White matter lesions are related to impaired instrumental activities of daily living poststroke

Association of Alzheimer's Disease and Other Neuropathologies With Functional Disability in Persons With and Without Dementia

BACKGROUND

Dementia results from multiple neuropathologies causing cognitive impairment sufficiently severe to affect functional status. However, these pathologies and functional impairment are common in persons without dementia. We examined the association of Alzheimer's disease (AD) and multiple other neuropathologies with instrumental and basic activities of daily living in persons with and without dementia.

METHODS

Participants were 1 509 deceased from the Religious Orders Study or Rush Memory and Aging Project. Pathologic AD and 3 other AD indices were examined, in addition to 4 non-AD neurodegenerative pathologies: cerebral amyloid angiopathy (CAA), hippocampal sclerosis, TDP-43, and Lewy bodies, and 4 cerebrovascular pathologies: gross- and microinfarctions, athero- and arteriolosclerosis. Functional assessment included Lawton and Katz Index Instrumental and Basic Activities of Daily Living (IADL and BADL). Ordinal regression models adjusted for age, sex, and education were used to examine the association of neuropathologies with IADL and BADL.

RESULTS

Alzheimer's disease and the other neuropathologies were associated with impaired IADL (all ps < .001) and with impaired BADL (ps < .01), except for atherosclerosis and CAA, which were not associated with BADL. The effects of most neuropathologies were largely affected by dementia. However, small effects on IADL remained for PHF-tau tangles after adjusting models for dementia. Direct effects of gross infarcts on IADL and BADL and of microinfarcts on BADL remained unchanged after adjusting the models for dementia.

CONCLUSIONS

Alzheimer's disease and all other neuropathologies are strongly associated with functional disability. The association of most neuropathologies with disability was eliminated or attenuated by dementia, except for gross infarcts and microinfarcts.

Association Between Small Vessel Disease and Financial Capacity: A Study Based on Cognitively Normal Older Adults

Background

Financial capacity is vital for the elderly, who possess a substantial share of global wealth but are vulnerable to financial fraud.

Objective

We explored the link between small vessel disease (SVD) and financial capacity in cognitively unimpaired (CU) older adults via both cross-sectional and longitudinal analyses.

Methods

414 CU participants underwent MRI and completed the Financial Capacity Instrument-Short Form (FCI-SF). Subsequent longitudinal FCI-SF data were obtained from 104, 240, and 141 participants at one, two, and four years, respectively. SVD imaging markers, encompassing white matter hyperintensities (WMH), cerebral microbleeds (CMB), and lacune were evaluated. We used linear regression analyses to cross-sectionally explore the association between FCI-SF and SVD severity, and linear mixed models to assess how baseline SVD severity impacted longitudinal FCI-SF change. The false discovery rate method was used to adjust multiple comparisons.

Results

Cross-sectional analysis revealed a significant association between baseline WMH and Bank Statement (BANK, β=-0.194), as well as between lacune number and Financial Conceptual Knowledge (FC, β= -0.171). These associations were stronger in APOE ɛ4 carriers, with β= -0.282 for WMH and BANK, and β= -0.366 for lacune number and FC. Longitudinally, higher baseline SVD total score was associated with severe FCI-SF total score decrease (β= -0.335). Additionally, baseline WMH burden predicted future decreases in Single Checkbook/Register Task (SNG, β= -0.137) and FC (β= -0.052). Notably, the association between baseline WMH and SNG changes was amplified in APOE ɛ4 carriers (β= -0.187).

Conclusions

Severe SVD was associated with worse FCI-SF and could predict the decline of financial capacity in CU older adults.

Relationship between preoperative neutrophil-to-lymphocyte ratio and postoperative delirium: The PNDABLE and the PNDRFAP cohort studies

OBJECTIVES

In this study, the relationship between preoperative neutrophil-to-lymphocyte ratio (NLR) and Alzheimer-related biomarkers in cerebrospinal fluid (CSF) was investigated to determine whether high NLR is a potential risk factor for postoperative delirium (POD) and to evaluate its predictive efficacy.

METHODS

We selected 1000 patients from the perioperative neurocognitive disorder risk factor and prognosis (PNDRFAP) database and 999 patients from the perioperative neurocognitive disorder and biomarker lifestyle (PNDABLE) database. Patients in the PNDABLE database have been measured for Alzheimer-related biomarkers in CSF (Aβ40 , Aβ42 , P-tau, and tau protein). Mini-mental state examination was used to assess the preoperative mental status of patients. POD was diagnosed using the confusion assessment method and assessed for severity using the memorial delirium assessment scale. Logistic regression analysis was utilized to explore the association of preoperative NLR with POD. What's more, we also performed sensitivity analysis by adding corrected confounders, and the results were almost unchanged. Spearman's rank correlation was used to determine the associations between NLR and Alzheimer-related biomarkers. Mediation analyses with 10,000 bootstrapped iterations were used to explore the mediation effects. Finally, we use decision curves and the nomogram model to evaluate the efficacy of preoperative NLR in predicting POD; we also performed external validation using data from Qilu Hospital.

RESULT

Logistic regression results showed that an elevated preoperative NLR was a risk factor for the development of POD in patients (PNDRFAP: OR = 1.067, 95% CI 1.020-1.116; PNDABLE: OR = 1.182, 95% CI 1.048-1.335, p < .05). Spearman's rank correlation analysis showed a positive but weak correlation between NLR and P-tau/T-tau (R = .065). The mediating effect results indicate that NLR likely mediates the occurrence of POD through elevated tau protein levels (proportion: 47.47%). The results of the box plots showed statistically significant NLR and CSF biomarkers between the POD and non-POD (NPOD) groups (p < .05), with higher NLR, P-tau, and T-tau in the POD group than in the NPOD group. In contrast, the NPOD group had higher Aβ42 levels compared to the POD group. In addition, we used R package to plot the decision curve and nomogram both suggesting a good predictive effect of preoperative NLR on the occurrence of POD.

CONCLUSION

Elevated preoperative NLR levels may be a risk factor for POD and likely mediate the development of POD through elevated P-tau/T-tau levels.

MRI factors associated with cognitive functioning after acute onset brain injury: Systematic review and meta-analysis

Impairments of memory, attention, and executive functioning are frequently reported after acute onset brain injury. MRI markers hold potential to contribute to identification of patients at risk for cognitive impairments and clarification of mechanisms. The aim of this systematic review was to summarize and value the evidence on MRI markers of memory, attention, and executive functioning after acute onset brain injury. We included ninety-eight studies, on six classes of MRI factors (location and severity of damage (n = 15), volume/atrophy (n = 36), signs of small vessel disease (n = 15), diffusion-weighted imaging measures (n = 36), resting-state functional MRI measures (n = 13), and arterial spin labeling measures (n = 1)). Three measures showed consistent results regarding their association with cognition. Smaller hippocampal volume was associated with worse memory in fourteen studies (pooled correlation 0.58 [95% CI: 0.46-0.68] for whole, 0.11 [95% CI: 0.04-0.19] for left, and 0.34 [95% CI: 0.17-0.49] for right hippocampus). Lower fractional anisotropy in cingulum and fornix was associated with worse memory in six and five studies (pooled correlation 0.20 [95% CI: 0.08-0.32] and 0.29 [95% CI: 0.20-0.37], respectively). Lower functional connectivity within the default-mode network was associated with worse cognition in four studies. In conclusion, hippocampal volume, fractional anisotropy in cingulum and fornix, and functional connectivity within the default-mode network showed consistent associations with cognitive performance in all types of acute onset brain injury. External validation and cut off values for predicting cognitive impairments are needed for clinical implementation.

A High Neutrophil-to-Lymphocyte Ratio Predicts Higher Risk of Poststroke Cognitive Impairment: Development and Validation of a Clinical Prediction Model

Objective

Poststroke cognitive impairment (PSCI) is a serious complication of stroke. The neutrophil-to-lymphocyte ratio (NLR) is a marker of peripheral inflammation. The relationship between the NLR and PSCI is far from well studied, and the thesis of this study was to assess the predictive value of the NLR in patients with PSCI, and establish and verify the corresponding prediction model based on this relationship.

Methods

A total of 367 stroke patients were included in this study. Neutrophils, lymphocytes, and NLRs were measured at baseline, and clinical and neuropsychological assessments were conducted 3 months after stroke. The National Institutes of Health Scale (NIHSS) was used to assess the severity of stroke. A Chinese version of the Mini Mental State Examination (MMSE) was used for the assessment of cognitive function.

Results

After three months of follow-up, 87 (23.7%) patients were diagnosed with PSCI. The NLR was significantly higher in PSCI patients than in non-PSCI patients (P &lt; 0.001). Patient age, sex, body mass index, NIHSS scores, and high-density lipoprotein levels also differed in the univariate analysis. In the logistic regression analysis, the NLR was an independent risk factor associated with the patients with PSCI after adjustment for potential confounders (OR = 1.67, 95%CI: 1.21–2.29, P = 0.002). The nomogram based on patient sex, age, NIHSS score, and NLR had good predictive power with an AUC of 0.807. In the validation group, the AUC was 0.816.

Conclusion

An increased NLR at admission is associated with PSCI, and the model built with NLR as one of the predictors can increase prognostic information for the early detection of PSCI.

Instrumental Activities of Daily Living: The Processes Involved in and Performance of These Activities by Japanese Community-Dwelling Older Adults with Subjective Memory Complaints

Subjective memory complaints (SMCs) may predict the onset of dementia. The purpose of this study was to clarify characteristics of performance of activities of daily living (ADL) for older adults with SMCs and to offer support options that enable them to maintain their community-based lifestyle. A self-administered questionnaire was sent to 2000 randomly selected members of CO-OP Kagoshima, and 621 responded. 270 responders answered all questions were categorized into SMC (+) group and SMC (−) group (n = 133). Participants were evaluated the Process Analysis of Daily Activity for Dementia. A 2-sample t-test or the Chi-square test were used to compare the averages of continuous variables or the proportions of categorical variables. The results showed the SMC (+) group ranked significantly lower in ability to use the telephone, shop, cook, do housekeeping, manage finances, and manage medications compared with the SMC (−) group. In addition, the SMC (+) group was significantly less independent than the SMC (−) group in many processes requiring the use of tools, operation of machines, management of goods, selection of tools, and monitoring. To enable continued independence of older adults’ experiencing SMCs, it may be important to analyze their performance of ADL and to develop plans for supporting their strengths.

Subcortical Ischemic Change as a Predictor of Driving Cessation in the Elderly

OBJECTIVE

Motor, perceptual, and cognitive functions are known to affect driving competence. Subcortical ischemic changes on brain magnetic resonance imaging (MRI) can reflect reduction in cognitive and motor performance. However, few studies have reported the relationship between subcortical ischemic changes and driving competence of the elderly. Thus, the objective of this study was to investigate the association between subcortical ischemic changes on MRI and driving abilities of the elderly.

METHODS

Participants (n=540) were drawn from a nationwide, multicenter, hospital-based, longitudinal cohort. Each participant underwent MRI scan and interview for driving capacity categorized into 'now driving' and 'driving cessation (driven before, not driving now)'. Participants were divided into three groups (mild, n=389; moderate, n=116; and severe, n=35) depending on the degree of white matter hyperintensity (WMH) on MRI at baseline. Driving status was evaluated at follow-up. Statistical analyses were conducted using χ2 test, analysis of variance (ANOVA), structured equation model (SEM), and generalized estimating equation (GEE).

RESULTS

In SEM, greater baseline degree of WMH was directly associated with driving cessation regardless of cognitive or motor dysfunction (β=-0.110, p<0.001). In GEE models after controlling for age, sex, education, cognitive, and motor dysfunction, more severe change in the degree of WMH was associated with faster change from 'now driving' state to 'driving cessation' state over time in the elderly (β=-0.508, p<0.001).

CONCLUSION

In both cross-sectional and longitudinal results, the degree of subcortical ischemic change on MRI might predict driving cessation in the elderly.

Biological and imaging predictors of cognitive impairment after stroke: a systematic review

BACKGROUND

Cognitive impairment is frequent after stroke, and several studies have suggested that biological and imaging characteristics present before stroke are associated with the development of post-stroke cognitive impairment.

OBJECTIVE

The aim of our study was to systematically review biological and imaging predictors of cognitive impairment after stroke.

METHOD

Studies were identified from bibliographic databases and reference lists, and were included if conducted in patients with acute stroke, with at least 30 patients, and a follow-up of at least 3 months. We included articles on potential biomarkers of cognitive impairment that pre-existed to stroke.

RESULTS

We identified 22,169 articles, including 20,349 with abstract. After analysis, 66 studies conducted in 42 cohorts met selection criteria. They included 30-9522 patients [median 170; interquartile range (IQR) 104-251] with a median follow-up of 12 months (IQR 3-36). All studies met quality criteria for description of the study population and standardization of biomarkers. Twenty-nine studies met all quality criteria. There was no convincing evidence that any biological marker may predict cognitive impairment. The most consistent predictors of cognitive impairment after stroke were global atrophy and medial temporal lobe atrophy.

CONCLUSION

Pre-existing cerebral atrophy is the most consistent predictor of cognitive impairment that can be identified in patients with an acute stroke.

Association Between Subclinical Brain Infarcts and Functional Decline Trajectories

OBJECTIVES

To test associations between subclinical brain infarcts (SBIs) and functional decline independently of intervening clinical vascular events and other vascular risk factors.

DESIGN

Longitudinal follow-up for a mean 7.3 years. Generalized estimating equation models were used to test associations between SBIs, number of perivascular spaces (PVSs), baseline Barthel Index (BI), and change in BI, adjusting for sociodemographic, vascular, and cognitive risk factors and for stroke and myocardial infarction occurring during follow-up.

SETTING

Population-based prospective cohort study.

PARTICIPANTS

Stroke-free individuals from the racially and ethnically diverse Northern Manhattan Study (N=1,290).

MEASUREMENTS

Annual functional assessments using the BI (range 0-100).

RESULTS

Mean age was 70.6 ± 9.0, 40% of participants were male, 66% were Hispanic, 193 (16%) had SBIs, and 508 (42%) had large PVSs. SBIs were not associated with baseline BI. In a fully adjusted model, there was a change in BI of -0.85 points per year (95% confidence interval (CI)=-1.01 to -0.69); those with SBI had an additional change in BI 0f -0.88 points (95% CI=-1.43 to -0.32). There were no associations between PVS and baseline BI or change in BI.

CONCLUSION

In a large population-based study, we found a strong and independent association between "subclinical" markers of cerebrovascular injury and important clinical, person-centered functional trajectories. Future research could clarify the evolution of such subclinical markers over time and test strategies to prevent their progression and minimize related disability. J Am Geriatr Soc 66:2144-2150, 2018.

Cerebral white matter disease and functional decline in older adults from the Northern Manhattan Study: A longitudinal cohort study

BACKGROUND

Cerebral white matter hyperintensities (WMHs) on MRI are common and associated with vascular and functional outcomes. However, the relationship between WMHs and longitudinal trajectories of functional status is not well characterized. We hypothesized that whole brain WMHs are associated with functional decline independently of intervening clinical vascular events and other vascular risk factors.

METHODS AND FINDINGS

In the Northern Manhattan Study (NOMAS), a population-based racially/ethnically diverse prospective cohort study, 1,290 stroke-free individuals underwent brain MRI and were followed afterwards for a mean 7.3 years with annual functional assessments using the Barthel index (BI) (range 0-100) and vascular event surveillance. Whole brain white matter hyperintensity volume (WMHV) (as percentage of total cranial volume [TCV]) was standardized and treated continuously. Generalized estimating equation (GEE) models tested associations between whole brain WMHV and baseline BI and change in BI, adjusting for sociodemographic, vascular, and cognitive risk factors, as well as stroke and myocardial infarction (MI) occurring during follow-up. Mean age was 70.6 (standard deviation [SD] 9.0) years, 40% of participants were male, 66% Hispanic; mean whole brain WMHV was 0.68% (SD 0.84). In fully adjusted models, annual functional change was -1.04 BI points (-1.20, -0.88), with -0.74 additional points annually per SD whole brain WMHV increase from the mean (-0.99, -0.49). Whole brain WMHV was not associated with baseline BI, and results were similar for mobility and non-mobility BI domains and among those with baseline BI 95-100. A limitation of the study is the possibility of a healthy survivor bias, which would likely have underestimated the associations we found.

CONCLUSIONS

In this large population-based study, greater whole brain WMHV was associated with steeper annual decline in functional status over the long term, independently of risk factors, vascular events, and baseline functional status. Subclinical brain ischemic changes may be an independent marker of long-term functional decline.

Periventricular White Matter Hyperintensities and Functional Decline

BACKGROUND/OBJECTIVES

We previously showed that global brain white matter hyperintensity volume (WMHV) was associated with accelerated long-term functional decline. The objective of the current study was to determine whether WMHV in particular brain regions is more predictive of functional decline.

DESIGN

Prospective population-based study.

SETTING

Northern Manhattan magnetic resonance imaging (MRI) study.

PARTICIPANTS

Individuals free of stroke at baseline (N = 1,195; mean age 71 ± 9; n = 460 (39%) male).

MEASUREMENTS

Participants had brain MRI with axial T1, T2, and fluid attenuated inversion recovery sequences. Volumetric WMHV distribution across 14 brain regions (brainstem; cerebellum; bilateral frontal, occipital, temporal, and parietal lobes; and bilateral anterior and posterior periventricular white matter (PVWM)) was determined using a combination of bimodal image intensity distribution and atlas-based methods. Participants had annual functional assessments using the Barthel Index (BI) (range 0-100) over a mean of 7.3 years and were followed for stroke, myocardial infarction (MI), and mortality. Because there were multiple collinear variables, least absolute shrinkage and selection operator (LASSO) regression-selected regional WMHV variables most associated with outcomes and adjusted generalized estimating equations models were used to estimate associations with baseline BI and change over time.

RESULTS

Using LASSO regularization, only right anterior PVWM was found to meet criteria for selection, and each standard deviation greater WMHV was associated with accelerated functional decline of 0.95 additional BI points per year (95% confidence interval (CI) = -1.20 to -0.70) in an unadjusted model, -0.92 points per year (95% CI = -1.18 to -0.67) with baseline covariate adjustment, and -0.87 points per year (95% CI = -1.12 to -0.62) after adjusting for incident stroke and MI.

CONCLUSION

In this large population-based study with long-term repeated measures of function, periventricular WMHV was particularly associated with accelerated functional decline.

Differential Effect of Left vs. Right White Matter Hyperintensity Burden on Functional Decline: The Northern Manhattan Study

Asymmetry of brain dysfunction may disrupt brain network efficiency. We hypothesized that greater left-right white matter hyperintensity volume (WMHV) asymmetry was associated with functional trajectories. Methods: In the Northern Manhattan Study, participants underwent brain MRI with axial T1, T2, and fluid attenuated inversion recovery sequences, with baseline interview and examination. Volumetric WMHV distribution across 14 brain regions was determined separately by combining bimodal image intensity distribution and atlas based methods. Participants had annual functional assessments with the Barthel index (BI, range 0-100) over a mean of 7.3 years. Generalized estimating equations (GEE) models estimated associations of regional WMHV and regional left-right asymmetry with baseline BI and change over time, adjusted for baseline medical risk factors, sociodemographics, and cognition, and stroke and myocardial infarction during follow-up. Results: Among 1,195 participants, greater WMHV asymmetry in the parietal lobes (-8.46 BI points per unit greater WMHV on the right compared to left, 95% CI -3.07, -13.86) and temporal lobes (-2.48 BI points, 95% CI -1.04, -3.93) was associated with lower overall function. Greater WMHV asymmetry in the parietal lobes (-1.09 additional BI points per year per unit greater WMHV on the left compared to right, 95% CI -1.89, -0.28) was independently associated with accelerated functional decline. Conclusions: In this large population-based study with long-term repeated measures of function, greater regional WMHV asymmetry was associated with lower function and functional decline. In addition to global WMHV, WHMV asymmetry may be an important predictor of long-term functional status.

The Use of Visual Rating Scales to Quantify Brain MRI Lesions in Patients with HIV Infection

BACKGROUND AND PURPOSE

Human immunodeficiency virus (HIV)-infected patients commonly have abnormalities in cerebral white matter that are visible on magnetic resonance imaging (MRI) as hyperintensities (WMHs). Visual rating scales (VRSs) have been used to quantify WMH in other diseases such as cerebral small vessel disease (CSVD), but not in HIV. Such scales are advantageous because they are applicable to routinely acquired MRIs and so are suitable for large-scale studies and clinical care. We sought to establish the utility of three VRSs (the Fazekas, Scheltens, and van Sweiten scales) in HIV.

METHODS

The Manhattan HIV Brain Bank (MHBB) is a longitudinal cohort study that performs serial neurologic examinations and neuropsychological testing. All brain MRIs (n = 73) performed for clinical purposes on MHBB participants were scored using the three VRSs. We assessed reliability, validity, and correlation of the VRS with clinical factors relevant to HIV and CSVD.

RESULTS

The VRSs all showed acceptable internal consistency and interrater reliability and were highly correlated with one another (r = 0.836-0.916, P < .001). The Fazekas and Scheltens scales demonstrated more WMH in periventricular regions, and the Scheltens scale also suggested a frontal to occipital gradient, with greater WMH frontally. All three VRSs correlated significantly with cognitive impairment (global T score). Age and hepatitis C virus antibody serostatus were the strongest clinical/demographic correlates of WMH, followed by African-American race.

CONCLUSIONS

VRSs reliably quantify WMH in HIV-infected individuals and correlate with cognitive impairment. Future studies may find routinely acquired brain MRI quantified by VRS to be an accessible and meaningful neurologic outcome measure in HIV.

Significance of Cerebral Small-Vessel Disease in Acute Intracerebral Hemorrhage

BACKGROUND AND PURPOSE

The significance of structural changes associated with cerebral small-vessel disease (SVD), including white matter lesions (WML), lacunes, and brain atrophy, to outcome from acute intracerebral hemorrhage is uncertain. We determined associations of computed tomographic radiological manifestations of cerebral SVD and outcomes, and in terms of any differential effect of early intensive blood pressure-lowering treatment, in the large-scale Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial (INTERACT2).

METHODS

We graded WML (van Swieten scale), the presence of lacunes, and brain atrophy (2 linear measurements and visual rating) for 2069 of 2839 patients with available baseline brain computed tomography (<6 hours of intracerebral hemorrhage onset) by 3 independent neurologists blind to clinical data.

RESULTS

WML grade and 2 linear measurements of brain atrophy were associated with death or major disability at 90 days: multivariable-adjusted odds ratios for WML (grade 3 and 4 versus 0), frontal ratio, and third ventricle Sylvian fissure distance (most versus least severe atrophy quartile) were 1.42 (95% confidence interval, 1.02-1.98), 1.47 (1.08-1.99), and 1.64 (1.21-2.22), respectively (all P for trend <0.05). There was no association between lacunes and outcomes. There were no significant differences in the effects of intensive blood pressure-lowering across subgroups of cerebral SVD.

CONCLUSIONS

Preexisting cerebral SVD manifestations of WML and brain atrophy predict poor outcome in acute intracerebral hemorrhage. There is no apparent hazard of early intensive lowering of blood pressure according to the INTERACT2 protocol, in patients with underlying cerebral SVD.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00716079.

Ideal Cardiovascular Health Metrics Are Associated with Disability Independently of Vascular Conditions

Background

Vascular risk factors may be associated with disability independently of vascular events. We examined whether the American Heart Association’s 7 ideal cardiovascular health (CVH) metrics were independently associated with disability in a nationally representative cohort.

Methods

Adults age ≥20 years from the National Health and Nutrition Examination Survey 2005–2012 were included. Ideal CVH was calculated as a composite of 7 measures, each scored 0–2. Primary predictors were number of ideal CVH metrics and score of CVH metrics. The outcome was a dichotomous score from 20 activities of daily living (ADL) and instrumental ADLs. Unadjusted and adjusted weighted logistic models estimated associations between ideal CVH and disability. The data were analyzed in 2015.

Results

Among 22692 participants, mean age was 46.9 years. Cardiac disease and stroke were present in 6.6% and 2.8%; 90.3% had poor physical activity and 89.9% poor diet. Among 3975 individuals with full CVH data, in fully adjusted models, OR for disability was 0.90 (95% CI 0.83–0.98) per point increase in ideal CVH score, and 0.84 (0.73–0.97) per additional number of ideal CVH metrics.

Conclusions

CVH metrics were strongly and significantly associated with reduced odds of disability independently of vascular and non-vascular conditions. Poorer CVH may cause subclinical vascular disease resulting in disability.

The Combined Effect of Neuropsychological and Neuropathological Deficits on Instrumental Activities of Daily Living in Older Adults: a Systematic Review

To date, studies have consistently demonstrated associations between either neuropsychological deficits or neuroanatomical changes and instrumental activities of daily living (IADL) in aging. Only a limited number of studies have evaluated morphological brain changes and neuropsychological test performance concurrently in relation to IADL in this population. As a result, it remains largely unknown whether these factors independently predict functional outcome. The current systematic review intended to address this lack of information by reviewing the literature on older adults, incorporating studies that examined e.g., normal aging, but also stroke or dementia patients. A comprehensive search of databases (Pubmed, Embase, Medline, Web of Science, PsycINFO) and reference lists was performed, focusing on papers in the English language that examined the combined effect of neuropsychological and neuroanatomical factors on IADL in samples of adults with an average age above 50. In total, 58 potential articles were identified; 20 were included in the review. The results show that especially neuropsychological variables (primarily memory and executive functions) independently predict IADL. Although some unique predictive value of brain morphological changes, such as hippocampal atrophy, was found, support for the importance of white matter changes was limited. However, the results of the studies reviewed are diverse, and appear to be at least partially determined by the variables included. For example, studies were less likely to find an independent effect of cognition if they solely employed a cognitive screening instrument. This indicates that a structured examination of neuroanatomical and neuropsychological correlates of IADL in different patient populations is warranted.

Ideal cardiovascular health predicts functional status independently of vascular events: the Northern Manhattan Study

BACKGROUND

We hypothesized that the American Heart Association's metric of ideal cardiovascular health (CVH) predicts improved long-term functional status after adjusting for incident stroke and myocardial infarction.

METHODS AND RESULTS

In the prospective, multiethnic Northern Manhattan Study, stroke-free individuals in northern Manhattan aged ≥40 years had annual assessments of the primary outcome of functional status with the Barthel index (BI), for a median of 13 years. Ideal CVH was calculated as a composite of 7 measures, each scored on a scale of 0 to 2. Primary predictors were (1) number of ideal CVH metrics, and (2) total score of all CVH metrics. Of 3219 participants, mean age was 69 years (SD 10), 63% were female, 21% were white, 25% were non-Hispanic black, and 54% were Hispanic. Twenty percent had 0 to 1 ideal CVH metrics, 32% had 2, 30% had 3, 14% had 4, and 4% had 5 to 7. Both number of ideal CVH categories and higher CVH metric scores were associated with higher mean BI scores at 5 and 10 years. 0047 Gradients persisted when results were adjusted for incident stroke and myocardial infarction, when mobility and nonmobility domains of the BI were analyzed separately, and when BI was analyzed dichotomously. At 10 years, in a fully adjusted model, differences in mean BI score were lower for poor versus ideal physical activity (3.48 points, P<0.0001) and fasting glucose (4.58 points, P<0.0001).

CONCLUSIONS

Ideal CVH predicts functional status, even after accounting for incident vascular events. Vascular functional impairment is an important outcome that can be reduced by optimizing vascular health.

Association between subjective memory complaints and impaired higher-level functional capacity in people aged 60 years or older

OBJECTIVE

We aimed to investigate the association between subjective memory complaints and higher-level functional capacity in either people with long-term care needs or those who require help to maintain functional capacity.

METHODS

We conducted a cross-sectional study among participants aged 60 years or older. We measured subjective memory complaints, higher-level functional capacity, and depressive symptoms, and then estimated odds ratios (ORs) by multiple logistic analysis. Subjective memory complaints were used as the predictor variable, higher-level functional capacity as the outcome variable, and age, depressive symptoms, medical history of diabetes and hypertension, frequency of going out, falling within a year, and body mass index as possible confounders. We assessed higher-level functional capacity using the Tokyo Metropolitan Institute of Gerontology (TMIG) index of competence score ≤5 as a cut-off (which is associated with higher one-year mortality rates).

RESULTS

We conducted analyses using 501 people aged 60 years or older. Among women, subjective memory complaints were associated with impaired higher-level functional capacity after adjustment for age and depressive symptoms (OR=3.36; 95% confidence interval [CI], 1.59-7.08). Among the men, subjective memory complaints were not significantly associated with impaired higher-level functional capacity after adjustment for age and depressive symptoms (OR=1.91; 95% CI, 0.88-4.12).

CONCLUSIONS

Subjective memory complaints among women can indicate impaired higher-level functional capacity and may suggest higher one-year mortality rates.

The relationship of leukoaraiosis and the clinical severity of vascular Parkinsonism

Vascular Parkinsonism (VP) is referred to as secondary Parkinsonian syndrome. It occurs with lacunar state or sub-cortical white matter micro-angiopathy and is highly associated with vascular risk factors and leukoaraiosis, also known as cerebral white matter lesions (WML). This study aimed to assess the prevalence of different vascular risk factors and WML in patients with VP, and their impact on clinical features. Sixty-two consecutive VP patients (70.2 ± 9.2 years) were evaluated for clinical severity using the Unified Parkinson's Disease Rating Scale (UPDRS). WML was assessed and scored on fluid-attenuated inversion recovery T2-weighted (FLAIR) magnetic resonance imaging (MRI). Cerebro-vascular risk factors, WML severity, and the UPDRS for clinical disability were analyzed statistically. There were no associations between WML score and age, sex, hypertension, diabetes, previous stroke, cardiac disease, cigarette smoking, or serum levels of cholesterol and triglyceride. The WML score positively correlated with UPDRS part I (p = 0.035) and part III (p = 0.041) scores. After adjustments for age, gender, stroke history, and use of levodopa, the WML score was associated with the UPDRS total (p = 0.020), part I (p = 0.012), part II (p = 0.039), and part III (p = 0.019) scores. The severity of WML is not associated with conventional vascular risk factors in VP patients but is significantly correlated with the UPDRS total and all sub-scores, which suggests that disruption of the cortico-sub-cortical circuits may lead to impaired mentation, behavior and mood, activities of daily living, and motor performance in these patients.

Network measures predict neuropsychological outcome after brain injury

Hubs are network components that hold positions of high importance for network function. Previous research has identified hubs in human brain networks derived from neuroimaging data; however, there is little consensus on the localization of such hubs. Moreover, direct evidence regarding the role of various proposed hubs in network function (e.g., cognition) is scarce. Regions of the default mode network (DMN) have been frequently identified as "cortical hubs" of brain networks. On theoretical grounds, we have argued against some of the methods used to identify these hubs and have advocated alternative approaches that identify different regions of cortex as hubs. Our framework predicts that our proposed hub locations may play influential roles in multiple aspects of cognition, and, in contrast, that hubs identified via other methods (including salient regions in the DMN) might not exert such broad influence. Here we used a neuropsychological approach to directly test these predictions by studying long-term cognitive and behavioral outcomes in 30 patients, 19 with focal lesions to six "target" hubs identified by our approaches (high system density and participation coefficient) and 11 with focal lesions to two "control" hubs (high degree centrality). In support of our predictions, we found that damage to target locations produced severe and widespread cognitive deficits, whereas damage to control locations produced more circumscribed deficits. These findings support our interpretation of how neuroimaging-derived network measures relate to cognition and augment classic neuroanatomically based predictions about cognitive and behavioral outcomes after focal brain injury.

Cognitive impairments associated with medial temporal atrophy and white matter hyperintensities: an MRI study in memory clinic patients

In this retrospective study, we investigated the independent effects of white matter hyperintensities (WMH) and hippocampal atrophy on cognitive functions in a broad sample of patients seen in a memory clinic. To ensure generalizability, these associations were examined irrespective of diagnosis and with minimal exclusion criteria. Next to these independent effects, interactions between WMH and hippocampal atrophy were examined. Between January 2006 and September 2011 a total of 500 patients visited the memory clinic, 397 of whom were included. Magnetic resonance images of 397 patients were visually analyzed for WMH, medial temporal atrophy (MTA), and global atrophy. We evaluated the association of WMH and MTA with the following cognitive domains: global cognition, episodic memory, working memory, executive function and psychomotor speed. Main effects and interaction effects were examined by means of correlation and regression analyses. In the regression analyses, we controlled for potential confounding effects of global atrophy. The correlational results revealed that WMH were associated with global cognition, executive function and psychomotor speed, whereas a trend was found for episodic memory. MTA was associated with all these four cognitive domains; an additional trend was observed for working memory. Hierarchical regression analyses revealed main independent effects of MTA for episodic memory, executive function, psychomotor speed and global cognition; WMH were only associated with global cognition. The interaction between MTA and WMH was significant for episodic memory only. This study demonstrates that predominantly MTA is an independent predictor not only for memory function, with which is it classically associated, but also for global cognition and executive function. Taken together, MTA may be an important correlate of cognitive deficits found in people attending the memory clinic.

Diabetes predicts long-term disability in an elderly urban cohort: the Northern Manhattan Study

PURPOSE

There are limited data on vascular predictors of long-term disability in Hispanics. We hypothesized that (1) functional status declines over time and (2) vascular risk factors predict functional decline.

METHODS

The Northern Manhattan Study contains a population-based study of 3298 stroke-free individuals aged 40 years or older, followed for median 11 years. The Barthel Index (BI) was assessed annually. Generalized estimating equations and Cox models were adjusted for demographic, medical, and social risk factors. Stroke and myocardial infarction occurring during follow-up were censored in sensitivity analysis. Secondarily, motor and nonmotor domains of the BI were analyzed.

RESULTS

Mean age (standard deviation) of the cohort (n = 3298) was 69.2 (10) years, 37% were male, 52% Hispanic, 22% diabetic, and 74% hypertensive. There was a mean annual decline of 1.02 BI points (P < .0001). Predictors of decline in BI included age, female sex, diabetes, depression, and normocholesterolemia. Results did not change with censoring. We found similar predictors of BI for motor and nonmotor domains.

CONCLUSION

In this large, population-based, multiethnic study with long-term follow-up, we found a 1% mean decline in function per year that did not change when vascular events were censored. Diabetes predicted functional decline in the absence of clinical vascular events.

Trajectory of functional decline before and after ischemic stroke: the Northern Manhattan Study

BACKGROUND AND PURPOSE

Previous research in our cohort showed a delayed decline in functional status after first ischemic stroke. We compared the long-term trajectory of functional status before and after ischemic stroke.

METHODS

The Northern Manhattan Study contains a prospective, population-based study of stroke-free individuals age ≥40 years, followed for a median of 11 years. The Barthel index (BI), a commonly used measure of activities of daily living, was assessed annually. Generalized estimating equations were used to assess functional decline over time before stroke and beginning 6 months after stroke. Follow-up was censored at the time of recurrent stroke.

RESULTS

Among 3298 participants, 210 participants had an ischemic stroke during follow-up and had poststroke BI assessed. Mean age (±SD) was 77±9 years, 38% were men, 52% were Hispanic, 37% had diabetes, and 31% had coronary artery disease. There was no difference in rate of functional decline over time before and after stroke (P=0.51), with a decline of 0.96 BI points per year before stroke (P<0.0001) and 1.24 BI points after stroke (P=0.001). However, when stratified by insurance status, among those with Medicaid or no insurance, in a fully adjusted model, there was a difference in slope before and after stroke (P=0.04), with a decline of 0.58 BI points per year before stroke (P=0.02) and 1.94 BI points after stroke (P=0.001).

CONCLUSIONS

In this large, prospective, population-based study with long-term follow-up, there was a significantly steeper decline in functional status after ischemic stroke compared with before stroke among those with Medicaid or no insurance, after adjusting for confounders.

Correlation between instrumental activities of daily living and white matter hyperintensities in amnestic mild cognitive impairment: results of a cross-sectional study

Although some studies have supported the association between white matter hyperintensities (WMH) and cognitive impairment, whether WMH are associated with the impairments in instrumental activities of daily living (IADLs) remains unknown. This cross-sectional study investigated differences in basic ADLs and IADLs among different severity of WMH in a large, well-defined registry of patients with amnestic mild cognitive impairment (aMCI). 1,514 patients with aMCI were divided into three groups according to the degree of WMH (1,026 mild, 393 moderate, and 95 severe). We compared the total IADL scores and analyzed the prevalence of the impairment for each IADL item for each group. The severity of WMH was associated with the impairments in IADLs. Among 15 Seoul IADL items, "using public transportation", "going out (short distance)", "grooming" and "participating in leisure activities/hobbies" showed greater positive association with the severity of WMH. WMH in patients with aMCI were associated with the impairments in IADLs but not in basic ADLs. These findings are likely to be more obvious with respect to using public transportation, going out (short distances), shopping, grooming and participating in leisure activities/hobbies.

The perception of meaningfulness and performance of instrumental activities of daily living from the perspectives of the medically at-risk older adults and their caregivers

The purpose of the study was to understand the impact of chronic disability on the functional ability of older adults. Thirty older adult participants and their caregivers were asked to identify which instrumental activities of daily living (IADL) are most meaningful and how their disability affected performance. Data collected through individual analysis indicated that the most important IADL tasks were driving and managing medication. Both older adult participants and their caregivers similarly perceived the health condition as significantly affecting the performance of all of the IADLs. However, there was a difference in the perception of the prior level of functioning for managing medication (z = 2.45, p = .024) and phone use (z = 2.26, p = .014). Results arrived at, and to be discussed, were in agreement with previous research findings indicating that complex tasks of daily living, particularly driving, are significant to the older adult's quality of life.

Heterogeneity in age-related white matter changes

White matter changes occur endemically in routine magnetic resonance imaging (MRI) scans of elderly persons. MRI appearance and histopathological correlates of white matter changes are heterogeneous. Smooth periventricular hyperintensities, including caps around the ventricular horns, periventricular lining and halos are likely to be of non-vascular origin. They relate to a disruption of the ependymal lining with subependymal widening of the extracellular space and have to be differentiated from subcortical and deep white matter abnormalities. For the latter a distinction needs to be made between punctate, early confluent and confluent types. Although punctate white matter lesions often represent widened perivascular spaces without substantial ischemic tissue damage, early confluent and confluent lesions correspond to incomplete ischemic destruction. Punctate abnormalities on MRI show a low tendency for progression, while early confluent and confluent changes progress rapidly. The causative and modifying pathways involved in the occurrence of sporadic age-related white matter changes are still incompletely understood, but recent microarray and genome-wide association approaches increased the notion of pathways that might be considered as targets for therapeutic intervention. The majority of differentially regulated transcripts in white matter lesions encode genes associated with immune function, cell cycle, proteolysis, and ion transport. Genome-wide association studies identified six SNPs mapping to a locus on chromosome 17q25 to be related to white matter lesion load in the general population. We also report first and preliminary data that demonstrate apolipoprotein E (ApoE) immunoreactivity in white matter lesions and support epidemiological findings indicating that ApoE is another factor possibly related to white matter lesion occurrence. Further insights come from modern MRI techniques, such as diffusion tensor and magnetization transfer imaging, as they provide tools for the characterization of normal-appearing brain tissue beyond what can be expected from standard MRI scans. There is a need for additional pre- and postmortem studies in humans, including these new imaging techniques.