of dementia is rising as life expectancy increases globally. Behavioural and psychological symptoms of dementia (BPSD), including agitation and aggression, are common, presenting a challenge to clinicians and caregivers.

METHODS

Following PRISMA guidelines, we systematically reviewed evidence for gabapentin and pregabalin against BPSD symptoms of agitation or aggression in any dementia, using six databases (Pubmed, CINHL, PsychINFO, HealthStar, Embase, and Web of Science). Complementing this formal systematic review, an illustrative case of a patient with BPSD in mixed Alzheimer's/vascular dementia, who appeared to derive benefits in terms of symptom control and functioning from the introduction of gabapentin titrated up to 3600 mg day^-1 alongside other interventions, is presented.

RESULTS

Twenty-four relevant articles were identified in the systematic review. There were no randomized trials. Fifteen papers were original case series/case reports of patients treated with these compounds, encompassing 87 patients given gabapentin and six given pregabalin. In 12 of 15 papers, drug treatment was effective in the majority of cases. The remaining nine papers were solely reviews, of which two were described as systematic but predated PRISMA guidelines. Preliminary low-grade evidence based on case series and case reviews suggests possible benefit of gabapentin and pregabalin in patients with BPSD in Alzheimer's disease. These benefits cannot be confirmed until well-powered randomized controlled trials are undertaken. Evidence in frontotemporal dementia is lacking.

CONCLUSION

Gabapentin and pregabalin could be considered for BPSD when medications having stronger evidence bases (risperidone, other antipsychotics, carbamazepine and citalopram) have been ineffective or present unacceptable risks of adverse outcomes.

Antiepileptic drugs for the treatment of agitation and aggression in dementia: do they have a place in therapy?

Antiepileptic drugs (AEDs) are a class of medications that have received considerable attention as possible treatments for agitation and aggression in patients with dementia. This attention has been driven in equal measure by promising findings from limited trial and observational data and the desire to find treatments with improved tolerability. Their use, to date, has been largely confined to circumstances where first-line treatments have proven inadequate or are poorly tolerated. In recent years there has been some growth in the evidence base, and we can now make more informed recommendations regarding a number of older AEDs. Carbamazepine continues to have the best evidence to support its use, although the evidence base remains relatively small and concerns regarding tolerability limit its use. There is now more consistent evidence that valproate preparations should not be used for agitation and aggression in dementia. Despite a lack of high-quality data, some results have been reported for several newer medications, including levetiracetam, oxcarbazepine, gabapentin, topiramate and lamotrigine, and a number of these warrant further investigation. Recent findings and implications for clinical practice are discussed.

The efficacy and safety of newer anticonvulsants in patients with dementia

Anticonvulsants are a class of medications that have received considerable interest as possible treatments in patients with behavioural disturbances in dementia. The role of these medications for such a use remains controversial. The current paper reviews the published evidence surrounding the safety and efficacy (i.e. as a behavioural and cognitive treatment) of newer anticonvulsants in patients with dementia. A MEDLINE, International Pharmaceutical Abstracts, PsycINFO and clinicaltrials.gov search through to December 2011 was conducted for anticonvulsants that have received regulatory approval since 1996. Studies reporting behavioural or cognitive outcomes in patients with dementia were included. Nine trials involving only four medications met selection criteria and were included: levetiracetam (n = 4), oxcarbazepine (n = 1), topiramate (n = 2) and zonisamide (n = 2). Levetiracetam may have a role in the treatment of behavioural symptoms in dementia but study limitations substantially hinder the strength of such a recommendation. Oxcarbazepine and topiramate, based on limited data, do not appear to be effective treatments of behavioural symptoms in dementia. A lack of trials do not allow for conclusions to be made regarding zonisamide. From a cognitive standpoint, levetiracetam was the anticonvulsant most examined in patients with dementia, it appears to have less deleterious effects than some anticonvulsants. Limited data are available on the safety of these medications in elderly patients; however, studies completed thus far have demonstrated some adverse events that are more common or problematic with the use of these drugs in this patient population (i.e. somnolence, dizziness, hyponatraemia, weight loss).

Behavioral disturbance in dementia

Behavioral disturbances are frequently the most challenging manifestations of dementia and are exhibited in almost all people with dementia. Common behavioral disturbances can be grouped into four categories: mood disorders (e.g., depression, apathy, euphoria); sleep disorders (insomnia, hypersomnia, night-day reversal); psychotic symptoms (delusions and hallucinations); and agitation (e.g., pacing, wandering, sexual disinhibition, aggression). They are often persistent, greatly diminish quality of life of patients and their family caregivers, cause premature institutionalization, and pose a high economic burden on the patient, family, and society. Behavioral disturbances can be prevented and treated with a multifaceted approach that supports dignity and promotes comfort and quality of life of persons with dementia and their family members. Management involves prompt treatment of reversible factors and management of symptoms using primarily individualized nonpharmacological interventions. Pharmacological interventions need to be restricted to behavioral emergencies and for short-term treatment of behavioral disturbances that pose imminent danger to self or others.

A consensus statement for safety monitoring guidelines of treatments for major depressive disorder

OBJECTIVE

This paper aims to present an overview of screening and safety considerations for the treatment of clinical depressive disorders and make recommendations for safety monitoring.

METHOD

Data were sourced by a literature search using MEDLINE and a manual search of scientific journals to identify relevant articles. Draft guidelines were prepared and serially revised in an iterative manner until all co-authors gave final approval of content.

RESULTS

Screening and monitoring can detect medical causes of depression. Specific adverse effects associated with antidepressant treatments may be reduced or identified earlier by baseline screening and agent-specific monitoring after commencing treatment.

CONCLUSION

The adoption of safety monitoring guidelines when treating clinical depression is likely to improve overall physical health status and treatment outcome. It is important to implement these guidelines in the routine management of clinical depression.

Alzheimer's disease: diagnosis and treatment across the spectrum of disease severity

Alzheimer's disease exists along a spectrum, from early memory changes to functional dependence and death. Using a case illustration, we review the evaluation and diagnosis of mild cognitive impairment and the diagnosis and management of Alzheimer's disease at each stage, including the management of both cognitive and behavioral/psychiatric aspects of the disease and end-stage and end-of-life care.

Comparison of topiramate and risperidone for the treatment of behavioral disturbances of patients with Alzheimer disease: a double-blind, randomized clinical trial

INTRODUCTION

Behavioral disturbances are determining factors in handling patients with Alzheimer dementia. The current pharmacotherapy for behavioral symptoms associated with dementia is not satisfactory. Our goal was to compare a new anticonvulsant, topiramate, with a usually used medication, risperidone, for controlling behavioral disturbances of patients with Alzheimer dementia.

METHOD

Elderly patients with a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnosis of Alzheimer disease and significant behavioral disturbances were randomized to receive, for a period of 8 weeks, a flexible dose of either topiramate (25-50 mg/d) or risperidone (0.5-2 mg/d). Outcome measures were the Cohen-Mansfield Agitation Inventory, Neuropsychiatry Inventory parts 1 and 2, and the Clinical Global Impression.

RESULT

Forty-eight patients were randomized to treatment with either topiramate or risperidone, and 41 patients (21 of 25 in topiramate group and 20 of 23 in risperidone group) completed the trial. Both groups showed significant improvement in all outcome measures without important difference (Neuropsychiatry Inventory total score P < 0.531, Z = 0.62; Cohen-Mansfield Agitation Inventory P < 0.927, Z = 0.09; Clinical Global Impression, P < 0.654, Z = 0.48). There were no significant changes in the cognitive status of patients (assessed by Mini-Mental Status Examination) taking topiramate or risperidone during the trial.

CONCLUSION

Treatment with a low dose of topiramate (25-50 mg/d) demonstrated a comparable efficacy with risperidone in controlling behavioral disturbances of patients with Alzheimer dementia.

Clinical pharmacology of analgesics in old age and frailty

There is a high prevalence of pain in older people. Optimal assessment and management of pain in this population is challenging. The pharmacokinetics and pharmacodynamics of analgesic medications are affected by ageing and frailty, as well as by intercurrent medical conditions and their treatments. This review describes what is currently understood about the impacts of old age and frailty on the clinical pharmacology of commonly used analgesics, to provide a rational basis for the use of these medicines. In view of the wide age-related inter-individual variability in pharmacokinetics and pharmacodynamics of analgesic medications, monitoring of clinical response and adverse effects is essential to optimize pain control in older people.

Anticonvulsants in the treatment of aggression in the demented elderly: an update

INTRODUCTION

Complex psychopathological and behavioral symptoms, such as delusions and aggression against care providers, are often the primary cause of acute hospital admissions of elderly patients to emergency units and psychiatric departments. This issue resembles an interdisciplinary clinically highly relevant diagnostic and therapeutic challenge across many medical subjects and general practice. At least 50% of the dramatically growing number of patients with dementia exerts aggressive and agitated symptoms during the course of clinical progression, particularly at moderate clinical severity.

METHODS

Commonly used rating scales for agitation and aggression are reviewed and discussed. Furthermore, we focus in this article on benefits and limitations of all available data of anticonvulsants published in this specific indication, such as valproate, carbamazepine, oxcarbazepine, lamotrigine, gabapentin and topiramate.

RESULTS

To date, most positive and robust data are available for carbamazepine, however, pharmacokinetic interactions with secondary enzyme induction limit its use. Controlled data of valproate do not seem to support the use in this population. For oxcarbazepine only one controlled but negative trial is available. Positive small series and case reports have been reported for lamotrigine, gabapentin and topiramate.

CONCLUSION

So far, data of anticonvulsants in demented patients with behavioral disturbances are not convincing. Controlled clinical trials using specific, valid and psychometrically sound instruments of newer anticonvulsants with a better tolerability profile are mandatory to verify whether they can contribute as treatment option in this indication.

Use of gabapentin in the treatment of behavioural and psychological symptoms of dementia: a review of the evidence

Behavioural and psychological symptoms of dementia (BPSD) have been defined as a heterogeneous range of psychological reactions, psychiatric symptoms and behaviours that may be unsafe, disruptive and impair the care of a patient in a given environment. To date, there are no US FDA-approved drugs or clear standards of pharmacological care for the treatment of BPSD. The novel antiepileptic agent gabapentin is being increasingly considered for use in the geriatric population because of its relatively favourable safety profile compared with other classes of psychiatric medications. Gabapentin has been administered to several geriatric patients with bipolar disorder and patients with dementia. It has also been reported to be successful in the treatment of a 13-year-old boy with behavioural dyscontrol, a finding that suggested a possible role for gabapentin in the treatment of other behavioural disorders. The purpose of this review was to find evidence for the use of gabapentin in the treatment of BPSD. To this end, a search was performed for case reports, case series, controlled trials and reviews of gabapentin in the treatment of this condition. The key words 'dementia', 'Alzheimer's disease' and 'gabapentin' were used. Searches were performed in PubMed, PsycINFO, Ovid MEDLINE, Cochrane Library and ClinicalTrials.gov. The search revealed that there are limited data on the efficacy of gabapentin for BPSD in the form of 11 case reports, 3 case series and 1 retrospective chart review; no controlled studies appear to have been published to date on this topic. In most of the reviewed cases, gabapentin was reported to be a well tolerated and effective treatment for BPSD. However, two case reports in which gabapentin was used in the context of agitation in dementia with Lewy bodies questioned the appropriateness of gabapentin for all types of dementia-related agitation. The dearth of available data limits support for the off-label use of gabapentin for the treatment of BPSD. Furthermore, controlled studies should be conducted before gabapentin can be clinically indicated for the successful treatment of BPSD.

Molecular pharmacodynamics, clinical therapeutics, and pharmacokinetics of topiramate

Topiramate (TPM; TOPAMAX) is a broad-spectrum antiepileptic drug (AED) that is approved in many world markets for preventing or reducing the frequency of epileptic seizures (as monotherapy or adjunctive therapy), and for the prophylaxis of migraine. TPM, a sulfamate derivative of the naturally occurring sugar D-fructose, possesses several pharmacodynamic properties that may contribute to its clinically useful attributes, and to its observed adverse effects. The sulfamate moiety is essential, but not sufficient, for its pharmacodynamic properties. In this review, we discuss the known pharmacodynamic and pharmacokinetic properties of TPM, as well as its various clinically beneficial and adverse effects.