2008 Alzheimer's disease facts and figures

Clinical predictors of Alzheimer's disease-like brain atrophy in individuals with memory complaints

OBJECTIVES

The definition and assessment methods for subjective cognitive decline (SCD) vary among studies. We aimed to investigate which features or assessment methods of SCD best predict Alzheimer's disease (AD)-related structural atrophy patterns.

METHODS

We assessed 104 individuals aged 55+ with memory complaints but normal cognitive screening. Our research questions were as follows: To improve the prediction of AD related morphological changes, (1) Would the use of a standardized cognitive screening scale be beneficial? (2) Is conducting a thorough neuropsychological evaluation necessary instead of relying solely on cognitive screening tests? (3) Should we apply SCD-plus research criteria, and if so, which criterion would be the most effective? (4) Is it necessary to consider medical and psychiatric comorbidities, vitamin deficiencies, vascular burden on MRI, and family history? We utilized Freesurfer to analyze cortical thickness and regional brain volume meta-scores linked to AD or predicting its development. We employed multiple linear regression models for each variable, with morphology as the dependent variable.

RESULTS

AD-like morphology was associated with subjective complaints in males, individuals with advanced age, and higher education. Later age of onset for complaints, complaints specifically related to memory, excessive deep white matter vascular lesions, and using medications that have negative implications for cognitive health (according to the Beers criteria) were predictive of AD-related morphology. The subjective cognitive memory questionnaire scores were found to be a better predictor of reduced volumes than a single-question assessment. It is important to note that not all SCD-plus criteria were evaluated in this study, particularly the APOE genotype, amyloid, and tau status, due to resource limitations.

CONCLUSIONS

The detection of AD-related structural changes is impacted by demographics and assessment methods. Standardizing SCD assessment methods can enhance predictive accuracy.

Development and validation of educational multimedia to promote public health literacy about healthy cognitive aging

OBJECTIVES

Health literacy (HL) about healthy cognitive aging is essential in preventing cognitive decline and promoting cognitive well-being. It is important that one such HL module should be scientifically designed, delivered in a technically sound manner to the audience, and specific to the context. The present study thus aimed at developing and validating educational multimedia about cognitive health.

METHODS

The study followed a methodological framework and was carried out across three phases, that is, identification of themes, development and validation of educational script and design, and validation of educational multimedia. The module was scripted based on the Integrated HL framework and the recommendations made during the modified nominal group technique among the research team. Seven speech-language pathologists (SLPs), with expertise in the field of cognitive sciences, and 15 representatives of the general public validated the module using the Educational Content Validation Instrument in Health and the Patient Education Materials Assessment Tool for Audiovisual Materials questionnaire.

RESULTS

The scientific content of the educational script received satisfactory agreements among the experts (content validity index [CVI]: 0.93) and representatives of the general public (CVI: 0.86). The technical aspects of the educational multimedia were rated to have high understandability (experts: 92.8%; representatives of general public: 98.8%) and actionability (experts and representatives of general public 100%).

CONCLUSION

Overall, the developed educational multimedia scored optimally with respect to the objective, structure, relevance of the content, actionability and understandability of the multimedia. The developed module holds the potential to be used at community and national level health educational programs or awareness campaigns to enhance public knowledge and beliefs pertaining to cognitive health.

PATIENT OR PUBLIC CONTRIBUTION

SLPs with expertise in the field of cognitive science and representatives from the general public were included to validate and obtain feedback on the developed educational multimedia.

The national public health response to Alzheimer's disease and related dementias: Origins, evolution, and recommendations to improve early detection

Longstanding gaps in the detection of Alzheimer's disease and related dementias (ADRD) and biopsychosocial care call for public health action to improve population health. We aim to broaden the understanding of the iterative role state plans have played over the last 20 years in prioritizing improvements in the detection of ADRD, primary care capacity, and equity for disproportionately affected populations. Informed by national ADRD priorities, state plans convene stakeholders to identify local needs, gaps, and barriers and set the stage for development of a national public health infrastructure that can align clinical practice reform with population health goals. We propose policy and practice actions that would accelerate the collaboration between public health, community organizations, and health systems to improve ADRD detection-the point of entry into care pathways that could ultimately improve outcomes on a national scale. HIGHLIGHTS: We systematically reviewed the evolution of state/territory plans for Alzheimer's disease and related dementias (ADRD). Plan goals improved over time but lacked implementation capacity. Landmark federal legislation (2018) enabled funding for action and accountability. The Centers for Disease Control and Prevention (CDC) funds three Public Health Centers of Excellence and many local initiatives. Four new policy steps would promote sustainable ADRD population health improvement.

Advancing Diagnostic Certainty in Alzheimer's Disease: A Synthesis of the Diagnostic Process

Changes in diagnostic certainty can be evaluated by assessing the impact of a diagnostic test in driving decision making. Diagnostic tests can be appraised using validated measures of accuracy, i.e., sensitivity, specificity, and positive or negative predictive values against a known reference standard. However, other less well formalized factors affect diagnostic certainty. These inputs are under-researched and more difficult to quantify. Clinicians assess the significance of available data in the context of their expertise, pre-diagnostic confidence, and background knowledge of populations and disease. Inherent qualities of the diagnostic test and an individual clinician's interpretation of the meaning of test results will also affect the subsequent level of diagnostic certainty. These factors are only infrequently considered alongside the diagnostic accuracy of a test. In this paper, we present a model of the different processes which can affect diagnostic certainty in Alzheimer's disease (AD). This model builds upon existing understanding and provides further insights into the complexity of diagnostic certainty in AD and how we might improve this.

Evaluation of the Reitman Centre CARERS program for supporting dementia family caregivers: a pre-post intervention study

OBJECTIVES

While family caregivers (CGs) of persons with dementia are cost-effective for the health system, this form of caregiving leads to disproportionate vulnerability to physical, mental, and social adverse health consequences among CGs. The study goal was to determine the effect of the Reitman Centre CARERS program on key outcomes in family CGs of people with dementia. The Reitman Centre CARERS program is an innovative, group psychotherapeutic skills training intervention based on integrated problem-solving techniques (PST), simulation learning, and group psychotherapy designed to address each CGs' unique situation.

DESIGN

A quasi-experimental, non-randomized, pre-post evaluation, multiple groups, multisite trial.

SETTING

Multisite group intervention provided in community agencies and hospital-based locations.

PARTICIPANTS

Spousal or adult child family CGs (n = 264) living in the community and providing care to community-dwelling family members with dementia.

MEASUREMENT

CGs were assessed for depression (CES-D); stress (PSS); burden (12-item SZBI); role overload, mastery, caregiving competence, and role captivity (Perlin scales), coping (CISS - Coping Inventory for Stressful Situations), CG reactions to CR's memory and behavioral symptoms (RMBPC). Care recipients (CRs) were assessed on basic and complex activities of daily living (Katz and Lawton). Paired t-tests and Wilcoxon signed-rank test were used for statistical analysis of both the whole group and a more compromised subgroup of CGs.

RESULTS

For the group as a whole, CGs showed significant positive change on post-intervention outcome measures of stress, depression, burden, competence, role captivity, overload, mastery, coping, and reaction to memory issues. The intervention showed especially robust effect sizes (ES) in more compromised CGs. These positive outcomes emerged despite a significant measured deterioration in CRs' function.

CONCLUSION

The CARERS program may be an effective multicomponent intervention to improve the well-being, functioning, and coping skills of dementia CGs.

Aptamer-Functionalized Carbon Nanotube Field-Effect Transistor Biosensors for Alzheimer's Disease Serum Biomarker Detection

Blood-biomarker-based tests are highly important for the early clinical diagnosis of Alzheimer's disease (AD) and the treatment and care of AD patients, but the complex serum environment and extremely low abundance of AD blood protein biomarkers present challenges. Nanomaterials are promising for constructing highly sensitive transistor-based biosensors due to their small size. However, such biosensors are difficult to fabricate on a large scale and suffer from the lack of combined optimization of reproducibility and sensitivity in complex physiological fluids. In this work, field-effect transistor (FET) biosensors based on highly uniform semiconducting carbon nanotube (CNT) thin films are mass produced to achieve highly sensitive and selective detection of the AD core blood biomarkers of β-amyloid (Aβ). The combination of the mass-produced CNT FET sensors and oligonucleotide aptamers as efficient bioreceptors enables reliable and reproducible sub-femtomolar detection in full human serum for Aβ₄₂ and Aβ₄₀ peptides and has outperformed other methods reported to date. The adsorption of biological substrates to the sensor was significantly reduced by multiple blocking steps, resulting in selectivity ratios of up to 730% (Aβ₄₀) and 800% (Aβ₄₂). The aptamer-functionalized CNT FET biosensor exhibits a large dynamic range (>10⁴), rapid response time (several minutes), and low variation (<10%) and can be delivered as a low-cost and rapid clinical detection technology for the early diagnosis and mass screening of AD. This platform will help bring complex laboratory-based and expensive diagnostic tools to the point of care.

Simultaneous Inhibitory Effects of All-Trans Astaxanthin on Acetylcholinesterase and Oxidative Stress

Alzheimer´s disease is a global neurodegenerative health concern. To prevent the disease, the simultaneous inhibition of acetylcholinesterase and oxidative stress is an efficient approach. In this study, the inhibition effect of all-trans astaxanthin mainly from marine organisms on acetylcholinesterase and oxidative stress was evaluated by a chemical-based method in vitro and cell assay model. The results show that all-trans astaxanthin was a reversible competitive inhibitor and exhibited a strong inhibition effect with half inhibitory concentration (IC₅₀ value) of 8.64 μmol/L. Furthermore, all-trans astaxanthin inhibited oxidative stress through reducing malondialdehyde content and increasing the activity of superoxide dismutase as well as catalase. All-trans astaxanthin could induce the changes of the secondary structure to reduce acetylcholinesterase activity. Molecular-docking analysis reveals that all-trans astaxanthin prevented substrate from binding to acetylcholinesterase by occupying the space of the active pocket to cause the inhibition. Our finding suggests that all-trans astaxanthin might be a nutraceutical supplement for Alzheimer´s disease prevention.

Physical Exercise and Mental Health: The Routes of a Reciprocal Relation

Sport participation and exercise practice are considered to be beneficial for mental status, yielding an improved mood and better quality of life. On the other hand, good mental fitness is thought to lead to better physical status and sport performance. The key aim of this narrative review is to provide an unstructured overview on the topic with special considerations on the role of mental and physical health to summarize the evidence on their reciprocal influence. While very few papers describe the role of mental health measures in affecting physical performance, more evidence is available concerning the effect of exercise and sport in improving mental health outcomes. Furthermore, there is a consistent role of depressive and anxiety symptoms in influencing the risk of sport injury in either recreational or elite athletes. Moreover, the importance of investigating mental health issues in elite and retired athletes is highlighted. On the basis of the available literature, several biases were found to affect the provided evidence mainly because of the complexity of a proper study design in this field.

Living with the enemy: from protein-misfolding pathologies we know, to those we want to know

Conformational diseases are caused by the aggregation of misfolded proteins. The risk for such pathologies develops years before clinical symptoms appear, and is higher in people with alpha-1 antitrypsin (AAT) polymorphisms. Thousands of people with alpha-1 antitrypsin deficiency (AATD) are underdiagnosed. Enemy-aggregating proteins may reside in these underdiagnosed AATD patients for many years before a pathology for AATD fully develops. In this perspective review, we hypothesize that the AAT protein could exert a new and previously unconsidered biological effect as an endogenous metal ion chelator that plays a significant role in essential metal ion homeostasis. In this respect, AAT polymorphism may cause an imbalance of metal ions, which could be correlated with the aggregation of amylin, tau, amyloid beta, and alpha synuclein proteins in type 2 diabetes mellitus (T2DM), Alzheimer's and Parkinson's diseases, respectively.

Cardiometabolic Modification of Amyloid Beta in Alzheimer's Disease Pathology

In recent years, several studies have suggested that cardiometabolic disorders, such as diabetes, obesity, hypertension, and dyslipidemia, share strong connections with the onset of neurodegenerative disorders such as Parkinson's and Alzheimer's disease (AD). However, establishing a definitive link between medical disorders with coincident pathophysiologies is difficult due to etiological heterogeneity and underlying comorbidities. For this reason, amyloid β (Aβ), a physiological peptide derived from the sequential proteolysis of amyloid precursor protein (APP), serves as a crucial link that bridges the gap between cardiometabolic and neurodegenerative disorders. Aβ normally regulates neuronal synaptic function and repair; however, the intracellular accumulation of Aβ within the brain has been observed to play a critical role in AD pathology. A portion of Aβ is believed to originate from the brain itself and can readily cross the blood-brain barrier, while the rest resides in peripheral tissues that express APP required for Aβ generation such as the liver, pancreas, kidney, spleen, skin, and lungs. Consequently, numerous organs contribute to the body pool of total circulating Aβ, which can accumulate in the brain and facilitate neurodegeneration. Although the accumulation of Aβ corresponds with the onset of neurodegenerative disorders, the direct function of periphery born Aβ in AD pathophysiology is currently unknown. This review will highlight the contributions of individual cardiometabolic diseases including cardiovascular disease (CVD), type 2 diabetes (T2D), obesity, and non-alcoholic fatty liver disease (NAFLD) in elevating concentrations of circulating Aβ within the brain, as well as discuss the comorbid association of Aβ with AD pathology.

Formaldehyde-Crosslinked Nontoxic Aβ Monomers to Form Toxic Aβ Dimers and Aggregates: Pathogenicity and Therapeutic Perspectives

Alzheimer's disease (AD) is characterized by the presence of senile plaques in the brain. However, medicines targeting amyloid-beta (Aβ) have not achieved the expected clinical effects. This review focuses on the formation mechanism of the Aβ dimer (the basic unit of oligomers and fibrils) and its tremendous potential as a drug target. Recently, age-associated formaldehyde and Aβ-derived formaldehyde have been found to crosslink the nontoxic Aβ monomer to form the toxic dimers, oligomers and fibrils. Particularly, Aβ-induced formaldehyde accumulation and formaldehyde-promoted Aβ aggregation form a vicious cycle. Subsequently, formaldehyde initiates Aβ toxicity in both the early-and late-onset AD. These facts also explain why AD drugs targeting only Aβ do not have the desired therapeutic effects. Development of the nanoparticle-based medicines targeting both formaldehyde and Aβ dimer is a promising strategy for improving the drug efficacy by penetrating blood-brain barrier and extracellular space into the cortical neurons in AD patients.

The Persian Version of the Quick Mild Cognitive Impairment Screen (Qmci-Pr): Psychometric Properties among Middle-Aged and Older Iranian Adults

Brief cognitive screening instruments are used to identify patients presenting with cognitive symptoms that warrant further assessment. This study aimed to evaluate the reliability and validity of the Persian version of the Quick Mild Cognitive Impairment (Qmci-Pr) among middle-aged and older Iranian adults. Consecutive patients aged ≥55 years and caregivers attending with them as normal controls (NCs) were recruited from geriatric outpatient clinics and a hospital in Tehran, Iran. All patients completed the Qmci-Pr before completing an independent detailed neuropsychological assessment and staging using the Clinical Dementia Rating (CDR) Scale. NCs underwent the same assessment. In all, 92 participants with a median age of 70 years (±13) were available. Of these, 20 participants were NCs, 24 had subjective memory complaints (SMC), 24 had mild cognitive impairment (MCI), and 24 had Alzheimer's disease (AD). The Qmci-Pr had good accuracy in differentiating SMC and NC from MCI (area under the curve (AUC): 0.80 (0.69-0.91)) and in identifying cognitive impairment (MCI and mild AD) (AUC: 0.87 (0.80-0.95)) with a sensitivity of 88% and specificity of 80%, at an optimal cut-off of <53/100. The Qmci-Pr is an accurate short cognitive screening impairment for separating NC and patients with SMC from MCI and identifying cognitive impairment. Further research with larger samples and comparison with other widely used instruments such as the Montreal Cognitive Assessment is needed. Given its established brevity, the Qmci-Pr is a useful screen for Iranian adults across the spectrum of cognitive decline.

APOE Variants in an Iberian Alzheimer Cohort Detected through an Optimized Sanger Sequencing Protocol

The primary genetic risk factor for late onset Alzheimer’s disease (LOAD) is the APOE4 allele of Apolipoprotein E (APOE) gene. The three most common variants of APOE are determined by single nucleotide polymorphisms (SNPs) rs429358 and rs7412. Our aim was to estimate allele and genotype frequencies of APOE variants in an Iberian cohort, thus helping to understand differences in APOE-related LOAD risk observed across populations. We analyzed saliva or buccal swab samples from 229 LOAD patients and 89 healthy elderly controls (≥68 years old) from Northern Portugal and Castile and León region, Spain. The genotyping was performed by Sanger sequencing, optimized to overcome GC content drawbacks. Results obtained in our Iberian LOAD and control cohorts are in line with previous large meta-analyses on APOE frequencies in Caucasian populations; however, we found differences in allele frequencies between our Portuguese and Spanish subgroups of AD patients. Moreover, when comparing studies from Iberian and other Caucasian cohorts, differences in APOE2 and APOE4 frequencies and subsequent different APOE-related LOAD risks must be clarified. These results show the importance of studying genetic variation at the APOE gene in different populations (including analyses at a regional level) to increase our knowledge about its clinical significance.

Lactic acid bacteria feeding reversed the malformed eye structures and ameliorated gut microbiota profiles of Drosophila melanogaster Alzheimer's Disease model

AIMS

To utilize transgenic GMR-Aβ42 Drosophila melanogaster as a model to evaluate potential Alzheimer's disease (AD)-reversal effects via the administration of lactic acid bacteria (LAB) strains, and associations of LAB with changes in gut microbiota profiles.

METHODS AND RESULTS

Wild type flies (Oregon-R) was crossed with glass multimer reporter-GAL4 (GMR-GAL4) to produce GMR-OreR (Control), while UAS-Aβ42 (#33769) crossed with GMR-GAL4 to produce transgenic Drosophila line that expressed Aβ42 (GMR-Aβ42). Feed containing seven different LAB strains (Lactobacillus paracasei 0291, Lactobacillus helveticus 1515, Lactobacillus reuteri CDV, Lactobacillus reuteri 8513d, Lactobacillus fermentum 8312, Lactobacillus casei Y, Lactobacillus sakei Probio65) were given to GMR-Aβ42 respectively, while feed without LAB strains were given to control and transgenic GMR-Aβ42.nf Drosophila lines. The morphology of the eyes was viewed with scanning electron microscopy (SEM). The changes in gut microbiota profiles associated with LAB were analyzed using 16s high throughput sequencing. Malformation of eye structures in transgenic GMR-Aβ42 Drosophila were reversed upon the administration of LAB strains, with more prevalent effects from Lactobacillus sakei Probio65 and Lactobacillus paracasei 0291. The GMR-Aβ42.nf group showed dominance of Wolbachia in the gut, a genus that was almost absent in the normal control group (P<0.05). The administration of L. sakei Probio65 and L. paracasei 0291 reduced the abundance of Wolbachia accompanied by increased abundance of Stenotrophomonas and Acetobacter (P<0.05), resembling the microbial profile of the control group.

CONCLUSIONS

L. sakei Probio65 and L. paracasei 0291 have more prominent effects in reversing malformed eye of transgenic GMR-Aβ42 Drosophila, and reducing the abundance of Wolbachia accompanied by an increased abundance of Stenotrophomonas and Acetobacter.

SIGNIFICANCE AND IMPACT OF THE STUDY

Potentials of LAB to prevent and/or alleviate the onset and pathogenesis of neurodegenerative diseases such as AD, supporting brain health strategies along the gut-brain axis.

Vitamin B-Can it prevent cognitive decline? A systematic review and meta-analysis

BACKGROUND

Development of cognitive decline represents substantial issues in today's society, steadily gaining importance with increasing life expectancy. One potential approach to preventing cognitive decline is to lower homocysteine by administering vitamin B. In this systematic review and meta-analysis, we address this topic and investigate whether oral supplementation of vitamin B can successfully prevent cognitive decline in cognitively unimpaired individuals.

METHODS

A computerized systematic literature search was conducted using the electronic databases PubMed, Embase, and the Cochrane Library. Eligibility criteria included oral supplementation with vitamin B (B₁, B₆, folic acid, and B₁₂) and the absence of cognitive impairment. A meta-analysis was conducted with "global cognition" as the primary outcome of this review. Secondary outcomes were changes in cognitive function in other cognitive domains reported in the included studies. Risk of bias was assessed according to the Cochrane Risk of Bias tool and the GRADE approach to establish the overall certainty of the evidence.

RESULTS

The meta-analysis did not yield a significant overall effect of supplementation with vitamin B on cognitive function (Z = 0.87; p = 0.39; SMD, 0.02; 95% CI, - 0.034, 0.08). A sensitivity analysis focusing on specific risk factors did not alter this result. Some studies reported isolated significant effects of the intervention on secondary outcomes. However, these findings were outnumbered by the number of cognitive tests that did not yield significant effects.

DISCUSSION

We found no overall evidence that oral vitamin B supplementation prevented cognitive decline. The isolated significant effects that were reported could be attributed to methodological issues. The results of this review do not provide evidence that population groups with certain risk factors would profit more from the intervention than others. Our findings do not apply to forms of administration other than oral supplementation nor do they offer information regarding the treatment of cognitively impaired individuals via the administration of vitamin B.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017071692.

Synthesis of Pyridopyrazine-1,6-dione γ-Secretase Modulators via Selective 4-Methylimidazole N1-Buchwald Arylation

An efficient synthesis of pyridopyrazine-1,6-dione γ-secretase modulators (GSMs) is described. Our route features the construction of a crystalline lactone intermediate via a selective palladium-catalyzed 4-methylimidazole N¹-arylation using the Buchwald Xantphos Pd G4 precatalyst, which does not require a preactivation step. The weak inorganic base KHCO₃ was employed to minimize saponification of a particularly sensitive lactone substrate. Additional key transformations include DABAL-Me₃-mediated lactone aminolysis and a mild TBD/ethyl trifluoroacetate mediated lactam ring closure to afford a representative GSM in high yield.

Effects of porcine brain hydrolysate on impairment of cognitive learning ability in amyloid β(1-40) -infused rats

This study assessed whether administering porcine brain hydrolysate (PBH) ameliorates the impairment of spatial cognition learning ability in amyloid β (Aβ)-infused rats. PBH was prepared using organic solvents (i.e., acetone and ethanol). Enzyme hydrolysates were derived from these PBH and the sequence of the Aβ peptide for infusion was selected. The results indicated the PBH, in particular EP (porcine brain extract with ethanol and protease N), demonstrated the potentials to reduce damage of neurodegenerative disorders in vitro and in vivo. The principal findings of this study indicate that PBH has prolyl endopeptidase inhibitory activity in vitro. Moreover, administering EP to Aβ(1-40)-infused rats significantly improves their performance on reference, spatial performance, and working memory tests during water maze tasks; concurrent proportional decreases are also observed in malondialdehyde levels, acetylcholinesterase (AChE) activity, and Aβ accumulation levels in brain tissues. The PBH was suggested to ameliorate learning deficits associated with Alzheimer's disease by inhibition of lipid peroxidation in the brain of Aβ infused rat.

Early Detection of Alzheimer's Disease Based on the Patient's Creative Drawing Process: First Results with a Novel Neuropsychological Testing Method

Based on the knowledge of art therapy, we developed a new neuropsychological drawing test in order to identify individuals with mild cognitive impairment (MCI) as well as dementia patients and healthy controls (HC). By observing a variety of drawing characteristics of 92 participants with a mean age of 67.7, art therapy and dementia experts discriminate HC from MCI, early dementia of the Alzheimer-type (eDAT), and moderate dementia of the Alzheimer-type (mDAT) by the process analysis of tree drawings on a digitizing tablet. The art therapist's average categorical rating of healthy and MCI or demented individuals matched the clinical diagnosis by 88%. In a first small study, we analyzed interrater reliability, sensitivity, specificity, negative and positive predicted values of our tree drawing test (TDT) in comparison with the clock drawing test (CDT). Similar values of moderate interrater reliability were found for the TDT (0.56) as well as for the CDT (0.54). A significant high sensitivity of 0.9 within this binary impairment scale (HC versus impaired or demented) can be demonstrated. Substantial values for the specificity (0.67) could be obtained that however remain under a perfect value of the CDT (1.0). Considering 31 individuals that received the clinical diagnosis "impaired or demented" the TDT shows a higher recognition rate for the MCI group than the CDT. Furthermore in 8 of 12 borderline cases of clinical diagnosis, the outcome of the TDT diagnosis was consistent with the final clinical result.

Low 25-Hydroxyvitamin D Concentrations and Risk of Incident Cognitive Impairment in Black and White Older Adults: The Health ABC Study

Using data from the Health, Aging, and Body Composition study, we examined whether low 25-hydroxyvitamin D (25[OH]D) concentrations were associated with prevalent or incident cognitive impairment. Serum 25(OH)D concentrations were measured in 2,786 older adults and categorized as <20 ng/mL, 20 to <30 ng/mL, or ≥30 ng/mL. Cognitive impairment was defined as a score >1.5 standard deviations below race and education specific means on either digit symbol substitution test or modified mini-mental state test. Logistic regression determined the odds of cognitive impairment at baseline and year 5 by 25(OH)D category. 25(OH)D concentrations were <30 ng/mL in 57.3% of whites and 84.6% of blacks. After excluding participants with baseline cognitive impairment (n = 340), 13% of whites and 13% of blacks developed cognitive impairment by year 5. In whites, 25(OH)D concentrations <30 ng/mL were not associated with prevalent or incident cognitive impairment. Black participants with 25(OH)D concentrations <20 ng/mL had a higher odds of prevalent, but not incident cognitive impairment (OR (95% CI): 2.05 (1.08-3.91), p = 0.03) compared to participants with 25(OH)D concentrations ≥30 ng/mL. Low 25(OH)D concentrations were associated with twofold higher odds of prevalent cognitive impairment in blacks.

A blood screening test for Alzheimer's disease

INTRODUCTION

This study combined data across four independent cohorts to examine the positive and negative predictive values of an Alzheimer's disease (AD) blood test if implemented in primary care.

METHODS

Blood samples from 1329 subjects from multiple independent, multiethnic, community-based, and clinic-based cohorts were analyzed. A "locked-down" referent group of 1128 samples was generated with 201 samples randomly selected for validation purposes. Random forest analyses were used to create the AD blood screen. Positive (PPV) and negative (NPV) predictive values were calculated.

RESULTS

In detecting AD, PPV was 0.81, and NPV was 0.95 while using the full AD blood test. When detecting mild cognitive impairment, PPV and NPV were 0.74 and 0.93, respectively. Preliminary analyses were conducted to detect any "neurodegenerative disease". The full 21-protein AD blood test yielded a PPV of 0.85 and NPV of 0.94.

DISCUSSION

The present study creates the first-ever multiethnic referent sample that spans community-based and clinic-based populations for implementation of an AD blood screen.

Computational identification and analysis of neurodegenerative disease associated protein kinases in hominid genomes

Protein kinases play an important role in the incidence of neurodegenerative diseases. However their incidence in non-human primates is found to be very low. Small differences among the genomes might influence the disease susceptibilities. The present study deals with finding the genetic differences of protein kinases in humans and their three closest evolutionary partners chimpanzee, gorilla and orangutan for three neurodegenerative diseases namely, Alzheimer's, Parkinson's and Huntington's diseases. In total 47 human protein kinases associated with three neurodegenerative diseases and their orthologs from other three non-human primates were identified and analyzed for any possible susceptibility factors in humans. Multiple sequence alignment and pairwise sequence alignment revealed that, 18 human protein kinases including DYRK1A, RPS6KB1, and GRK6 contained significant indels and substitutions. Further phosphorylation site analysis revealed that eight kinases including MARK2 and LTK contained sites of phosphorylation exclusive to human genomes which could be particular candidates in determining disease susceptibility between human and non-human primates. Final pathway analysis of these eight kinases and their targets revealed that these kinases could have long range consequences in important signaling pathways which are associated with neurodegenerative diseases.

Pyridofuropyrrolo[1,2-a]pyrimidines and pyridofuropyrimido[1,2-a]azepines: new chemical entities (NCE) with anticonvulsive and psychotropic properties

A series of pyridofuropyrrolo[1,2-a]pyrimidines4and of pyridofuropyrimido[1,2-a]azepines5having as precursors a some new condensed furo[2,3-b]pyridines3were synthesized and evaluated for their anticonvulsive and psychotropic properties.

Pyridofuropyrrolo[1,2-a]pyrimidines and pyridofuropyrimido[1,2-a]azepines: new chemical entities (NCE) with anticonvulsive and psychotropic properties

A series of pyridofuropyrrolo[1,2-a]pyrimidines4and pyridofuropyrimido[1,2-a]azepines5, with new condensed furo[2,3-b]pyridines3as precursors, were synthesized and evaluated for their anticonvulsive and psychotropic properties.

Risk Factors of High Burden Caregivers of Dementia Patients Institutionalized at Day-Care Centres

We examined which variables are associated with day care centres utilization among caregivers of dementia patients. A cross-sectional analysis of socio-demographic variables, relationship with caring and psychological aspects was conducted in 58 informal caregivers with intense burden. 58.6 % used day care assistance and 41.4 % did not. The results showed the importance of the commitment between the caregiver and their family and friends. The use of day care services is independent of the age, gender, educational level, marital status, occupation and relationship with the patient. However, in the multivariate analysis the provision of help by families and friends predicted the use of day care assistance. The bivariate analysis showed a significant relationship between depressive symptoms and self-rated health with day care attendance. Screening the help provision from families and friends in caregivers of dementia patients with intense burden would be relevant to design interventions which delay their institutionalization and reduce costs.

Animal-assisted therapy at Mayo Clinic: The time is now

The animal-human bond refers to an emotional, almost existential, relationship between animals and people. From the time of antiquity, domestic animals were an important source of economic vitality, but with the changing cultural landscape, the companion animal has become a faithful friend. Overwhelming anecdotal evidence supports the healing power of this relationship. We summarize the emerging literature on the neurobiochemical and cardiovascular benefits of companion pet ownership. We address the peer-reviewed data from myriad journal articles assessing the impact of the companion animal on the quality and often the length of life of select patients.

Dietary antioxidant intake and its association with cognitive function in an ethnically diverse sample of US adults

BACKGROUND

Dietary antioxidants can inhibit reactions accompanying neurodegeneration and thus prevent cognitive impairment. We describe associations of dietary antioxidants with cognitive function in a large biracial population, while testing moderation by sex, race, and age and mediation by depressive symptoms.

METHODS

This was a cross-sectional analysis of 1274 adults (541 men and 733 women) aged 30 to 64 years at baseline (mean [standard deviation] = 47.5 [9.3]) in the Healthy Aging in Neighborhoods of Diversity Across the Lifespan Study, Baltimore city, MD. Cognitive performance in the domains of memory, language/verbal, attention, spatial, psychomotor speed, executive function, and global mental status were assessed. The 20-item Center for Epidemiologic Studies Depression Scale was used to measure depressive symptoms. Dietary intake was assessed with two 24-hour recalls, estimating daily consumption of total carotenoids and vitamins A, C, and E per 1000 kcal.

RESULTS

Among key findings, 1 standard deviation (∼ 2.02 mg/1000 kcal) higher vitamin E was associated with a higher score on verbal memory, immediate recall (β = +0.64 [0.19], p = .001), and better language/verbal fluency performance (β = +0.53 [0.16], p = .001), particularly among the younger age group. Women with higher vitamin E intake (β = +0.68 [0.21], p = .001) had better performance on a psychomotor speed test. The vitamin E-verbal memory association was partially mediated by depressive symptoms (proportion mediated = 13%-16%).

CONCLUSIONS

In sum, future cohort studies and dietary interventions should focus on associations of dietary vitamin E with cognitive decline, specifically for domains of verbal memory, verbal fluency, and psychomotor speed.

Building capacity for dementia care in Latin America and the Caribbean

Latin America and the Caribbean (LAC) have limited facilities and professionals trained to diagnose, treat, and support people with dementia and other forms of cognitive impairment. The situation for people with dementia is poor, and worsening as the proportion of elderly in the general population is rapidly expanding. We reviewed existing initiatives and provided examples of actions taken to build capacity and improve the effectiveness of individuals, organizations, and national systems that provide treatment and support for people with dementia and their caregivers. Regional barriers to capacity building and the importance of public engagement are highlighted. Existing programs need to disseminate their objectives, accomplishments, limitations, and overall lessons learned in order to gain greater recognition of the need for capacity-building programs.

Sleep complaints and incident disability in a community-based cohort study of older persons

OBJECTIVE

Sleep complaints are associated with adverse health consequences. We hypothesized that non-disabled older persons with more sleep complaints have an increased risk of developing disability.

METHODS

Subjects included 908 older clergy participating in the Religious Order Study without clinical dementia, history of stroke, or Parkinson disease. At baseline, participants rated their difficulty falling asleep, frequency of nocturnal awakenings, sleep efficacy, and napping frequency, from which a summary dyssomnia measure was derived. Self-report assessment of disability included instrumental activities of daily living (IADLs), basic activities of daily living (ADLs), and Rosow-Breslau mobility disability at baseline and at annual evaluations.

RESULTS

Mean follow-up was 9.6 (SD: 4.2) years. At baseline, more than 60% had one or more sleep complaints. In a series of Cox proportional hazards models controlling for age, sex, and education, a one-point higher dyssomnia score at baseline was associated with about 20% increased risk of IADL disability (hazard ratio: 1.20; 95% confidence interval [CI]: 1.04-1.39; χ(2)1 = 7.62; p <0.05), about 27% increased risk of ADL disability (hazard ratio: 1.27; 95% CI: 1.10-1.47; χ(2)1 = 12.15; p <0.01), and about 27% increased risk of mobility disability (hazard ratio: 1.27; 95% CI: 1.09-1.48; χ(2)1 = 11.04; p <0.01). These associations did not vary by age, sex, or education and remained significant after controlling for potential confounders including body mass index, chronic medical conditions, and several common medications. Controlling for depressive symptoms attenuated the association between sleep complaints and incident IADL and ADL disabilities but the association between sleep complaints and incident mobility disability remained significant.

CONCLUSION

Non-disabled older adults with more sleep complaints have an increased risk of developing disability.

What causes grief in dementia caregivers?

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease in the world. Most AD patients become dependent on their relatives, i.e. family caregivers. Providing care to a person with AD influences caregiver's life and leads to feelings of grief, which often precede caregiver depression. The purpose of the article was to evaluate the Meuser and Marwit Caregiver Grief Inventory (MM-CGI-50) for use in Polish family caregivers and to find out determinants of grief of family caregivers of AD individuals living in Poland. A sample of 151 spouse and adult child caregivers of community-dwelling AD patients (95 females and 56 males) was interviewed to determine the influence of such factors as caregiver's age, gender, family relation to the care recipient (CR) and caregiving-related changes in caregiver's working time, leisure time and material status to find out the impact of caregiving role on intensity of caregiver grief. Caregiver grief was measured by means of MM-CGI-50. Additionally, carers were administered a questionnaire including patient's and caregiver's demographics. Also, CR's dementia assessment was informant-based and determined with investigator-administered clinical dementia rating (CDR) scale. Of all analyzed factors, only caregiver's informant dementia rating significantly influenced caregiver grief. To conclude, the effect of caregiver's age, gender, family relation to the CR and caregiving-related changes in caregiver's working time; leisure time and material status could not be found. To add, MM-CGI-50 can be effectively used to assess grief in Polish family caregivers of AD patients.

Malnutrition in care home residents with dementia

OBJECTIVES

To investigate the malnutrition prevalence in Dutch care home residents with dementia over the years. Secondly, to examine the relationship of malnutrition and dementia and the role of care dependency and co-morbidity within this relationship.

DESIGN

This study is a secondary analysis of data of the annual independent Dutch National Prevalence Measurement of Care Problems of Maastricht University. The design involves a cross-sectional, multicenter point prevalence measurement.

SETTING

Care homes.

PARTICIPANTS

75399 residents older than 65 years (4523 resident with dementia) participated over 5 years (2006-2010). Sixty organizations measured 4 times, 31 organizations 3 times, 68 organizations 2 times, 511 organizations 1 time.

MEASUREMENTS

A standardized questionnaire was used to register amongst others data of weight, height, nutritional intake, undesired weight loss, comorbidity, dementia, and care dependency.

RESULTS

The study was able to show that there is a significant decline in malnutrition prevalence in the group of non-demented residents over the years (Non-demented group p <0.001). The prevalence of malnutrition in the demented group showed no significant reduction over the years. GEE analysis showed that malnutrition and dementia are related and that care dependency and age are important influencing factors in this relation.

CONCLUSION

The results show that compared to the non-demented residents, the prevalence of malnutrition does not decline in demented care home residents over the years. Moreover, the findings of this study stress that malnutrition and dementia are related, while care dependency and age are confounding factors in this relationship.

Can Alzheimer's disease be prevented?

Alzheimer's disease (AD) is the most common form of dementia. Survival time for an AD patient is generally 4 to 6 years after diagnosis, however, survival time can be as long as 20 years from the detection of initial symptoms, which can surface in the 30s, 40s, and beyond. This window of opportunity suggests that many people can prolong their life with life-changing choices related to diet, exercise, nutritional supplements, and nutraceuticals. This was emphasized in many recent studies and was described in detail in the book "Minimizing the Risk of Alzheimer's Disease" published in the USA in 2012.

Biomarkers of Alzheimer's disease among Mexican Americans

BACKGROUND

Mexican Americans are the fastest aging segment of the U.S. population, yet little scientific literature exists regarding the Alzheimer's disease (AD) among this segment of the population. The extant literature suggests that biomarkers of AD will vary according to race/ethnicity though no prior work has explicitly studied this possibility. The aim of this study was to create a serum-based biomarker profile of AD among Mexican American.

METHODS

Data were analyzed from 363 Mexican American participants (49 AD and 314 normal controls) enrolled in the Texas Alzheimer's Research & Care Consortium (TARCC). Non-fasting serum samples were analyzed using a luminex-based multi-plex platform. A biomarker profile was generated using random forest analyses.

RESULTS

The biomarker profile of AD among Mexican Americans was different from prior work from non-Hispanic populations with regards to the variable importance plots. In fact, many of the top markers were related to metabolic factors (e.g., FABP, GLP-1, CD40, pancreatic polypeptide, insulin-like-growth factor, and insulin). The biomarker profile was a significant classifier of AD status yielding an area under the receiver operating characteristic curve, sensitivity, and specificity of 0.77, 0.92, and 0.64, respectively. Combining biomarkers with clinical variables yielded a better balance of sensitivity and specificity.

CONCLUSION

The biomarker profile for AD among Mexican American cases is significantly different from that previously identified among non-Hispanic cases from many large-scale studies. This is the first study to explicitly examine and provide support for blood-based biomarkers of AD among Mexican Americans. Areas for future research are highlighted.

Measuring Alzheimer disease progression with transition probabilities: estimates from NACC-UDS

OBJECTIVES

Estimate the probabilities, for Alzheimer's disease (AD) patients, of transitioning between stages of disease severity (mild, moderate, severe, dead) and care settings (community, institutional).

METHODS

Data were compiled by the National Alzheimer Coordinating Center. The main analyses were limited to 3,852 patients who were 50 years old, diagnosed with possible/probable AD and had at least two center visits. A multinomial logistic model accounting for patient and center level correlation was used to calculate transition probabilities between stages of the Clinical Dementia Rating (CDR). Separately we calculated the probabilities of being institutionalized based on CDR stage. Both analyses controlled for baseline age, time between visits, sex, marital status, whether white, whether Hispanic and number of years of education.

RESULTS

The annual probabilities of dying for patients in mild, moderate and severe health states were 5.5%, 21.5% and 48.0%, respectively, while the annual probabilities for institutionalization were 1.2%, 3.4% and 6.6%, respectively. The majority of mild and moderate patients remain in the same health state after one year, 77.4% and 50.1% respectively. Progressing patients are most likely to transition one stage, but 1.3% of mild patients become severe in one year. Some patients revert to lower severity stages, 7% from moderate to mild.

CONCLUSIONS

Transition probabilities to higher CDR stages and to institutionalization are lower than those published previously, but the probability of death is higher. These results are useful for understanding AD progression and can be used in simulation models to evaluate costs and compare new treatments or policies.

A depressive endophenotype of mild cognitive impairment and Alzheimer's disease

BACKGROUND

Alzheimer's disease (AD) is a devastating public health problem that affects over 5.4 million Americans. Depression increases the risk of Mild Cognitive Impairment (MCI) and AD. By understanding the influence of depression on cognition, the potential exists to identify subgroups of depressed elders at greater risk for cognitive decline and AD. The current study sought to: 1) clinically identify a sub group of geriatric patients who suffer from depression related cognitive impairment; 2) cross validate this depressive endophenotype of MCI/AD in an independent cohort.

METHODS AND FINDINGS

Data was analyzed from 519 participants of Project FRONTIER. Depression was assessed with the GDS30 and cognition was assessed using the EXIT 25 and RBANS. Five GDS items were used to create the Depressive endophenotype of MCI and AD (DepE). DepE was significantly negatively related to RBANS index scores of Immediate Memory (B=-2.22, SE=.37, p<0.001), visuospatial skills (B=-1.11, SE=0.26, p<0.001), Language (B=-1.03, SE=0.21, p<0.001), Attention (B=-2.56, SE=0.49, p<0.001), and Delayed Memory (B=-1.54, SE = 037, p<0.001), and higher DepE scores were related to poorer executive functioning (EXIT25; B=0.65, SE=0.19, p=0.001). DepE scores significantly increased risk for MCI diagnosis (odds ratio [OR] = 2.04; 95% CI=1.54-2.69). Data from 235 participants in the TARCC (Texas Alzheimer's Research & Care Consortium) were analyzed for cross-validation of findings in an independent cohort. The DepE was significantly related to poorer scores on all measures, and a significantly predicted of cognitive change over 12- and 24-months.

CONCLUSION

The current findings suggest that a depressive endophenotype of MCI and AD exists and can be clinically identified using the GDS-30. Higher scores increased risk for MCI and was cross-validated by predicting AD in the TARCC. A key purpose for the search for distinct subgroups of individuals at risk for AD and MCI is to identify novel treatment and preventative opportunities.

Alzheimer's disease, dementia, mild cognitive impairment and the menopause: a 'window of opportunity'?

Alzheimer's disease (AD) is not an inevitable consequence of aging and may be modified by both adverse and protective factors. The pathological changes of AD commence in midlife and AD has a long preclinical phase that may be diagnosed by biomarkers in the cerebrospinal fluid and by brain MRI. New clinical criteria for the diagnosis of AD dementia and AD mild cognitive impairment (MCI) have been proposed. MCI and dementia are frequently the result of AD and cerebrovascular disease combined. Over the age of 85 years, MCI and dementia are more common in women than in men. Women with a surgical premature menopause have an increased risk of MCI and AD. Menopausal hormone therapy from the menopause to the age of 60 years, when any risks of menopausal hormone therapy are extremely small, may provide a 'window of opportunity' to reduce the risk of MCI and AD in later life. Many measures may help to prevent, delay or minimize AD in both women and men and should be actively encouraged.

Apolipoprotein E levels in the cerebrospinal fluid of north Indian patients with Alzheimer's disease

The etiology of Alzheimer's disease (AD) is multifactorial involving both genetic and environmental factors. Apolipoprotein E (ApoE) gene plays a pivotal role in risk and age of onset of AD. Although it is broadly accepted that ApoE genotype is linked to the pathogenesis of AD, there are still controversial results regarding the association of ApoE levels in cerebrospinal fluid (CSF) with the occurrence of AD. Some studies have shown a positive correlation between CSF ApoE levels and AD, whereas others showed no link. In this study, we measured ApoE levels to assess the usefulness of CSF ApoE as a diagnostic marker of AD by comparing the levels in 3 patient groups and in control participants. No significant difference was observed in CSF ApoE concentrations between the patients with AD and the controls. So, it appears that CSF ApoE measurement does not offer any diagnostic advantage for AD.

Gene regulation as a potential avenue for the treatment of neurodegenerative disorders

BACKGROUND

As more people live to an older age, the frequency of diseases associated with longer life begins to increase. Neurodegenerative disorders are the worst of these in that there is now no treatment that offers any real improvement. For this reason, any new avenue of research that could lead to a treatment needs to be rigorously pursued. In many cases, neurodegenerative diseases are associated with the expression of a protein with an altered conformation or that generates a breakdown product associated with the cause. Clearly, the prevention of this process is a key therapeutic target.

OBJECTIVE

In this review, the potential for regulating gene expression to prevent or reverse neurodegenerative disease is explored.

CONCLUSIONS

Whereas much research has been directed at the proteins associated with neurodegeneration, understanding what controls their expression presents a new way this issue could be studied.

The multilingual naming test in Alzheimer's disease: clues to the origin of naming impairments

The current study explored the picture naming performance of patients with Alzheimer’s disease (AD). First, we evaluated the utility of the multilingual naming test (MINT; Gollan et al., 2011), which was designed to assess naming skills in speakers of multiple languages, for detecting naming impairments in monolingual AD and amnestic mild cognitive impairment (MCI). If the MINT were sensitive to linguistic impairment in AD, using it in clinical practice might have advantages over using tests exclusively designed for English monolinguals. We found that the MINT can be used with both monolinguals and bilinguals: A 32-item subset of the MINT is best for distinguishing monolingual patients from controls, while the full MINT is best for assessing degree of bilingualism and language dominance in bilinguals. We then investigated the cognitive mechanisms underlying naming impairment in AD. To this end, we explored which MINT item characteristics best predicted performance differences between monolingual patients and controls. We found that contextual diversity and imageability, but not word frequency (nor words’ number of senses), contributed unique variance to explaining naming impairments in AD. These findings suggest a semantic component to the naming impairment in AD (modulated by names’ semantic richness and network size).

Doença de Alzheimer: declínio funcional e estágio da demência

OBJETIVOS: Verificar como o estágio da doença de Alzheimer se correlaciona com a capacidade funcional do idoso segundo a Medida de Independência Funcional. MÉTODOS: Trata-se de estudo observacional e transversal envolvendo idosos com diagnóstico de doença de Alzheimer e seus cuidadores. Para coleta de dados utilizou-se a Medida de Independência Funcional e a escala de Avaliação Clínica de Demência. RESULTADOS: A amostra foi composta por 67 idosos com média de idade de 79 anos. Demência grave foi encontrada em 46,3%, demência moderada em 22,4% e demência leve em 31,3%. As médias da Medida de Independência Funcional encontradas foram 107,9, 84,5 e 39,7 em idosos com demência leve, moderada e grave, respectivamente. Encontrou-se correlação entre o nível de independência funcional e o estágio de demência (p<0,001). CONCLUSÃO: O estágio de demência é um fator preditivo importante do comprometimento funcional de idosos com doença de Alzheimer.

Characterization of Mexican Americans with mild cognitive impairment and Alzheimer's disease

The purpose of the study was to provide characterization of Mexican Americans who meet criteria for Alzheimer's disease (AD) and mild cognitive impairment (MCI). For the study, 1,069 participants ages 40 and above who self-identified as either non-Hispanic white (n = 633) or Mexican American (n = 436) were recruited using a community-based participatory research approach. Global cognition was assessed via the Mini-Mental State Examination (MMSE), dementia severity by the Clinical Dementia Rating Scale, and depression via the Geriatric Depression Scale 30-item version. Age, gender, education, ApoE ε4 allele frequency, and diabetic diagnoses were also analyzed. The findings showed that Mexican Americans (normal controls, MCI, and AD) were younger, less highly educated, performed more poorly on the MMSE, endorsed more symptoms of depression, were more likely to be diagnosed with diabetes, and possessed the ApoE ε4 allele less frequently. Age was the only significant risk factor for cognitive dysfunction (AD/MCI) among Mexican Americans (OR = 1.06, 95% CI = 1.03-1.09). Age (B = 0.07, std = 0.02, p < 0.001) and ApoE ε4 presence (B = 0.9, std = 0.4, p = 0.02) were significantly related to increased disease severity. Given the rapidly growing and aging Mexican American population, there is a substantial need for research into cognitive aging, MCI, and AD among this ethnic group. The current findings hold important implications for both clinic and research settings and point to additional research needs.

Effect of study partner on the conduct of Alzheimer disease clinical trials

OBJECTIVE

Alzheimer disease (AD) dementia clinical trials require 2 participants: a patient and a study partner. We assessed the prevalence of study partner types and how these types associate with patient-related outcome measures.

METHODS

Retrospective analyses of 6 Alzheimer's disease cooperative study (ADCS) randomized clinical trials were conducted. Study partners were categorized as spouse, adult child, or other. Prevalence of study partner type and associations between study partner type and trial outcomes including study completion and placebo decline on the mini-mental state examination, the Alzheimer's disease assessment scale-cognitive subscale, the clinical dementia rating scale sum of the boxes score, and the ADCS-activities of daily living were examined.

RESULTS

More participants (67%) enrolled with spouses than adult children (26%) or other study partners (7%). Participants with spouse partners had a lower dropout rate (25%) than those with adult child (32%) or other study partners (34%); only the difference vs. others was statistically significant. Participants with adult child and other partners randomized to placebo performed worse at baseline than those with spouse partners on the ADCS-activities of daily living (p = 0.04), but were not different at 18 months. There were no differences at baseline for the mini-mental state examination, clinical dementia rating scale sum of the boxes score, or Alzheimer's disease assessment scale-cognitive subscale. In multivariate models of the rates of change over time among placebo participants, no differences among study partner groups reached statistical significance.

CONCLUSIONS

Patients with nonspouse caregivers less frequently participate in AD dementia trials. Increased enrollment of AD patients with nonspouse caregivers may require additional recruitment and retention strategies.

Aging-related changes in blood-brain barrier integrity and the effect of dietary fat

BACKGROUND

Disturbances in blood-brain barrier (BBB) integrity contribute to the onset and progression of neurodegenerative diseases including Alzheimer's disease (AD) and vascular dementia (VaD). Aging is positively associated with AD and VaD risk, but this may reflect comorbidities or the effects of other chronic modulators of vascular function such as diet.

OBJECTIVE

To explore putative synergistic effects of aging with diet, in this study genetically unmanipulated mice were maintained on diets enriched in saturated fatty acids (SFA) or cholesterol and compared to mice provided with low-fat (LF) feed formula.

METHODS

The functional integrity of the BBB was assessed following 3, 6 and 12 months of dietary intervention commenced at 6 weeks of age, by determining the brain parenchymal extravasation of immunoglobulin G (IgG).

RESULTS

Mice maintained on the SFA- or cholesterol-enriched diet showed significant parenchymal IgG abundance following 3 months of feeding, concomitant with diminished expression of the tight junction protein occludin. LF control mice had essentially no evidence of BBB disturbances. Six months of SFA feeding exacerbated the difference in IgG abundance compared to the LF mice. At 12 months of feeding, the control LF mice also had significant parenchymal IgG that was comparable to mice fed the SFA- or cholesterol-enriched diet for 3 months. However, there may have been an adaptation to the fat-enriched diets because SFA and cholesterol did not exacerbate IgG parenchymal accumulation beyond 6 months of feeding.

CONCLUSION

Collectively, the study suggests that diets enriched in SFA or cholesterol accelerate the onset of BBB dysfunction that otherwise occurs with aging.