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Epileptic seizures are increasingly recognized as part of the clinical phenotype of patients with Alzheimer’s disease (AD). However, the evidence base on which to make treatment decisions for such patients is slim, there being no clear recommendation based on systematic review of the few existing studies of anti-seizure drugs in AD patients. Here the authors examine the potential implications for the treatment of seizures in AD of the results of the recently published SANAD II pragmatic study, which examined the effectiveness of levetiracetam, zonisamide, or lamotrigine in newly diagnosed focal epilepsy, and of valproate and levetiracetam in generalized and unclassifiable epilepsy.

Over 20 years ago, Charles Warlow, the founding editor ofPractical Neurology, offered a copy of his stroke textbook to anyone diagnosing an intracranial arteriovenous malformation by auscultation of the skull alone. This article examines the possible diagnostic value of intracranial bruit in terms of the 2×2 contingency table for diagnostic tests and recounts an historical case.

SUMMARYPsychiatrists may be daunted by the prospect of undertaking a neurological examination. In this article we briefly review the neurological signs that may be seen in the context of some common neurological disorders of cognition and movement which may present with neurobehavioural symptoms and therefore may be seen initially by psychiatrists. This approach emphasises that neurological examination is not simply an operationalised procedure but an interpretative process. We propose a minimum neurological examination suitable for use by psychiatrists. Many of the signs included are relatively simple to observe or elicit, require no special equipment, and the examination techniques involved are easy to master.

Background The Mini-Addenbrooke’s Cognitive Examination (MACE) is a recently described brief cognitive screening instrument. Objective To examine the test accuracy of MACE for the identification of dementia and mild cognitive impairment (MCI) in a cohort of older patients assessed in a neurology-led dedicated cognitive disorders clinic. Methods Cross-sectional assessment of consecutive patients with MACE was performed independent of the reference standard diagnosis based on clinical interview of patient and, where possible, informant and structural brain imaging, and applying standard clinical diagnostic criteria for dementia and MCI. Various test accuracy metrics were examined at two MACE cut-offs ( ≤ 25/30 and ≤ 21/30), comparing the whole patient cohort with those aged ≥ 65 or ≥ 75 years, hence at different disease prevalences. Results Dependent upon the chosen cut-off, MACE was either very sensitive or very specific for the identification of any cognitive impairment in the older patient cohorts with increased disease prevalence. However, at both cut-offs the positive predictive values and post-test odds increased in the older patient cohorts. At the more sensitive cut-off, improvements in some new unitary test metrics were also seen. Conclusion MACE is a valid instrument for identification of cognitive impairment in older people. Test accuracy metrics may differ with disease prevalence.

Many patients referred to cognitive disorders clinics are not found to have evidence of any neurological disorder(s) to account for their symptoms. Many demonstrate incongruence between their subjective cognitive symptoms and preserved social and occupational functions. The term ‘functional cognitive disorders’ (FCD) has been used to denote this diagnostic category. This article aims to review the current state of knowledge regarding FCD. Studies of FCD are in their infancy, but available evidence suggests positive diagnosis may be made based on typical clinical profiles, including language discourse and simple clinical signs. Concurrent mood disorder and sleep disturbance are common, as well as other functional disorders. Pathogenesis is yet to be determined, but a disorder of metamemory has been suggested.

Objectives: To examine the diagnostic utility of the 'attended alone' (AA) and 'attended with' (AW) signs for the diagnosis of major and minor neurocognitive disorder. Methods: Consecutive unselected new outpatient referrals (N = 1209) to a dedicated cognitive disorders clinic over a 5-year period (2015-2019 inclusive) were observed for the AA and AW signs. Criterion diagnoses were by usual clinic assessment using standard (DSM-5) diagnostic criteria. Results: AW proved to be very sensitive for the identification of major and minor neurocognitive disorder but with generally low positive predictive values. In the subgroup of patients attending with more than one informant, the AW2+ sign, positive predictive value was higher and likewise with increasing patient age where the prevalence of AW was higher. Diagnostic utility of AW and AA was independent of patient gender. Conclusion: AW and AA are easily observed and categorized signs. AW has a high sensitivity for cognitive impairment while AA has a high positive predictive value for its absence.

This chapter considers the differential diagnosis of TGA. Key considerations include cerebrovascular disease (TIA, stroke), epilepsy (transient epileptic amnesia, TEA), and psychological causes, as well as a variety of other causes of transient amnesia (migraine, drugs, hypoglycaemia, head injury). On clinical grounds alone, it is often possible to distinguish TGA from other causes of transient amnesia.

Cognitive screening instruments (CSIs) for dementia and mild cognitive impairment are usually characterized in terms of measures of discrimination such as sensitivity, specificity, and likelihood ratios, but these CSIs also have limitations. Objective: The aim of this study was to calculate various measures of test limitation for commonly used CSIs, namely, misclassification rate (MR), net harm/net benefit ratio (H/B), and the likelihood to be diagnosed or misdiagnosed (LDM). Methods: Data from several previously reported pragmatic test accuracy studies of CSIs (Mini-Mental State Examination, the Montreal Cognitive Assessment, Mini-Addenbrooke’s Cognitive Examination, Six-item Cognitive Impairment Test, informant Ascertain Dementia 8, Test Your Memory test, and Free-Cog) undertaken in a single clinic were reanalyzed to calculate and compare MR, H/B, and the LDM for each test. Results: Some CSIs with very high sensitivity but low specificity for dementia fared poorly on measures of limitation, with high MRs, low H/B, and low LDM; some had likelihoods favoring misdiagnosis over diagnosis. Tests with a better balance of sensitivity and specificity fared better on measures of limitation. Conclusions: When deciding which CSI to administer, measures of test limitation as well as measures of test discrimination should be considered. Identification of CSIs with high MR, low H/B, and low LDM, may have implications for their use in clinical practice. RESUMO Os instrumentos de rastreio cognitivo (IRCs) para demência e comprometimento cognitivo leve são geralmente caracterizados em termos de medidas de discriminação, como sensibilidade, especificidade e razões de probabilidade, mas esses IRCs também têm limitações. Objetivo: Calcular várias medidas de limitação de testes para IRC comumente usados, a saber: taxa de classificação incorreta; relação entre dano líquido e benefício líquido; e probabilidade de diagnóstico ou diagnóstico incorreto. Métodos: Os dados de vários estudos de precisão de teste pragmático de IRC relatados anteriormente (MMSE, MoCA, MACE, 6CIT, AD8, TYM, Free-Cog) e realizados em uma única clínica foram reanalisados para calcular e comparar a taxa de classificação incorreta, o dano líquido para a relação de benefício líquido e a probabilidade de diagnóstico ou diagnóstico incorreto para cada teste. Resultados: Alguns IRC com sensibilidade muito alta, mas baixa especificidade para demência, tiveram desempenho ruim em medidas de limitação, com altas taxas de classificação incorreta, baixo prejuízo líquido para relações de benefício líquido e baixa probabilidade de diagnóstico ou diagnóstico incorreto; alguns tinham probabilidades de favorecer o diagnóstico incorreto ao invés do diagnóstico. Testes com melhor equilíbrio de sensibilidade e especificidade saíram-se melhor nas medidas de limitação. Conclusões: Ao decidir qual IRC administrar, as medidas de limitação, bem como as medidas de discriminação do teste, devem ser consideradas. A identificação de IRC com alta taxa de classificação incorreta, baixa relação de prejuízo e benefício e baixa probabilidade de diagnóstico ou diagnóstico incorreto pode ter implicações para seu uso na prática clínica.

Diagnostic and screening tests may have risks such as misdiagnosis, as well as the potential benefits of correct diagnosis. Effective communication of this risk to both clinicians and patients can be problematic. The purpose of this study was to develop a metric called the “efficiency index” (EI), defined as the ratio of test accuracy and inaccuracy, to evaluate screening tests for dementia. This measure was compared with a previously described “likelihood to be diagnosed or misdiagnosed” (LDM), also based on “numbers needed” metrics. Datasets from prospective pragmatic test accuracy studies examining four brief cognitive screening instruments (Mini-Mental State Examination, Montreal Cognitive Assessment, Mini-Addenbrooke’s Cognitive Examination (MACE), and Free-Cog) were analysed to calculate values for EI and LDM, and to examine their variation with test cut-off for MACE and dementia prevalence. EI values were also calculated using a modification of McGee’s heuristic for the simplification of likelihood ratios to estimate percentage change in diagnostic probability. The findings indicate that EI is easier to calculate than LDM and, unlike LDM, may be classified either qualitatively or quantitatively in a manner similar to likelihood ratios. EI shows the utility or inutility of diagnostic and screening tests, illustrating the inevitable trade-off between diagnosis and misdiagnosis. It may be a useful metric to communicate risk in a way that is easily intelligible for both clinicians and patients.

Remote systems of care have become necessary in the COVID-19 pandemic This study examined the feasibility of telephone screening of cognitive function in patients with epilepsy to assess the frequency of, and factors associated with, cognitive impairment in these patients Administration of the Six-item Cognitive Impairment Test, a brief cognitive screening instrument that eschews visuospatial or visuoperceptual tests, proved acceptable to patients with epilepsy

Aim: To extend use of the recently described ‘likelihood to be diagnosed or misdiagnosed’ (LDM) metric for test accuracy studies through application to recent meta-analytic data of commonly used cognitive screening instruments. Methods: Raw data (true positives and negatives, false positives and negatives) were extracted from meta-analyses (minimum 5 studies or 1000 patients), from which LDM was calculated. LDM values were compared with those previously reported for single test accuracy studies. Results: LDM values for diagnosis of dementia ranged from around two to seven, and for diagnosis of mild cognitive impairment from two to three. LDM values based on meta-analytic data were larger than those reported for individual studies. Conclusion: LDM is an easily calculated and potentially useful unitary, global metric for test accuracy studies.

This review presents a critical appraisal of epileptic seizures in common neurodegenerative diseases related to proteinopathy, including Alzheimer’s disease (AD), dementia with Lewy bodies, frontotemporal dementias, and prion diseases. Studies on prevalence, seizure type, and treatment are reviewed, and tentative management recommendations made. Gaps in the evidence base are indicated. Epidemiological studies show that patients with AD are at increased risk of epileptic seizures. Cumulative seizure frequency of > 10% is reported and may be higher if subtle seizure features are sought by means of a proforma. Seizures may be associated with more rapid cognitive decline. The evidence base for treatment with anti-epileptic drugs in AD is weak, and potential benefits must be weighed against the risk of adverse events. Animal studies indicate that the abnormal protein species, amyloid peptides and tau, accumulating in AD brain may be implicated in epileptogenesis. Fewer data are available for the other neurodegenerative diseases, meaning that seizure treatment is largely empirical. Epileptic seizures may be an integral part of many proteinopathies of the brain, rather than epiphenomena. Symptomatic treatment of seizures is currently largely empirical. The hope for the future is that seizures, like cognitive impairment, may be susceptible to disease-modifying treatments targeting aberrant protein species.

An increasing proportion of cognitive difficulties are recognized to have a functional cause, the chief clinical indicator of which is internal inconsistency. When these symptoms are impairing or distressing, and not better explained by other disorders, this can be conceptualized as a cognitive variant of functional neurological disorder, termed functional cognitive disorder (FCD). FCD is likely very common in clinical practice but may be under-diagnosed. Clinicians in many settings make liberal use of the descriptive term mild cognitive impairment (MCI) for those with cognitive difficulties not impairing enough to qualify as dementia. However, MCI is an aetiology-neutral description, which therefore includes patients with a wide range of underlying causes. Consequently, a proportion of MCI cases are due to non-neurodegenerative processes, including FCD. Indeed, significant numbers of patients diagnosed with MCI do not ‘convert’ to dementia. The lack of diagnostic specificity for MCI ‘non-progressors’ is a weakness inherent in framing MCI primarily within a deterministic neurodegenerative pathway. It is recognized that depression, anxiety and behavioural changes can represent a prodrome to neurodegeneration; empirical data are required to explore whether the same might hold for subsets of individuals with FCD. Clinicians and researchers can improve study efficacy and patient outcomes by viewing MCI as a descriptive term with a wide differential diagnosis, including potentially reversible components such as FCD. We present a preliminary definition of functional neurological disorder–cognitive subtype, explain its position in relation to other cognitive diagnoses and emerging biomarkers, highlight clinical features that can lead to positive diagnosis (as opposed to a diagnosis of exclusion), and red flags that should prompt consideration of alternative diagnoses. In the research setting, positive identifiers of FCD will enhance our recognition of individuals who are not in a neurodegenerative prodrome, while greater use of this diagnosis in clinical practice will facilitate personalized interventions.

Background/Aims: Canonical definitions of the dementia construct encompass deficits in both cognition and function, but most screening instruments for possible dementia address only cognitive abilities. Free-Cog is a recently described brief screening instrument for dementia designed to address not only cognitive but also functional abilities. Methods: A pragmatic test accuracy study of Free-Cog was undertaken in consecutive patients seen over 1 year in a secondary care setting. The performance of Free-Cog for diagnosis of dementia and mild cognitive impairment (MCI) was compared to that of Mini-Addenbrooke’s Cognitive Examination (MACE). Results: In a cohort of 141 patients (prevalence of dementia and MCI 11 and 32%, respectively) both Free-Cog and MACE were quick and easy to use and acceptable to patients. Both tests had high sensitivity (1.00) and large effect sizes (Cohen’s d) for diagnosis of dementia, but Free-Cog was more specific. For diagnosis of MCI, Free-Cog lacked sensitivity (0.58) but was specific (0.81), whereas MACE was sensitive (0.91) but not specific (0.35). Weighted comparison suggested equivalence for dementia diagnosis but a net benefit for MACE regarding MCI diagnosis. Conclusion: Free-Cog is an acceptable and accurate test for dementia screening in a dedicated cognitive disorders clinic, but it appears less sensitive than MACE for the identification of MCI.

The spinal cord is subject to numerous pathological processes which may be intrinsic (intramedullary) and/or extrinsic (extramedullary) to the cord. Many diseases can affect the spinal cord. Those of particular note include spondylotic myelopathy, multiple sclerosis, transverse myelitis, subacute combined degeneration of the cord, genetic and vascular disorders, syringomyelia, injury/trauma, motor neuron disease, and cancer—the most common spinal cord tumours are metastasis, astrocytoma, ependymoma, lymphoma. Specific medical and surgical treatments are determined by the particular cause of myelopathy. These may arrest progression, but function that has been lost may not recover fully. Prognosis of acute cord compression is directly related to the time delay between symptom onset and relief of compression. Chronic disability as a consequence of spinal cord disease requires intensive neurorehabilitation.

Aim: To undertake a diagnostic test accuracy study of the Mini-Mental State Examination (MMSE) administered in primary care to patients who were subsequently referred to a cognitive disorders clinic in secondary care (n = 72). Methods: MMSE scores from primary care were cross-classified with reference standard diagnoses made in secondary care, blind to MMSE score, in order to calculate standard measures of discrimination (including sensitivity and specificity, positive and negative predictive values). Results: MMSE showed poor sensitivity (0.64) but better specificity (0.80) for diagnosis of any cognitive impairment at the index paper specified cut-off, with little additional benefit using a more stringent cut-off. Conclusion: These data suggest MMSE is not suitable for screening for cognitive impairment in the low prevalence setting of primary care.

Age is a key risk factor for cognitive impairment and dementia, although cognitive complaints may also occur in younger people. Here, the authors re-analyse data from several pragmatic diagnostic test accuracy studies examining various short cognitive screening instruments (CSIs) in a secondary-care, neurology-led, cognitive disorders clinic and establish whether any CSI tests are more favourable in the older age group.

This chapter examines pragmatic studies of sleep disorder screeners. Their use in the cognitive clinic may be indicated if sleep disturbance is suspected as a factor in cognitive impairment. Their unitary metrics suggest, unsurprisingly, limitations for dementia diagnosis, presumably because they do not directly examine cognitive function, but they may identify individuals who might benefit from interventions to improve sleep quality.

This chapter examines combinations of various screeners described individually in previous chapters. As for the combination of cognitive screeners, use of simple logical rules, in series and in parallel, improves specificity and sensitivity respectively. For some of the combinations examined, particularly the combination of functional and cognitive screeners, the unitary metrics are encouraging for the identification of cognitive impairment.

In this special issue of Diagnostics, expert contributors have produced up-to-date research studies and reviews on various topics related to the diagnosis of dementia and cognitive impairment. The methods of the assessments discussed extend from simple neurological signs, which may be elicited in the clinical encounter, through cognitive screening instruments, to sophisticated analyses of neuroimaging and cerebrospinal fluid biomarkers of disease. It is hoped that these various methods may facilitate earlier diagnosis of dementia and its subtypes, and provide differential diagnosis of depression and functional cognitive disorders, as a prelude to meaningful interventions.

Introduction: Alzheimer's disease may be associated with both clinical and subclinical epileptic seizure activity. Once regarded as an epiphenomenon, epileptiform activity may, in fact, be an integral part of the Alzheimer's phenotype, and may be not only a symptomatic therapeutic target but also a possible mechanism to retard or prevent disease progression. Areas covered: The authors review clinical research articles with a focus on the semiology, epidemiology, and treatment of seizures in Alzheimer's disease, and also look at some experimental animal model studies which have informed clinical thinking on seizure aetiopathogenesis. The evidence base for treatment decisions is sparse. A brief overview of the clinical assessment of Alzheimer's disease patients considering relevant differential diagnoses and diagnostic pitfalls is presented. Expert opinion: Studies of epileptic seizures in Alzheimer's disease have become more frequent over the last 5-10 years. Understanding of seizure semiology, epidemiology, and possible pathogenesis has increased. However, the optimal management of seizures in this context remains unknown, largely due to the paucity of studies sufficient to examine this question. Clearly, such studies will be required, not only to inform clinicians about symptomatic control of seizures in Alzheimer's disease but also to investigate whether this might impact on disease progression.

Many cognitive screening instruments are available to assess patients with cognitive symptoms in whom a diagnosis of dementia or mild cognitive impairment is being considered. Most are quantitative scales with specified cut-off values. In contrast, the cognitive disorders examination or Codex is a two-step decision tree which incorporates components from the Mini-Mental State Examination (MMSE) (three word recall, spatial orientation) along with a simplified clock drawing test to produce categorical outcomes defining the probability of dementia diagnosis and, by implication, directing clinician response (reassurance, monitoring, further investigation, immediate treatment). Codex has been shown to have high sensitivity and specificity for dementia diagnosis but is less sensitive for the diagnosis of mild cognitive impairment (MCI). We examined minor modifications to the Codex decision tree to try to improve its sensitivity for the diagnosis of MCI, based on data extracted from studies of two other cognitive screening instruments, the Montreal Cognitive Assessment and Free-Cog, which are more stringent than MMSE in their tests of delayed recall. Neither modification proved of diagnostic value for mild cognitive impairment. Possible explanations for this failure are considered.

The definition of test cut-offs is a critical determinant of many paired and unitary measures of diagnostic or screening test accuracy, such as sensitivity and specificity, positive and negative predictive values, and correct classification accuracy. Revision of test cut-offs from those defined in index studies is frowned upon as a potential source of bias, seemingly accepting any biases present in the index study, for example related to sample bias. Data from a large pragmatic test accuracy study examining the Mini-Addenbrooke&rsquo, s Cognitive Examination (MACE) were interrogated to determine optimal test cut-offs for the diagnosis of dementia and mild cognitive impairment (MCI) using either the maximal Youden index or the maximal correct classification accuracy. Receiver operating characteristic (ROC) and precision recall (PR) curves for dementia and MCI were also plotted, and MACE predictive values across a range of disease prevalences were calculated. Optimal cut-offs were found to be a point lower than those defined in the index study. MACE had good metrics for the area under the ROC curve and for the effect size (Cohen&rsquo, s d) for both dementia and MCI diagnosis, but PR curves suggested the superiority for MCI diagnosis. MACE had high negative predictive value at all prevalences, suggesting that a MACE test score above either cut-off excludes dementia and MCI in any setting.

Epileptic seizures have been described as one feature of prion diseases, but are an unusual clinical presentation. The aim of this narrative Review was to summarize current knowledge of epileptic seizures in the various forms of prion diseases, from a clinical perspective. Examination of the published literature identified no systematic studies; the evidence base is largely anecdotal, consisting mainly of case studies and small case series. Hence, uncertainty prevails as to seizure frequency, semiology, treatment, and pathogenesis in prion diseases. Seizures probably occur in around 10% of sporadic cases but less frequently in iatrogenic and familial forms, with the possible exception of the E200K mutation. The literature suggests a predominance of focal motor and nonconvulsive status epilepticus. Electroencephalographic accompaniments include periodic lateralized or generalized periodic epileptiform discharges (PLEDs, GPEDs), sometimes predating the more typical periodic sharp wave complexes. There are no convincing accounts of successful antiepileptic drug therapy. The underlying mechanisms of epileptogenesis in prion diseases may include loss of cellular prion protein function (PrPc) and aggregation of abnormally folded prion protein (PrPSc). The need for systematic studies and clinical trials to expand the evidence base surrounding epilepsy and prion diseases is evident.

Aim: To measure the frequency of scoring and reporting errors in cognitive screening instruments administered in the primary care setting in consecutive referrals to a dedicated secondary care memory clinic. Methods: Using a simple ad hoc classification, referral letters from primary care mentioning cognitive screening instrument use were classified as: unequivocal, incorrect/ambiguous or incomplete. Results: Overall, reported test scores were either ambiguous/incorrect or incomplete in 23% of cases, with higher individual frequencies for two screening instruments recommended for use in primary care, the Six-item Cognitive Impairment Test (26%) and the General Practitioner Assessment of Cognition (32%). Conclusion: Errors are not infrequent in the scoring and reporting of cognitive screening instruments administered in primary care. More training in their correct use and scoring is required.

The differential diagnosis of progressive neurodegenerative disorders may sometimes be challenging, despite longitudinal assessment and access to traditional modalities of structural and functional neuroimaging. In this article, the authors describe a patient tentatively diagnosed with corticobasal syndrome in whom investigation with cerebrospinal fluid biomarkers led to diagnostic revision and new therapeutic options.

A patient presented with fulminant pulmonary oedema and required acute intubation and ventilation. There was no history of a prior cardiac disorder. As he was weaned from sedation, following stabilisation of his pulmonary status, neurological signs suggestive of brainstem dysfunction became apparent. Investigations showed infarcts in the posterior cerebral circulation secondary to a vertebral artery dissection. Neurogenic pulmonary oedema needs to be considered in any patient with fulminant pulmonary oedema without overt evidence or history of cardiac disease.

The clinical syndromes of frontotemporal dementia are clinically and neuropathologically heterogeneous, but processes such as neuroinflammation may be common across the disease spectrum. We investigated how neuroinflammation relates to the aggregation of Tau and TDP-43 in frontotemporal dementia, and to the heterogeneity of clinical disease. We used positron emission tomography in vivo with (a) [11C]PK-11195, a marker of activated microglia and a proxy index of neuroinflammation, and (b) [18F]AV-1451, a radioligand with increased binding to pathologically affected regions in tauopathies and diseases associated with TDP-43 protein aggregation, and which is used as a surrogate marker of non-β-amyloid protein aggregation. We assessed 31 patients with frontotemporal dementia (10 with behavioural variant frontotemporal dementia, 11 with the semantic variant of primary progressive aphasia and 10 with the non-fluent variant of primary progressive aphasia), 28 of whom underwent both [18F]AV-1451 and [11C]PK-11195 PET, and matched controls (14 for [18F]AV-1451 and 15 for [11C]PK-11195). We used univariate region-of-interest analyses, and multivariate analysis of the distribution of binding that explicitly control for individual differences in ligand affinity for TDP-43 and different Tau isoforms. We found differences between patients and controls in frontotemporal regions for both neuroinflammation and protein aggregation, and a strong positive correlation between these two processes in all disease groups. Despite this regional co-localisation, the multivariate distribution of [11C]PK-11195 binding related better to clinical heterogeneity than did the distribution of [18F]AV-1451: distinct spatial modes of neuroinflammation were associated with different frontotemporal dementia syndromes and supported accurate group classification of participants. These in vivo findings indicate a close association between neuroinflammation and protein aggregation in frontotemporal dementia. The inflammatory component may be important in shaping the clinical and neuropathological patterns of the diverse clinical syndromes of frontotemporal dementia.

This chapter examines the presentation of the results of diagnostic test accuracy studies in terms of specific measures of discrimination and comparison. To exemplify the utility of these measures, studies of some of the key investigations currently used in dementia diagnosis, namely cognitive screening instruments (both performance based and informant based) and biomarkers based on functional neuroimaging and cerebrospinal fluid neurochemistry, are used.

Aim: To examine features associated with functional cognitive disorders (FCDs) compared with neurological cognitive disorders (dementia, mild cognitive impairment, transient amnesias) in consecutive patients referred to a secondary care cognitive disorders clinic. Methods: Patients diagnosed with either neurological cognitive disorder or FCD were compared by demographic (age, gender, handedness, referral source) and clinical features (family history of dementia, clinical signs, Likert screening measure of subjective memory complaint, mini-Addenbrooke's Cognitive Examination). Results: Patients diagnosed with FCD were younger than those with neurological cognitive disorders, and more likely to attend alone, have a family history of dementia and be categorized as positive for subjective memory complaint. Conclusion: These data suggest features which may be helpful in making a positive diagnosis of FCD and differentiating from neurological cognitive disorders.

Introduction: Short‐form versions of the Montreal Cognitive Assessment (SF‐MoCA) are increasingly used to screen for dementia in research and practice. We sought to collate evidence on the accuracy of SF‐MoCAs and to externally validate these assessment tools. Methods: We performed systematic literature searching across multidisciplinary electronic literature databases, collating information on the content and accuracy of all published SF‐MoCAs. We then validated all the SF‐MoCAs against clinical diagnosis using independent stroke (n = 787) and memory clinic (n = 410) data sets. Results: We identified 13 different SF‐MoCAs (21 studies, n = 6477 participants) with differing test content and properties. There was a pattern of high sensitivity across the range of SF‐MoCA tests. In the published literature, for detection of post stroke cognitive impairment, median sensitivity across included studies: 0.88 (range: 0.70‐1.00); specificity: 0.70 (0.39‐0.92). In our independent validation using stroke data, median sensitivity: 0.99 (0.80‐1.00); specificity: 0.40 (0.14‐0.87). To detect dementia in older adults, median sensitivity: 0.88 (0.62‐0.98); median specificity: 0.87 (0.07‐0.98) in the literature and median sensitivity: 0.96 (range: 0.72‐1.00); median specificity: 0.36 (0.14‐0.86) in our validation. Horton's SF‐MoCA (delayed recall, serial subtraction, and orientation) had the most favorable properties in stroke (sensitivity: 0.90, specificity: 0.87, positive predictive value [PPV]: 0.55, and negative predictive value [NPV]: 0.93), whereas Cecato's “MoCA reduced” (clock draw, animal naming, delayed recall, and orientation) performed better in the memory clinic (sensitivity: 0.72, specificity: 0.86, PPV: 0.55, and NPV: 0.93). Conclusions: There are many published SF‐MoCAs. Clinicians and researchers using a SF‐MoCA should be explicit about the content. For all SF‐MoCA, sensitivity is high and similar to the full scale suggesting potential utility as an initial cognitive screening tool. However, choice of SF‐MoCA should be informed by the clinical population to be studied.

Objective This study examined cognitive function in patients with epilepsy using the AD8 screening questionnaire to assess the frequency of, and factors associated with, cognitive impairment in these patients. Method The AD8 screening questionnaire for cognitive impairment was administered to one hundred consecutive patients diagnosed with epilepsy who attended a dedicated epilepsy clinic based in a tertiary care neuroscience center. Where possible, accompanying informants also completed AD8 on behalf of the patient. Results Forty-eight percent of patients in this cohort scored above the AD8 cutoff (higher scores are considered worse) for cognitive impairment. Categorizing patient groups by AD8 score showed no difference (null hypothesis not rejected) in patient age, new or follow-up appointment, epilepsy type (partial/generalized), or treatment (monotherapy/polytherapy), but a significant difference (null hypothesis rejected) was found for disee duration, with those scoring above the AD8 cutoff having a significantly longer disease duration. There was no correlation between AD8 scores and patient age but a weak positive correlation with disease duration. AD8 questionnaires completed by informants showed a similar frequency of cognitive impairment (54%), and patient:informant AD8 scores showed substantial agreement beyond chance. Conclusions AD8 is acceptable to patients with epilepsy and their informants for the assessment of cognitive function. In this dedicated epilepsy clinic, its use suggested a high frequency of cognitive impairment in both self-rating and informant assessments. A less sensitive, more specific cognitive screening instrument (CSI) might be more desirable in this population. Duration of epilepsy or some factor related to it may contribute to cognitive symptoms.

Autoimmune encephalitis associated with antibodies (Abs) directed against the synaptic ligand-gated ion channel NMDA receptor (NMDAR) was first described as a paraneoplastic disorder in association with ovarian teratoma. Other forms of neoplasia have subsequently been reported although many patients do not have a tumour. Tumour removal, where applicable, and immunotherapy form the mainstays of treatment. We present a patient who developed NMDAR-Ab encephalitis despite being chronically immunosuppressed following organ transplantation, and who was eventually found to have an occult malignancy in the form of non-Hodgkin’s lymphoma.