Detection of Alzheimer's disease and dementia in the preclinical phase: population based cohort study

ObjectivesTo evaluate a simple three step procedure to identify people in the general population who are in the preclinical phase of Alzheimer''s disease and dementia.DesignThree year population based cohort study.SettingKungsholmen cohort, Stockholm, Sweden.Participants1435 people aged 75-95 years without dementia.AssessmentsSingle question asking about memory complaints, assessment by mini-mental state examination, and neuropsychological testing.ResultsNone of the three instruments was sufficiently predictive of Alzheimer''s disease and dementia when administered separately. After participants had been screened for memory complaints and global cognitive impairment, specific tests of word recall and verbal fluency had positive predictive values for dementia of 85-100% (95% confidence intervals range from 62% to 100%). However, only 18% of future dementia cases were identified in the preclinical phase by this three step procedure. Memory complaints were the most sensitive indicator of Alzheimer''s disease and dementia in the whole population, but only half the future dementia cases reported memory problems three years before diagnosis.ConclusionThis three step procedure, which simulates what might occur in clinical practice, has a high positive predictive value for dementia, although only a small number of future cases can be identified.

What is already known on this topic

Alzheimer''s disease is characterised by a preclinical phase, during which cognitive deficits are seen before diagnosisElderly people with subjective memory complaints and objective global cognitive impairment have a high risk of developing Alzheimer''s disease and dementia

What this study adds

This three step procedure (self report of memory complaints, test of global cognitive functioning, and then domain specific cognitive tests) has a positive predictivity of 85-100% for Alzheimer''s disease and dementia at three yearsHowever, only 18% of people in the preclinical phase can be identified using this procedureAbout half of the people in the preclinical phase of Alzheimer''s disease and dementia do not report problems with their memory three years before diagnosis     

The Clinical Utility of Informants' Appraisals on Prospective and Retrospective Memory in Patients with Early Alzheimer's Disease

Increasing studies suggest the importance of including prospective memory measures in clinical evaluation of dementia due to its sensitivity and functional relevance. The Prospective and Retrospective Memory Questionnaire (PRQM) is originally a self-rated memory inventory that offers a direct comparison between prospective and episodic memory. However, the informant''s report has been recognized as a more valid source of cognitive complaints. We thus aimed to examine the validity of the informant-rated form of the PRMQ in assessing memory function of the patients and in detecting individuals with early dementia. The informants of 140 neurological outpatients with memory complaints completed the Taiwan version of the PRMQ. Tests of prospective memory, short-term memory, and general cognitive ability were also administered to non-demented participants and patients with early stages of Alzheimer''s disease (AD). Results showed significant relationships between the PRMQ ratings and objective cognitive measures, and showed that higher ratings on the PRMQ were associated with increasing odds of greater dementia severity. Receiver operative characteristic (ROC) curves showed an adequate ability of the PRMQ to identify patients with dementia (93% sensitivity and 84% specificity). Hierarchical regression revealed that the PRMQ has additional explanatory power for dementia status after controlling for age, education and objective memory test results, and that the prospective memory subscale owns predictive value for dementia beyond the retrospective memory subscale. The present study demonstrated the external validity and diagnostic value of informants'' evaluation of their respective patients'' prospective and retrospective memory functioning, and highlighted the important role of prospective memory in early dementia detection. The proxy-version of the PRMQ is a useful tool that captures prospective and episodic memory problems in patients with early AD, in combination with standardized cognitive testing.     

Episodic memory: insights from semantic dementia

Semantic dementia, also known as the temporal lobe variant of fronto-temporal dementia, results in a progressive yet relatively pure loss of semantic knowledge about words, objects and people, and is associated with asymmetric, focal atrophy of the antero-lateral temporal lobes. Semantic dementia provides a unique opportunity to study the organization of long-term memory particularly since initial observations suggested sparing of episodic memory. Recent studies reveal, however, a more complex but theoretically revealing pattern. On tests of autobiographical memory, patients with semantic dementia show a 'reverse step function' with sparing of recall of events from the most recent 2 to 5 years but impairment on more distant life periods. Anterograde recognition memory for visual materials is extremely well preserved, except in the most deteriorated cases, although performance is heavily reliant upon perceptual information about the studied stimuli, particularly for items that are no longer known by the subjects. On tests of verbal anterograde memory such as word learning, performance is typically poor even for words which are 'known' to the patients. A source discrimination experiment, designed to evaluate familiarity and recollection-based anterograde memory processes, found that patients with semantic dementia showed good item detection, although recollection of source was sometimes impaired. Semantic knowledge about studied items and measures of item detection and source discrimination were largely independent. The implications of these findings for models of long-term memory are discussed. The results support the concept that episodic memory, or at least the recall of temporally specific autobiographical experiences, draws upon a number of separable memory processes, some of which can function independently of semantic knowledge.     

Black African and Caribbean British Communities’ Perceptions of Memory Problems: “We Don’t Do Dementia.”

ObjectivesWe aimed to identify and explore the barriers to help-seeking for memory problems, specifically within UK Black African and Caribbean communities.MethodWe purposively recruited participants from community groups and subsequent snowball sampling, to achieve a maximum variation sample and employed thematic analysis. Our qualitative semi-structured interviews used a vignette portraying a person with symptoms of dementia, and we asked what they or their family should do. We stopped recruiting when no new themes were arising.

Results and significance

We recruited 50 people from a range of age groups, country of origin, time in the UK, religion and socio-economic background. Some of the barriers to presentation with dementia have been reported before, but others were specific to this group and newly identified. Many people recognised forgetfulness but neither that it could be indicative of dementia, nor the concept of dementia as applying to them. Dementia was viewed as a white person’s illness. Participants felt there was little point in consulting a doctor for forgetfulness. Many thought that seeing a GP was only for severe problems. Some said that their culture was secretive and highly valued privacy of personal affairs and therefore did not want to discuss what they regarded as a private and stigmatising problem with a GP. Participants did not appreciate their GP could refer to memory services who have more time and expertise. They were concerned about harm from medication and compulsory institutionalisation. Care should be from the family. Any intervention should emphasise the legitimacy of seeing a doctor early for memory concerns, that dementia is a physical illness which also occurs in the Black community, that help and time are available from memory services whose role is to prolong independence and support families in caring.     

Qualitative Evaluation of Advanced Care Planning in Early Dementia (ACP-ED)

Background

End-of-life-care is often poor in individuals with dementia. Advanced care planning (ACP) has the potential to improve end-of-life care in dementia. Commonly ACP is completed in the last six months of life but in dementia there may be problems with this as decision-making capacity and ability to communicate necessarily decrease as the disease progresses. Choosing the right time to discuss ACP with people with dementia may be challenging given the duration of the illness may be up to nine years.

Aims

To explore the acceptability of discussing ACP with people with memory problems and mild dementia shortly after diagnosis.

Methods

In-depth interviews were conducted with 12 patients and eight carers who had participated in ACP discussions and six staff members from a memory clinic and a community mental health team who had either conducted or attended the discussions for training purposes.

Results

Patients and carers found ACP a positive intervention that helped them think about the future, enabled people with dementia to make their wishes known, and resulted in their feeling relieved and less worried about the future. The importance of sharing the ACP documentation between health service providers was highlighted.

Conclusions

This qualitative evaluation of ACP in early dementia has encouragingly positive results which support the wider application of the intervention in memory services and community mental health teams. Strategies are suggested to support the implementation of ACP further in clinical practice.     

Rehabilitación geriátrica multidisciplinar en el paciente con fractura de cadera y demencia

Hip fracture and dementia rates increase with age, and both groups of patients suffer increased morbidity and mortality and functional impairment. The management of these patients is a challenge for the orthogeriatric and rehabilitation team process, as despite the evidence on the benefit, the results analysed are still worse than in patients without cognitive impairment. For this reason, and due to the limitation in health resources, many of them have problems in accessibility to them, or are limited to a less intense rehabilitation. There are insufficient studies on the best rehabilitation interventions in this group of patients, but it is suggested: 1) to use a multidisciplinary rehabilitation model adapted to the patient with dementia, and 2) to redefine results of the rehabilitation of these patients not only in terms of functional improvement, without highlighting other concepts, such as quality of life, decrease in complications or improved social support.     

Is sympathetic activation by stressful memories linked to the occurrence of hypertension and metabolic syndrome?

This paper is based on reported links between dementia and hypotension. Large clinical studies report that patients with Alzheimer's disease normalize previously elevated blood pressure. Among previously hypertensive, elderly persons, an unexpected minority of hypotensive elderly patients with cognitive decline has been found. A possible interpretation is that patients of both groups, instead of having cognition problems due to arterial hypotension, might have become hypotensive because they can no longer remember and worry about stress-inducing problems that have vanished from their memories.I propose that memory induced stress reactions increase the resting sympathetic tone, vascular resistance, secretion of renin and contrainsulary hormones. Dementia reduces this source of chronic stress reaction, and hence reduction on sympathetic activation could explain both the reduction in blood pressure and relief from insulin resistance. This might explain how is it possible that blocking of sympathetic activity and renin–angiotensin system prolongs human life, despite importance of these mechanisms in maintaining circulatory homeostasis in all mammals.     

Alzheimer's dementia: current data review

The review focuses on current data on Alzhemier's dementia, a clinical syndrom characterised with acquired deterioration of cognitive functioning and emotional capacities, which impaires everyday activity and quality of life. Alzheimer's dementia is the most common type of dementia in clinical surveys. The diagnosis of Alzheimer's dementia is primarily based on symptoms and signs and memory impairment is clinically most significant. Cholinesterase inhibitors -donepezil, rivastigmine and galantamine are considered to be the first line pharmacotherapy for mild to moderate Alzheimer's disease. Currently, no effective pharmacologic interventions have been researched enough to support their use in prevention of Alzheimer's dementia. Studies suggest that healthy lifestyle, ongoing education, regular physical activity, and cholesterol control, play a role in prevention of Alzheimer's dementia.     

Psychosocial group intervention to enhance self-management skills of people with dementia and their caregivers: study protocol for a randomized controlled trial

ABSTRACT: BACKGROUND: After diagnosis of a dementing illness patients and their spouses have many concerns related to the disease and their future. This often leads to poor psychological well-being and reduced health related quality of life (HRQoL) of the family. Support for self-management skills has been proven to be an effective method to improve prognosis of asthma, heart failure and osteoarthritis. However, self-management interventions have not been studied in dementia. Therefore, our aim was to examine in an objective-oriented group intervention the efficacy of self-management support program (SMP) on the HRQoL of dementia patients and their spousal caregivers as well as on the sense of competence and psychological well-being of care-givers. METHODS: During the years 2011-12, 160 dementia patients and their spouses will be recruited from memory clinics and randomized into two arms: 80 patients for group-based SMP sessions including topics selected by the participants, 80 patients will serve as controls in for usual community care. Sessions may include topics on dementia, community services, active lifestyle and prevention for cognitive decline, spousal relationship, future planning and emotional well-being. The patients and spouses will have their separate group sessions (10 participants/group) once a week for 8 weeks. Main outcome measures will be patients' HRQoL (15D) and spousal caregivers' HRQoL (RAND-36), and sense of competence (SCQ). Secondary measures will be caregivers' psychological well-being (GHQ-12) and coping resources, patients' depression, cognition and signs of frailty. Data concerning admissions to institutional care and the use and costs of health and social services will be collected during a two year follow-up. DISCUSSION: This is a "proof -of-concept" study to explore the efficacy of group support for self-management skills among dementia families. It will also provide data on cost-effectiveness of the intervention.     

Education about dementia. Effectiveness of a public lecture

Memory and dementia are often topics of educational activities, however there is only limited information about the effectiveness of this education. In this study the effectiveness of a lecture, as part of a series of lectures about dementia, has been evaluated. The results showed an improvement in knowledge after the lecture and the participants were satisfied afterwards. Finally, it showed that there is a need for this kind of education; for professionals and for people who were worried about their memory or their partners' memory.     

A case for a non-transgenic animal model of Alzheimer's disease

Alzheimer's disease (AD) is associated with an early impairment in memory and is the major cause of dementia in the elderly. beta-Amyloid (Abeta) is believed to be a primary factor in the pathogenic pathway leading to dementia. Mounting evidence suggests that this syndrome begins with subtle alterations in synaptic efficacy prior to extensive neuronal degeneration and that the synaptic dysfunction could be caused by diffusible oligomeric assemblies of Abeta. This paper reviews the findings from behavioral analysis, electrophysiology, neuropathology and nootropic drug screening studies involving exogenous administration of Abeta in normal rodent brains. This non-transgenic model of amyloid pathology in vivo is presented as a complementary alternative model to transgenic mice to study the cellular and molecular pathways induced by amyloid, which in turn may be a causal factor in the disruption of cognition. The data reviewed here confirm that the diffusible form of Abeta rapidly induces synaptic dysfunction and a secondary process involving cellular cascades induced by the fibrillar form of amyloid. The time-course of alteration in memory processes implicates at least two different mechanisms that may be targeted with selective therapies aimed at improving memory in some AD patients.     

Prevalence of potentially reversible dementias and actual reversibility in a memory clinic cohort

BACKGROUND: Although clinics for the evaluation of cognitive dysfunction have typically emphasized the detection and treatment of the reversible causes of dementia, it remains unclear whether the treatment of such causes results in reversal of the dementia. Therefore, the appropriate work-up for dementia is in dispute. METHODS: A chart review was performed with records from an urban tertiary care referral-based memory clinic. The records for 196 patients with dementia or suspected dementia, seen between October 1991 and December 1993, were examined to determine the prevalence of potentially reversible dementias and whether the cognitive dysfunction improved or resolved after treatment. Data abstracted from the medical charts included demographic information, medication use, presence of depression, and results of neuropsychological tests, blood work and neuroimaging. The clinical diagnosis, the response to treatment, if applicable, and the outcome (mean follow-up period 16 months) were analysed. The recommendations of the 1989 Canadian Consensus Conference on the Assessment of Dementia (CCCAD) on the use of CT were retrospectively applied in each case. RESULTS: Of the 196 patients, 45 (23.0%) had a potentially reversible condition identified by history, physical examination, blood testing or CT; in only 7 (3.6% of the total) did treatment result in improvement or resolution of the dementia. These 7 patients had higher results for the Mini-Mental State examination (mean result 26) and exhibited only mild cognitive deficits. Potentially reversible lesions were found in the CT scans of 6 (3.1%) patients: 4 had normal-pressure hydrocephalus and 2 had a brain tumour. If the CCCAD recommendations had been followed, CT would have been performed in 76 (38.8%) of the patients, and 1 of the 6 patients with a lesion would have been missed. INTERPRETATION: Both potential and actual reversibility of dementia was low in these memory clinic patients. The patients whose condition improved with intervention had early and milder cognitive deficits, which suggests that thorough evaluation of early memory loss is warranted.     

Rationale and design of a double-blind, placebo-controlled, randomized trial to evaluate the safety and efficacy of nimodipine in preventing cognitive impairment in ischemic cerebrovascular events (NICE)

ABSTRACT: BACKGROUND: Stroke is the second most common cause of mortality and the leading cause of neurological disability, cognitive impairment and dementia worldwide. Nimodipine is a dihydropyridinic calcium antagonist with a role in neuroprotection, making it a promising therapy for vascular cognitive impairment and dementia. METHODS: The NICE study is a multicenter, randomized, double-blind, placebo-controlled study being carried out in 23 centers in China. The study population includes patients aged 30--80 who have suffered an ischemic stroke (<=7 days). Participants are randomly allocated to nimodipine (90 mg/d) or placebo (90 mg/d). The primary efficacy is to evaluate the level of mild cognitive impairment following treatment of an ischemic stroke with nimodipine or placebo for 6 months. Safety is being assessed by observing side effects of nimodipine. Assuming a relative risk reduction of 22 %, at least 656 patients are required in this study to obtain statistical power of 90 %. The first patient was recruited in November 2010. DISCUSSION: Previous studies suggested that nimodipine could improve cognitive function in vascular dementia and Alzheimer's disease dementia. It is unclear that at which time-point intervention with nimodipine should occur. Therefore, the NICE study is designed to evaluate the benefits and safety of nimodipine, which was adminstered within seven days, in preventing/treating mild cognitive impairment following ischemic stroke.     

Physostigmine effects in Alzheimer's disease: relationship to dementia severity

Eleven demented patients were administered .004, .009, and .013 mg/kg physostigmine intramuscularly, and placebo, double-blind, in Phase 1. The most effective dose, in terms of showing the best memory score as compared to saline, was repeated during Phase 2. Five patients improved their verbal memory scores in both Phases 1 and 2 after the most effective dose of physostigmine; these five "responders" were found to be significantly more demented than the six "nonresponders." Drug-induced increases in memory scores were significantly correlated with illness severity. Intrusions, which were not a factor in selection of the most effective dose, were reduced in the group as a whole, with the responders showing the most improvement and the nonresponders the least. The association between physostigmine effect and degree of dementia suggests to us that the severe cases may have more permeable blood-brain barriers, and that drug availability to the brain is an important factor in evaluating treatment of SDAT with cholinergic substances.     

The Effects of Hand Massage on Stress and Agitation Among People with Dementia in a Hospital Setting: A Pilot Study

Agitation in people with dementia is a growing concern as it causes distress for both patients and their nurses and may contribute to relational disorders. Previous studies involving patients with dementia living in long-term care facilities have reported decreased agitation following massage. The objective of this pilot study was to investigate the effect of hand massage on agitation and biological markers of stress in patients with dementia hospitalized in an acute geriatric psychiatry service. In this randomized controlled trial we included 40 agitated patients with dementia with an intervention group and a control group. The study is designed to test the effect of seven hand massages over three continuous weeks on agitation and levels of salivary cortisol (sC) and alpha-amylase (sAA). Compared to the control group, the intervention group exhibited larger increases in sC and sAA at week 1 from before to after the massage, but larger decreases at week 2 and 3, with a significant group effect for sAA at week 2. Agitation scores were not significantly different between the groups but tended to decrease more in the intervention group than the control group. This study provides first encouraging results suggesting that hand massage might have beneficial effects on stress and agitation in hospitalized patients with dementia. It also highlights the challenges associated with conducting such studies with this complex patient population. Further studies are needed to confirm these findings and the benefits of hand massage as part of routine care for patients with dementia.     

Vascular Cognitive Disorder. A Biological and Clinical Overview

Although vascular dementia (VaD) represents the second most common cause of dementia after Alzheimer’s disease (AD) in the elderly, and is referred as the “silent epidemic of the twenty-first century”, there is still a controversy on terminology, classification and diagnostic criteria of VaD. The diagnosis of VaD resides in clinical criteria determining a cognitive impairment, the presence of cerebrovascular disease and, only in the case of post-stroke dementia or multi-infarct dementia, a temporal relationship between these. The search for a reliable biochemical tests helping in the diagnosis of VaD is so far not available. Several vascular risk factors have a role in the development of VaD and their identification and treatment are among the major aspects of management of VaD. A new line of research in this field is the study of genetic factors underlying vascular cognitive impairment which are: (1) genes predisposing to cerebrovascular disease, and (2) genes that influence brain tissue responses to cerebrovascular lesions. Evidence in favour of a coexistence of vascular and degenerative components in the pathogenesis of dementia in an elderly population comes from neuropathological and epidemiological studies. There is now a great debate whether VaD and AD are more than common coexisting unrelated pathologies and, instead, represent different results of synergistic pathological mechanisms. Preventive approaches aiming at reducing incident VaD by targeting patients at risk of cerebrovascular disease (primary prevention), or acting on patients after a stroke (secondary prevention) to prevent stroke recurrence and the progression of brain changes associated with cognitive impairment are mandatory therapeutic strategies.     

基于体素的形态测量学在阿尔茨海默病及轻度认知功能障碍研究中的应用

阿尔茨海默病(Alzheimer's disease,AD)是发生于老年和老年前期、以进行性认知功能障碍和行为异常为特征的中枢神经系统退行性疾病,是老年痴呆中最常见类型。轻度认知功能障碍(mild cognitive impairment,MCI)是介于正常衰老和痴呆之间的一种中间状态,指有轻度的记忆或认知损伤,但尚未达到痴呆程度的一种状态,日常生活和社会功能不受影响,其中很大一部分患者最终进展为AD。临床诊断AD患者多已达中晚期,为了能早期诊断AD及预测MCI的转归,有关AD的生物学标注物的研究成为近年来的科研热点。AD患者颅脑的大体病理特征为脑萎缩,其萎缩有别于正常老龄化所致的退行性改变,有其自身特点,这种特定形式的萎缩有可能成为AD早期诊断的生物学标志物。基于体素的形态测量学(voxel-based morphometry,VBM)是一种基于像素水平对脑核磁图像进行自动、全面、客观分析的技术,可以定量分析全脑结构、刻画出局部脑区结构特征,是一种较好的脑形态分析工具,广泛用于阿尔茨海默病及轻度认知功能障碍的研究中,本文综述了近年来其研究进展,期望为临床及科研提供参考。     

Life- and person-centred help in Mecklenburg-Western Pomerania, Germany (DelpHi): study protocol for a randomised controlled trial

ABSTRACT: BACKGROUND: The provision of appropriate medical and nursing care for people with dementia is a major challenge for the healthcare system in Germany. New models of healthcare provision need to be developed, tested and implemented on the population level. Trials in which collaborative care for dementia in the primary care setting were studied have demonstrated its effectiveness. These studies have been conducted in different healthcare systems, however, so it is unclear whether these results extend to the specific context of the German healthcare system. The objective of this population-based intervention trial in the primary care setting is to test the efficacy and efficiency of implementing a subsidiary support system on a population level for persons with dementia who live at home. Methods and study design The study was designed to assemble a general physician-based epidemiological cohort of people above the age of 70 who live at home (DelpHi cohort). These people are screened for eligibility to participate in a trial of dementia care management (DelpHi trial). The trial is a cluster-randomised, controlled intervention trial with two arms (intervention and control) designed to test the efficacy and efficiency of implementing a subsidiary support system for persons with dementia who live at home. This subsidiary support system is initiated and coordinated by a dementia care manager: a nurse with dementia-specific qualifications who delivers the intervention according to a systematic, detailed protocol. The primary outcome is quality of life and healthcare for patients with dementia and their caregivers. This is a multidimensional outcome with a focus on four dimensions: (1) quality of life, (2) caregiver burden, (3) behavioural and psychological symptoms of dementia and (4) pharmacotherapy with an antidementia drug and prevention or suspension of potentially inappropriate medication. Secondary outcomes include the assessment of dementia syndromes, activities of daily living, social support health status, utilisation of health care resources and medication. DISCUSSION: The results will provide evidence for specific needs in ambulatory care for persons with dementia and will show effective ways to meet those needs. Qualification requirements will be evaluated, and the results will help to modify existing guidelines and treatment paths. Trial registration NCT01401582.     

Melatonin Attenuates Scopolamine-Induced Memory/Synaptic Disorder by Rescuing EPACs/miR-124/Egr1 Pathway

Alzheimer’s disease (AD) is the most prevalent type of dementia in elderly people. There are decreased melatonin levels in the serum of AD patients, and melatonin supplements are able to reverse AD pathology and memory deficits in many animal experiments and clinical trials. However, the underlying mechanism regarding how melatonin rescues the AD-like memory/synaptic disorder remains unknown. Here, we use the Morris water maze, step-down inhibitory avoidance task, in vivo long-term potentiation recording, and Golgi staining and report that intraperitoneal injection of melatonin (1 mg/kg/day) for 14 days in rats effectively reverses the memory and synaptic impairment in scopolamine-induced amnesia, a well-recognized dementia animal model. Using real-time polymerase chain reaction and western blotting experiments, we further determined that melatonin rescues the EPACs/miR-124/Egr1 signal pathway, which is important in learning and memory, as reported recently. Our studies provide a novel underlying epigenetic mechanism for melatonin to attenuate the synaptic disorder and could benefit drug discovery in neurodegenerative diseases.     

Mind your teeth—The relationship between mastication and cognition

This article explores the multifactorial relationship between mastication and cognition, with a focus on dementia. Older persons, especially those with dementia, are at great risk of suffering from oral health problems such as orofacial pain and loss of natural teeth. A possible explanation could be that the cognitive and motor impairments resulting from dementia cause a decrease in self‐care and as such, a worsening of oral health. An alternative explanation is that cognition and oral health influence each other. Animal studies show that a decrease in masticatory activity, for example, due to a soft diet or loss of teeth, causes memory loss and neuronal degeneration. The relationship between mastication and cognition has also been researched in human studies, but a cause‐effect relationship has not been proven. It is likely that multiple factors play a role in this relationship, such as self‐care, nutrition, stress and pain.