Patients' versus caregivers' report of poor memory in relation to dementia and tested abilities

Informant-reported cognitive symptoms that predict amnestic mild cognitive impairment

BACKGROUND

Differentiating amnestic mild cognitive impairment (aMCI) from normal cognition is difficult in clinical settings. Self-reported and informant-reported memory complaints occur often in both clinical groups, which then necessitates the use of a comprehensive neuropsychological examination to make a differential diagnosis. However, the ability to identify cognitive symptoms that are predictive of aMCI through informant-based information may provide some clinical utility in accurately identifying individuals who are at risk for developing Alzheimer's disease (AD).

METHODS

The current study utilized a case-control design using data from an ongoing validation study of the Alzheimer's Questionnaire (AQ), an informant-based dementia assessment. Data from 51 cognitively normal (CN) individuals participating in a brain donation program and 47 aMCI individuals seen in a neurology practice at the same institute were analyzed to determine which AQ items differentiated aMCI from CN individuals.

RESULTS

Forward stepwise multiple logistic regression analysis which controlled for age and education showed that 4 AQ items were strong indicators of aMCI which included: repetition of statements and/or questions [OR 13.20 (3.02, 57.66)]; trouble knowing the day, date, month, year, and time [OR 17.97 (2.63, 122.77)]; difficulty managing finances [OR 11.60 (2.10, 63.99)]; and decreased sense of direction [OR 5.84 (1.09, 31.30)].

CONCLUSIONS

Overall, these data indicate that certain informant-reported cognitive symptoms may help clinicians differentiate individuals with aMCI from those with normal cognition. Items pertaining to repetition of statements, orientation, ability to manage finances, and visuospatial disorientation had high discriminatory power.

Validation of a memory inventory for the assessment of awareness of memory deficits in Alzheimer's disease in Chinese elderly

BACKGROUND

This paper describes the development and validation of the Memory Inventory for Chinese (MIC), for measuring the awareness of memory deficits in the Chinese population with Alzheimer's disease (AD).

METHODS

A combination of qualitative and quantitative approaches was adopted. The MIC was developed with focus group discussion and pilot testing. It has a patient and a caregiver version. A consecutive series of 79 new out-patients with the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorder Association (NINCDS-ADRDA) criteria of probable and possible AD and 20 non-demented elderly subjects were recruited.

RESULTS

A high internal consistency was found, with Cronbach alpha of 0.89 for the patient version and 0.90 for the caregiver version of MIC. The inter-rater reliability was satisfactory. For validity assessment, the caregiver score of the MIC correlated significantly with cognitive score of the subject as assessed by the Mini-Mental State Examination (rp = -0.37; p < 0.01). The Memory Deficit Awareness Score, calculated by subtracting the patient score from the caregiver score, correlated significantly with clinician ratings of awareness of memory impairment (rs = -0.67; p < 0.01).

CONCLUSIONS

The MIC appears to be a culturally appropriate and valid instrument for the measurement of awareness of memory deficits in Chinese patients with AD. Potential applications of the MIC should be further explored in other subtypes of dementia and in prospective studies.

Role of valproate across the ages. Treatment of epilepsy in children

In June 2005 a team of experts participated in a workshop with the objective of reaching agreement on the place of valproate use in the treatment of paediatric epilepsy patients. A general "consensus of the meeting" was that the initiation of antiepileptic drug (AED) treatment should be based on a seizure-syndromic approach in children. Participants of the meeting also agreed that valproate is currently the AED with the broadest spectrum across all types of seizures and syndromes. Its superiority has been shown over almost 40 years of clinical experience. The best results are seen in idiopathic generalized epilepsy with or without photosensitivity, idiopathic focal and symptomatic generalized tonic-clonic seizures (GTCS). Evidence supports the use of valproate, ethosuximide and lamotrigine in absence epilepsies and the use of carbamazepine, lamotrigine, oxcarbazepine, phenytoin, topiramate, valproate and phenobarbital for primary GTCS. For new AEDs trials have been undertaken to define their therapeutic role but studies comparing their role to 'old' broad-spectrum drugs in specific syndromes are missing. Experts concluded that intravenous (i.v.) valproate is a useful agent in the treatment of non-convulsive status epilepticus (SE). There is an easy transition to oral treatment following i.v. valproate use. The discussion also concluded that, despite the lack of studies, valproate is an interesting, underutilized alternative in convulsive SE but more controlled studies are needed. The side effects of valproate use are well documented. Its effect on cognition and behaviour is more favourable than many of the other AEDs which is an important consideration in children. Overall, the clinical consensus of the meeting was that valproate's well established therapeutic properties far outweigh the negative side effects. Contraindication or withdrawal should be assessed individually.

Seizures of idiopathic generalized epilepsies

Idiopathic generalized epilepsies (IGEs) comprise at least 40% of epilepsies in the United States, 20% in Mexico, and 8% in Central America. Here, we review seizure phenotypes across IGE syndromes, their response to treatment and advances in molecular genetics that influence nosology. Our review included the Medline database from 1945 to 2005 and our prospectively collected Genetic Epilepsy Studies (GENESS) Consortium database. Generalized seizures occur with different and similar semiologies, frequencies, and patterns, ages at onset, and outcomes in different IGEs, suggesting common neuroanatomical pathways for seizure phenotypes. However, the same seizure phenotypes respond differently to the same treatments in different IGEs, suggesting different molecular defects across syndromes. De novo mutations in SCN1A in sporadic Dravet syndrome and germline mutations in SCN1A, SCN1B, and SCN2A in generalized epilepsies with febrile seizures plus have unraveled the heterogenous myoclonic epilepsies of infancy and early childhood. Mutations in GABRA1, GABRG2, and GABRB3 are associated with absence seizures, while mutations in CLCN2 and myoclonin/EFHC1 substantiate juvenile myoclonic epilepsy as a clinical entity. Refined understanding of seizure phenotypes, their semiology, frequencies, and patterns together with the identification of molecular lesions in IGEs continue to accelerate the development of molecular epileptology.

Metacognitive deficits in frontotemporal dementia

OBJECTIVES

To investigate whether metacognitive impairments in self-awareness and self-monitoring occur in patients with frontotemporal dementia (FTD), particularly among those with prominent social and dysexecutive impairments.

METHODS

Patients diagnosed with FTD were divided by clinical subtype (social-dysexecutive (n = 12) aphasic (n = 15), and constituent subgroups of progressive non-fluent aphasia and semantic dementia) and compared with subjects with probable Alzheimer's disease (AD, n = 11) and age-matched healthy controls (n = 11). All subjects completed comprehensive behavioural ratings scales, which were compared with caregiver ratings. Subjects also rated their test performances in verbal associative fluency, word list learning, and memory task with comparisons made between actual and judged performance levels.

RESULTS

The FTD sample as a whole showed significantly less behavioural self-awareness and self-knowledge than the AD and healthy control samples. FTD patients with prominent social and dysexecutive impairments demonstrated the most extensive loss of self-awareness and self-knowledge, significantly overrating themselves in multiple social, emotional, and cognitive domains, and failing to acknowledge that any behavioural change had occurred in most areas. The remaining clinical samples showed select and minimal discrepancies. All clinical groups were significantly unaware of their apathy levels. Most FTD patients judged episodic cognitive test performance adequately, with partial difficulties observed in the socially impaired and progressive non-fluent aphasia subgroups.

CONCLUSIONS

FTD patients, particularly those with prominent social and dysexecutive impairments, exhibit profound metacognitive anosognosia that may represent a loss of self-awareness, self-monitoring, and self-knowledge, likely related to significant prefrontal pathophysiology. Other FTD clinical groups and AD patients showed less pervasive and more select metacognitive deficiencies.

Seizure Aggravation in Idiopathic Generalized Epilepsies

Seizures in the idiopathic generalized epilepsies (IGEs) usually remit completely with antiepileptic drugs (AEDs). Occasionally, however, they may be aggravated by AEDs. Before attributing exacerbation of seizures to an AED, alternative explanations need to be excluded. These include natural fluctuation of seizures, irregular compliance, maladjustment to the disease, comorbid illness, and development of tolerance. Aggravation may be due to a paradoxical reaction or drug-induced encephalopathy, sedative effects, or inappropriate use of a drug; and this need to be established, as it will guide management. An important caveat is that most data on aggravation of generalized seizures are based on anecdotal case reports or case series. Whether considering efficacy or aggravation, the interpretation of data from uncontrolled studies and case reports must be treated with caution. In practice, despite the fact that clear evidence is lacking, the possibility of seizure aggravation must be considered when treating people with IGEs. Predictive factors for seizure aggravation in a particular patient with a specific drug are yet to be fully defined. It is paramount to classify seizure type correctly in all patients. If this is not possible, a broad-spectrum AED should be used. Drugs that modulate Na+-channels and GABAergic drugs seem to be more prone to aggravating seizures, and therefore are best avoided in the initial management of IGE. Further studies are required to elucidate this phenomenon in full. It is interesting to speculate that paradoxical responses to AEDs may have pharmacogenetic value, serving as tools for a more precise and useful characterization of the epilepsies.

Evidence-based Treatment of Idiopathic Generalized Epilepsies with New Antiepileptic Drugs

With the introduction of over ten new antiepileptic drugs (AEDs) since 1993, the hope has been that at least some of these agents would be useful for not just partial seizures, but also for the primary generalized seizures of the idiopathic generalized epilepsies (IGE). The development of evidence-based treatment guidelines in the IGE, however, faces a number of challenges, particularly after an antiepileptic drug (AED) receives approval for one indication. The majority of patients with IGE are controlled with first-line therapy if appropriately selected. Case reports or series typically appear with use in refractory patients, but these studies lack the rigor to allow formulation of guidelines. Still we are beginning to see some good class I and II data to support use of selected second-generation AEDs. It is postulated that lamotrigine (LTG), levetiracetam (LEV), topiramate (TPM), and zonisamide (ZSM) may have efficacy for a broad spectrum of seizure types including those of IGE. At the present time good class I and II evidence exists to support the use of LTG for typical absence, LEV for idiopathic myoclonic seizures, and TPM for primary generalized tonic-clonic seizures, even though only TPM has FDA approval for primary generalized seizures. This article examines the available rigorous evidence that can support these uses and also discusses some selected other reports that suggest a spectrum of efficacy for these new agents.

Efficacy and safety of lamotrigine in pediatric patients

Accumulating data suggest that lamotrigine, which has been available for adult use in epilepsy for more than a decade in clinical practice, also confers effective, well-tolerated control of a range of childhood epilepsies. Lamotrigine is currently approved for the treatment of epilepsy by regulatory authorities in 93 countries, more than 70 of which have approved its use in pediatric patients on the basis of data from well-controlled clinical trials. The controlled clinical trials data have been supplemented over the years by clinical practice data, primarily from uncontrolled studies, confirming or demonstrating additional efficacy of lamotrigine for a range of seizure types. This article reviews the data from well-controlled clinical trials and studies conducted in clinical practice to present an updated perspective on the efficacy and safety of lamotrigine in pediatric patients.