The Effect of Cognitive Impairment on the Association Between Social Network Properties and Mortality Among Older Korean Adults

OBJECTIVES

This study investigated the effect of cognitive impairment on the association between social network properties and mortality among older Korean adults.

METHODS

This study used data from the Korean Social Life, Health, and Aging Project. It obtained 814 older adults' complete network maps across an entire village in 2011-2012. Participants' deaths until December 31, 2020 were confirmed by cause-of-death statistics. A Cox proportional hazards model was used to assess the risks of poor social network properties (low degree centrality, perceived loneliness, social non-participation, group-level segregation, and lack of support) on mortality according to cognitive impairment.

RESULTS

In total, 675 participants (5510.4 person-years) were analyzed, excluding those with missing data and those whose deaths could not be verified. Along with cognitive impairment, all social network properties except loneliness were independently associated with mortality. When stratified by cognitive function, some variables indicating poor social relations had higher risks among older adults with cognitive impairment, with adjusted hazard ratios (HRs) of 2.12 (95% confidence interval [CI], 1.34 to 3.35) for social nonparticipation, 1.58 (95% CI, 0.94 to 2.65) for group-level segregation, and 3.44 (95% CI, 1.55 to 7.60) for lack of support. On the contrary, these effects were not observed among those with normal cognition, with adjusted HRs of 0.73 (95% CI, 0.31 to 1.71), 0.96 (95% CI, 0.42 to 2.21), and 0.95 (95% CI, 0.23 to 3.96), respectively.

CONCLUSIONS

The effect of social network properties was more critical among the elderly with cognitive impairment. Older adults with poor cognitive function are particularly encouraged to participate in social activities to reduce the risk of mortality.

Increased pulse wave velocity is related to impaired working memory and executive function in older adults with metabolic syndrome

Age-related vascular alterations promote the pathogenesis of vascular cognitive impairment (VCI). Cardiovascular risk factors that accelerate vascular aging exacerbate VCI. Metabolic syndrome (MetS) constitutes a cluster of critical cardiovascular risk factors (abdominal obesity, hypertension, elevated triglycerides, elevated fasting glucose, reduced HDL cholesterol), which affects nearly 37% of the adult US population. The present study was designed to test the hypotheses that MetS exacerbates cognitive impairment and that arterial stiffening moderates the association between cognitive dysfunction and MetS in older adults. MetS was defined by the NCEP ATP III guidelines. Cognitive function (digit span and trail-making tests) and brachial-ankle pulse wave velocity (baPWV; a non-invasive clinical measurement of arterial stiffness) were assessed in older adults with MetS and age- and sex-matched controls. Multiple linear regression models were applied to test for the main effects of MetS, baPWV, and their interaction on cognitive performance. Fifty-three participants with MetS (age: 68 ± 8 years) and 39 age-matched individuals without MetS (age: 66 ± 9 years) were enrolled into the study. In adjusted multivariable regression analyses of the digit span backward length score, both MetS (ß = 1.97, p = 0.048) and MetS by baPWV interaction (ß =  - 0.001, p = 0.026) were significant predictors. In participants with MetS, higher baPWV was associated with poorer performance on digit span backward length score, a test of working memory (R =  - 0.44, p = 0.0012), but there was no association in those without MetS (R = 0.035, p = 0.83). MetS was negatively associated with performance on the digit span backward length score, baPWV was negatively associated with multiple neuropsychological outcomes, and baPWV moderated the association between digit span backward length score and MetS, as individuals with both MetS and higher baPWV had the most impaired cognitive function. Our findings add to the growing body of evidence that individuals with MetS and higher baPWV may be prone to VCI.

Mild cognitive impairment, dementia and risk of mortality in essential tremor: A longitudinal prospective study of elders

BACKGROUND

There is evidence that the risk of mortality is increased in patients with essential tremor (ET), however, there are few longitudinal, prospective data on the predictors of mortality in ET. There is also evidence that ET is associated with cognitive impairment; yet, it is unknown whether this is associated with elevated risk of mortality.

METHODS

In a longitudinal, prospective study of 194 elders with ET, an extensive neuropsychological test battery was performed at three time points: baseline, 18 months, and 36 months, and cognitive diagnoses (normal, mild cognitive impairment [MCI], and dementia) were assigned during consensus conferences. We used Cox proportional hazards models to estimate hazard ratios (HR) for death.

RESULTS

The mean baseline age was 79.1 ± 9.7 years. During follow-up, 52 (26.8%) died. In initial univariate models, a variety of baseline factors were associated with increased risk of mortality, including demographic variables (i.e., older age), cognitive variables and gait and balance variables. In the final multivariate Cox model, baseline dementia (HR = 2.66, p = 0.006), older baseline age (HR = 1.18, p < 0.001), and more reported falls at baseline (HR = 1.10, p < 0.001) were independently associated with increased risk of mortality. Amnestic MCI was marginally associated with increased risk of mortality (HR = 1.93, p = 0.08) in primary analyses and significantly (p < 0.05) in several sensitivity analyses.

CONCLUSIONS

In this longitudinal, prospective study, baseline dementia resulted in a 2- to 3-times increase in risk of mortality in ET, further highlighting the clinical significance of cognitive impairment, specifically dementia, in this population.

The impact of nutritional support on malnourished inpatients with aging-related vulnerability

OBJECTIVES

Malnutrition is highly prevalent in patients with aging-related vulnerability defined by very old age (≥80 y), physical frailty or cognitive impairment, and increases the risks for morbidity and mortality. The effects of individualized nutritional support for patients with aging-related vulnerability in the acute hospital setting on mortality and other clinical outcomes remains understudied.

METHODS

For this secondary analysis of the randomized-controlled Effect of Early Nutritional Support on Frailty, Functional Outcomes, and Recovery of Malnourished Medical Inpatients Trial (EFFORT), we analyzed data of patients at a nutritional risk (Nutritional Risk Screening 2002 score ≥3 points) with aging-related vulnerability, randomized to receive protocol-guided individualized nutritional support to reach specific protein and energy goals (intervention group) or routine hospital food (control group). The primary endpoint was all-cause 30-d mortality.

RESULTS

Of the 881 patients with aging-related vulnerability, 23.4% presented with a frailty syndrome, 81.8% were age ≥80 y and 15.3% showed cognitive impairment. Patients with aging-related vulnerability receiving individualized nutritional support compared with routine hospital food showed a >50% reduction in the risk of 30-day mortality (60 of 442 [13.6%] versus 31 of 439 [7.1%]; odds ratio: 0.48; 95% confidence interval, 0.31-0.76; P = 0.002). Significant improvements were also found for long-term mortality at 180 days, as well as functional outcomes and quality of life measures.

CONCLUSIONS

Malnourished patients with aging-related vulnerability show a significant and clinically relevant reduction in the risk of mortality and other adverse clinical outcomes after individualized in-hospital nutritional support compared to routine hospital nutrition. These data support the early screening of patients with aging-related vulnerability for nutritional risk, followed by a nutritional assessment and implementation of individualized nutritional interventions.

Impact of Mild Cognitive Impairment on Mortality and Cause of Death in the Elderly

BACKGROUND

Mild cognitive impairment (MCI) is a cognitive state that lies on the continuum between normal aging and dementia, and the prevalence of MCI is higher than dementia. However, the risk for mortality of people with MCI has been far less studied than that of people with dementia, and the population attributable risk percent (PAR%) of death attributable to MCI has not been estimated yet.

OBJECTIVE

To investigate the impact of MCI on mortality and the cause of death in the elderly, and to estimate the PAR% of deaths attributable to MCI.

METHODS

Data came from 7,315 elderly subjects aged ≥60 years without dementia from two cohort studies with diagnostic assessments of MCI at baseline. Deaths among participants were confirmed through the nationwide mortality database of Statistics Korea.

RESULTS

MCI increased the risk of mortality in a multivariate Cox proportional model adjusting for age, sex, education, smoking, alcohol drinking, chronic illness, depression, vascular components, and cohort (hazard ratio = 1.59, 95% confidence interval 1.30, 1.94). PAR% of death attributable to MCI was 10.7% for age 65-74 years, 16.0% for age 75-84 years, and 24.2% for age ≥85 years. In the elderly with MCI, mortality risks from cerebrovascular disease, respiratory disease, and external causes were higher than in the cognitively normal elderly.

CONCLUSIONS

Our results suggest that the mortality risk of MCI in Asian countries may be comparable to that in Western countries, and MCI can contribute to the death of the elderly as much as dementia.

Is Dementia More Fatal Than Previously Estimated? A Population-based Prospective Cohort Study

Dementia increases the risk of mortality (ROM) in the elderly and estimates of hazard ratio (HR) of dementia for mortality have ranged from 1.7 to 6.3. However, previous studies may have underestimated ROM of dementia due to length bias, which occurs when failing to include the persons with rapidly progressive diseases, who died before they could be included in the study. This population-based prospective cohort study conducted on 6,752 randomly sampled Koreans, aged 60 years or older (the Korean Longitudinal Study on Cognitive Aging and Dementia). Cognitive disorders were evaluated at baseline and 2-year follow-up using the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet (CERAD-K), and prevalent and incident cases of dementia were identified. The participants' deaths were confirmed through the National Mortality Database of Statistics Korea. We compared the ROM between prevalent and incident dementia, and estimated HR of dementia for mortality using Cox proportional hazards model. Of the 5,097 responders to the 2-year follow-up assessment, 150 participants had dementia from the baseline (prevalent dementia), and 95 participants developed dementia during the 2-year follow-up period (incident dementia). The ROM of participants with incident dementia was about 3 times higher than the ROM of those with prevalent dementia (HR = 3.04, 95% confidence interval [CI] = 1.34-6.91). Compared to cognitively normal participants at both the baseline and 2-year follow-up assessments, the ROM of those with incident dementia approximately 8 times higher (HR = 8.37, 95 % CI = 4.23-16.54). In conclusion, the ROM of dementia using prevalent cases was underestimated due to length bias, and dementia may be much more fatal than previously estimated. In clinical settings, the ROM of dementia warrants the attention of physicians, particularly in recently incident dementia cases.

Modifiable Risk Factors Discriminate Memory Trajectories in Non-Demented Aging: Precision Factors and Targets for Promoting Healthier Brain Aging and Preventing Dementia

BACKGROUND

Non-demented cognitive aging trajectories are characterized by vast level and slope differences and a spectrum of outcomes, including dementia.

OBJECTIVE

The goal of AD risk management (and its corollary, promoting healthy brain aging) is aided by two converging objectives: 1) classifying dynamic distributions of non-demented cognitive trajectories, and 2) identifying modifiable risk-elevating and risk-reducing factors that discriminate stable or normal trajectory patterns from declining or pre-impairment patterns.

METHOD

Using latent class growth analysis we classified three episodic memory aging trajectories for n = 882 older adults (baseline Mage=71.6, SD=8.9, range = 53-95, female=66%): Stable (SMA; above average level, sustained slope), Normal (NMA; average level, moderately declining slope), and Declining (DMA; below average level, substantially declining slope). Using random forest analyses, we simultaneously assessed 17 risk/protective factors from non-modifiable demographic, functional, psychological, and lifestyle domains. Within two age strata (Young-Old, Old-Old), three pairwise prediction analyses identified important discriminating factors.

RESULTS

Prediction analyses revealed that different modifiable risk predictors, both shared and unique across age strata, discriminated SMA (i.e., education, depressive symptoms, living status, body mass index, heart rate, social activity) and DMA (i.e., lifestyle activities [cognitive, self-maintenance, social], grip strength, heart rate, gait) groups.

CONCLUSION

Memory trajectory analyses produced empirical classes varying in level and slope. Prediction analyses revealed different predictors of SMA and DMA that also varied by age strata. Precision approaches for promoting healthier memory aging-and delaying memory impairment-may identify modifiable factors that constitute specific targets for intervention in the differential context of age and non-demented trajectory patterns.

Subjective Cognitive Decline Prediction of Mortality: Results from the Einstein Aging Study

BACKGROUND

The relation of pre-dementia stages to mortality has not been fully explored. Previous work examining subjective cognitive decline (SCD) and mortality is limited and mixed regarding methods used and consistency of findings.

OBJECTIVE

To examine SCD and mortality in a longitudinal, community-based cohort, using item response theory (IRT) methodology to form a composite SCD measure. Also, to assess whether this relationship was independent of clinical cognitive status.

METHODS

The Einstein Aging Study is a diverse longitudinal cohort of adults aged ≥70. SCD items were extracted from baseline CERAD questionnaires and a composite score was formed using IRT methodology. A total of 1,741 participants with complete data were clinically diagnosed as cognitively normal, or as having amnestic mild cognitive impairment (aMCI), nonamnestic mild cognitive impairment (naMCI), or dementia. 645 deaths occurred over a period of 8,912 person-years of follow-up. Cox proportional hazard models predicted time to death adjusting for covariates.

RESULTS

A one standard deviation unit increase in level of SCD was associated with >20% higher risk of mortality. However, when models were adjusted for clinical cognitive status, the association was no longer significant. Both dementia and aMCI predicted mortality. Furthermore, when analyses focused only on those without cognitive impairment, SCD level did not predict mortality.

CONCLUSIONS

The association of SCD with mortality may be due to the association of SCD with clinical cognitive status. Thus, SCD may be used as a community-based screen to initially identify those with cognitive impairment who may be at greatest risk for death.

Risk Factors for Mild Cognitive Impairment, Dementia and Mortality: The Sydney Memory and Ageing Study

BACKGROUND

The nature and commonality of late-life risk factors for mild cognitive impairment (MCI), dementia, and mortality remain unclear. Our aim was to investigate potential risk factors, simultaneously in a single cohort including many individuals initially with normal cognition and followed for 6 years.

METHODS

We classified 873 community-dwelling individuals (70-90 years old and without dementia at baseline) from the Sydney Memory and Ageing Study as cognitively normal (CN), having MCI or dementia, or deceased 6 years after baseline. Associations with baseline demographic, lifestyle, health, and medical factors were investigated, including apolipoprotein (APOE) genotype, MCI at baseline, and reversion from MCI to CN within 2 years of baseline.

RESULTS

Eighty-three (9.5%) participants developed dementia and 114 (13%) died within 6 years; nearly 33% had MCI at baseline, of whom 28% reverted to CN within 2 years. A core set of baseline factors was associated with MCI and dementia at 6 years, including older age (per year: odds ratios and 95% confidence intervals = 1.08, 1.01-1.14 for MCI; 1.19, 1.09-1.31 for dementia), MCI at baseline (5.75, 3.49-9.49; 8.23, 3.93-17.22), poorer smelling ability (per extra test point: 0.89, 0.79-1.02; 0.80, 0.68-0.94), slower walking speed (per second: 1.12, 1.00-1.25; 1.21, 1.05-1.39), and being an APOE ε4 carrier (1.84, 1.07-3.14; 3.63, 1.68-7.82). All except APOE genotype were also associated with mortality (age: 1.11, 1.03-1.20; MCI: 3.87, 1.97-7.59; smelling ability: 0.83, 0.70-0.97; walking speed: 1.18, 1.03-1.34). Compared with stable CN participants, individuals reverting from MCI to CN after 2 years were at greater risk of future MCI (3.06, 1.63-5.72). Those who reverted exhibited some different associations between baseline risk factors and 6-year outcomes than individuals with stable MCI.

CONCLUSION

A core group of late-life risk factors indicative of physical and mental frailty are associated with each of dementia, MCI, and mortality after 6 years. Tests for slower walking speed and poorer smelling ability may help screen for cognitive decline. Individuals with normal cognition are at greater risk of future cognitive impairment if they have a history of MCI.

Mortality in Incident Cognitive Impairment: Results of the Prospective AgeCoDe Study

OBJECTIVES

To investigate mortality risk and survival time in new-incident cases of cognitive impairment (CI) in old age.

DESIGN

Prospective cohort study in six German cities.

SETTING

German Study on Ageing, Cognition, and Dementia in Primary Care Patients (AgeCoDe).

PARTICIPANTS

Two thousand eighty-nine nondemented GP patients aged 75+.

MEASUREMENTS

Every 18 months, trained psychologists and physicians conducted structured clinical interviews at the participants' homes. Dates of death were obtained from relatives, general practitioner (GP), or the local registry offices. We used the Kaplan-Meier survival method to estimate survival times of individuals with and without incident CI and multivariable Cox proportional hazards regressions to assess the association between CI and mortality risk, controlled for covariates.

RESULTS

Out of the 2,089 included patients at follow-up I, 859 (41.1%) died during the subsequent mean observation period of 8.0 years. Patients with incident CI at follow-up I showed a significantly higher case-fatality rate per 1,000 person-years (74.2, 95% CI = 64.2-84.2 vs 47.8, 95% CI = 44.6-51.0) and a significantly shorter mean survival time in the observation period than those without (7.8 vs 9.1 years; P < .001). The association between incident CI and mortality remained significant in the multivariable Cox analyses-incident CI was associated with a 42% increased, incident severe CI with a 75% increased mortality risk.

CONCLUSION

Our findings suggest an elevated mortality risk in newly acquired cognitive deficits in old age. Even though further studies are required to analyze potential underlying mechanisms, our findings support the notion that such cognitive deficits should be taken seriously in clinical practice not only for an increased risk of developing dementia but also for a broader range of possible adverse health outcomes.

Dementia-associated mortality and its predictors among older adults in sub-Saharan Africa: results from a 2-year follow-up in Congo (the EPIDEMCA-FU study)

BACKGROUND

between 2011 and 2012, we carried out a study of dementia prevalence in central Africa throughout the EPIDEMCA (Epidemiology of Dementia in Central Africa) programme.

OBJECTIVE

to assess dementia-related mortality among Congolese older people from the EPIDEMCA study after 2 years of follow-up.

DESIGN

longitudinal population-based cohort study.

SETTING

Gamboma and Brazzaville, Republic of Congo.

METHODS

older participants were traced and interviewed in rural and urban Congo annually between 2012 and 2014. DSM-IV and NINCDS-ADRDA criteria were required for dementia diagnosis. Data on vital status were collected throughout the follow-up. Cox proportional hazards model was used to assess the link between baseline dementia diagnosis and mortality risk.

RESULTS

of 1,029 participants at baseline, 910 (88.4%) have a complete cognitive diagnosis. There were 791 participants (76.87%) with normal cognition, 56 (5.44%) with MCI and 63 (6.12%) with dementia. After 2 years of follow-up, 101 (9.8%) participants had died. Compared with participants with normal cognition, patients with dementia had 2.5 times higher mortality risk (HR = 2.53, 95% CI 1.42-4.49, P = 0.001). Among those with dementia, only clinical severity of dementia was associated with an additional increased mortality risk (HR = 1.91; CI 95%, 1.23-2.96; P = 0.004). Age (per 5-year increase), male sex and living in an urban area were independently associated with increased mortality risk across the full cohort.

CONCLUSION

among Congolese older adults, dementia is associated with increased mortality risk. Our results highlight the need for targeted health policies and strategies for dementia care in sub-Saharan Africa (SSA).

Mortality in mild cognitive impairment varies by subtype, sex, and lifestyle factors: the Mayo Clinic Study of Aging

BACKGROUND

Etiologic differences in mild cognitive impairment (MCI) subtypes may impact mortality.

OBJECTIVE

To assess the rate of death in MCI overall, and by subtype, in the population-based Mayo Clinic Study of Aging.

METHODS

Participants aged 70-89 years at enrollment were clinically evaluated at baseline and 15-month intervals to assess diagnoses of MCI and dementia. Mortality in MCI cases versus cognitively normal (CN) individuals was estimated using Cox proportional hazards models.

RESULTS

Over a median follow-up of 5.8 years, 331 of 862 (38.4%) MCI cases and 224 of 1,292 (17.3%) cognitively normal participants died. Compared to CN individuals, mortality was elevated in persons with MCI (hazard ratio [HR] = 1.79; 95% CI: 1.41 to 2.27), and was higher for non-amnestic MCI (naMCI; HR = 2.40; 95% CI: 1.72 to 3.36) than for amnestic MCI (aMCI; HR = 1.61; 95% CI: 1.25 to 2.09) after adjusting for confounders. Mortality varied significantly by sex, education, history of heart disease, and engaging in moderate physical exercise (p for interaction <0.05 for all). Mortality rate estimates were highest in MCI cases who were men, did not exercise, had heart disease, and had higher education versus CN without these factors, and for naMCI cases versus aMCI cases without these factors.

CONCLUSIONS

These findings suggest stronger impact of etiologic factors on naMCI mortality. Prevention of heart disease, exercise vigilance, may reduce MCI mortality and delayed MCI diagnosis in persons with higher education impacts mortality.

Global N-acetylaspartate in normal subjects, mild cognitive impairment and Alzheimer's disease patients

BACKGROUND

Mild cognitive impairment (MCI) is an intermediary state on the way to Alzheimer's disease (AD). Little is known about whole brain concentration of the neuronal marker, N-acetylaspartate (NAA) in MCI patients.

OBJECTIVE

To test the hypothesis that since MCI and AD are both neurodegenerative, quantification of the NAA in their whole brain (WBNAA) could differentiate them from cognitively-intact matched controls.

METHODS

Proton MR spectroscopy to quantify the WBNAA was applied to 197 subjects (86 females) 72.6 ± 8.4 years old (mean ± standard deviation). Of these, 102 were cognitively intact, 42 diagnosed as MCI, and 53 as probable AD. Their WBNAA amounts were converted into absolute concentration by dividing with the brain volume segmented from the MRI that also yielded the fractional brain volume (fBPV), an atrophy metric.

RESULTS

WBNAA concentration of MCI and AD patients (10.5 ± 3.0 and 10.1 ± 2.9 mM) were not significantly different (p = 0.85). They were, however, highly significantly 25-29% lower than the 14.1 ± 2.4 mM of normal matched controls (p < 10-4). The fBPV of MCI and AD patients (72.9 ± 4.9 and 69.9 ± 4.7%) differed significantly from each other (4%, p = 0.02) and both were significantly lower than the 74.6 ± 4.4% of normal elderly (2%, p = 0.003 for MCI; 6%, p < 10-4 for AD). ROC curve analysis has shown WBNAA to have 70.5% sensitivity and 84.3% specificity to differentiate MCI or AD patients from normal elderly versus just 68.4 and 65.7% for fBPV.

CONCLUSION

Low WBNAA in MCI patients compared with cognitively normal contemporaries may indicate early neuronal damage accumulation and supports the notion of MCI as an early stage of AD. It also suggests WBNAA as a potential marker of early AD pathology.

Cognitive impairment, all-cause and cause-specific mortality among non-demented older adults

BACKGROUND

cognitive impairment is widespread among older adults even in the absence of dementia, but very little is known about the association between cognitive impairment not due or not yet converted to dementia and mortality. The association between cognitive impairment and mortality contributes to assessing cognitive impairment-related risk constellation in old age in the absence of manifest dementia.

OBJECTIVE

to assess the impact of cognitive impairment on all-cause and cause-specific mortality among non-demented older adults and to explore the nature of the association between cognitive impairment and mortality.

DESIGN

an observational cohort study (ESTHER study; 2000-present).

SETTING

German state of Saarland.

SUBJECTS

a subsample of 1,622 participants aged ≥70 with measurement of cognitive function through the Cognitive Telephone Screening Instrument (COGTEL) and exclusion of a possible dementia diagnosis at both COGTEL baseline (2005-08) and over the mortality follow-up (2005-13).

RESULTS

during an average follow-up of 6.1 years, 231 participants (14.2%) died. Participants with low COGTEL total scores had ∼60% increased mortality compared with participants with higher COGTEL total scores in Cox regression models adjusting for a wide range of possible confounders (hazard ratio = 1.62; confidence interval 1.13-2.33). Dose-response analyses with restricted cubic splines indicate a monotonic inverse relationship between cognitive function and mortality.

CONCLUSION

cognitive impairment in the absence of manifest dementia is an important independent predictor of mortality, especially among men. The administration of cognitive tests among older adults may provide relevant information for patient care and treatment decisions.

SOURCES OF FUNDING

financial sponsors played no role in the design, execution, analysis and interpretation of data.

Mortality rates and predictors in community-dwelling elderly individuals with cognitive impairment: an eight-year follow-up after initial assessment

BACKGROUND

We assessed eight-year mortality rates and predictors in a rural cohort of elderly individuals with cognitive impairment.

METHODS

A total of 1,035 individuals, including 155 (15.0%) individuals with cognitive impairment, no dementia (CIND), and 69 (6.7%) individuals with clinically diagnosed dementia were followed for eight years from 1997. The initial assessment involved a two-step diagnostic procedure performed during a door-to-door survey, and mortality data were obtained from the Korean National Statistical Office (KNSO). The relationship between clinical diagnosis and risk of death was examined using the Cox proportional hazards model after adjusting for age, sex, and education.

RESULTS

During follow-up, 392 individuals died (37.9%). Compared to persons without cognitive impairment, mortality risk was nearly double among those with CIND (hazard ratio [95% confidence interval], 1.92 [1.46-2.54]), and this increased more than three-fold among those with dementia (3.20 [2.30-4.44]). Old age and high scores on the behavioral changes scale at diagnosis were two common predictors of mortality among those with CIND and dementia. Among the items on the behavioral changes scale, low sociability, less spontaneity, and poor hygiene were associated with increased mortality in individuals with CIND. Conversely, low sociability, excessive emotionality, and irritability were associated with increased mortality in patients with dementia.

CONCLUSIONS

Both dementia and CIND increased mortality risk compared with normal cognition in this community cohort. It is important to identify and manage early behavioral changes to reduce mortality in individuals with CIND and dementia.

Cause of death in mild cognitive impairment: a prospective study (NEDICES)

BACKGROUND AND PURPOSE

Previous studies have reported the occurrence of increased mortality rates among individuals with mild cognitive impairment (MCI), but possible links between MCI subtypes and cause-specific mortality need to be explored. To examine short-term mortality (5 years), long-term mortality (13 years) and cause-specific mortality of individuals over 65 years of age suffering from MCI compared with cognitively unimpaired individuals in the Neurological Disorders in Central Spain (NEDICES) cohort.

METHODS

Mild cognitive impairment was classified using standardized psychometric and functional assessment in accordance with diagnostic convention. Cox's proportional hazards models, adjusted by sociodemographics and comorbidity factors, were used to assess the risk of death at 5 and 13 years of MCI subtypes compared with a reference group of older people without cognitive impairment (N = 2329). Causes of death were obtained from the National Population Register of Spain.

RESULTS

There were 1484 deceased individuals at 13 years. MCI subtypes were defined as amnestic single domain (N = 259), amnestic multiple domain (N = 197) and non-amnestic (N = 641). After adjusting for covariates, only the amnestic multiple domain MCI subtype showed an increased hazard ratio (HR) for mortality at 5 years versus the reference group. However, the HR for mortality at 13 years was increased for all MCI subtypes. The HR by MCI subtype was 1.19 in the non-amnestic subtype (95% CI 1.05-1.36), 1.31 in the amnestic single domain subtype (95% CI 1.10-1.56) and 1.67 in the amnestic multiple domain subtype (95% CI 1.38-2.02). In terms of cause-specific mortality, the chance of death from dementia was statistically higher in all MCI subtypes.

CONCLUSION

Amnestic multiple domain MCI showed the greatest risk of mortality in comparison with other MCI subtypes at different intervals. Dementia was the only cause-specific mortality that was increased in MCI individuals.

Caring for older adults with mild cognitive impairment: an update for nurses

Mild cognitive impairment (MCI) is a mild decline in single or multiple cognitive domains, while global cognition and basic activities of daily living remain intact. Nurses play an important role in early detection of MCI and providing care to maintain maximum independence for individuals with MCI. This article seeks to provide nurses with a review of the most recent research regarding the etiology and diagnosis of MCI, related risk and protective factors, patient and family experiences, and current interventions. This update provides research evidence to inform nursing practice of MCI care.

Dietary patterns are associated with cognition among older people with mild cognitive impairment

There has been increasing interest in the influence of diet on cognition in the elderly. This study examined the cross-sectional association between dietary patterns and cognition in a sample of 249 people aged 65–90 years with mild cognitive impairment (MCI). Two dietary patterns; whole and processed food; were identified using factor analysis from a 107-item; self-completed Food Frequency Questionnaire. Logistic regression analyses showed that participants in the highest tertile of the processed food pattern score were more likely to have poorer cognitive functioning; in the lowest tertile of executive function (OR 2.55; 95% CI: 1.08–6.03); as assessed by the Cambridge Cognitive Examination. In a group of older people with MCI; a diet high in processed foods was associated with some level of cognitive impairment.

Incidence of mild cognitive impairment in the Pittsburgh Cardiovascular Health Study-Cognition Study

OBJECTIVES AND METHODS

The purpose of this study was to examine the incidence of mild cognitive impairment (MCI) and patterns of progression from incident MCI to dementia in 285 cognitively normal subjects (mean age, 78.9 years) in the Cardiovascular Health Study-Cognition Study from 1998-1999 to 2010-2011.

RESULTS

Two hundred (70%) of the participants progressed to MCI; the age-adjusted incidence of MCI was 111.09 (95% confidence interval, 88.13-142.95) per 1,000 person-years. A total of 107 (53.5%) of the incident MCI subjects progressed to dementia. The mean time from MCI to dementia was 2.8 ± 1.8 years. Forty (20%) of the incident MCI cases had an "unstable" course: 19 (9.5%) converted to MCI and later returned to normal; 10 (5%) converted to MCI, to normal, and later back to MCI; 7 (3.5%) converted to MCI, to normal, to MCI, and later to dementia; and 4 (2%) converted to MCI, to normal, and later to dementia. There was an increased mortality rate among the cognitively normal group (110.10 per 1,000 person-years) compared to those with incident MCI who converted to dementia (41.32 per 1,000 person-years).

CONCLUSIONS

The majority of the subjects aged >80 years developed an MCI syndrome, and half of them progressed to dementia. Once the MCI syndrome was present, the symptoms of dementia appeared within 2 to 3 years. Progression from normal to MCI or from normal to MCI to dementia is not always linear; subjects who developed MCI and later returned to normal can subsequently progress to dementia. Competing mortality and morbidity influence the study of incident MCI and dementia in population cohorts.

Behavioral symptoms in community-dwelling elderly Nigerians with dementia, mild cognitive impairment, and normal cognition

BACKGROUND

Few studies have examined the neuropsychiatric status of patients with dementia and cognitive impairment in the developing world despite the fact that current demographic trends suggest an urgent need for such studies.

OBJECTIVE

To assess the level of neuropsychiatric symptoms in community-dwelling individuals with dementia, cognitive impairment no dementia and normal cognition.

METHODS

Subjects were from the Ibadan site of Indianapolis-Ibadan Dementia Project with stable diagnoses of normal cognition, cognitive impairment, no dementia/mild cognitive impairment (CIND/MCI), and dementia. Informants of subjects made ratings on the neuropsychiatric inventory and blessed dementia scale; subjects were tested with the mini mental state examination.

RESULTS

One hundred and eight subjects were included in the analytic sample, 21 were cognitively normal, 34 were demented, and 53 were CIND/MCI. The diagnostic groups did not differ in age, per cent female, or per cent with any formal education. The most frequent symptoms among subjects with CIND/MCI were depression (45.3%), apathy (37.7%), night time behavior (28.3%), appetite change (24.5%), irritability (22.6%), delusions (22.6%), anxiety (18.9%), and agitation (17.0%). Depression was significantly more frequent among the CIND/MCI and dementia (44.1%) groups compared with the normal cognition group (9.5%). Distress scores were highest for the dementia group, lowest for the normal cognition group, and intermediate for the CIND/MCI group.

CONCLUSION

Significant neuropsychiatric symptomatology and distress are present among cognitively impaired persons in this community-based study of older adults in this sub-Saharan African country. Programs to assist family members of cognitively impaired and demented persons should be created or adapted for use in developing countries.

Survival in a large elderly population of patients with dementia and other forms of psychogeriatric diseases

BACKGROUND

Dementia and other psychogeriatric diseases in elderly patients bring an increased risk of death. Better knowledge of prognosis in elderly patients affected by dementia or mental illness should be of great importance in order to improve care plans and assist in medical decisions.

METHODS

We have investigated the survival time in 2,112 patients with dementia and other forms of psychogeriatric diseases, enrolled during 1990 to 2005 and followed up until 2009, and the influence of diagnoses, plasma homocysteine level, presence of vascular disease and renal impairment.

RESULTS

The survival time after diagnosis in most diagnostic groups is about a third compared to an average population of similar age and sex. Age was the main predictor of survival time in all patients.

CONCLUSIONS

All diagnoses, except in patients with subjective cognitive impairments, showed an increased mortality. These estimates can be used for prognosis and planning for patients, carers, service providers and policy makers.

Population-based distribution and psychometric properties of a short cognitive performance measure in the population-based Heinz Nixdorf Recall Study

BACKGROUND

Providing a valid and sensitive measure of different domains of cognitive performance in epidemiologic studies of early old-age populations presents a methodological challenge, given the broad range of variability in cognitive functioning in this age group.

OBJECTIVES

(1) To provide data on the distribution of cognitive performance scores in a representative sample of an early old-age population, and (2) to assess psychometric properties of a short cognitive performance measure developed within the framework of a cohort study.

DESIGN

Population-based cohort study.

SETTING AND PARTICIPANTS

As part of the second examination of the Heinz Nixdorf Recall Study, 4,145 participants aged 50-80 years underwent a short cognitive performance assessment composed of 5 subtests with a mean duration of 7.31 min. Additionally, a subsample of 656 participants had a detailed neuropsychological and neurological examination.

METHODS

Age- and education-specific cognitive performance scores in the total sample were calculated. Based on data from the subsample, concurrent validity was examined by comparing findings with a clinically validated neuropsychological assessment.

RESULTS

In the total sample, younger and more highly educated participants had higher scores of cognitive performance. In the subsample, a good accuracy [area under the curve (AUC) = 0.81 (0.74-0.87)] of the short cognitive performance assessment compared with results from a clinically established Alzheimer disease assessment scale and diagnosis of mild cognitive impairment [AUC = 0.82 (0.78-0.82)] was observed.

CONCLUSION

This brief, cognitive performance measure, documenting good psychometric properties, can be useful in future epidemiological investigations exploring different domains and overall cognitive functioning in early old-age populations.

Incidence and risk factors for cognitive impairment no dementia and mild cognitive impairment in African Americans

The aim of this study was to estimate the age-specific incidence of cognitive impairment, no dementia and mild cognitive impairment (CIND/MCI) in a large, community-based sample of older African Americans in Indianapolis, IN. A longitudinal, prospective, 2-stage design was used with follow-up assessments 2 and 5 years after the baseline. A total of 1668 participants completed the 2-year follow-up and a total of 1255 participants completed the 5-year follow-up. The person-years method was used to calculate incidence rates. The age-standardized, annual incidence of CIND/MCI was 4.95% (CI=3.39-6.52) and the subtype of medically unexplained memory loss (single-domain and multidomain amnestic MCI) was 3.67% (CI 2.75-4.48). Rates increased with age (3.43% for participants aged 65 to 74 y, 6.44% from age 75 to 84 y, and 9.62% from age 85+ y), history of head injury [OR 2.37 (CI 1.31-4.29)], and history of depression [OR 2.22 (CI 1.16-4.25)] while increased years of schooling was protective [OR 0.91 (CI 0.85-0.97)]. Rates did not vary substantially by sex. Almost 1 in 20 elderly community-dwelling African Americans, and almost 1 in 10 of the oldest-old (85+ y) developed CIND/MCI each year in this cohort. Risk factors of age and education suggest exposures or mechanisms at both ends of the life span may be important variables in onset of CIND/MCI.

Mild cognitive impairment: incidence and risk factors: results of the leipzig longitudinal study of the aged

OBJECTIVES

To provide information on age- and sex-specific incidence rates of mild cognitive impairment (MCI) and risk factors for incident MCI.

DESIGN

Prospective longitudinal cohort.

SETTING

Leipzig Longitudinal Study of the Aged, a population-based German study of the epidemiology of dementia and mild cognitive impairment.

PARTICIPANTS

At baseline, 1,692 subjects aged 75 and older were included in the sample.

MEASUREMENTS

Trained psychologists and physicians conducted structured clinical interviews including neuropsychological assessment and questions about sociodemographics, familial history of dementia, activities of daily living, subjective memory impairment, and lifestyle (alcohol consumption, smoking) at participants' homes. Structured third-party interviews were conducted with proxies. Incidence was calculated according to the person-years-at-risk method. Cox proportional hazards models were used to examine the association between risk factors and incident MCI.

RESULTS

During an 8-year follow-up period, 26.4% (n=137) of the 519 study participants (population at risk) were identified as incident MCI cases (person-years=1,791.1). The overall incidence rate of MCI was 76.5 (95% confidence interval=64.7-90.4) per 1,000 person-years. Older age, subjective memory impairment, impairment in instrumental activities of daily living, and antecedent lower cognitive performance were found to be significantly associated with the development of future MCI.

CONCLUSION

MCI is highly incident in the elderly population. For the purpose of early detection of dementia, subjective memory impairment should be taken seriously as a possible prestage of MCI.

Factors affecting survival of patients with neurodegenerative disease

BACKGROUND

Survival varies widely among different neurodegenerative diseases. Data on the role of the Mini Mental State Examination (MMSE) and apolipoprotein E (APOE) in survival are sparse except for Alzheimer's disease (AD).

METHODS

We studied mortality of 3,581 patients in an academic clinic from 1993 to 2004. Average follow-up was 4.1 years. We studied patients with amyotrophic lateral sclerosis (ALS) (n = 174), possible AD (n = 206), probable AD (n = 1,175), Parkinson's disease (PD) (n = 661), mild cognitive impairment (MCI) (n = 357), frontotemporal dementia (FTD) (n = 94), Lewy body disease (LBD) (n = 64), and controls (n = 850). We compared patients' mortality to the US population and to controls.

RESULTS

Mortality ranged from 7% for controls to 58% for ALS patients. The median survival times from initial visit for PD, FTD, probable AD, possible AD, LBD, and ALS were 8.9, 7.0, 5.9, 5.6, 5.3, and 2.7 years, respectively. Mortality rate ratios comparing each disease to controls were 39.43, 7.25, 3.70, 3.51, 2.47, 2.73, and 1.61 for ALS, FTD, LBD, PD, probable AD, possible AD, and MCI, respectively. A lower initial MMSE score was associated with higher mortality for probable AD, PD, and MCI, while APOE4 predicted mortality for PD and LBD. Non-whites had 20% lower mortality rates than whites for all dementias combined, adjusting for education.

CONCLUSIONS

All neurologic diseases, including MCI, had increased mortality versus controls. A lower MMSE score and APOE4 presence predicted higher mortality for some patient groups.

The effect of maintaining cognition on risk of disability and death

OBJECTIVES

To determine whether long-term maintenance of cognition is associated with health advantages such as lower mortality or incident disability in older adults.

DESIGN

Longitudinal cohort study.

SETTING

Community clinics at two sites.

PARTICIPANTS

Two thousand seven hundred thirty-three adults with a mean age of 74 at baseline and 80 at follow-up.

MEASUREMENTS

Cognitive function was assessed using the Modified Mini-Mental State Examination (3MS), a test of global cognition, at least two times. Three cognitive groups were defined based on 4-year participant-specific slopes (maintainers, slopes of >or=0; minor decliners, slopes <0 but no more than 1 standard deviation (SD) below the mean; major decliners, slopes >1 SD below the mean). Whether the cognitive groups differed in mortality and incident disability during the subsequent 3 years was determined.

RESULTS

Nine hundred eighty-four (36%) participants were maintainers, 1,314 (48%) were minor decliners, and 435 (16%) were major decliners. Maintainers had lower mortality (7% vs 14%, hazard ratio (HR)=0.48, 95% confidence interval (CI)=0.36-0.63) and incident disability (22% vs 29%, HR=0.74, 95% CI=0.62-0.89) than minor decliners. After adjustment for age, race, sex, education, apolipoprotein E epsilon4, depression, body mass index, stroke, hypertension, and diabetes mellitus, these differences remained. As expected, major decliners had greater mortality (20%) and incident disability (40%) than minor decliners.

CONCLUSION

A substantial proportion of older adults maintain cognitive function in their eighth and ninth decades of life. These older adults demonstrate lower risk of death and functional decline than those with minor cognitive decline, supporting the concept of "successful" cognitive aging.

[Mild cognitive impairment]

Mild cognitive impairment (MCI) is a syndrome that spans the area between normal ageing and dementia. It is classified into amnestic and non-amnestic types, both with two subtypes: single domain and multiple domains. Prevalence of MCI depends on criteria and population and can vary from 0.1 to 42% persons of older age. In contrast to dementia, cognitive deterioration is less severe and activities of daily living are preserved. Most impaired higher cognitive functions in MCI are memory, executive functions, language, visuospatial functions, attention etc. Also there are depression, apathy or psychomotor agitation, and signs of psychosis. Aetiology of MCI is multiple, mostly neurodegenerative, vascular, psychiatric, internistic, neurological, traumatic and iatrogenic. Persons with amnestic MCI are at a higher risk of converting to Alzheimer's disease, while those with a single non-memory domain are at risk of developing frontotemporal dementia. Some MCI patients also progress to other dementia types, vascular among others. In contrast, some patients have a stationary course, some improve, while others even normalize. Every suspicion of MCI warrants a detailed clinical exploration to discover underlying aetiology, laboratory analyses, neuroimaging methods and some cases require a detailed neuropsychological assessment. At the present time there is no efficacious therapy for cognitive decline in MCI or the one that could postpone conversion to dementia. The treatment of curable causes, application of preventive measures and risk factor control are reasonable measures in the absence of specific therapy.

Differences in brain volume, hippocampal volume, cerebrovascular risk factors, and apolipoprotein E4 among mild cognitive impairment subtypes

OBJECTIVES

To evaluate demographics, magnetic resonance imaging (MRI) measures, and vascular risk among mild cognitive impairment (MCI) subtypes.

DESIGN

Cross-sectional study.

SETTING

Both clinics and the community.

PARTICIPANTS

A total of 153 subjects with MCI, 218 cognitively normal older individuals (controls), and 68 patients with Alzheimer disease.

MAIN OUTCOME MEASURES

Classification of subjects with MCI according to current subtype diagnostic convention based on neuropsychological performance, estimates of vascular risk based on medical history, research MRI unless there was a specific contraindication, and apolipoprotein E genotype.

RESULTS

Of the 153 subjects with MCI, 65 were diagnosed with amnestic single-domain, 46 with amnestic multiple-domain, 27 with nonamnestic single-domain, and 15 with nonamnestic multiple-domain MCI. Analyses of control, MCI, and Alzheimer disease cases revealed significant differences in brain and hippocampal volumes between each group. Post hoc analyses of MRI measures among the MCI subtypes found that patients with amnestic single-domain MCI had significantly less brain atrophy and that hippocampal volume differed significantly from controls for the 2 amnestic forms of MCI. Apolipoprotein E genotype prevalence was significantly greater in the amnestic and nonamnestic subtypes of MCI. Conversely, the nonamnestic subtypes were more likely to have increased vascular risk and to be African American.

CONCLUSIONS

Amnestic forms of MCI appear to have demographic, genetic, and MRI findings suggestive of Alzheimer disease pathology, whereas the nonamnestic forms of MCI have findings suggestive of vascular disease. Importantly, however, all subjects with MCI showed evidence of brain injury, and the biological differences among subtypes are relatively subtle beyond the memory vs nonmemory groupings.

Biracial population study of mortality in mild cognitive impairment and Alzheimer disease

OBJECTIVE

To assess mortality associated with mild cognitive impairment (MCI) and Alzheimer disease (AD) among older African Americans and whites from an urban community.

DESIGN

Longitudinal population-based observational study.

SETTING

Four adjacent neighborhoods in Chicago, Illinois.

PARTICIPANTS

Persons deemed free of dementia in a previous wave of data collection (n = 1715) underwent detailed clinical evaluation: 802 had no cognitive impairment (46.8%), 597 had MCI (34.8%), 296 had AD (17.3%), and 20 had other forms of dementia (1.2%).

MAIN OUTCOME MEASURE

All-cause mortality.

RESULTS

During as many as 10 years of observation (mean [SD], 4.7 [3.0] years), 634 individuals died (37.0%). Compared with people without cognitive impairment, risk of death was increased by about 50% among those with MCI (hazard ratio [95% confidence interval], 1.48 [1.22-1.80]) and was nearly 3-fold greater among those with AD (2.84 [2.29-3.52]). These effects were seen among African Americans and whites and did not differ by race. Among participants with MCI, risk of death increased with more severe cognitive impairment, and this effect did not vary by race. A similar effect was seen among participants with AD, but it was slightly stronger for African Americans vs whites. In the MCI and AD groups, the association of cognitive impairment with survival was stronger for perceptual speed than for other cognitive functions.

CONCLUSION

The presence and severity of MCI and AD are associated with reduced survival among African Americans, and these effects are comparable to those seen among whites.