Mild cognitive impairment in general practice: age-specific prevalence and correlate results from the German study on ageing, cognition and dementia in primary care patients (AgeCoDe)

BACKGROUND: Although mild cognitive impairment (MCI) represents a high-risk factor for developing dementia, little is known about the prevalence of MCI among patients of general practitioners (GPs). AIMS: Estimation of age-specific prevalence for original and modified concepts of MCI and their association with sociodemographic, medical and genetic (apoE epsilon4 genotype) factors among patients of GPs. METHODS: A GP practice sample of 3,327 individuals aged 75+ was assessed by structured clinical interviews. Results: Prevalence was 15.4% (95% CI = 14.1-16.6) for original and 25.2% (95% CI = 23.7-26.7) for modified MCI. Rates increased significantly with older age. Positive associations were found for apoE epsilon4 allele, vascular diseases and depressive symptoms. CONCLUSION: MCI is frequent in elderly patients of GPs. GPs have a key position in secondary prevention and care of incipient cognitive deterioration up to the diagnosis of dementia.     

The impact of anxiety on the progression of mild cognitive impairment to dementia in Chinese and English data bases: a systematic review and meta‐analysis

Objective

It remains unclear whether or not anxiety increases the risk of dementia in people with mild cognitive impairment (MCI). The aim of this systematic review and meta‐analysis was to investigate the risk of dementia among people with MCI and anxiety compared with those with MCI and no anxiety.

Methods

The hazard ratio of conversion to dementia in people with anxiety and MCI was compared with those without anxiety and was calculated using a generic inverse variance method with fixed effect models.

Results

Eleven studies from the English and Chinese databases were included, seven of which were included in the meta‐analysis. The pooled hazard ratio of conversion to dementia was 1.18 95% CI [1.07, 1.31] (p = 0.002) in the group of MCI plus anxiety compared with those without anxiety.

Conclusion

The results suggest that anxiety increases the risk of progression to dementia in people with MCI. Future interventions targeting anxiety management in vulnerable people with MCI may reduce the risk of dementia. Copyright © 2017 John Wiley & Sons, Ltd.     

Rate of progression of mild cognitive impairment to dementia – meta‐analysis of 41 robust inception cohort studies

Objective: To quantify the risk of developing dementia in those with mild cognitive impairment (MCI). Method: Meta‐analysis of inception cohort studies. Results: Forty‐one robust cohort studies were identified. To avoid heterogeneity clinical studies, population studies and clinical trials were analysed separately. Using Mayo defined MCI at baseline and adjusting for sample size, the cumulative proportion who progressed to dementia, to Alzheimer’s disease (AD) and to vascular dementia (VaD) was 39.2%, 33.6% and 6.2%, respectively in specialist settings and 21.9%, 28.9% and 5.2%, respectively in population studies. The adjusted annual conversion rate (ACR) from Mayo defined MCI to dementia, AD and VaD was 9.6%, 8.1% and 1.9%, respectively in specialist clinical settings and 4.9%, 6.8% and 1.6% in community studies. Figures from non‐Mayo defined MCI and clinical trials are also reported. Conclusion: The ACR is approximately 5–10% and most people with MCI will not progress to dementia even after 10 years of follow‐up.     

Clinical correlates of functional performance in community-dwelling Chinese older persons with mild cognitive impairment

ABSTRACTBackground: Increasing evidence suggests that functional impairment can be detected in older persons with mild cognitive impairment (MCI). This study explores the functional profiles and the clinical correlates of a population-based sample of Chinese older persons with MCI in Hong Kong.Methods: A random sample of 765 Chinese elderly subjects without dementia was recruited, of which 389 were elderly normal controls (Clinical Dementia Rating = 0), and 376 had questionable dementia (CDR = 0.5). The latter were categorized into an MCI group (n = 291) and a very mild dementia (VMD) group (n = 85). Their functional performances were measured and compared with the normal controls (NC). Multiple regression analyses investigated the associations between functional scores (Disability Assessment in Dementia) and clinical correlates (cognitive test scores, neuropsychiatric symptoms and motor signs) in the NC subjects and cognitively impaired subjects.Results: Subjects with MCI had intermediate functional performance between the NC and those with VMD. Regression analyses revealed that lower scores of cognitive tests (delayed recall and categorical verbal fluency tests), apathy, aberrant motor symptoms and parkinsonism features were associated with lower functional scores in clinically non-demented subjects. Functional scores had no correlation with age, education and medical illness burden.Conclusion: Neuropsychiatric symptoms and parkinsonism features were associated with functional impairment in the clinically non-demented elderly in the community. Assessment of these should be incorporated in the evaluation of older persons for early cognitive impairment.     

Neuropsychiatric symptoms in South‐East Asian patients with mild cognitive impairment and dementia: prevalence,subtypes, and risk factors

Background

The subtypes and risk factors of neuropsychiatric symptoms remain largely unexplored in South‐East Asian populations.

Objective

We investigated the prevalence, subtypes, and risk factors, namely, demographic, medical morbidity, and cognitive impairment associated with neuropsychiatric symptoms in a South‐East Asian cohort of patients with mild cognitive impairment (MCI) and dementia.

Methods

A clinical cohort of 38 MCI and 198 mild–moderate dementia patients were assessed using the Neuropsychiatric Inventory‐Questionnaire.

Results

Neuropsychiatric symptoms were equally prevalent among patients with MCI (74%) and mild–moderate dementia (85%). Three subtypes of symptoms were identified for each diagnostic group; for MCI, they included mood disturbances, anxiety/sleep problems, and psychosis, while for dementia, the subtypes included behavioral disturbances, psychosis/mood, and hyperactive behaviors. The largest risk for neuropsychiatric symptoms for both MCI and dementia patients was male gender. Among patients with MCI, burden of cerebrovascular disease and global cognitive impairment were small risks for neuropsychiatric symptoms, while for patients with dementia, an older age (>65 years) was a small risk and lower educational attainment was a moderate risk.

Discussion

These findings contribute to the worldwide epidemiology of neuropsychiatric symptoms in MCI and dementia and highlight that the profile of symptoms, subtypes, and risks is fairly homogenous across Western and Asian cultures. Copyright © 2017 John Wiley & Sons, Ltd.     

Mild cognitive impairment and everyday functioning in older adults

The relations between mild cognitive impairment without dementia (MCI/CIND) and everyday functional abilities were examined using data from the Canadian Study of Health and Aging (CSHA). Individuals were identified with MCI/CIND if both caregiver report and clinician judgment agreed on the presence of cognitive impairment in the absence of dementia. Cross-sectional and longitudinal comparisons indicated that individuals with MCI/CIND demonstrated a broad range of impairment in instrumental activities of daily living (IADL) compared to individuals with no cognitive impairment (NCI). In cross-sectional analyses, neuropsychological measures of memory and psychomotor speed were significantly related to impairment in eight areas of functioning. In addition, poorer memory performance was significantly predictive of future impairment in money management.     

Mild cognitive impairment and everyday functioning in older adults

The relations between mild cognitive impairment without dementia (MCI/CIND) and everyday functional abilities were examined using data from the Canadian Study of Health and Aging (CSHA). Individuals were identified with MCI/CIND if both caregiver report and clinician judgment agreed on the presence of cognitive impairment in the absence of dementia. Cross-sectional and longitudinal comparisons indicated that individuals with MCI/CIND demonstrated a broad range of impairment in instrumental activites of daily living (IADL) compared to individuals with no cognitive impairment (NCI). In cross-sectional analyses, neuropsychological measures of memory and psychomotor speed were significantly related to impairment in eight areas of functioning. In addition, poorer memory performance was significantly predictive of future impairment in money management.     

Defining mild cognitive impairment in Parkinson's disease

Our purpose was to characterize a state of mild cognitive impairment (MCI) in Parkinson's disease (PD) (PD‐MCI) that would be analogous to the MCI that is posited as a precursor of Alzheimer's disease (AD). We categorized 86 PD subjects in a brain bank population as either cognitively normal (PD‐CogNL), PD‐MCI using criteria that included a 1.5 standard deviation or greater deficit upon neuropsychological testing consistently across at least one cognitive domain without dementia, and PD dementia (PD‐D) using DSM‐IV criteria. Twenty‐one percent of our PD sample met criteria for PD‐MCI, 62% were PD‐CogNL, and 17% had PD‐D. The mean duration of PD and MMSE scores of the PD‐MCI group were intermediate and significantly different from both PD‐CogNL and PD‐D. The cognitive domain most frequently abnormal in PD‐MCI was frontal/executive dysfunction followed by amnestic deficit. Single domain PD‐MCI was more common than PD‐MCI involving multiple domains. We conclude that a stage of clinical cognitive impairment in PD exists between PD‐CogNL and PD‐D, and it may be defined by applying criteria similar to the MCI that is posited as a precursor of AD. Defining PD‐MCI offers an opportunity for further study of cognitive impairment in PD and targets for earlier therapeutic intervention. © 2007 Movement Disorder Society     

Working criteria of mild cognitive impairment in community: findings from Gwangju Dementia and Mild Cognitive Impairment Study (GDEMCIS)

Introduction: The clinical determination of relative severity of impairment along the spectrum of mild cognitive impairment (MCI) may be valuable for the prediction of dementia. The purpose of the present study is to suggest the working criteria of MCI based on severity in the community sample. Methods: The MCI group was divided into three groups by severity according to cognitive and functional status. The grade I MCI group was based on the original concept of Petersen's MCI. The grade II MCI group was in the same condition as grade I MCI, except that the general cognitive function was not intact. The grade III MCI group was defined as the condition not essentially preserved instrumental to the activity of daily living, but not definite in dementia regardless of general cognitive and functional state. Results: A total of 38.5% of the subjects were classified as not cognitively impaired (NCI), 41.4% as MCI, and 10.3% as having dementia. Preliminary results showed that the grades I, II, and III MCI groups had a tendency to lie between the NCI and dementia groups. Discussion: Prospective cohort studies with clinical correlations are needed to determine whether our working criteria of MCI considering characteristics of the rural elderly, such as low education and less comprehensive activities of daily living (ADL), would be useful.     

Prevalence and correlates of behavioral and psychiatric symptoms in community-dwelling elders with dementia or mild cognitive impairment: the Memory and Medical Care Study

BACKGROUND: Little is known about the prevalence and correlates of behavioral and psychiatric symptoms of dementia in community-dwelling elders with dementia or mild cognitive impairment (MCI). METHODS: 512 people with Mini-Mental State Examination (MMSE) scores < 24 or a decline of at least 4 points over two administrations, and their knowledgeable informants (KIs) were enrolled in the MMCS. The classification of subjects as having dementia or MCI was based on a neuropsychological battery of four tests, not a clinical diagnostic evaluation. The sample for this study included 454 subjects (dementia n = 333; MCI n = 121) and their KIs. Demographic and health-related characteristics of subjects and KIs were obtained during KI interviews. Multivariate logistic regression was used in statistical analysis. RESULTS: Compared to dementia subjects, those classified as MCI had a lower prevalence (47.1% vs 66.1%) of any symptoms (psychosis, depression, or agitation), and of agitation (24.8% vs 45.1%). Symptoms of psychosis and depression also were less prevalent, even though differences did not reach statistical significance. In the dementia group symptoms were associated with a report of a physician's diagnosis of dementia, greater functional impairment, and a KI who was a child/child-in-law. In those with MCI, symptoms were correlated with being white, greater functional impairment, and a younger, less educated, KI. CONCLUSIONS: Psychiatric and behavioral symptoms were common in community-residing elders with cognitive impairment, but their prevalence and correlates differed by study classification as having dementia or MCI. Identifying and treating these symptoms may benefit patients with cognitive impairment and their families. Longitudinal studies on the predictors, changes in prevalence, and effectiveness of treatments for psychopathology of dementia are needed.     

Conceptualization of mild cognitive impairment: a review

BACKGROUND: Several factors have prompted renewed interest in the concept of declines in cognitive function that occur in association with aging, in particular the area between normal cognition and dementia. We review the changing conceptualization of what has come to be known as mild cognitive impairment (MCI) in an effort to identify recent developments and highlight areas of controversy. METHODS: Standard MEDLINE search for relevant English-language publications on mild cognitive impairment and its associated terms, supplemented by hand searches of pertinent reference lists. RESULTS: Many conditions cause cognitive impairment which does not meet current criteria for dementia. Within this heterogenous group, termed 'Cognitive Impairment, No Dementia' (CIND), there are disorders associated with an increased risk of progression to dementia. Still, the conceptualization of these latter disorders remains in flux, with variability around assumptions about aging, the relationship between impairment and disease, and how concomitant functional impairment is classified. Amongst patients with MCI, especially its amnestic form, many will progress to Alzheimer's disease (AD). In contrast with clinic-based studies, where progression is more uniform, population-based studies suggest that the MCI classification is unstable in that context. In addition to Amnestic Mild Cognitive Impairment (AMCI), other syndromes exist and can progress to dementia. For example, an identifiable group with vascular cognitive impairment without dementia shows a higher risk of progression to vascular dementia, Alzheimer's disease and mixed dementia. CONCLUSIONS: Recent attempts to profile patients at an increased risk of dementia suggest that this can be done in skilled hands, especially in people whose symptoms prompt them to seek medical attention. Whether these people actually have early AD remains to be determined. The more narrowly defined MCI profiles need to be understood in a population context of CIND.     

Revised criteria for mild cognitive impairment: validation within a longitudinal population study

BACKGROUND: Mild cognitive impairment (MCI) refers to the transitional zone between normal ageing and dementia. Current criteria perform poorly within the general population setting. Revisions have been proposed based on results obtained from clinical and epidemiological studies. OBJECTIVE: To evaluate revised diagnostic criteria for mild cognitive impairment (MCI-R) incorporating changes in activity level and non-mnesic cognitive functioning. METHOD: MCI-R subjects were recruited from a representative network of general practitioners in the south of France. A computerized neuropsychometric examination was given. At 2 years of follow-up, a diagnosis of dementia was made by a neurologist using DSM-IIIR criteria and without knowledge of the results of the cognitive testing. Rates of conversion to incident dementia were assessed by receiver operating characteristics analysis. RESULTS: The MCI-R prevalence was found to be 16.6% using revised criteria. A significantly better prediction of transition to dementia (AUC = 0.80, sensitivity: 95%, specificity: 66%) was obtained with MCI-R than with the previous MCI criteria (AUC = 0.48, sensitivity: 5%, specificity: 91%). The predictive power was found to increase when MCI subtypes were combined. CONCLUSION: Incorporating the possibility of change in activity level and alteration of non-mnesic cognitive functions have been found to ameliorate the original algorithm and better define subjects converting to dementia. This definition may be applicable to both clinical and population research.     

Caregiving burden and psychiatric morbidity in spouses of persons with mild cognitive impairment

BACKGROUND: While the deleterious psychosocial and mental health effects of dementia caregiving are firmly established, very little is known about the burdens or psychiatric outcomes of providing care to a spouse with less severe cognitive impairment, such as mild cognitive impairment (MCI). We characterized the nature and level of caregiver burden and psychiatric morbidity in spouses of persons diagnosed with MCI. METHODS: Interview assessments were completed on a cohort of 27 spouses of persons with a recent diagnosis of MCI. Patient medical records were reviewed to collect information regarding the MCI patient's medical history. RESULTS: Respondents endorsed elevated levels of both task-related responsibilities and subjective caregiver burden. Depression and anxiety symptom levels also showed some elevations. Measures of caregiver burden were significantly associated with depression and anxiety levels. In particular, even after controlling for demographic risk factors for distress, nursing task burden was correlated with elevated depressive symptoms, and greater lifestyle constraints were correlated with higher anxiety levels. CONCLUSIONS: Although caregiver burden and psychiatric morbidity levels were lower than those typically observed in family dementia caregiving samples, our findings suggest that MCI caregivers have already begun to experience distress in association with elevated caregiving burden. These individuals may be ideal targets for selective preventive interventions to maximize their psychological well-being as caregiving burdens related to their spouses' cognitive impairment increase.     

Vascular cognitive disorder: a new diagnostic category updating vascular cognitive impairment and vascular dementia

Vascular cognitive impairment (VCI) was proposed as an umbrella term to include subjects affected with any degree of cognitive impairment resulting from cerebrovascular disease (CVD), ranging from mild cognitive impairment (MCI) to vascular dementia. VCI may or may not exclude the host of "focal" circumscribed impairments of specialized functions such as language (aphasia), intentional gesture (apraxia), or categorical recognition (agnosia), among others, that may result from a stroke. Therefore, there are no universally accepted diagnostic criteria for VCI. We conclude that this concept could be more useful if it were to be limited to cases of vascular MCI without dementia, by analogy with the concept of amnestic MCI, currently considered the earliest clinically diagnosable stage of Alzheimer disease (AD). In agreement with our view,the Canadian Study on Health and Aging successfully implemented a restricted definition of VCI, excluding cases of dementia (i.e., vascular cognitive impairment no dementia, VCI-ND). The Canadian definition and diagnostic criteria could be utilized for future studies of VCI. This definition excludes isolated impairments of specialized cognitive functions.Vascular dementia (VaD): The main problem of this diagnostic category stems from the currently accepted definition of dementia that requires memory loss as the sine qua non for the diagnosis. This may result in over-sampling of patients with AD worsened by stroke (AD+CVD). This problem was minimized in controlled clinical trials of VaD by excluding patients with a prior diagnosis of AD, those with pre-existing memory loss before the index stroke, and those with amnestic MCI. We propose a definition of dementia in VaD based on presence of abnormal executive control function, severe enough to interfere with social or occupational functioning. Vascular cognitive disorder (VCD): This term, proposed by Sachdev [P. Sachdev, Vascular cognitive disorder. Int J Geriat Psychiatry 14 (1999)402-403.] would become the global diagnostic category for cognitive impairment of vascular origin, ranging from VCI to VaD. It would include specific disease entities such as post-stroke VCI, post-stroke VaD, CADASIL, Binswanger disease, and AD plus CVD. This category explicitly excludes isolated cognitive dysfunctions such as those mentioned above.     

Mild cognitive impairment in a population-based epidemiological study

Background: It would be of considerable importance to be able to estimate the rate at which subjects with mild cognitive impairment (MCI) progress to dementia in a cohort of a population‐based epidemiological study and to establish simple diagnostic methods for the identification of people at high‐risk of dementia. Subjects in a community based elderly cohort of MCI were followed longitudinally. Methods: Subjects were selected from participants in the first epidemiological study conducted on all persons aged 65 years and older residing at home in Nakayama, Japan, using the Mini‐Mental State Examination (MMSE). Mild cognitive impairment was defined as memory deficit with objective memory assessment, without dementia, impairment of general cognitive function or disability in activities of daily living. The conversion rate was calculated using the person–year method. Results: At baseline, the sample consisted of 104 subjects selected from 1162 community dwellers aged over 65 years of age. During the 5‐year follow up, 11 subjects (10.6%) were diagnosed with Alzheimer's disease (AD), five (4.8%) were diagnosed with vascular dementia (VaD) and six (5.8%) were diagnosed with dementia of other etiology. In this survey, the annual conversion rate of MCI to AD was calculated as 8.5% per 100 person–years and shifted to dementia at a rate of 16.1% per 100 person–years. The proportion of subjects with MCI who progressed to develop dementia was the same as in previous reports. However, nearly 40% of subjects returned to normal. Conclusion: The MCI concept, as currently defined, is an unstable and heterogeneous group.     

Preclinical dementia: an Italian multicentre study on amnestic mild cognitive impairment

BACKGROUND: Different rates and cognitive predictors of conversion to dementia have been reported in subjects with different kinds of mild cognitive impairment (MCI). METHODS: A prospective, 24-month follow-up study, involving 269 subjects who strictly fulfilled criteria for the amnestic MCI. RESULTS: Conversion rate to dementia was 21.4% per year. Seventy-nine out of the 83 individuals who developed dementia were affected by probable Alzheimer's disease (AD). Among others, at the 24-month follow-up 24.1% were still affected by amnestic MCI, 13.3% had changed their neuropsychological profile of impairment and 17.2% were cognitively normalised. Compared to subjects who did not convert to AD, those who did convert showed poorer immediate and delayed recall and recognition of verbal and visual material at baseline as well as reduced executive abilities. A combination of age, Clinical Dementia Rating boxes and scores on delayed recall and recognition of verbal and visual material accurately identified 86% of the subjects who developed AD. CONCLUSIONS: Elderly subjects affected by an isolated memory disorder have a high probability of developing AD. The ability of verbal and visual measures to predict incipient dementia of memory impairment may be increased by the simultaneous assessment of individual features, such as age or rate of functional impairment.     

Neuropsychiatric symptoms in older people with and without cognitive impairment

Neuropsychiatric symptoms (NPS) are non-cognitive disturbances such as depression. Rates of NPS have been shown to increase as cognitive ability declines and may be useful in predicting transition from mild cognitive impairment (MCI) to dementia. This community-based study reports the association between NPS and cognitive decline over two years. Participants included 873 community dwelling adults aged 70-90 years enrolled in the Sydney Memory and Ageing Study. NPS were assessed by the Neuropsychiatric Inventory (NPI). Cognitive impairment was defined by diagnosis (MCI or incident dementia) or neuropsychological test performance across five cognitive domains. Cognitive decline was defined by progression to dementia or worse neuropsychological performance. Total NPS at baseline did not differ between those without cognitive impairment (26.2%) and those with MCI (28.8%), but agitation and apathy were associated with MCI. Only baseline depression was associated with dementia at follow-up. Total NPS at baseline was cross-sectionally associated with cognitive impairment in executive function, attention, and global cognition, but did not predict cognitive decline. Depression, anxiety, agitation, anxiety, and apathy were all associated with impairment in at least one cognitive domain, but only anxiety and agitation were significantly associated with cognitive decline. Sensitivity analyses applied more stringent criteria for NPS and cognitive impairment in MCI but did not alter interpretation of results from the main analysis. Overall rates of NPS at baseline were not associated with MCI, dementia, or cognitive decline over two years. Additional follow-up is needed to further examine this association over a longer time course.     

Frequency and outcomes of primary central sleep apnea in a population-based study

BackgroundPrimary central sleep apnea (PCSA) is believed to be rare and data regarding its prevalence and long-term outcomes are sparse. We used the Rochester Epidemiology Project (REP) resources to identify all Olmsted County, Minnesota, residents with an incident diagnosis of PCSA and their clinical outcomes.MethodsWe searched the REP database for all residents with polysomnography (PSG)-confirmed diagnoses of central sleep apnea (CSA) between 2007 and 2015. From these, we reviewed the PSGs and medical records to find those who had PCSA based upon accepted diagnostic criteria. Data based on detailed review of the medical records, including all clinical notes and tests were recorded for analysis.ResultsOf 650 patients identified with CSA, 25 (3.8%; 23 male) had PCSA, which was severe in most patients (n = 16, 64%). Of those, 23 (92%) patients were prescribed and 18/23 (78.2%) adherent to positive airway pressure therapy. Median duration of follow-up was 4.4 years (IQR:4.2). Four (16%) patients were subsequently diagnosed with cardiac arrhythmias, one (4%) with unstable angina, two (8%) with heart failure, five (20%) with mild cognitive impairment (MCI)/dementia and two (8%) with depression. Six (25%) patients died (median time to death = 5 years; IQR:4.8), three of whom had Lewy body dementia.ConclusionsIn this population-based study, PCSA was rare and when present, was severe in a majority of patients. The mortality rate was high. Most frequently observed disorders during follow-up were mild cognitive impairment (MCI)/dementia followed by cardiac arrhythmias; it is possible that these entities were present and not recognized prior to the diagnosis of PCSA.     

Clinical correlates of Parkinsonian signs in community- dwelling Chinese older persons: a population based study

BACKGROUND AND OBJECTIVE: This study examined the clinical correlates of parkinsonian signs including neuropsychiatric symptoms, cognitive impairment and medical illness burden in the community-dwelling non-demented Chinese elderly. METHODS: A random sample of 765 Chinese elderly subjects from a thematic household survey was recruited. There were 389 normal elderly controls (Clinical Dementia Rating [CDR] 0) (NC) and 376 subjects with questionable dementia (CDR 0.5). The subjects with questionable dementia (CDR 0.5) were categorized into two groups: a MCI group (n = 291) and a very mild dementia (VMD) group (n = 85). Parkinsonian signs were measured by Unified Parkinson Disease Rating Scale- motor scale (UPDRS). The clinical correlates were investigated in each group. RESULTS: UPDRS motor score was associated with age, cumulative medical illness burden and cerebrovascular accidents in the normal control and MCI groups. It correlated negatively with MMSE scores in the NC group. It was associated with presence of soft signs in the NC and MCI groups; and apathy in the VMD group. CONCLUSION: Neuropsychiatric symptoms, cognitive impairment and vascular risk factors had different patterns of associations with parkinsonian signs in the older persons with different degree of cognitive impairment.