Addenbrooke's Cognitive Examination Scores Research Articles

Improving Mood and Cognitive Symptoms in Huntington's Disease With Cariprazine Treatment.

In Huntington's disease (HD), the main clinical symptoms include depression, apathy, cognitive deficits, motor deficiencies and involuntary movements. Cognitive, mood and behavioral changes may precede motor symptoms by up to 15 years. The treatment of these diverse symptoms is challenging. Tetrabenazine and deutetrabenazine are the only medications specifically approved for Huntington's chorea, but they do not affect the non-motor symptoms. For these, antidepressants, antipsychotics, and benzodiazepines have demonstrated benefit in some cases and can be used off-label. These drugs, due to sedative side effects, may negatively influence cognition. Sixteen patients having HD received a 12-week off-label cariprazine (CAR) treatment (1.5–3 mg/day). Cognitive performance and behavioral changes were measured by the Addenbrooke Cognitive Examination (ACE) test, the Cognitive and Behavioral part of the Unified Huntington's Disease Rating Scale (UHDRS), and the Beck Depression Inventory (BDI). Mixed model for repeated measures was fitted to the data, with terms of visit, baseline (BL) and their interaction. Cariprazine treatment resulted in the following changes from BL to week 12, respectively: the mean score of BDI decreased from 17.7 ± 10.7 to 10.0 ± 10.7 (p <0.0097), while the Behavioral Assessment score of the UHDRS decreased from 54.9 ± 11.3 to 32.5 ± 15.4 (p < 0.0001); ACE score increased from 75.1 ± 11.0 to 89.0 ± 9.3 (p < 0.0001); Cognitive Verbal Fluency score from 6.2 ± 2.5 to 7.7 ± 2.7 (p < 0.0103); Symbol Digit Test from 9.2 ± 6.9 to 12.3 ± 8.9 (p < 0.0009). Mild akathisia was the most frequent side effect, presenting in 2 out of 16 patients (12.5%). We conclude that CAR had a positive effect on depressive mood, apathy and cognitive functions in patients with early stage of HD. Based on the neurobiological basis of these symptoms, CAR can improve the dopamine imbalance of the prefrontal cortex. This draws attention to the transdiagnostic approach which supports the further understanding of the similar symptomatology of different neuropsychiatric disorders and helps to identify new indications of pharmaceutical compounds.

Respiratory function and cognitive profile in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is increasingly recognized as a multisystem disorder with 30%-50% of patients exhibiting cognitive impairment. The pathophysiological mechanisms of cognitive dysfunction are probably multifactorial although hypoventilation secondary to respiratory dysfunction may contribute to cognitive decline. The current study aimed to identify the relationship between respiratory function in ALS patients and the presence and degree of cognitive impairment. Amyotrophic lateral sclerosis patients were prospectively recruited from a multidisciplinary ALS clinic. Baseline clinical assessments including respiratory function as assessed by spirometry were recorded with forced vital capacity (FVC) ≤ 75% considered to be reduced respiratory function. Cognitive testing was performed utilizing the Addenbrooke's Cognitive Examination (ACE) and the Mini-Mental State Examination (MMSE). From a cohort of 100 ALS patients, 48% were categorized as having impaired respiratory function (FVC=58.24%±2.15%) whilst 52% had normal function (88.65%±1.27%). Compared to the group with normal respiratory function (ACE 90.68 ± 0.89, MMSE 28.22 ± 0.21), patients with respiratory dysfunction had significantly reduced cognitive function (ACE 86.83± 1.5, P=0.025; MMSE 26.29± 0.45, P=0.029). Furthermore, subscores demonstrated significant differences between the groups with respect to domains in memory (P=0.003) and attention (P=0.05) with a trend observed in fluency (P=0.082). There was a significant correlation between patient baseline FVC and ACE scores as well as between FVC and memory and fluency subscores (P<0.01). Amyotrophic lateral sclerosis patients with respiratory compromise were more likely to develop reduced cognitive function. In addition to improving physical function, it remains plausible that non-invasive ventilation may alter the progression of cognitive impairment in ALS patients and potentially improve overall quality of life and carer burden.

Altered Low-Frequency EEG Connectivity in Mild Cognitive Impairment as a Sign of Clinical Progression.

Mild cognitive impairment (MCI) is associated with clinical progression to Alzheimer's disease (AD) but not all patients with MCI convert to AD. However, it is important to have methods that can differentiate between patients with MCI who progress (pMCI) and those who remain stable (sMCI), i.e., for timely administration of disease-modifying drugs. In the current study, we wanted to investigate whether quantitative EEG coherence and imaginary part of coherency (iCoh) could be used to differentiate between pMCI and sMCI. 17 patients with AD, 27 patients with MCI, and 38 older healthy controls were recruited and followed for three years and 2nd year was used to determine progression. EEGs were recorded at baseline and coherence and iCoh were calculated after thorough preprocessing. Between pMCI and sMCI, the largest difference in total coherence was found in the theta and delta bands. Here, the significant differences for coherence and iCoh were found in the lower frequency bands involving the temporal-frontal connections for coherence and parietal-frontal connections for iCoh. Furthermore, we found a significant negative correlation between theta coherence and the Addenbrooke's Cognitive Examination (ACE) (p = 0.0378; rho = -0.2388). These findings suggest that low frequency coherence and iCoh can be used to determine, which patients with MCI will progress to AD and is associated with the ACE score. Low-frequency coherence has previously been associated with increased hippocampal atrophy and degeneration of the cholinergic system and may be an early marker of AD pathology.

Primary lateral sclerosis and the amyotrophic lateral sclerosis-frontotemporal dementia spectrum.

To investigate whether primary lateral sclerosis (PLS) represents part of the amyotrophic lateral sclerosis-frontotemporal dementia (ALS-FTD) spectrum of diseases. Comprehensive assessment was taken on 21 patients with PLS and results were compared to patients diagnosed with pure motor ALS (n = 27) and ALS-FTD (n = 12). Clinical features, Addenbrooke's Cognitive Examination (ACE) scores, Motor Neuron Disease Behaviour (Mind-B) scores, motor disability on the ALS functional rating scale (ALSFRS) and survival times were documented. Motor cortex excitability was evaluated using transcranial magnetic stimulation (TMS). Global cognition was impaired in PLS (mean total ACE score 82.5 ± 13.6), similar to ALS-FTD (mean total ACE score 76.3 ± 7.7, p > 0.05) while behavioural impairments were not prominent. TMS revealed that resting motor threshold (RMT) was significantly higher in PLS (75.5 ± 6.2) compared ALS-FTD (50.1 ± 7.2, p < 0.001) and ALS (62.3 ± 12.6, p = 0.046). Average short-interval intracortical inhibition (SICI) was similar in all three patient groups. The mean survival time was longest in PLS (217.4 ± 22.4months) and shortest in ALS-FTD (38.5 ± 4.5months, p = 0.002). Bulbar onset disease (β = - 0.45, p = 0.007) and RMT (β = 0.54, p = 0.001) were independent predictors of global cognition while motor scores (β = 0.47, p = 0.036) and SICI (β = 0.58, p = 0.006) were significantly associated with ALSFRS. The cognitive profile in PLS resembles ALS-FTD, without prominent behavioural disturbances. A higher RMT in PLS than ALS and ALS-FTD is consistent with differential cortical motor neuronal abnormalities and more severe involvement of corticospinal axons while SICI, indicative of inhibitory interneuronal dysfunction was comparable with ALS and ALS-FTD. Overall, while these findings support the notion that PLS lies on the ALS-FTD spectrum, the mechanisms underlying slow disease progression are likely to be distinct in PLS.

Cognition in advanced normal pressure hydrocephalus: A pilot study from South India.

Literature on cognition in normal pressure hydrocephalus (NPH) is sparse and more so on cognition in advanced NPH. To study the cognitive profile in a hospital-based cohort of cognitively-advanced NPH. This was a prospective cross-sectional study. The patients included those availing dementia care service from three different tertiary care centres during a period of 5 years from 2010 to 2014. Patients were considered to have cognitively-advanced NPH if the Addenbrooke's Cognitive Examination(ACE) score was 50 or less. In addition to ACE, the patients underwent a battery of other neuropsychologic tests including the digit forward test, Trail A and Trail B, Rey auditory verbal learning test, Cambridge behaviour inventory, hospital anxiety and depression scale, informant questionnaire for cognitive decline in the elderly, and scale for activities of daily living. Data analysis was done using the Statistical Package for the Social Sciences. Dementia was confirmed in 326 cases, 193 (59.2%) with NPH, 77 (23.6%) with Alzheimer's disease (AD), 29 (8.9%) with frontotemporal dementia (FTD), and 27 (8.3%) with vascular dementia based on the commonly used criteria. Detailed neuropsychologic assessment could be done in 23 patients with NPH and 15 patients with AD. The mean age was 72.06 ± 9.62 years. Thirteen (56.5%) of the patients were males, and the mean duration of education was for 7.74 ± 3.21 years; the mean duration of illness was for 2.73 ± 2.72 years. The mean mini-mental state examination score was 11.6 ± 5.2 and the mean ACE score was 27.26 ± 1.3. The most severely impaired factor was memory (mean score 6.7 ± 4; percentage of maximum score [PMS] 19.41 ± 11.58) and the least affected was language (mean score 15.56 ± 8.25; PMS 37.06 ± 19.63. No significant difference was seen between ACE total score or subscores when the 15 advanced AD patients were compared. The cognitive profile of NPH at an advanced stage was similar to that seen in advanced AD. As advanced NPH shows cognition similar to cortical dementia, the pathologic correlate in NPH may not be hydrocephalus alone.

Early detection of Alzheimer's disease using MRI hippocampal texture.

Cognitive impairment in patients with Alzheimer's disease (AD) is associated with reduction in hippocampal volume in magnetic resonance imaging (MRI). However, it is unknown whether hippocampal texture changes in persons with mild cognitive impairment (MCI) that does not have a change in hippocampal volume. We tested the hypothesis that hippocampal texture has association to early cognitive loss beyond that of volumetric changes. The texture marker was trained and evaluated using T1-weighted MRI scans from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database, and subsequently applied to score independent data sets from the Australian Imaging, Biomarker & Lifestyle Flagship Study of Ageing (AIBL) and the Metropolit 1953 Danish Male Birth Cohort (Metropolit). Hippocampal texture was superior to volume reduction as predictor of MCI-to-AD conversion in ADNI (area under the receiver operating characteristic curve [AUC] 0.74 vs. 0.67; DeLong test, p = 0.005), and provided even better prognostic results in AIBL (AUC 0.83). Hippocampal texture, but not volume, correlated with Addenbrooke's cognitive examination score (Pearson correlation, r = -0.25, p < 0.001) in the Metropolit cohort. The hippocampal texture marker correlated with hippocampal glucose metabolism as indicated by fluorodeoxyglucose-positron emission tomography (Pearson correlation, r = -0.57, p < 0.001). Texture statistics remained significant after adjustment for volume in all cases, and the combination of texture and volume did not improve diagnostic or prognostic AUCs significantly. Our study highlights the presence of hippocampal texture abnormalities in MCI, and the possibility that texture may serve as a prognostic neuroimaging biomarker of early cognitive impairment.

Study of cognitive profile in the elderly presenting with both depressive and cognitive symptoms

Background: Elderly patients presenting with cognitive and depressive symptoms often create a diagnostic challenge between depression and the dementing process. Various screening and diagnostic instruments have been developed for differentiating the two, one of which is Addenbrooke's cognitive examination (ACE). However, results have not been consistent across various studies, and not much data is available in the Indian context. Aims and Objectives: To study cognition in elderly patients presenting with both cognitive and depressive symptoms at the baseline and at 3 months follow-up after starting antidepressants, and to compare the two profiles. Materials and Methods: It was a follow-up study with 70 participants who had presented with both depressive and cognitive symptoms. Tablet escitalopram was given and ACE was performed at the baseline and at 3 months after starting antidepressants. Improvement on ACE was present in 37 participants and absent in 33 participants. The cognitive profile of these two groups was subjected to statistical analysis. Wilcoxon signed-rank test was used to study the difference between the full and domain ACE scores between the preintervention phase and postintervention phase within each group. Results: There is a significant difference between preintervention and postintervention full ACE scores and different domain scores in the depression group unlike in the MCI group. Conclusion: Diagnostic tools such as ACE can be utilized for differentiating mood disorder with an actual dementing process. It also reveals the need for periodic assessments of such patients.

Subjective depressive mood and regional cerebral blood flow in mild Alzheimer's disease

Depressive symptoms are common in patients with Alzheimer's disease (AD) and increase the caregiver burden, although the etiology and pathologic mechanism of depressive symptoms in AD patients remain unclear. In this study, we tried to clarify the cerebral blood flow (CBF) correlates of subjective depressive symptoms in AD. Seventy-six consecutive patients with AD were recruited from outpatient units of the Memory Clinic of Okayama University Hospital. Subjective depressive symptoms were evaluated using the short version of the Geriatric Depression Scale (GDS). All patients underwent brain SPECT with 99mTc-ethylcysteinate dimer, and the SPECT images were analyzed by the Statistical Parametric Mapping 8 program. No significant differences between groups with high and low GDS scores were found with respect to age, sex, years of education, and revised Addenbrooke's Cognitive Examination scores. Compared to patients with low scores on GDS, patients with high scores showed significant hypoperfusion in the left inferior frontal region. The left inferior frontal region may be significantly involved in the pathogenesis of subjective depressive symptoms in AD. Subjective and objective depressive symptoms may have somewhat different neural substrates in AD.

UNNOTICED IN CHILDHOOD, DISABLING IN ADULTHOOD: A PROGRESSIVE BUT TREATABLE DISEASE…

A 64 year old Caucasian man presented with subtle cognitive decline of uncertain duration and a six month history of progressive difficulty mobilising with falls. He reported increasing stiffness in...

ANTI GLUTAMIC ACID DECARBOXYLASE ANTIBODY MEDIATED ENCEPHALOPATHY WHILE ON ETANERCEPT IN A PATIENT WITH MULTIPLE AUTOIMMUNE DISEASES

A 39 year old lady presented with an altered mental state and unsteadiness of gait. She had a history of juvenile idiopathic arthritis, autoimmune thyroiditis and alopecia, protein S deficiency...

Trail Making Test B and brain perfusion imaging in mild cognitive impairment and mild Alzheimer's disease

The Trail Making Test (TMT) has long been used to investigate deficits in cognitive processing speed and executive function in humans. However, there are few studies that elucidate the neural substrates of the TMT. The aim of the present study was to identify the brain regional perfusion patterns associated with performance on TMT part B (TMT-B) in patients with amnestic mild cognitive impairment (aMCI) or mild Alzheimer's disease (AD). Twenty-one patients with good TMT-B scores and 21 age- and sex-matched patients with poor TMT-B scores were selected. All 42 subjects underwent brain single photon emission computed tomography (SPECT), and the SPECT images were analyzed by statistical parametric mapping. No significant differences between good- and poor-scoring groups were found with respect to years of education, Addenbrooke's Cognitive Examination scores, and scores on TMT-A. Compared to patients with good scores on TMT-B, patients with poor scores showed significant hypoperfusion in the bilateral anterior cingulate extending to the posterior region on the right side, bilateral caudate nucleus and putamen, and bilateral thalamus. Analysis of 63 AD or aMCI subjects revealed significant correlation a between regional cerebral blood flow in the right cingulate cortex and TMT-B scores. Our results suggest that functional activity of the anterior cingulate, striatum and thalamus is closely related to performance time on TMT-B. The performance time on the TMT-B score might be a promising index of dysfunction of the anterior cingulate, striatum, and thalamus among patients with aMCI or mild AD.

Trail Making Test Part A and Brain Perfusion Imaging in Mild Alzheimer's Disease

Background/Aims: The Trail Making Test (TMT) has long been used to investigate deficits in cognitive processing speed and executive function in humans. However, there are few studies that elucidate the neural substrates of the TMT. The aim of the present study was to identify the regional perfusion patterns of the brain associated with performance on the TMT part A (TMT-A) in patients with Alzheimer's disease (AD). Methods: Eighteen AD patients with poor performance on the TMT-A and 36 age- and sex-matched AD patients with good performance were selected. All subjects underwent brain single photon emission computed tomography. Results: No significant differences between the good and poor performance groups were found with respect to years of education and revised Addenbrooke's Cognitive Examination scores. However, higher z-scores for hypoperfusion in the bilateral superior parietal lobule were observed in the group that scored poorly on the TMT-A compared with the good performance group. Conclusion: Our results suggest that functional activity of the bilateral superior parietal lobules is closely related to performance time on the TMT-A. Thus, the performance time on the TMT-A might be a promising index of dysfunction of the superior parietal area among mild AD patients.

Frontal assessment battery and brain perfusion imaging in Alzheimer's disease

The frontal assessment battery (FAB) is reported to be a useful tool for assessing frontal dysfunction. However, the neural substrates involved in patients with Alzheimer's disease (AD) remain to be elucidated. The aim of the present study was to identify the regional perfusion patterns of the brain associated with performance scores on the FAB of patients with AD using brain perfusion assessed by single photon emission computed tomography (SPECT). Twenty-four AD patients with high scores and 24 age- and sex-matched AD patients with low scores on the FAB were selected from 470 consecutive Japanese patients of the Memory Clinic of Okayama University Hospital. All 48 participants underwent brain SPECT with 99mTc-ethylcysteinate dimer, and the SPECT images were analyzed by statistical parametric mapping. No significant differences were found between high and low FAB scoring groups with respect to Addenbrooke's Cognitive Examination scores, Mini-Mental State Examination scores, or the depression score of the Neuropsychiatric Inventory subscale. Compared with patients with high scores on the FAB, AD patients with low scores showed significant hypoperfusion in the left middle frontal gyrus (MFG) and the right superior frontal gyrus (SFG) extending to the left SFG. Our results suggest that functional activity of the SFG and MFG is closely related to the FAB score. The FAB might be a promising strategy to detect early stages of AD with low SFG and MFG function.

Perseverative errors on the Wisconsin Card Sorting Test and brain perfusion imaging in mild Alzheimer's disease

The Wisconsin Card Sorting Test (WCST) has long been used to investigate deficits in executive function in humans. The majority of studies investigating deficient WCST performance focused on the number of categories achieved (CA) and the number of perseverative errors of the Nelson type (PEN). However, there is insufficient evidence that these two measures reflect the same neural deficits. Twenty AD patients with high PEN scores, and 20 age- and sex-matched AD patients with low PEN scores were selected. All 40 subjects underwent brain SPECT, and the SPECT images were analyzed by Statistical Parametric Mapping. No significant differences were found between high and low PEN score groups with respect to years of education, Addenbrooke's Cognitive Examination scores, and Mini-Mental State Examination scores. However, higher z scores for hypoperfusion in the bilateral rectal and orbital gyri were observed in the high PEN score group compared with the low PEN score group. Our results suggest that functional activity of the bilateral rectal and orbital gyri is closely related to PEN scores on a modified WCST (mWCST). The PEN score on a mWCST might be a promising index of dysfunction of the orbitofrontal area among patients with mild AD.

Kana Pick-out Test and brain perfusion imaging in Alzheimer's disease

The Kana Pick-out Test (KPT), which was developed in Japan, is suitable for evaluating frontal lobe function and screening for mild dementia. However, the neural substrates involved remain to be elucidated. The aim of the present study was to identify the regional perfusion patterns in the brain associated with performance scores on the KPT in patients with mild Alzheimer's disease (AD), using brain perfusion assessed by single photon emission computed tomography (SPECT). Twenty AD patients with high scores on the KPT and 20 age- and sex-matched AD patients with low scores were selected from 227 consecutive Japanese patients of the Memory Clinic of Okayama University Hospital. All 40 subjects underwent brain SPECT with 99mTc-ethylcysteinate dimer, and the SPECT images were analyzed by Statistical Parametric Mapping. With the exception of KPT scores, no significant differences were found between high and low scoring groups with respect to Addenbrooke's Cognitive Examination scores, Mini-mental State Examination scores, or the depression score of the Neuropsychiatric Inventory subscale. Compared to patients with high scores on the KPT, AD patients with low scores on the KPT showed significant hypoperfusion in the left subgenual cingulate gyrus (SGC) extending to the right SGC. Our results suggest that functional activity of the SGC is closely related to scores on the KPT. KPT might be a promising strategy to use in detecting early stages of AD with low SGC function.

Validation of Addenbrooke's cognitive examination for detecting early dementia in a Japanese population

There is a clear need for brief, but sensitive and specific, cognitive screening instruments for dementia. We assessed the diagnostic accuracy of the Japanese version of Addenbrooke's Cognitive Examination (ACE) in identifying early dementia in comparison with the conventional Mini-Mental State Examination (MMSE). Standard tests for evaluating dementia screening tests were applied. A total of 201 subjects (Alzheimer's disease (AD) = 65, frontotemporal dementia (FTD) = 24, vascular dementia = 26, dementia with Lewy bodies = 11, mild cognitive impairment (MCI) = 13, and controls = 62) participated in this study. The reliability of the ACE was very good (alpha coefficient = 0.82). In our patient series, the sensitivity for diagnosing dementia with an ACE score of ≤ 74 was 0.889 with a specificity of 0.987, and the sensitivity of an ACE score of ≤ 80 was 0.984 with a specificity of 0.867. The Japanese version of the ACE is a very accurate instrument for the detection of early dementia, and should be widely used in clinical practice.

Measurement of physical performance and objective fatigability in people with mild-to-moderate traumatic brain injury

The aims of this study were to objectively measure the physical performance and physical endurance of patients with traumatic brain injury with minimization of cognitive and psychological fatigue, and to compare the physical performance of brain injured patients with that of healthy controls. This was a nonrandomized partially blinded controlled study. The study setting was the Outpatient Multidisciplinary Brain Injury Clinic in the Department of Physical Medicine and Rehabilitation of a tertiary care university teaching hospital. Participants included an experimental group that comprised independently ambulant men (age 18-55 years) with mild-to-moderate traumatic brain injury (n = 24) who complained of greater fatigue than before their injury and an age-matched and sex-matched control group (n = 24). The intervention included the Six-Minute Walk Test. The primary outcome measures were the Six-Minute Walk Distance, the Fatigue Severity Scale, Addenbrooke's Cognitive Examination, and the Fatigue Visual Numeric Scale; the secondary outcome measures were the Physiological Cost Index of Walking and the Borg Scale of Perceived Exertion. The Six-Minute Walk Distance of the experimental group (452.33+/-68.816) when compared with that of the control group (518.08+/-92.114) was reduced by 12.7 and 30.5%, respectively, when compared with the predicted Six-Minute Walking Distance (650.04+/-79.142) for the same age and sex. The mean Fatigue Severity Scale values were 2.51 and 1.62 for the experimental and control groups, respectively. The mean Addenbrooke's Cognitive Examination Score for the patients was 85.5+/-7.265. In conclusion, the Six-Minute Walk Test is useful in segregating physical fatigue from cognitive and psychological aspects of fatigue when cognitive and psychological dimensions are known. The Six-Minute Walk Test can be used as a tool for exercise intensity prescription in men with mild-to-moderate brain injury, to avoid the deleterious effects of fatigue.

A neuropsychological battery to detect specific executive and social cognitive impairments in early frontotemporal dementia

Traditional cognitive tests may not be sensitive for the early detection of executive and social cognitive impairments in the behavioural variant of frontotemporal dementia. The aim of this study was to detect specific executive and social cognitive deficits in patients with early behavioural variant frontotemporal dementia using a battery of tests previously shown to be sensitive to frontal lobe dysfunction. Behavioural variant frontotemporal dementia patients and paired controls were assessed with a complete standard neuropsychological battery evaluating attention, memory, visuospatial abilities, language and executive functions. All participants were then assessed with our Executive and Social Cognition Battery, which included Theory of Mind tests (Mind in the Eyes, Faux Pas), the Hotel Task, Multiple Errands Task-hospital version and the Iowa Gambling Task for complex decision-making. Patients were divided into two groups according to their Addenbrooke's Cognitive Examination scores, a measure of general cognitive status. Low Addenbrooke's Cognitive Examination patients differed from controls on most tasks of the standard battery and the Executive and Social Cognition Battery. While high Addenbrooke's Cognitive Examination patients did not differ from controls on most traditional neuropsychological tests, significant differences were found between this high-functioning behavioural variant of frontotemporal dementia group and controls on most measures of our Executive and Social Cognition Battery. Our results suggest that the Executive and Social Cognition Battery used in this study is more sensitive in detecting executive and social cognitive impairment deficits in early behavioural variant of frontotemporal dementia than the classical cognitive measures.

Differentiation of semantic dementia and Alzheimer's disease using the Addenbrooke's Cognitive Examination (ACE)

The Addenbrooke's Cognitive Examination (ACE) is a simple diagnostic tool bridging the gap between the very brief Mini Mental State Exam (MMSE) and much longer test batteries used by neuropsychologists which has proven extremely popular internationally. We aimed to assess the ability of the ACE to differentiate semantic dementia (SD) from Alzheimer's disease (AD). The ACE was administered to three groups: SD patients (n = 40) and two separate groups of AD patients (n = 40 in each), matched for overall ACE or MMSE score. Significant differences were found between SD and both AD groups for the ACE sub-scores of naming, reading and orientation in time. Discriminant analysis (SD versus AD) led to the formulation of a 'semantic index' (naming plus reading minus scores for serial-7s, orientation in time and drawing). Application of the semantic index to the patient data found values of less than zero to be predictive of SD rather than AD with 88% sensitivity and 90% specificity. Validation analysis in an independent sample of 24 SD and AD patients proved even more favourable. The overall ACE score is known to be a sensitive, and specific, indicator of early neurodegenerative dementia; this study shows that the ACE can also be used to detect SD through application of the semantic index.

Addenbrooke's Cognitive Examination (ACE) for the diagnosis and differential diagnosis of dementia

Objectives The Addenbrooke's Cognitive Examination (ACE) is reported to be a highly sensitive and specific “bedside” test for the diagnosis of dementia, but large pragmatic studies of its use in day-to-day clinical practice are lacking. This study measured diagnostic accuracy of ACE in a large cohort of consecutive patients referred to a dedicated Cognitive Function Clinic. Patients and methods Consecutive new referrals over a 3.5-year period were administered the ACE ( n = 285). ACE scores and subscores (VLOM ratio) were compared to clinical diagnoses of dementia and dementia subtype, established on the basis of widely accepted diagnostic criteria and at least 12-month follow-up. Results ACE had good sensitivity, specificity, and positive predictive value for the diagnosis of dementia, with excellent diagnostic accuracy as measured by area under the receiver operating characteristic curve. However, a lower cutoff than that used in the index paper was required for optimum test sensitivity and specificity. ACE VLOM ratio subscore for the differential diagnosis of Alzheimer's disease and frontotemporal dementia proved less accurate. Conclusion This study suggests that ACE is useful for the diagnosis of dementia in routine clinical practice but that other instruments may be required for the differential diagnosis of the dementia syndrome.