Probable Dementia Of Alzheimer Type Research Articles

Individuals With Mild Cognitive Impairment and Alzheimer's Disease Benefit From Audiovisual Speech Cues and Supportive Sentence Context

Purpose Speech perception in noise becomes difficult with age but can be facilitated by audiovisual (AV) speech cues and sentence context in healthy older adults. However, individuals with Alzheimer's disease (AD) may present with deficits in AV integration, potentially limiting the extent to which they can benefit from AV cues. This study investigated the benefit of these cues in individuals with mild cognitive impairment (MCI), individuals with AD, and healthy older adult controls. Method This study compared auditory-only and AV speech perception of sentences presented in noise. These sentences had one of two levels of context: high (e.g., "Stir your coffee with a spoon") and low (e.g., "Bob didn't think about the spoon"). Fourteen older controls (M age = 72.71 years, SD = 9.39), 13 individuals with MCI (M age = 79.92 years, SD = 5.52), and nine individuals with probable Alzheimer's-type dementia (M age = 79.38 years, SD = 3.40) completed the speech perception task and were asked to repeat the terminal word of each sentence. Results All three groups benefited (i.e., identified more terminal words) from AV and sentence context. Individuals with MCI showed a smaller AV benefit compared to controls in low-context conditions, suggesting difficulties with AV integration. Individuals with AD showed a smaller benefit in high-context conditions compared to controls, indicating difficulties with AV integration and context use in AD. Conclusions Individuals with MCI and individuals with AD do benefit from AV speech and semantic context during speech perception in noise (albeit to a lower extent than healthy older adults). This suggests that engaging in face-to-face communication and providing ample context will likely foster more effective communication between patients and caregivers, professionals, and loved ones.

Rapid eye movement sleep without atonia constitutes increased risk for neurodegenerative disorders.

REM (rapid eye movement) sleep without atonia (RSWA) is a polysomnographic finding used in diagnosis of REM sleep behavior disorder (RBD). Clinical significance of idiopathic RSWA (iRSWA) unaccompanied by RBD is not known. We designed a prospective study to investigate whether iRSWA constitutes an increased risk for developing neurodegenerative disorders. Between January 2010 and December 2014, a total of 4362 patients underwent a full-night video-polysomnography. Upon detailed clinical and polysomnographical examination, patients with iRSWA and idiopathic RBD (iRBD) were enrolled into this study and followed up at every six months for at least 4years up to 9years. We had a total of 31 patients with iRBD and 67 patients with iRSWA. Mean age was higher in iRBD group than those in iRSWA group (P=.016). Restless legs syndrome/Willis-Ekbom disease was significantly more common in patients with iRBD than those in patient with iRSWA (P<.001). Eighteen patients with iRSWA (26.8%) developed iRBD after 2.6+2.2years. Six patients with iRSWA (8.9%) developed neurodegenerative disorders following 2.4+1.5years; four were diagnosed as Parkinson's disease (PD) and two developed probable Alzheimer-type dementia. In patients with iRBD, eight patients (25.8%) developed neurodegenerative disorders-all was Parkinson's disease-following 2.6+2.2years. Development of neurodegenerative diseases was positively correlated with age (P<.001) and periodic leg movements in sleep in both groups (P<.010). These results show that iRSWA may also be accepted as a risk factor in the development of PD or neurodegenerative diseases. Advanced age and periodic leg movements in sleep seem to be correlated with higher risk.

Characteristics of the dietary consumption of patients with probable dementia of Alzheimer type, at different stages: Observational study in a public outpatient clinic in são paulo, Brazil

Characteristics of the dietary consumption of patients with probable dementia of Alzheimer type, at different stages: Observational study in a public outpatient clinic in são paulo, Brazil

Evoked and event related coherence of Alzheimer patients manifest differentiation of sensory–cognitive networks

In previous studies on Alzheimer's patients it was shown that, in frontal and parietal locations, delta and theta responses of AD patients were greatly reduced. The present study analyzed coherence functions in these highly affected frontal and parietal areas. Visual sensory and event related coherences of patients with Alzheimer type dementia (AD) were analyzed comparatively. A total of 38 mild, probable AD subjects (19 untreated, 19 treated with cholinesterase inhibitors) were compared with a group of 19 healthy controls. The sensory evoked coherence and event related target coherences were analyzed for delta (1–3.5 Hz), theta (4–7 Hz), alpha (8–13 Hz), beta (15–30 Hz) and gamma (28–48 Hz) frequency ranges for long-range intra-hemispheric (F 3–P 3, F 4–P 4, F 3–T 5, F 4–T 6, F 3–O 1, F 4–O 2) electrode pairs. The healthy control group showed significantly higher values of event related coherence in “ delta”, “ theta” and “ alpha” bands in comparison to the de novo and medicated AD groups (p < 0.01 for the delta, theta and alpha) upon application of a target stimuli. In contrast, almost no changes in event related coherences were observed in beta and gamma frequency bands. Furthermore, no differences were recorded between healthy and AD groups upon application of simple light stimuli. Besides this, coherence values upon application of target stimuli were higher than sensory evoked coherence in all groups and in all frequency bands (p < 0.01). The cognitive networks of AD patients were highly impaired in comparison to networks activated by sensory stimulation, thus showing separate activation of sensory and cognitive networks.

Caring for a relative with dementia: family caregiver burden

This paper is a report of part of a study to investigate the burden experienced by families giving care to a relative with dementia, the consequences of care for the mental health of the primary caregiver and the strategies families use to cope with the care giving stressors. The cost of caring for people with dementia is enormous, both monetary and psychological. Partners, relatives and friends who take care of patients experience emotional, physical and financial stress, and care giving demands are central to decisions on patient institutionalization. A volunteer sample of 172 caregiver/care recipient dyads participated in the study in Cyprus in 2004-2005. All patients were suffering from probable Alzheimer's type dementia and were recruited from neurology clinics. Data were collected using the Memory and Behaviour Problem Checklist, Burden Interview, Center for Epidemiological Studies-Depression scale and Ways of Coping Questionnaire. The results showed that 68.02% of caregivers were highly burdened and 65% exhibited depressive symptoms. Burden was related to patient psychopathology and caregiver sex, income and level of education. There was no statistically significant difference in level of burden or depression when patients lived in the community or in institutions. High scores in the burden scale were associated with use of emotional-focused coping strategies, while less burdened relatives used more problem-solving approaches to care-giving demands. Caregivers, especially women, need individualized, specific training in how to understand and manage the behaviour of relatives with dementia and how to cope with their own feelings.

Increased frontal phase-locking of event-related theta oscillations in Alzheimer patients treated with cholinesterase inhibitors

This is a pilot study describing event-related oscillations in patients with Alzheimer-type dementia (AD). Theta responses of 22 mild probable AD subjects according to NINCDS-ADRDA criteria (11 non-treated, 11 treated by cholinesterase inhibitors), and 20 healthy elderly controls were analyzed by using the conventional visual oddball paradigm. We aimed to compare theta responses of the three groups in a range between 4–7 Hz at the frontal electrodes. At F 3 location, theta responses of healthy subjects were phase locked to stimulation and theta oscillatory responses of non-treated Alzheimer patients showed weaker phase-locking, i.e. average of Z-transformed means of correlation coefficients between single trials was closer to zero. In treated AD patients, phase-locking following target stimulation was two times higher in comparison to the responses of non-treated patients. The results indicate that the phase-locking of theta oscillations at F 3 in the treated patients is as strong as the control subjects. The F 4 theta responses were not statistically significant between the groups. Our findings imply that the theta responses at F 3 location are highly unstable in comparison to F 4 in non-treated mild AD patients and cholinergic agents may modulate event-related theta oscillatory activities in the frontal regions.

Dehydroepiandrosterone sulfate (DHEA‐S) and Alzheimer's dementia in older subjects

We investigated the association of serum dehydroepiandrosterone sulfate (DHEA-S) levels with dementia of Alzheimer's type (DAT) and impairment in selected cognitive domains (memory, language, attention and working memory) in 158 patients (75.5+/-6.7 years, 46 men) with first-diagnosed probable DAT and in 158 age- and sex-matched controls. As secondary goal, we evaluated whether DHEA-S baseline levels were associated with cumulative 6-year mortality. A negative correlation between DHEA-S levels and age was observed (R=-0.25, p<0.001). Age-stratified analysis did not show significant differences of DHEA-S levels between DAT patients and controls. No significant association was found between DHEA-S levels and impairment in selected cognitive domains. Cox regression analysis showed that baseline DHEA-S levels were not associated with cumulative 6-year mortality. In a sample of newly-diagnosed DAT patients, we did not find significant association between presence of DAT or impairment in cognitive domains and DHEA-S levels; baseline DHEA-S levels are not associated with cumulative mortality in patients and controls.

(Category-specific) semantic deficit in Alzheimer's patients: The role of semantic distance

A semantic battery comprising items from living and nonliving categories was administered to a sample of subjects suffering from probable Alzheimer's type dementia ( n = 20). The results were analyzed to test the role of semantic distance in predicting group accuracy and its possible causal link with the phenomenon of a category-specific deficit for living things in the experimental population. Our findings confirm a category effect favoring nonliving items (over and above the role of confounding variables) in patients with Alzheimer's disease and support the major role of an imbalance of semantic distance in the testing material in the genesis of this phenomenon.

A split-brain model of Alzheimer's disease?: Behavioral evidence for comparable intra and interhemispheric decline

It has been proposed that features of Alzheimer-type dementia (AD) reflect a breakdown in cortical connectivity that can be likened to a disconnection syndrome. One hypothesized consequence of this pathology is that AD patients should be disproportionally impaired on measures of interhemispheric transfer. However, there is a paucity of studies bearing on this prediction. We report the results from two measures of interhemispheric interaction obtained from healthy younger and older adults, and older adults with probable AD. One measure examined speeded simple manual responses to a lateralized light flash (i.e., the Poffenberger task) and the other examined the interhemispheric coordination of computational resources using within and across hemifield variants of visual letter-matching tasks. AD patients show an overall impairment of performance on both intra and interhemispheric conditions in all tasks. However, there is no indication of disproportionate alteration of interhemispheric processes mediating either visuomotor transfer or visual letter-matching and the allocation of computational resources. The results, therefore, call into question the appropriateness of a “split-brain” model for AD, at least in the domain of visual processing. Although the results are not specifically diagnostic of a disconnection syndrome, they are consistent with the possibility of a breakdown of cortico-cortical connectivity both within and between the hemispheres in AD.

Predicting the accuracy of a diagnosis of Alzheimer's disease with 99mTc HMPAO single photon emission computed tomography

The current clinical practice of reporting images obtained with single photon emission computed tomography (SPECT) with 99mTc- d,l-hexamethylpropylene amine oxime ( 99mTc HMPAO) images was examined by having 16 experts evaluate the appearance of SPECT images in patients with probable Alzheimer type dementia (ATD), patients with major depressive episode (DSM-IV), and healthy volunteers. The experts rated diagnostic criteria of scan appearance in respect of importance for their individual diagnostic practice. Experts were nuclear medicine specialists, psychiatrists and physicists taking part in a European multi-centre collaborative project. They examined 158 perfusion scans and then the same perfusion scans together with statistical parametric maps (SPMs). The sensitivity of experts’ diagnostic judgments was significantly and negatively correlated with the importance they attributed to reduced regional perfusion in the parietal lobes. A corresponding positive correlation was observed for diagnostic specificity against depressed and healthy volunteers. Similar results were observed with SPMs, where in addition area under the receiver operating characteristic (ROC) curve was significantly reduced with raters’ increased diagnostic reliance on frontal lobe perfusion deficits. Sensitivity was greater with SPM for patients younger than 70 years and with dementia severity. The more importance experts placed on parietal (symmetrical) perfusion deficits, the less sensitive and the more specific their diagnostic judgment was. Using multiple raters in large patient samples may provide a way of identifying successful explicit diagnostic strategies for clinical image analysis.

Medial temporal lobe atrophy predicts Alzheimer's disease in patients with minor cognitive impairment

Objectives: To investigate whether medial temporal lobe atrophy predicted outcome in patients with minor cognitive impairment and whether assessment of the medial temporal lobe could increase the predictive accuracy of...

Analysis of spontaneous, conversational speech in dementia of Alzheimer type: Evaluation of an objective technique for analysing lexical performance

Spontaneous, conversational speech in probable dementia of Alzheimer type (DAT) participants and healthy older controls was analysed using eight linguistic measures. These were evaluated for their usefulness in discriminating between healthy and demented individuals. The measures were; noun rate, pronounrate, verb rate, adjective rate, clause-like semantic unit rate (all per 100 words), including three lexical richness measures; type token ratio (TTR), Brunet's Index (W) and Honore's statistic (R). Results suggest that these measures offer a sensitive method of assessing spontaneous speech output in DAT. Comparison between DAT and healthy older participants demonstrates that these measures discriminate well between these groups. This method shows promise as a diagnostic and prognostic tool, and as a measure for use in clinical trials. Further validation in a large sample of patient versus control ‘norms’ in addition to evaluation in other types of dementia is considered.

Decreased awareness of cognitive deficits in patients with mild dementia of the Alzheimer type

To study the unawareness of cognitive deficits in patients with mild dementia of Alzheimer type (DAT). Retrospective study. We surveyed the medical records of outpatients meeting the NINCDS-ADRDA criteria for probable DAT who were able to complete the Cognitive Difficulties Scale (CDS) and had a close informant relative (IR) who could complete the family form of the same questionnaire. A department of neurology in a general teaching hospital. Eighty-eight patients, aged 73.2+/-8.6 years with a mean MMSE score of 22.5+/-3.2. Fifty-two of the 88 patients had a follow-up examination after a mean interval of 21 months. Awareness of cognitive deficits was mainly assessed as the difference between the scores on the CDS completed by the IR and the patient (Index of Unawareness, IU). Two secondary assessments of unawareness were performed: (1) an assessment by the clinician on the basis of the patient's answers to questions probing the awareness of memory deficits; (2) an evaluation by the IR of the frequency of behavioural manifestations of unawareness in everyday life. SPECT was performed in 78 patients to study the relationship between unawareness and the topography of perfusion deficits. Awareness of the cognitive deficits varied greatly between patients, according to the assessment method used and the stage of progression of the disease. Most patients with mild DAT were cognitively aware of their cognitive deficits but failed to appraise their severity and their consequences in everyday life. Decreased awareness was positively correlated with age and perfusion deficits in the frontal regions and negatively with the anxious symptomatology. However, the main correlate of unawareness was apathy. The nature of unawareness of cognitive deficits appeared to be more dimensional than categorical. In patients with mild dementia, decreased awareness appeared to be more related to affective disturbances, especially to emotional deficit or apathy, than to cognitive deficits.

Category specific semantic loss in dementia of Alzheimer's type. Functional-anatomical correlations from cross-sectional analyses.

In the context of focal brain injury, selective loss of semantic knowledge in the domain of either natural kinds or artefacts is usually considered to reflect the differential importance of temporal and frontoparietal regions to the representations of perceptual and functional attributes, respectively. It is harder to account far as a feature of a more diffuse process, and previous cross-sectional analyses of patients with dementia of Alzheimer's type (DAT) have differed over whether category effects occur. In our series of 58 patients with probable DAT, we demonstrated a significant group advantage for artefacts, and explored possible reasons for the inconsistency of this finding in other studies. A multiple single-case strategy revealed not only individuals with consistent advantages for artefacts but also individuals with consistent advantages for natural kinds. By ranking the individuals according to measures of naming performance and global intellectual ability, we showed that the strength of the group advantage for artefacts was dependent on the former but not the latter variable. The findings are discussed in the context of two competing theories of semantic breakdown in DAT. One differentiates between domains of knowledge in terms of the structure of semantic representations within a single distributed network; the other emphasizes the importance of different brain regions in the category distinction. We conclude that our findings are in keeping with the predictions of the latter hypothesis.

Nutritional patterns in elderly patients with dementia of Alzheimer type

Body weight and some nutritional serum parameters (albumin, urea nitrogen, creatinine, glycemia, hemoglobin, total cholesterol, triglycerides, potassium) were analyzed in 44 subjects aged over 60 in order to evaluate weight loss and its possible link with the progression of dementia. Patients were consecutively admitted to our Day Hospital with the complaint of psychogeriatric symptoms. They all were living at home, no one presented risk factors for malnutrition and their cognitive impairment did not exceed the 4th degree of GDS (Global Deterioration Scale). Subjects were divided into two groups on the basis of diagnosis at discharge: (i) Possible or probable dementia of Alzheimer type (30 subjects, mean age 72.1 +/- 5.9 years), (ii) Age-associated memory impairment (14 subjects, mean age 73.6 +/- 6.2 years). One year later, a second control of body weight and nutritional parameters was performed. Differences between these latter measures versus the initial values were not significant when analyzed in the total group of demented patients or in the subgroups with different degree of cognitive impairment and physical activity. A possible hypothesis to explain the absence of differences among groups is that the caregivers were very carefully looking after all the patients examined.

Brain electrical activity (quantitative EEG and bit-mapping neurocognitive CNV components), psychometrics and clinical findings in presenile subjects with initial mild cognitive decline or probable Alzheimer-type dementia.

Clinical, neuropsychological and neuropsychophysiological data (Q-EEG, ERPs and CNV/RT activity) were obtained from 24 patients who had more or less severe presenile primary cognitive decline without depression, and compared with similar data from 10 age-matched healthy volunteers (mean age, 59.4 years). All of the patients (15 M and 9 F; mean age 59.6 years) were selected according to the DSM III-R, ICD-10 and NINCDS-ADRDA criteria and underwent CT and MRI scanning, in addition to a standard clinical examination, a battery of psychometric tests, spectral EEG, and bit-mapped CNV complex and RT to S2 analyses. Twelve of the 24 patients presented an initial presenile idiopathic cognitive decline (PICD) but did not wholly fulfil the clinical and neuropsychological criteria for primary dementia or for a diagnosis of probable AD; the remaining 12 patients showed characteristic clinical signs and symptoms of a very probable early stage of presenile Alzheimer-type dementia (PAD). ANOVA, correlational and discriminant analyses of the neuropsychological test scores, and the neurophysiological and RT to S2 data revealed 22 highest-ranked between-group discriminant factors (all with a significance level of p < 0.01). The conclusive discriminant analysis retained 13 of these factors as final canonical functions, and these showed a 97% grouping accuracy (33 of the 34 subjects examined); the same percentage of correct classifications was also achieved using only the 15 best indicators in the group of CNV/RT findings. Using both of these sets of highest-ranked discriminators, all of the normal subjects and all of the PAD patients were correctly classified; only 1 PICD patient was misclassified as normal when the first group of 13 factors was used, and another PICD patient was misclassified as PAD using the second group of 15 factors. Our findings suggest that, providing they are correctly performed and interpreted, these non-invasive techniques may be an important tool for identifying incipient stages of presenile Alzheimer-type dementia.

Comparison of executive and visuospatial memory function in Huntington's disease and dementia of Alzheimer type matched for degree of dementia.

Groups of patients with Hungington's disease and probable dementia of Alzheimer type (DAT) matched for level of dementia on the basis of mini mental state examination scores were compared in several tests of visual memory and tests sensitive to frontal lobe dysfunction. Whereas recall of patients with DAT tended to be worse on the Kendrick object learning test, the two groups were equivalent on tests of sensorimotor ability and delayed matching to sample performance. By contrast, the patients with Huntington's disease were significantly worse on tests of pattern and spatial recognition, simultaneous matching to sample, visuospatial paired associates, and on three tests sensitive to frontal lobe dysfunction--namely, the Tower of London test of planning, spatial working memory, and a visual discrimination learning and reversal paradigm. The impairments in these tests, however, did not always qualitatively resemble those seen in patients with frontal lobe damage and may be more characteristic of primary neostriatal deficit. In the visual discrimination paradigm the patients with Hungtington's disease were significantly worse than the patients with DAT at the simple reversal stage, where they displayed significant preservation to the previously rewarded alternative. The results are consistent with the hypothesis that patients with Huntington's disease exhibit deficits in tests sensitive to frontostriatal dysfunction and that this form of intellectual deterioration is qualitatively distinct from that seen in Alzheimer's disease.

The Influence of a Highly Participatory Peer on Motivating Group Behaviors of Lower Functioning Persons who have Probable Alzheimer's Type Dementia: A Feasibility Study

This clinical study was concerned with determining the feasibility of increasing participatory behavior in a small group ( n = 8) of residential care residents with probable Alzheimer's disease and related dementias, particularly when a highly participatory peer was part of the group. A variety of music therapy interventions designed to stimulate [participation] were provided to the residents. Over a period of 42 sessions, group participation fluxuated from 55% to 69%. Results indicated that adding a more highly participatory peer to a small group of lower functioning persons with dementias could positively influence the level of participation within the group.

Cognitive declines correlate with decreased cortical volume and perfusion in dementia of Alzheimer type

Cerebral CT changes are correlated with cognitive declines among 18 patients with probable dementia of Alzheimer type (DAT) (7 men, 11 women, mean age 75.4 years) and are compared for control purposes with similar measures among 18 age-matched normal volunteers (8 men, 10 women, mean age 73.7 years). Mean follow-up intervals are 28.6 months for DAT and 27.0 months for controls. For DAT, annual rates for ventricular volume enlargement are + 9.2% and for cortical atrophy are −2.1%. Annual reductions in regional cerebral perfusions per 100 g brain/min, are: total cortex −1.1 ml, frontal −1.2 ml, temporal and parietal −0.9 ml, basal ganglia −1.6 ml, thalamus −2.5 ml, total white matter −0.6 ml, frontal white matter −0.7 ml. At entry evaluation, compared to normals, DAT patients had reduced CT densities in white matter, but not in cortex. Nevertheless, cortical CT densities declined progressively at annual rates of −0.72 Hounsfield units (HU), but remained constant in white matter. Annual point score declines for Cognitive Capacity Screening Examinations were −2.0 and for Mini Mental State: −2.8. Controls showed no cognitive change. Multiple regression analyses correlate cognitive declines with: (1) reductions in perfusion within parietal cortex ( p = 0.015), (2) decreases in cortical volume ( p = 0.019), and (3) decreases in HU within subcortical gray matter ( p = 0.007).

Quantitative EEG mapping and PET in Alzheimer's disease

Quantitative analysis of topographical EEG was studied in comparison with measurement of regional glucose metabolism by PET in 42 patients with clinical diagnosis of probable dementia of Alzheimer type (AD) and in 15 age-matched normal controls. Measures analyzed included global and regional data from areas typically affected and not affected by AD pathology. While disturbance of metabolism followed a typical regional pattern, relative alpha, theta and delta power were more globally altered without selectivity for specific regions. Separation between AD and age matched controls by relative theta power was correct in 86% and was close to that by temporo-parietal glucose metabolism (correct classification 87%). Relative theta power as well as temporo-parietal glucose metabolism were significantly correlated ( τ B = 0.54 and −0.53, respectively) to severity of AD assessed by the global deterioration scale. These results indicate that EEG measures may be used with an accuracy close to metabolic values from PET for the assessment of severity of AD.