Metabolic syndrome and cognitive decline in French elders: the Three-City Study

Sex Disparity in the Association of Metabolic Syndrome with Cognitive Impairment

Background/Objectives: Metabolic syndrome (MS) is a constellation of several cardiometabolic risk factors. We investigated sex disparity in the associations between MS and cognitive impairment using cross-sectional data from Taiwan Biobank. Methods: We determined the associations of MS and its five components with cognitive impairment (mini-mental state examination, MMSE < 24) and the five domains of MMSE using logistic regression analyses. Results: A total of 7399 men and 11,546 women were included, and MS was significantly associated with cognitive impairment only in women (adjusted OR 1.48, 95% CI 1.29-1.71, p = 0.001) (p for interaction 0.005). In women, the association with MS was significant in orientation (adjusted OR 1.21, 95% CI 1.07-1.37, p = 0.003), memory (adjusted OR 1.12, 95% CI 1.01-1.25, p = 0.034) and design copying (adjusted OR 1.41, 95% CI 1.23-1.62, p = 0.001) (p value for interaction 0.039, 0.023, and 0.093, respectively). Among the components of MS, a large waist circumference (adjusted OR 1.25, 95% CI 1.08-1.46, p = 0.003), high fasting glucose (adjusted OR 1.16, 95% CI 1.00-1.34, p = 0.046), and low HDL cholesterol (adjusted OR 1.16, 95% CI 1.00-1.34, p = 0.049) were significantly associated with cognitive impairment in women. Conclusions: Our findings suggest that sex has a significant influence on the association between MS and cognitive dysfunction, especially in orientation and memory.

Sleep Quality, Nutrient Intake, and Social Development Index Predict Metabolic Syndrome in the Tlalpan 2020 Cohort: A Machine Learning and Synthetic Data Study

This study investigated the relationship between Metabolic Syndrome (MetS), sleep disorders, the consumption of some nutrients, and social development factors, focusing on gender differences in an unbalanced dataset from a Mexico City cohort. We used data balancing techniques like SMOTE and ADASYN after employing machine learning models like random forest and RPART to predict MetS. Random forest excelled, achieving significant, balanced accuracy, indicating its robustness in predicting MetS and achieving a balanced accuracy of approximately 87%. Key predictors for men included body mass index and family history of gout, while waist circumference and glucose levels were most significant for women. In relation to diet, sleep quality, and social development, metabolic syndrome in men was associated with high lactose and carbohydrate intake, educational lag, living with a partner without marrying, and lack of durable goods, whereas in women, best predictors in these dimensions include protein, fructose, and cholesterol intake, copper metabolites, snoring, sobbing, drowsiness, sanitary adequacy, and anxiety. These findings underscore the need for personalized approaches in managing MetS and point to a promising direction for future research into the interplay between social factors, sleep disorders, and metabolic health, which mainly depend on nutrient consumption by region.

Metabolic syndrome and cognitive deficits in the Greek cohort of Epirus Health Study

BACKGROUND

Metabolic syndrome is considered an important risk factor for cognitive decline and dementia. However, the evidence in middle-aged individuals is still conflicting. The aim of the study was to explore the association between metabolic syndrome and its individual components with cognitive function and to investigate possible interaction between sex, age and genetic predisposition for metabolic syndrome and Alzheimer's disease in a middle-aged Greek cohort.

METHODS

A total of 2,077 healthy adults (mean age: 46.7 years) were included in the primary cross-sectional analysis and 305 of them in secondary prospective analyses. Metabolic syndrome was defined by the revised National Cholesterol Education-Adult Treatment Panel III and the International Diabetes Federation criteria. Cognitive function was measured primarily with the Trail Making, Verbal fluency and Logical Memory test, and in secondary prospective analyses with online versions of Posner cueing task, an emotional recognition task, Corsi block-tapping task and Stroop task.

RESULTS

Multivariable linear regressions showed an association of metabolic syndrome with lower performance in attention (β=1.62 seconds, 95% CI=0.20, 3.04) and memory (β=-0.62 words, 95% CI=-1.19, -0.05) that could be driven by associations with elevated fasting glucose and abdominal obesity. Similar associations were observed in the secondary prospective analyses.

CONCLUSION

In summary, metabolic syndrome was associated with cognitive deficits in domains related with the cognitive profile of vascular cognitive impairment.

Longitudinal association of hypertension and dyslipidemia with cognitive function in community-dwelling older adults: the SONIC study

The associations among cognitive function, hypertension, and dyslipidemia in older adults are controversial. Therefore, we investigated the associations among cognitive decline, hypertension, dyslipidemia, and their combination in community-dwelling older people in their 70s, 80s, and 90s in the long-term observational Septuagenarians, Octogenarians, Nonagenarians, Investigation with Centenarians (SONIC) study. We administered the Montreal Cognitive Assessment Japanese version (MoCA-J) by trained geriatricians and psychologists, and conducted blood testing and blood pressure (BP) measuring by medical staff involving 1186 participants. We performed multiple regression analysis to assess the relationships among hypertension, dyslipidemia, their combination, and lipid and BP levels with cognitive function at the 3-year follow-up after adjusting for covariate factors. At the baseline, the percentage of the combination of hypertension and dyslipidemia was 46.6% (n = 553), hypertension was 25.6% (n = 304), dyslipidemia was 15.0% (n = 178), and that without hypertension or dyslipidemia was 12.7% (n = 151). Conducting multiple regression analysis, no significant correlation was found between the combination of hypertension and dyslipidemia and MoCA-J score. In the group with the combination, high high-density lipoprotein cholesterol (HDL) levels resulted in higher MoCA-J scores at the follow-up (β = 0.06; P < 0.05) and high diastolic BP (DBP) also resulted in higher MoCA-J scores (β = 0.08; P < 0.05). The results suggest that high HDL and DBP levels of individuals with HT & DL and high SBP levels of individuals with HT were associated with cognitive function in community-dwelling older adults. In the SONIC study, which is an epidemiological study of Japanese older persons aged 70 years or older, a disease-specific examination suggested that high HDL and DBP levels of individuals with hypertension & dyslipidemia and high SBP levels of individuals with hypertension were associated with maintaining cognitive function in community-dwelling older adults.

Associations of metabolic syndrome, its severity with cognitive impairment among hemodialysis patients

BACKGROUND

In the general population, metabolic syndrome (MetS) is associated with increased risk of cognitive impairment, including global and specific cognitive domains. These associations are not well studied in patients undergoing hemodialysis and were the focus of the current investigation.

METHODS

In this multicenter cross-sectional study, 5492 adult hemodialysis patients (3351 men; mean age: 54.4 ± 15.2 years) treated in twenty-two dialysis centers of Guizhou, China were included. The Mini-Mental State Examination (MMSE) was utilized to assess mild cognitive impairment (MCI). MetS was diagnosed with abdominal obesity, hypertension, hyperglycemia, and dyslipidemia. Multivariate logistic and linear regression models were used to examine the associations of MetS, its components, and metabolic scores with the risk of MCI. Restricted cubic spline analyses were performed to explore the dose-response associations.

RESULTS

Hemodialysis patients had a high prevalence of MetS (62.3%) and MCI (34.3%). MetS was positively associated with MCI risk with adjusted ORs of 1.22 [95% confidence interval (CI) 1.08-1.37, P = 0.001]. Compared to no MetS, adjusted ORs for MCI were 2.03 (95% CI 1.04-3.98) for 22.51 (95% CI 1.28-4.90) for 3, 2.35 (95% CI 1.20-4.62) for 4, and 2.94 (95% CI 1.48-5.84) for 5 components. Metabolic syndrome score, cardiometabolic index, and metabolic syndrome severity score were associated with increased risk of MCI. Further analysis showed that MetS was negatively associated with MMSE score, orientation, registration, recall and language (P < 0.05). Significant interaction effect of sex (P for interaction = 0.012) on the MetS-MCI was observed.

CONCLUSION

Metabolic syndrome was associated with MCI in hemodialysis patients in a positive dose-response effect.

A one-year view on the association of metabolic syndrome and cognitive function in bipolar disorder - Preliminary data

BACKGROUND

Individuals with bipolar disorder have a high prevalence of metabolic syndrome and an increased risk for cognitive deficits. The aim of this longitudinal study was to investigate the trajectory of cognitive decline in dependence of metabolic syndrome over a one-year interval.

METHODS

52 well-diagnosed individuals with bipolar disorder, euthymic at baseline and follow-up (n = 17 with metabolic syndrome vs. n = 35 without metabolic syndrome) were investigated with a comprehensive neurocognitive test battery (Trail Making Test A/B, Digit Symbol Test, California Verbal Leaning Test, or the Verbal Learning and Memory Test respectively) twice within the interval of one year.

RESULTS

Patients with bipolar disorder and additional metabolic syndrome performed significantly worse in the domain of psychomotor and processing speed/attention than patients without metabolic syndrome at test point one. No deteriorating effects of metabolic syndrome on the cognitive domain scores and overall cognitive performance were found at the one-year follow up. However, no cognitive decline could be reported in both groups.

LIMITATIONS

Time interval, small sample size and selection of metabolic syndrome affected patients were the major limitations of this study.

CONCLUSION

There was no association of metabolic syndrome on the one-year trajectory of cognitive function in bipolar disorder. Future studies should expand the observation period and investigate larger samples.

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

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

Metabolic syndrome and cognition: A systematic review across cognitive domains and a bibliometric analysis

The aim of this review is to investigate the association between metabolic syndrome (MetS) and cognitive decline in distinct cognitive domains, and to perform a complementary study description through the bibliometric analysis. PubMed and Scopus databases were searched from inception to 15 December 2021 to identify longitudinal studies that examined the association of MetS with incident decline, in order to prevent reverse causality. The Preferred Reporting Items for Systematic Review and Meta-Analysis checklist was used to conduct the present systematic review. Thirty studies were included and results were analyzed across the cognitive domains of global cognition, memory, executive functions, attention, visuoconstructive abilities, and language. The majority of the studies reviewed did not report statistically significant results for most cognitive domains investigated, and decline in specific cognitive domains was not consistently associated with the presence of MetS. Meta-analyses were not conducted due to the high degree of between-study heterogeneity regarding the MetS definitions, the cognitive domains examined, the specific tests used for each cognitive domain and the different measures of association used. Bibliometric analysis revealed that most studies are conducted by research teams from USA and China, and that cognitive tasks that reflect real-life abilities are rarely examined. Future studies should employ larger sample sizes, longer follow-up periods, a global consensus for MetS definition and standardized tests of the above mentioned cognitive domains as well as problem-solving tasks with high sensitivity and specificity to clarify the impact of MetS on cognition and its underlying mechanisms.

Sex Differences in the Association Between Metabolic Dysregulation and Cognitive Aging: The Health and Retirement Study

BACKGROUND

Dysregulation of some metabolic factors increases the risk of dementia. It remains unclear if overall metabolic dysregulation, or only certain components, contribute to cognitive aging and if these associations are sex specific.

METHODS

Data from the 2006-2016 waves of the Health and Retirement Study (HRS) was used to analyze 7 103 participants aged 65 and older at baseline (58% women). We created a metabolic-dysregulation risk score (MDRS) composed of blood pressure/hypertension status, glycosylated hemoglobin (HbA1c)/diabetes status, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and waist circumference, and assessed cognitive trajectories from repeated measures of the HRS-Telephone Interview for Cognitive Status (HRS-TICS) over 10 years of follow-up. Linear mixed-effects models estimated associations between MDRS or individual metabolic factors (biomarkers) with mean and change in HRS-TICS scores and assessed sex-modification of these associations.

RESULTS

Participants with higher MDRSs had lower mean HRS-TICS scores, but there were no statistically significant differences in rate of decline. Sex stratification showed this association was present for women only. MDRS biomarkers revealed heterogeneity in the strength and direction of associations with HRS-TICS. Lower HRS-TICS levels were associated with hypertension, higher HbA1c/diabetes, and lower HDL-C and TC, whereas faster rate of cognitive decline was associated with hypertension, higher HbA1c/diabetes, and higher TC. Participants with higher HbA1c/diabetes presented worse cognitive trajectories. Sex differences indicated that women with higher HbA1c/diabetes to have lower HRS-TICS levels, whereas hypertensive males presented better cognitive trajectory.

CONCLUSIONS

Our results demonstrate that metabolic dysregulation is more strongly associated with cognition in women compared with men, though sex differences vary by individual biomarker.

Mild cognitive impairment in patients with systemic sclerosis and features analysis

Objective

Nervous system damage in patients with SSc has recently attracted attention. In this study, we aimed to explore mild cognitive impairment (MCI) in SSc patients and the characteristics of these patients.

Methods

A total of 103 SSc patients were consecutively enrolled from July 2018 to May 2019, and 97 matched healthy individuals were also included as controls. Brief cognitive tests, such as the Beijing version of the Montreal Cognitive Assessment (MoCA-BJ), were used to assess the cognitive function of all subjects. We compared the differences in MCI between SSc patients and healthy controls, as well as the differences in demographic and clinical features between SSc patients with and without MCI. Associations of quantitative demographic and clinical features with MoCA-BJ scores in the SSc patients were also evaluated.

Results

The score of MoCA-BJ was lower in the SSc group compared with those in the healthy group [24 (9–30) vs 26 (15–30), P &lt; 0.001]. MCI (MoCA-BJ score ≤ 25) was found in 61.2% (63/103) of the enrolled SSc patients but only in 27.8% (27/97) of the healthy individuals. Other tests evaluating some of the specific domains of cognitive functions showed that the SSc patients had impaired memory, attention and executive ability. Compared with SSc patients without MCI, SSc patients with MCI had lower education level, total serum protein and serum albumin but higher ANA positivity.

Conclusion

MCI is common in patients with SSc and should be drawn to the attention of rheumatologists. Lower education level, malnutrition and higher ANA positivity were closely related to the cognitive dysfunctions in SSc patients, providing directions for further interventions.

Early metabolic impairment as a contributor to neurodegenerative disease: Mechanisms and potential pharmacological intervention

The metabolic syndrome comprises a family of clinical and laboratory findings, including insulin resistance, hyperglycemia, hypertriglyceridemia, low high-density lipoprotein cholesterol levels, and hypertension, in addition to central obesity. The syndrome confers a high risk of cardiovascular mortality. Indeed, metabolic dysfunction has been shown to cause a direct insult to smooth muscle and endothelial components of the vasculature, which leads to vascular dysfunction and hyperreactivity. This, in turn, causes cerebral vasoconstriction and hypoperfusion, eventually contributing to cognitive deficits. Moreover, the metabolic syndrome disrupts key homeostatic processes in the brain, including apoptosis, autophagy, and neurogenesis. Impairment of such processes in the context of metabolic dysfunction has been implicated in the pathogenesis of neurodegenerative diseases, including Alzheimer, Parkinson, and Huntington diseases. The aim of this review is to elucidate the role that the metabolic syndrome plays in the pathogenesis of the latter disorders, with a focus on the role of perivascular adipose inflammation in the peripheral-to-central transduction of the inflammatory insult. This review delineates common signaling pathways that contribute to these pathologies. Moreover, the role of therapeutic agents aimed at treating the metabolic syndrome, as well as their risk factors that interfere with the aforementioned pathways, are discussed as potential interventions for neurodegenerative diseases.

Metabolic Syndrome and High-Obesity-Related Indices Are Associated with Poor Cognitive Function in a Large Taiwanese Population Study Older than 60 Years

Metabolic syndrome (MetS) is prevalent in Taiwan; however, the association between MetS and cognitive function is unclear. The aim of this study was to explore the associations between MetS, its components, and obesity-related indices with cognitive function in a large Taiwanese cohort. We enrolled a total of 28,486 participants who completed the Mini-Mental State Examination (MMSE) questionnaire, which was used to evaluate cognitive function. MetS was defined according to the NCEP-ATP III guidelines and modified criteria for Asians. Ten obesity-related indices were also evaluated: body mass index (BMI), abdominal volume index (AVI), body adiposity index (BAI), waist−hip ratio (WHR), a body shape index (ABSI), lipid accumulation product, waist-to-height ratio (WHtR), conicity index (CI), body roundness index (BRI), and triglyceride glucose index. The prevalence of MetS and its components (except for hypertriglyceridemia) and the number of MetS components increased while the cognitive impairment worsened (from MMSE ≥ 24, 18−23 to 0−17). In addition, increases in all obesity-related index values were associated with a decline in cognitive function (from MMSE ≥ 24, 18−23 to 0−17, ANOVA p < 0.001). Multivariable analysis showed that MetS (p = 0.002), abdominal obesity (p < 0.001), low high-density lipoprotein cholesterol (p = 0.004), and hyperglycemia (p = 0.012) were significantly associated with a low MMSE score. Further, participants with high BMI (p = 0.001), WHR (p < 0.001), WHtR (p < 0.001), BRI (p < 0.001), CI (p < 0.001), BAI (p < 0.001), AVI (p < 0.001), and ABSI (p < 0.001) values were significantly associated with a low MMSE score. Our results show that MetS and its components (except for hypertriglyceridemia and high blood pressure) may lead to cognitive impairment, and that high values of obesity-related indices were associated with poor cognitive function.

Verbal Fluency in Metabolic Syndrome

Metabolic syndrome (MetS) or otherwise insulin resistance (IR) is described as a cluster of several commonly occurring disorders, including abdominal obesity; lipids disorders, such as hypertriglyceridemia; and low levels of high-density-lipoprotein cholesterol (HDL-C), hypertension (≥130/85 mmHg), and carbohydrates disorders, such as impaired fasting glucose or diabetes mellitus type 2. Type 2 diabetes (T2DM) constitutes insulin resistance, which is a strong risk factor for strokes. Patients with MetS are often prone to cognitive decline. Metabolic risk factors, hypertension, and diabetes, amongst them, have been hypothesized to play a great role in the pathogenesis of Alzheimer’s disease (AD) and the development of vascular dementia. For neuropsychological diagnostic and theoretical purposes verbal fluency is defined as a cognitive function that facilitates information retrieval from memory. It engages executive control and other cognitive processes, such as selective attention, selective inhibition, mental set shifting, internal response generation, and self-monitoring, as well as imagination and psychomotor skills. A total of 90 subjects, divided into 2 groups, patients with MetS (45) and healthy controls (45), were assessed. A significant difference in performance was found between the patients and controls, both in the phonetic (p < 0.01) and semantic fluency trials (p < 0.001). The MetS patients produced less words in the letter K and animal categories. The analysis of descriptive statistics shows that the group of patients with metabolic syndrome generated fewer words in both the phonetic and semantic categories. Our study shows that there is an association between metabolic factors and the verbal fluency performance of MetS patients. This is true, especially for phonetic verbal fluency, which is traditionally connected with the frontal cortex. Lower switching signifies possible executive dysfunctions amongst people with MetS. Subjects with this condition generated more diverse words and created less standard associations. This further implies the existence of dysexecutive syndrome and the need for diagnosing patients in this direction and involving this group of people in therapy. The proper correction of MetS components may improve cognitive function.

The Predictive Role of Aberrant Metabolic Parameters and Negative Automatic Thinking on the Cognitive Impairments Among Schizophrenia Patients with Metabolic Syndrome

PURPOSE

The study aimed to clarify the cognitive impairments of schizophrenia with metabolic syndrome while evaluating their potential as risk factors.

PATIENTS AND METHODS

We recruited 153 participants and divided them into three groups according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, criteria and the guideline standards for the prevention and treatment of dyslipidemia in Chinese adults in 2007 for metabolic syndrome, as follows: healthy control group (n = 47); nonmetabolic syndrome group (n = 58); and metabolic syndrome group (n = 48). Psychotic symptoms were evaluated using the Positive and Negative Syndrome Scale. Cognitive function and automatic thinking were estimated using the Montreal Cognitive Assessment Scale, Verbal Fluency Test, and Automatic Thoughts Questionnaire. Serum biochemical parameters were measured by automatic biochemistry analyzer.

RESULTS

One-way ANOVA analysis revealed that differential cognition impairments in schizophrenia patients compared to controls. Furthermore, results of multiple comparisons showed that more serious barriers in orientation, language fluency, and negative automatic thinking existed in the metabolic syndrome group than in the healthy and non-metabolic syndrome groups. Spearman correlation and stepwise linear regression analyses showed that psychopathological symptoms, high waist circumference, and high triglyceride were the predictive factors for negative automatic thoughts, orientation, and language fluency. Those results collectively revealed that high waist circumference, high triglyceride and negative automatic thinking had validity and effectiveness in predicting the cognitive function impairments of the metabolic syndrome group.

CONCLUSION

The present findings strongly supported the notion that aberrant parameters of high waist circumference, high triglyceride and high negative automatic thoughts had validity and effectiveness predictive role for cognitive impairments in the schizophrenics with metabolic syndrome. The schizophrenia patients with metabolic syndrome should receive regular monitoring and adequate treatment for metabolic and psychological risk factors.

Dexibuprofen ameliorates peripheral and central risk factors associated with Alzheimer's disease in metabolically stressed APPswe/PS1dE9 mice

BACKGROUND

Several studies stablished a relationship between metabolic disturbances and Alzheimer´s disease (AD) where inflammation plays a pivotal role. However, mechanisms involved still remain unclear. In the present study, we aimed to evaluate central and peripheral effects of dexibuprofen (DXI) in the progression of AD in APPswe/PS1dE9 (APP/PS1) female mice, a familial AD model, fed with high fat diet (HFD). Animals were fed either with conventional chow or with HFD, from their weaning until their sacrifice, at 6 months. Moreover, mice were divided into subgroups to which were administered drinking water or water supplemented with DXI (20 mg kg-1 d-1) for 3 months. Before sacrifice, body weight, intraperitoneal glucose and insulin tolerance test (IP-ITT) were performed to evaluate peripheral parameters and also behavioral tests to determine cognitive decline. Moreover, molecular studies such as Western blot and RT-PCR were carried out in liver to confirm metabolic effects and in hippocampus to analyze several pathways considered hallmarks in AD.

RESULTS

Our studies demonstrate that DXI improved metabolic alterations observed in transgenic animals fed with HFD in vivo, data in accordance with those obtained at molecular level. Moreover, an improvement of cognitive decline and neuroinflammation among other alterations associated with AD were observed such as beta-amyloid plaque accumulation and unfolded protein response.

CONCLUSIONS

Collectively, evidence suggest that chronic administration of DXI prevents the progression of AD through the regulation of inflammation which contribute to improve hallmarks of this pathology. Thus, this compound could constitute a novel therapeutic approach in the treatment of AD in a combined therapy.

Metabolic Syndrome and Cognition: Follow-Up Study of Chinese Over-55-Year-Olds

BACKGROUND/AIM

Studies of the associations of the metabolic syndrome (MetS) with cognitive function and decline are inconclusive. We investigated the associations of the MetS with cognitive functions in 823 Chinese >55-year-olds followed up over 4.5 years.

METHODS

The relationships between the MetS and baseline and follow-up z-scores of cognitive domain functions were examined using mixed model analysis.

RESULTS

There were specific inverse cross-sectional associations of single cardiometabolic risk factors with cognition, such as hyperglycemia with processing speed (p = 0.045). The MetS was negatively associated with 3 out of 4 cognitive domains (p = 0.018 to p = 0.003), and the count of cardiometabolic risk factors with all cognitive domains (p = 0.025 to p = 0.002). Longitudinally, dyslipidemia was associated with worse decline in memory and learning (p = 0.022). The count of cardiometabolic risk factors was associated with worse declines in cognition (p = 0.032 for global cognition).

CONCLUSION

Among middle-aged and older Asians, an increased number of component cardiometabolic risk factors of the MetS was associated with a worse decline in cognitive function over time.

Metabolic syndrome is associated with poor cognition: a population-based study of 70-year-olds without dementia

Background

Individual conditions of metabolic syndrome (MetS) have been related to dementia; however, their combined impact on the preclinical stage is unknown. We investigated the associations between MetS and domain-specific cognitive function as well as the role of sociodemographic, cardiovascular, and genetic factors.

Methods

Within the Gothenburg H70 Birth Cohort Study-Birth cohort 1944, 1131 dementia-free participants (aged 70 years) were examined during 2014–2016. MetS (central obesity plus at least 2 factors [reduced HDL-cholesterol, elevated triglycerides, blood pressure, or blood glucose]) was identified according to the International Diabetes Federation criteria. Five cognitive domains (memory, attention/perceptual speed, executive function, verbal fluency, visuospatial abilities) were generated after z-standardizing raw scores from 10 neuropsychological tests. Education, heart disease, claudication (indicating peripheral atherosclerosis), and apolipoprotein genotype were ascertained by trained staff. Data were analyzed with linear regression models.

Results

Overall, 618 participants (55%) had MetS. In multiadjusted linear regressions, MetS was related to poorer performance in attention/perceptual speed (β −0.14 [95% CI −0.25, −0.02]), executive function (β −0.12 [95% CI −0.23, −0.01]), and verbal fluency (β −0.19 [95% CI −0.30, −0.08]). These associations were present only among individuals who did not carry any APOE-ε4 allele or were highly educated. However, among those with MetS, high education was related to better cognitive performance. MetS together with comorbid heart disease or claudication was associated with even worse cognitive performance than each alone.

Conclusions

MetS is associated with poor attention/perceptual speed, executive function, and verbal fluency performance. Education, apolipoprotein E-ε4 allele, and comorbid cardiovascular disease influenced the observed associations.

Longitudinal trajectories of metabolic syndrome on different neurocognitive domains: a cohort study from the Taiwan biobank

Metabolic syndrome (MetS) brings considerable effects on cognitive function, but trajectories within remain unclear. We investigated the interactions between distinct MetS components and cognitive domains. A total of 5693 participants from the Taiwan biobank during 2008–2018 were enrolled. Participants were classified as either normal or as having MetS at two time points; i.e., study entry and follow-up. At both the time points, cognitive evaluations using the Mini-Mental State Examination (MMSE) were conducted. The hazard ratios (HRs) of mild cognitive impairment (MCI) and dementia were higher in participants meeting more diagnostic components of MetS. Of the five criteria of MetS, three were significantly associated with MCI and dementia: high blood pressure (MCI: HR = 1.203, p < 0.001; dementia: HR = 1.345, p < 0.001), abdominal obesity (MCI: HR = 1.137, p = 0.006; dementia: HR = 1.442, p < 0.001), and low high-density lipoprotein (HDL) level (MCI: HR = 1.149, p = 0.007; dementia: HR = 1.364, p < 0.001). Of the cognitive domains measured, three were significantly associated with MetS; namely, orientation, language, and visuospatial abilities. Participants who were initially diagnosed with MetS but were normal at follow-up had an HR of 1.374 for dementia (p = 0.019), which was beyond our expectations. The undiminished risk of cognitive decline in subjects returning to normal status illustrated that neural injury caused by MetS takes a long time to get repaired. Consequently, earlier detection and management of adjustable risk factors of MetS should be encouraged to minimize the damage.

Intranasal Insulin for Alzheimer's Disease

Brain insulin signaling contributes to memory function and might be a viable target in the prevention and treatment of memory impairments including Alzheimer's disease. This short narrative review explores the potential of central nervous system (CNS) insulin administration via the intranasal pathway to improve memory performance in health and disease, with a focus on the most recent results. Proof-of-concept studies and (pilot) clinical trials in individuals with mild cognitive impairment or Alzheimer's disease indicate that acute and prolonged intranasal insulin administration enhances memory performance, and suggest that brain insulin resistance is a pathophysiological factor in Alzheimer's disease with or without concomitant metabolic dysfunction. Intranasally administered insulin is assumed to trigger improvements in synaptic plasticity and regional glucose uptake as well as alleviations of Alzheimer's disease neuropathology; additional contributions of changes in hypothalamus-pituitary-adrenocortical axis activity and sleep-related mechanisms are discussed. While intranasal insulin delivery has been conclusively demonstrated to be effective and safe, the recent outcomes of large-scale clinical studies underline the need for further investigations, which might also yield new insights into sex differences in the response to intranasal insulin and contribute to the optimization of delivery devices to grasp the full potential of intranasal insulin for Alzheimer's disease.

Association of mid-life serum lipid levels with late-life brain volumes: The atherosclerosis risk in communities neurocognitive study (ARICNCS)

BACKGROUND

Limited information exists regarding the association between midlife lipid levels and late-life total and regional brain volumes.

METHODS

We studied 1872 participants in the longitudinal community-based Atherosclerosis Risk in Communities Neurocognitive Study. Serum lipid levels were measured in 1987-1989 (mean age, 53 ± 5 years). Participants underwent 3T brain MRI scans in 2011-2013. Brain volumes were measured using FreeSurfer image analysis software. Linear regression models were used to assess the associations between serum lipids and brain volumes modeled in standard deviation (SD) units, adjusting for potential confounders.

RESULTS

In adjusted analyses, one SD higher low-density lipoprotein cholesterol (LDL) levels were associated with larger total brain volumes (β 0.033, 95% CI 0.006-0.060) as well as larger volumes of the temporal (β 0.038, 95% CI 0.003-0.074) and parietal lobes (β 0.044, 95% CI 0.009-0.07) and Alzheimer disease-related region (β 0.048, 95% CI 0.048-0.085). Higher triglyceride levels were associated with smaller total brain volumes (β -0.033, 95% CI -0.060, -0.007). The associations between LDL levels and brain volumes were modified by age (P for interaction <0.001), with higher LDL levels associated with larger total and regional brain volumes only among adults >53 years at baseline, and were attenuated after application of weights to account for informative attrition, although associations with the parietal and Alzheimer's disease-related region remained significant. High-density lipoprotein cholesterol was not associated with brain volumes.

CONCLUSION

Higher LDL levels in late midlife were associated with larger brain volumes later in life, while higher triglyceride levels were associated with smaller brain volumes. These associations were driven by adults >53 years at baseline.

Metabolic Syndrome and Cognitive Trajectories in the Framingham Offspring Study

Metabolic syndrome (MetS) has been linked to increased risk of developing cognitive impairment and dementia including Alzheimer's disease. It remains unclear whether and at what stage in the adult lifespan MetS and its components begin to alter the trajectory of cognitive performance. In the present study, 2,892 Framingham Offspring participants completed health assessments every four years since 1971 and underwent repeat neuropsychological testing from 1999 to 2014. We estimated the associations of levels and changes in cognitive trajectories with hazard of MetS using a joint growth/survival model. All models were adjusted for baseline age, sex, education, and smoking status. Findings showed that both mid-life and late-life MetS were associated with lower level of cognitive functioning but not cognitive trajectories. Associations were strongest among those who were nondemented and apolipoprotein (APOE) ɛ4 noncarriers. In addition, individuals with the most rapid cognitive decline were more likely to have MetS. The pattern of results showed that associations between MetS and cognition varied, depending upon whether the sample was stratified by genetic and cognitive status and whether we considered cognitive performance as a continuous variable or examined categorical groupings. Given that mid-life MetS was associated with poorer cognition at age 55, cognitive changes may occur early during the MetS process. Our findings suggest that those with MetS are at greater risk of dementia given their lower level of cognitive functioning and also suggest that MetS may be a risk factor for decline in the absence of known risk factors including the APOEɛ4 allele.

Association of mild cognitive impairment and metabolic syndrome in patients with hypertension

AIM

The aim of this study was to evaluate the prevalence of mild cognitive impairment (MCI) in patients with hypertension and to evaluate the association of MCI with metabolic syndrome (MetS).

METHODOLOGY

186 subjects with hypertension were evaluated on Montreal Cognitive Assessment (MoCA) and Patient Health Questionnaire (PHQ-9) for cognitive decline and depression, respectively and MetS was diagnosed as per the Consensus definition.

RESULTS

The prevalence of MCI was 65.6 % and that of MetS was 45.7 %. Compared to those without MetS, those with MetS had significantly poorer cognitive functioning on the all cognitive domain of the MoCA, even after controlling for age, education, severity of the depression and duration of illness. Low High-Density Lipoprotein (HDL) was found to have a positive correlation with MoCA. Higher age, lower education, higher duration of illness and use of higher numbers of medications were associated with significantly lower score on MoCA.

CONCLUSION

Presence of MetS among persons with hypertension is associated with cognitive decline. Hence, there is a need to monitor and manage other parameters of MetS among patients with hypertension, to reduce the risk of cognitive decline and future dementia.

The cortisol burden in elderly subjects with metabolic syndrome and its association with low-grade inflammation

BACKGROUND

Elderly people are exposed to an increased load of stressful events and neuro-hormonal stimulation is a key finding in metabolic syndrome and its related disorders.

AIMS

To determine the role of cortisol in elderly subjects, with or without metabolic syndrome (MetS), by means of a national multicentre observational study, AGICO (AGIng and Cortisol).

METHODS

From 2012 to 2017, the AGICO study enrolled n.339 subjects (aged > 65), after obtaining their informed consent. The investigators assessed a cardio-metabolic panel (including electrocardiogram, carotid ultrasonography and echocardiography), the presence of MetS (on Adult Treatment Panel III criteria), a neurological examination (including brain imaging), and cortisol activity (using a consecutive collection of diurnal and nocturnal urine).

RESULTS

In the patients presenting with MetS, the standardized diurnal and nocturnal cortisol excretion rates were 210.7 ± 145.5 and 173.7 ± 118.1 (mean ± standard deviation) μg/g creatinine/12 h; in those without MetS, the standardized diurnal and nocturnal cortisol excretion rates were 188.7 ± 92.7 and 144.1 ± 82.3 μg/g creatinine/12 h, respectively (nocturnal urinary cortisol in patients with MetS versus those without MetS p = 0.05, female patients with MetS vs female patients without MetS, p < 0.025). A significant positive correlation was found between the CRP levels and both the diurnal and nocturnal urinary cortisol levels with r = 0.187 (p < 0.025) and r = 0.411 (p < 0.00000001), respectively.

DISCUSSION

The elderly patients with MetS showed a trend towards increased standardized nocturnal cortisol excretions, with particular regard to the female subjects.

CONCLUSION

The positive correlation between cortisol excretion and low-grade inflammation suggests a common mechanism driving both hormonal and inflammatory changes.

Changes in Metabolic Syndrome Status and Risk of Dementia

This study investigated the effects of changes in metabolic syndrome (MS) status and each component on subsequent dementia occurrence. The study population was participants of a biennial National Health Screening Program in 2009–2010 and 2011–2012 in Korea. Participants were divided into four groups according to change in MS status during the two-year interval screening: sustained normal, worsened (normal to MS), improved (MS to normal), and sustained MS group. Risk of dementia among the groups was estimated from the second screening date to 31 December 2016 using a Cox proportional hazards model. A total of 4,106,590 participants were included. The mean follow-up was 4.9 years. Compared to the sustained normal group, adjusted hazard ratios (aHR) (95% confidence interval) were 1.11 (1.08–1.13) for total dementia, 1.08 (1.05–1.11) for Alzheimer’s disease, and 1.20 (1.13–1.28) for vascular dementia in the worsened group; 1.12 (1.10–1.15), 1.10 (1.07–1.13), and 1.19 (1.12–1.27) for the improved group; and 1.18 (1.16–1.20), 1.13 (1.11–1.15), and 1.38 (1.32–1.44) for the sustained MS group. Normalization of MS lowered the risk of all dementia types; total dementia (aHR 1.18 versus 1.12), Alzheimer’s disease (1.13 versus 1.10), and vascular dementia (1.38 versus 1.19). Among MS components, fasting glucose and blood pressure showed more impact. In conclusion, changes in MS status were associated with the risk of dementia. Strategies to improve MS, especially hyperglycemia and blood pressure, may help to prevent dementia.

Association between Cognitive Function and Clustered Cardiovascular Risk of Metabolic Syndrome in Older Adults at Risk of Cognitive Decline

OBJECTIVES

Metabolic syndrome (MetS) represents a cluster of obesity and insulin resistance-related comorbidities. Abdominal obesity, hypertension, elevated triglyceride and glucose levels are components of MetS and may have a negative effect on cognitive function, but few cognitive studies have examined the combined risk severity. We sought to determine which specific cognitive abilities were associated with MetS in older adults at risk of cognitive decline.

DESIGN

Cross-sectional study.

PARTICIPANTS

108 AIBL Active participants with memory complaints and at least one cardiovascular risk factor.

MEASUREMENTS

Cardiovascular parameters and blood tests were obtained to assess metabolic syndrome criteria. The factors of MetS were standardized to obtain continuous z-scores. A battery of neuropsychological tests was used to evaluate cognitive function.

RESULTS

Higher MetS z-scores were associated with poorer global cognition using ADAS-cog (adjusted standardized beta=0.26, SE 0.11, p<0.05) and higher Trail Making B scores (adjusted beta=0.23, SE 0.11, p<0.05). Higher MetS risk was related to lower cognitive performance.

CONCLUSION

Combined risk due to multiple risk factors in MetS was related to lower global cognitive performance and executive function. A higher MetS risk burden may point to opportunities for cognitive testing in older adults as individuals may experience cognitive changes.

Improvement in verbal learning over the first year of antipsychotic treatment is associated with serum HDL levels in a cohort of first episode psychosis patients

To investigate whether changes in serum lipids are associated with cognitive performance in first episode psychosis (FEP) patients during their first year of antipsychotic drug treatment. One hundred and thirty-two antipsychotic-treated FEP patients were included through the TOP study along with 83 age- and gender-matched healthy controls (HC). Information regarding cognitive performance, psychotic symptoms, lifestyle, body mass index, serum lipids [total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein cholesterol, and triglycerides] and antipsychotic treatment was obtained at baseline and after 1 year. The cognitive test battery is comprised of assessments for verbal learning, processing speed, working memory, verbal fluency, and inhibition. Mixed-effects models were used to study the relationship between changes over time in serum lipids and cognitive domains, controlling for potential confounders. There was a significant group by HDL interaction effect for verbal learning (F = 11.12, p = 0.001), where an increase in HDL levels was associated with improvement in verbal learning in FEP patients but not in HC. Practice effects, lifestyle, and psychotic symptoms did not significantly affect this relationship. Antipsychotic-treated FEP patients who increased in HDL levels during the first year of follow-up exhibited better verbal learning capacity. Further investigations are needed to clarify the underlying mechanisms.

Metabolic Syndrome, Mild Cognitive Impairment, and Dementia: A Meta-Analysis of Longitudinal Studies

OBJECTIVE

A systematic review and a meta-analysis of both clinical and population-based studies was undertaken according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement to clarify whether Metabolic Syndrome (MetS) is a risk or a protective factor for incident dementia, Alzheimer disease (AD), and vascular dementia (VaD), and whether it's involved in progression to dementia in patients affected by mild cognitive impairment (MCI).

METHODS

Search terms included ("metabolic syndrome" OR "syndrome x" OR "plurimetabolic syndrome") AND ("dementia" OR "Alzheimer disease" OR "vascular dementia" OR "mild cognitive impairment" OR "MCI"). Research was restricted to articles published in English between January 1, 2000 and August 31, 2018. No age limit was set.

RESULTS

At the end of the selection procedure, nine longitudinal studies were selected for the meta-analysis: six studies enrolled cognitively well-functioning participants and three studies involved MCI patients. A total of 18,313 participants aged older than 40 years with mean MetS prevalence of 22.7% were followed on average for 9.41years. A fixed model was used to estimate pooled hazard ratios and 95% confidence intervals.

CONCLUSION

No statistically significant pooled association emerged between MetS and incident dementia and AD. MetS increased the incidence of pure VaD. MetS increased the risk of progression from MCI to dementia. Follow-up length might be a key factor in investigating these associations further. Because MetS is constituted by a set of potentially modifiable factors, further studies with longer follow-up and repeated assessment of both MetS and cognitive status are desirable to draw definite conclusions.

Metabolic syndrome among older adults with schizophrenia spectrum disorder: Prevalence and associated factors in a multicenter study

Metabolic syndrome and its associated morbidity and mortality have been well documented in adults with schizophrenia. However, data is lacking for their geriatric counterparts. We sought to investigate the frequency of screening and the prevalence of metabolic syndrome in older adults with schizophrenia, as well as its possible correlates, using the Cohort of individuals with schizophrenia Aged 55 years or more study (n = 353). We found that 42.2% (n = 149) of our sample was screened for metabolic syndrome. Almost half of those (n = 77; 51.7%) screened positive according to ATPIII criteria. Hypertension and abdominal obesity were the two most prevalent metabolic abnormalities. Screening was positively associated with male gender and urbanicity, and metabolic syndrome diagnosis was positively associated with cardiovascular disorders and consultation with a general practitioner (all p < 0.05). However, there were no significant associations of metabolic syndrome with socio-demographic or clinical characteristics, psychotropic medications, other medical conditions and other indicators of mental health care utilization. Our findings support that the prevalence of metabolic syndrome among older adults with schizophrenia spectrum disorder is high and screening is crucial mainly in those patients with hypertension and/or abdominal obesity. Factors at play might be different than those in the younger population.

Diabetes is Not Associated with Alzheimer's Disease Neuropathology

BACKGROUND

Previous evidence linking diabetes to Alzheimer's disease (AD) neuropathology is mixed and scant data are available from low- and middle-income countries.

OBJECTIVE

To investigate the association between diabetes and AD neuropathology in a large autopsy study of older Brazilian adults.

METHODS

In this cross-sectional study, diabetes was defined by diagnosis during life or use of antidiabetic medication. A standardized neuropathological examination was performed using immunohistochemistry. The associations of diabetes with Consortium to Establish and Registry for Alzheimer Disease (CERAD) scores for neuritic plaques and Braak-Braak (BB) scores for neurofibrillary tangles were investigated using multivariable ordinal logistic regression. We investigated effect modification of education, race, and APOE on these associations.

RESULTS

Among 1,037 subjects (mean age = 74.4±11.5 y; mean education = 4.0±3.7 y; 48% male, 61% White), diabetes was present in 279 subjects. Diabetes was not associated with BB (OR = 1.12, 95% CI = 0.81-1.54, p = 0.48) or with CERAD (OR = 0.97, 95% CI = 0.68-1.38, p = 0.86) scores on analyses adjusted for sociodemographic and clinical variables. We observed effect modification by the APOE allele ɛ4 on the association between diabetes mellitus and BB scores.

CONCLUSION

No evidence of an association between diabetes and AD neuropathology was found in a large sample of Brazilians; however, certain subgroups, such as APOE allele ɛ4 carriers, had higher odds of accumulation of neurofibrillary tangles.

Metabolic Syndrome and cognitive decline in the elderly: A systematic review

Background

Metabolic Syndrome (MetS) refers to a cluster of metabolic disturbances which is associated with increased risk for vascular and degenerative conditions in general population. Although the relationship between vascular risk factors and dementia is undisputable, additional hazard for cognitive decline in older population with concurrent metabolic disorders still waits to be demonstrated. The present review aims to analyze data on MetS and risk for cognitive decline in elderly persons.

Methods

Database searches were performed in Medline, ISI and PsycINFO for articles assessing cognitive performances of older subjects with MetS.

Results

Of a total of 505 studies, 25 were selected for the review. Risk of selection biases was identified in all the studies. Although all articles followed recognized diagnostic recommendations for MetS, minor criteria modifications were detected in most of them. Hyperglycemia was consistently associated with impaired cognitive performances in older individuals, but the role of MetS for cognitive decline and for the onset of dementia showed heterogeneous results.

Discussion

Current available data in the literature concerning the impact of MetS on the cognition of older population is inconclusive and based on inconsistent evidence. Differential effects of individual MetS components and factors associated with the age of the sample may have accounted for divergent findings among articles, but larger and higher quality studies in this field are still needed.

Association of Some Components of the Metabolic Syndrome with the Subtype of Mild Cognitive Impairment

In the last 30 years there has been a long way in what concerns the ability to test and diagnose cognitive disorders. On the other hand, it is more and more obvious the necessity to discover new parameters, which can clearly witness the passage from the physiological state of aging to a cognitive impairment in various stages (ranging from mild cognitive impairment to severe dementia). Bringing together all the clinical, paraclinical and neuropsychological data trying to discover the missing link between metabolic disorders, chronic inflammatory changes, progression of atherosclerosis, and the appearance of cognitive disorders, remains an extremely attractive and challenging field of research. By this study, we observed that there is a slight supremacy of the amnestic-MCI in patients with metabolic syndrome, without being able to extract statistically significant data. The interesting data obtained in this study emphasized the connection between the triglycerides/HDL-cholesterol ratio and the presence of the amnestic-MCI subtypes in patients with metabolic syndrome. The data obtained led to the conclusion that an increase in diastolic blood pressure in older people is a prediction factor for cognitive decline.

Hypertension, diabetes and obesity are associated with lower cognitive performance in community-dwelling elderly: Data from the FIBRA study

Background

Systemic hypertension (SH), diabetes mellitus (DM) and abdominal obesity may negatively impact cognitive performance.

Objective

To evaluate the association between SH, DM and abdominal obesity and cognitive performance among cognitively unimpaired elderly.

Methods

A cross-sectional study of individuals aged 65+ from seven Brazilian cities was conducted. SH and DM diagnoses were self-reported and abdominal circumference was objectively measured. Individuals who scored below the education-adjusted cutoff scores on the Mini-Mental State Examination (MMSE) were excluded.

Results

Among 2,593 elderly, 321 (12.38%) had SH, DM and abdominal obesity concomitantly (Group I) and 421 (16.23%) had none of the three diseases (Group II). Group I had a higher proportion of individuals that were women, aged 70-74 years, illiterate and with lower income. Group I had a higher number of participants with low cognitive performance (28.04% vs. 17.58% in Group II). Variables associated with poor cognitive performance were: female gender (OR: 2.43, p < 0.001); and lower education (OR: 0.410, p < 0.001). The presence of the three diseases and age were not significant in the education-adjusted model.

Conclusion

There was an association between cognition and the presence of SH, DM and obesity. However, education seems to be decisive in determining cognitive performance in the presence of these three conditions.

Effects of a mixed berry beverage on cognitive functions and cardiometabolic risk markers; A randomized cross-over study in healthy older adults

Background

Berries and associated bioactive compounds, e.g. polyphenols and dietary fibre (DF), may have beneficial implications with respect to the metabolic syndrome, including also cognitive functions. The aim of this study was to evaluate effects on cognitive functions and cardiometabolic risk markers of 5 wk intervention with a mixture of berries, in healthy humans.

Methods

Forty healthy subjects between 50–70 years old were provided a berry beverage based on a mixture of berries (150g blueberries, 50g blackcurrant, 50g elderberry, 50g lingonberries, 50g strawberry, and 100g tomatoes) or a control beverage, daily during 5 weeks in a randomized crossover design. The control beverage (water based) was matched with respect to monosaccharides, pH, and volume. Cognitive tests included tests of working memory capacity, selective attention, and psychomotor reaction time. Cardiometabolic test variables investigated were blood pressure, fasting blood concentrations of glucose, insulin, blood lipids, inflammatory markers, and markers of oxidative stress.

Results

The daily amounts of total polyphenols and DF from the berry beverage were 795 mg and 11g, respectively. There were no polyphenols or DF in the control beverage. The berry intervention reduced total- and LDL cholesterol compared to baseline (both P<0.05), and in comparison to the control beverage (P<0.005 and P<0.01, respectively). The control beverage increased glucose concentrations (P<0.01) and tended to increase insulin concentrations (P = 0.064) from base line, and increased insulin concentrations in comparison to the berry beverage (P<0.05). Subjects performed better in the working memory test after the berry beverage compared to after the control beverage (P<0.05). No significant effects on the other test variables were observed.

Conclusions

The improvements in cardiometabolic risk markers and cognitive performance after the berry beverage suggest preventive potential of berries with respect to type 2 diabetes, cardiovascular disease, and associated cognitive decline. Possibly the polyphenols and DF contributed to the beneficial effects.

Trial registration

ClinicalTrials.gov: NCT01562392.

Association of midlife lipids with 20-year cognitive change: A cohort study

INTRODUCTION

Existing studies predominantly consider the association of late-life lipid levels and subsequent cognitive change. However, midlife rather than late-life risk factors are often most relevant to cognitive health.

METHODS

We quantified the association between measured serum lipids in midlife and subsequent 20-year change in performance on three cognitive tests in 13,997 participants of the Atherosclerosis Risk in Communities study.

RESULTS

Elevated total cholesterol, low-density lipoprotein cholesterol, and triglycerides were associated with greater 20-year decline on a test of executive function, sustained attention, and processing speed. Higher total cholesterol and triglycerides were also associated with greater 20-year decline in memory scores and a measure summarizing performance on all three tests. High-density lipoprotein cholesterol was not associated with cognitive change. Results were materially unchanged in sensitivity analyses addressing informative missingness.

DISCUSSION

Elevated total cholesterol, low-density lipoprotein cholesterol, and triglycerides in midlife were associated with greater 20-year cognitive decline.

Neuropsychological functioning, age, and medication adherence in bipolar disorder

Objectives

Poor adherence to medication is frequent in bipolar disorder (BD) and has been associated with several factors. To date, the relationship between low adherence and neuropsychological functioning in BD is still unclear. As age and neuropsychological functioning might have opposing influences on adherence, our aim was to investigate this link with a particular focus on the effect of age.

Methods

In a cross-sectional study, we included 353 patients divided into two age-groups (16–46; 47–71) from a French cohort diagnosed with BD (type I, II, NOS) and strictly euthymic. All patients had a standardized clinical and neuropsychological assessment and were categorized as high (n = 186) or low (n = 167) adherent based on their score from the Medication Adherence Rating Scale. Clinical information was collected based on a standardized interview and clinical validated scales. Neuropsychological performances were evaluated with an established standardized neuropsychological battery for bipolar disorder patients. After univariate analysis, neuropsychological and clinical predictors of low adherence were included in two age-specific stepwise multiple logistic regressions.

Results

A smaller number of hospitalizations (OR = 0.846, p = 0.012), a shorter illness duration (OR = 0.937, p = 0.003) and higher adverse effects (OR = 1.082, p<0.001) were associated with a greater risk of low adherence in the younger patients. In the older patients, low adherence was also predicted by a smaller number of hospitalizations (OR = 0.727, p = 0.008) and higher adverse effects (OR = 1.124, p = 0.005). Interestingly poor inhibition performance was also a significant predictor of low adherence in older patients (OR = 0.924, p = 0.030).

Conclusions

We found an age-specific relationship between cognitive functioning and adherence in patients with BD. Poor inhibition performances predicted low adherence in older patients only. Our results highlight the need to provide age-adapted therapeutic interventions to improve adherence in patients with BD.

Functional magnetic resonance imaging response as an early biomarker of cognitive decline in elderly patients with metabolic syndrome

OBJECTIVES

We assessed whether potential changes in brain activation patterns of elderly individuals with metabolic syndrome (MetS) who were cognitively healthy (without mild cognitive impairment or dementia) were associated with cognitive decline in executive function in the short-term.

METHOD

We analyzed 43 individuals (23 MetS, 20 controls) using a global geriatric evaluation, a neuropsychological battery, and task-related (attention) fMRI exam. Correlation analysis between the fMRI signal at baseline and cognitive impairment after 1year was based on the voxel-based Pearson coefficient, corrected for multiple comparisons.

RESULTS

At baseline, MetS patients showed reduced brain response in frontal and parietal regions compared to controls. After one year, the MetS group also showed a decline in verbal fluency performance. fMRI response in the right dorsolateral prefrontal cortex and bilateral parietal lobes was negatively correlated with verbal fluency decline in the MetS group.

DISCUSSION

Our results provide an early biomarker of the possible development of cognitive impairment, particularly in the executive function, of elderly individuals suffering from MetS. These findings also point to an up or down regulation which could be interpreted as compensatory mechanism for possible brain tissue burden caused by MetS.

Metabolic adverse effects of olanzapine on cognitive dysfunction: A possible relationship between BDNF and TNF-alpha

OBJECTIVE

There is accumulating evidence indicating that long-term treatment with second-generation antipsychotics (SGAs) results in metabolic syndrome (MetS) and cognitive impairment. This evidence suggests an intrinsic link between antipsychotic-induced MetS and cognitive dysfunction in schizophrenia patients. Olanzapine is a commonly prescribed SGA with a significantly higher MetS risk than that of most antipsychotics. In this study, we hypothesized that olanzapine-induced MetS may exacerbate cognitive dysfunction in patients with schizophrenia.

METHODS

A sample of 216 schizophrenia patients receiving long-term olanzapine monotherapy were divided into two groups, MetS and non-MetS, based on the diagnostic criteria of the National Cholesterol Education Program's Adult Treatment Panel III. We also recruited 72 healthy individuals for a control group. Cognitive function was evaluated using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Plasma brain-derived neurotrophic factor (BDNF) and tumor necrosis factor-alpha (TNF-alpha) were measured by an enzyme-linked immunosorbent assay for 108 patients and 47 controls.

RESULTS

Among the 216 schizophrenia patients receiving olanzapine monotherapy, MetS was found in 95/216 (44%). Patients with MetS had more negative symptoms, higher total scores in PANSS (Ps<0.05) and lower immediate memory, attention, delayed memory and total scores in RBANS (Ps<0.01). Stepwise multivariate linear regression analysis revealed that increased glucose was the independent risk factor for cognitive dysfunction (t=-2.57, P=0.01). Patients with MetS had significantly lower BDNF (F=6.49, P=0.012) and higher TNF-alpha (F=5.08, P=0.026) levels than those without MetS. There was a negative correlation between the BDNF and TNF-alpha levels in the patients (r=-0.196, P=0.042).

CONCLUSION

Our findings provide evidence suggesting that the metabolic adverse effects of olanzapine may aggravate cognitive dysfunction in patients with schizophrenia through an interaction between BDNF and TNF-alpha.

Glycemia but not the Metabolic Syndrome is Associated with Cognitive Decline: Findings from the European Male Ageing Study

OBJECTIVE

Previous research has indicated that components of the metabolic syndrome (MetS), such as hyperglycemia and hypertension, are negatively associated with cognition. However, evidence that MetS itself is related to cognitive performance has been inconsistent. This longitudinal study investigates whether MetS or its components affect cognitive decline in aging men and whether any interaction with inflammation exists.

METHODS

Over a mean of 4.4 years (SD ± 0.3), men aged 40-79 years from the multicenter European Male Ageing Study were recruited. Cognitive functioning was assessed using the Rey-Osterrieth Complex Figure (ROCF), the Camden Topographical Recognition Memory (CTRM) task, and the Digit Symbol Substitution Test (DSST). High-sensitivity C-reactive protein (hs-CRP) levels were measured using a chemiluminescent immunometric assay.

RESULTS

Overall, 1,913 participants contributed data to the ROCF analyses and 1,965 subjects contributed to the CTRM and DSST analyses. In multiple regression models the presence of baseline MetS was not associated with cognitive decline over time (p > 0.05). However, logistic ordinal regressions indicated that high glucose levels were related to a greater risk of decline on the ROCF Copy (β = -0.42, p < 0.05) and the DSST (β = -0.39, p < 0.001). There was neither a main effect of hs-CRP levels nor an interaction effect of hs-CRP and MetS at baseline on cognitive decline.

CONCLUSION

No evidence was found for a relationship between MetS or inflammation and cognitive decline in this sample of aging men. However, glycemia was negatively associated with visuoconstructional abilities and processing speed.

The emerging link between O-GlcNAcylation and neurological disorders

O-linked β-N-acetylglucosaminylation (O-GlcNAcylation) is involved in the regulation of many cellular cascades and neurological diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), and stroke. In the brain, the expression of O-GlcNAcylation is notably heightened, as is that of O-linked N-acetylglucosaminyltransferase (OGT) and β-N-acetylglucosaminidase (OGA), the presence of which is prominent in many regions of neurological importance. Most importantly, O-GlcNAcylation is believed to contribute to the normal functioning of neurons; conversely, its dysregulation participates in the pathogenesis of neurological disorders. In neurodegenerative diseases, O-GlcNAcylation of the brain's key proteins, such as tau and amyloid-β, interacts with their phosphorylation, thereby triggering the formation of neurofibrillary tangles and amyloid plaques. An increase of O-GlcNAcylation by pharmacological intervention prevents neuronal loss. Additionally, O-GlcNAcylation is stress sensitive, and its elevation is cytoprotective. Increased O-GlcNAcylation ameliorated brain damage in victims of both trauma-hemorrhage and stroke. In this review, we summarize the current understanding of O-GlcNAcylation's physiological and pathological roles in the nervous system and provide a foundation for development of a therapeutic strategy for neurological disorders.

Cognitive decline in metabolic syndrome is linked to microstructural white matter abnormalities

Subjects with metabolic syndrome (MetS) often show worse cognitive performance compared with the healthy population. We investigated whether microstructural white matter abnormalities are associated with cognitive performance in adults with MetS using diffusion tensor MR imaging. A total of 32 subjects with MetS (age 64.8 ± 7.8, 56.25 % female) and 23 age-, gender-, and education-matched healthy controls completed a battery of neuropsychological tests and diffusion tensor imaging (DTI) at 3-T MRI. Brain global and regional volumes, white matter fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (LD) were calculated. The least-square models adjusted for age, sex, HbA1c, hypertension, body mass index, hyperlipidemia, and white matter hyperintensities were used to evaluate the relationship between cognitive function and DTI. The MetS group had worse performance in verbal fluency (VF) and learning and memory function (total VF: T score (p = 0.01), VF: animals T score (p = 0.0001), Hopkins Verbal Learning Test (HVLT): Total recall T score (p = 0.0001), and HVLT: delayed recall T score (p = 0.002), as compared with controls. In the MetS group, abnormalities in diffusivity measures were associated with worse cognitive performance [VF: animals T score and left post-central gyrus-LD (p = 0.0007, r _adj 0.4), R angular gyrus-RD (p = 0.0008, r _adj 0.3), L supra-marginal gyrus-RD (p = 0.009, r _adj 0.2) after adjusting for age, sex, HbA1c, 24 h mean BP, presence of hyperlipidemia, and global white matter hyperintensities]. Microstructural white matter abnormalities in the MetS group might be the underlying mechanisms of worse verbal learning and memory performance.

Predictive Factors for Verbal Memory Performance Over Decades of Aging: Data from the Women's Healthy Ageing Project

BACKGROUND

Abnormalities in brain structure and function can occur several decades prior to the onset of cognitive decline. It is in the preceding decades that an intervention is most likely to be effective, when informed by an understanding of factors contributing to the disease prodrome. Few studies, however, have sufficient longitudinal data on relevant risks to determine the optimum targets for interventions to improve cognition in aging. In this article we examine the timing and exposure of factors contributing to verbal memory performance in later life.

METHODS

387 participants from the population-based Women's Healthy Ageing Project, mean age at baseline of 49.6 years (range: 45-55 years), had complete neuropsychiatric assessments, clinical information, physical measures, and biomarkers collected at baseline, with at least three follow-up visits that included at least one cognitive reassessment. Mixed linear models were conducted to assess the significance of risk factors on later-life verbal memory. We explored the influence of early, contemporaneous, and cumulative exposures.

RESULTS

Younger age and better education were associated with baseline memory test performance (CERAD). Over the 20 years of study follow-up, cumulative mid- to late-life physical activity had the strongest effect on better later life verbal memory (0.136 [0.058, 0.214]). The next most likely contributors to verbal memory in late life were the negative effect of cumulative hypertension (-0.033 [-0.047, -0.0.18] and the beneficial effect of HDL cholesterol (0.818 [0.042, 1.593]).

CONCLUSIONS

Findings suggest that midlife interventions focused on physical activity, hypertension control, and achieving optimal levels of HDL cholesterol will help maintain later-life verbal memory skills.

Cognitive disorders in diabetic patients

This chapter gives an overview of the literature on cognitive dysfunction in adults with type 1 or type 2 diabetes. First, methods to evaluate cognitive functioning and the pattern and severity of cognitive dysfunction in relation to diabetes will be discussed. The reader will note that diabetes is associated with worse cognitive functioning and an increased dementia risk. Next, diabetes-associated abnormalities on brain MRI, including reductions in brain volume - i.e., cerebral atrophy - and vascular lesions, will be addressed. At the group level there are clear relations between these imaging abnormalities and cognitive dysfunction, but at the level of the individual patient these relations are often less clear. Subsequently, risk factors for cognitive performance will be discussed. Evidently, these risk factors are related to diabetes type and the age of the patients involved. For type 1 diabetes, an early age at diabetes onset is the most consistent risk factor, whereas in type 2 diabetes, vascular risk factors and vascular comorbidities are consistent indicators of increased risk. The final section of the chapter addresses possible preventive and treatment measures and implications for daily care.

Prevention of Age-Related Cognitive Decline: Which Strategies, When, and for Whom?

Brain aging is characterized by the progressive and gradual accumulation of detrimental changes in structure and function, which increase risk of age-related cognitive decline and dementia. This devastating chronic condition generates a huge social and economic burden and accounts for 11.2% of years of disability. The increase in lifespan has contributed to the increase in dementia prevalence; however, there is currently no curative treatment for most causes of dementias. This paper reviews evidence-based strategies to build, enhance, and preserve cognition over the lifespan by examining approaches that work best, proposing when in the life course they should be implemented, and in which population group(s). Recent work shows a tendency to decreased age-specific prevalence and incidence of cognitive problems and dementia among people born later in the first half of the 20th century, citing higher educational levels, improvements in lifestyle, and better handling of vascular risk factors. This implies that we can target modifiable environmental, lifestyle, and health risk factors to modify the trajectory of cognitive decline before the onset of irreversible dementia. Because building cognitive reserve and prevention of cognitive decline are of critical importance, interventions are needed at every stage of the life course to foster cognitive stimulation, and enable healthy eating habits and physical activity throughout the lifespan. Preventive interventions to decrease and delay cognitive decline and its consequences in old age will also require collaboration and action on the part of policy-makers at the political and social level.