A major role for cardiovascular burden in age-related cognitive decline

The lifestyle for brain health index, the cluster of differentiation 33 (CD33) gene, and cognitive function among rural Chinese older adults: A population-based study

BACKGROUND

We sought to examine the associations of the Lifestyle for Brain Health (LIBRA) index with cognitive function among rural Chinese older adults and to explore the potential role of cluster of differentiation 33 gene (CD33) in the associations.

METHODS

This population-based cross-sectional study included 4914 dementia-free participants (age ≥60 years; 56.43 % women) in the 2018 baseline examination of MIND-China. The LIBRA index was generated from 11 factors. We used a neuropsychological test battery to assess episodic memory, verbal fluency, attention, executive function, and global cognition. The CD33(rs3865444) polymorphism was detected using multiple-polymerase chain reaction amplification. Data were analyzed using the general linear regression models.

RESULTS

A higher LIBRA index was associated with multivariable-adjusted β-coefficient (95 %CI) of -0.011(-0.020- -0.001) for global cognitive z-score, -0.020(-0.033- -0.006) for episodic memory, and -0.016(-0.029- -0.004) for verbal fluency. The CD33(rs3865444) was associated with a lower global cognitive z-score in the additive (CA vs. CC: β-coefficient=0.042; 95 %CI=0.008-0.077), the dominant (CA+AA vs. CC: 0.040; 0.007-0.073), and the over-dominant (CA vs. CC+AA: 0.043; 0.009-0.077) models. Similar results were obtained for verbal fluency and attention. The CD33 gene showed statistical interactions with LIBRA index on cognitive function (Pinteraction<0.05) such that a higher LIBRA index was significantly associated with lower z-scores of global cognition and attention only among CD33 CC carriers (P < 0.05).

CONCLUSIONS

This population-based study reveals for the first time that a higher LIBRA index is associated with worse cognitive performance in rural Chinese older adults and that CD33 gene could modify the association.

Association of midlife air pollution exposures and residential road proximity with incident dementia: The Atherosclerosis Risk in Communities (ARIC) study

BACKGROUND

Increasing evidence links higher air pollution exposures to increased risk of cognitive impairment. While midlife risk factors are often most strongly linked to dementia risk, few studies have considered associations between midlife roadway proximity or ambient air pollution exposure and incident dementia decades later, in late life.

OBJECTIVES

Our objective was to determine if midlife exposures to ambient air pollution or roadway proximity are associated with increased risk of dementia in the Atherosclerosis Risk in Communities (ARIC) study over up to 29 years of follow-up.

METHODS

Our eligible sample included Black and White ARIC participants without dementia at Visit 2 (1990-1992). Participants were followed through Visit 7 (2018-2019), with dementia status and onset date defined based on formal dementia ascertainment at study visits, informant interviews, and surveillance efforts. We used adjusted Weibull survival models to assess the associations of midlife ambient air pollution and road proximity with incident dementia.

RESULTS

The median age at baseline (1990-1992, Visit 2) of the 12,700 eligible ARIC participants was 57.0 years; 56.0% were female, 24.2% were Black, and 78.9% had at least a high school education. Over up to 29 years of follow-up, 2511 (19.8%) persons developed dementia. No associations were found between ambient air pollutants and proximity to major roadways with risk of incident dementia. In exploratory analyses, living closer to roadways in midlife increased dementia risk in individuals younger at baseline and those without midlife hypertension, and there was evidence of increased risk of dementia with increased midlife exposure to NOx, several PM2.5 components, and trace metals among those with diabetes in midlife.

CONCLUSIONS

Midlife exposure to ambient air pollution and midlife roadway proximity was not associated with dementia risk over decades of follow-up. Further investigation to explore potential for greater susceptibility among specific subgroups identified here is needed.

Anti-Inflammatory Diet and Dementia in Older Adults With Cardiometabolic Diseases

Importance

Inflammation has been proposed as a mechanism linking cardiometabolic diseases (CMDs) to increased risk of dementia. However, whether an anti-inflammatory diet can support brain and cognitive health among people with CMDs is unclear.

Objective

To examine CMD status and dietary inflammatory potential in association with dementia risk and brain magnetic resonance imaging (MRI) measures using joint effect analysis.

Design, Setting, and Participants

The UK Biobank is an ongoing community-based cohort study with baseline assessments conducted between March 13, 2006, and October 1, 2010. The present study included 84 342 dementia-free older adults (≥60 years), who were followed up until January 20, 2022 (maximum, 15 years). A subsample (n = 8917) underwent brain MRI scans between May 2, 2014, and March 13, 2020.

Exposures

Baseline CMDs (including type 2 diabetes, heart disease, and stroke) were ascertained from medical records. Dietary Inflammatory Index scores (anti-inflammatory [≤-1.5 points], neutral [>-1.5 to <0.5 points], or proinflammatory [≥0.5 points]) were calculated from participants' average intake of 31 nutrients, assessed up to 5 times using the Oxford WebQ, a web-based, 24-hour dietary assessment.

Main Outcomes and Measures

Incident dementia was identified through linkage to medical records. Regional brain volumes were collected from brain MRI scans.

Results

The study included 84 342 participants (mean [SD] age, 64.1 [2.9] years; 43 220 [51.2%] female). At baseline, 14 079 (16.7%) had at least 1 CMD. Over a median follow-up of 12.4 (IQR, 11.8-13.1) years, 1559 individuals (1.9%) developed dementia. With the use of joint effect analysis, the hazard ratio of dementia was 2.38 (95% CI, 1.93-2.93) for people with CMDs and a proinflammatory diet and 1.65 (95% CI, 1.36-2.00) for those with CMDs and an anti-inflammatory diet (reference: CMD-free, anti-inflammatory diet). Dementia risk was 31% lower (hazard ratio, 0.69; 95% CI, 0.55-0.88; P = .003) among people with CMDs and an anti-inflammatory diet. On brain MRI, participants with CMDs and an anti-inflammatory diet compared with a proinflammatory diet additionally had significantly larger gray matter volume (β = -0.15; 95% CI, -0.24 to -0.06 vs β = -0.27; 95% CI, -0.38 to -0.16) and smaller white matter hyperintensity volume (β = 0.05; 95% CI, -0.04 to 0.14 vs β = 0.16; 95% CI, 0.05-0.27).

Conclusions and Relevance

In this cohort study, people with CMDs and an anti-inflammatory compared with proinflammatory diet had a significantly lower hazard ratio of dementia, larger gray matter volume, and smaller white matter hyperintensity volume.

The association of pre-cancer diagnosis cardiovascular risk factors with memory aging after a cancer diagnosis, overall and by race/ethnicity

PURPOSE

Cardiovascular risk factors (CVRFs) are associated with increased risk for cognitive impairment and decline in the general population, but less is known about how CVRFs might influence cognitive aging among older cancer survivors. We aimed to determine how CVRFs prior to a cancer diagnosis affect post-cancer diagnosis memory aging, compared to cancer-free adults, and by race/ethnicity.

METHODS

Incident cancer diagnoses and memory (immediate and delayed recall) were assessed biennially in the US Health and Retirement Study (N = 5,736, 1998-2018). CVRFs measured at the wave prior to a cancer diagnosis included self-reported cigarette smoking, obesity, diabetes, heart disease, hypertension, and stroke. Multivariable-adjusted linear mixed-effects models evaluated the rate of change in standardized memory score (SD/decade) post-cancer diagnosis for those with no, medium, and high CVRFs, compared to matched cancer-free adults, overall and stratified by sex and race/ethnicity.

RESULTS

Higher number of CVRFs was associated with worse baseline memory for both men and women, regardless of cancer status. Cancer survivors with medium CVRFs had slightly slower rates of memory decline over time relative to cancer-free participants (0.04 SD units/decade [95% CI: 0.001, 0.08]). Non-Hispanic Black (NHB) and Hispanic cancer-free participants and cancer survivors had worse baseline memory than their Non-Hispanic White (NHW) counterparts.

CONCLUSIONS

CVRFs were associated with worse baseline memory function, but not decline, for cancer-free adults and cancer survivors. Racial disparities were largely similar between cancer survivors and cancer-free adults.

IMPLICATIONS FOR CANCER SURVIVORS

These findings may inform hypotheses about pre-diagnosis multimorbidity and cognitive aging of cancer survivors from diverse groups.

Malignant left ventricular hypertrophy and risk of cognitive impairment in SPRINT MIND trial

BACKGROUND

The association of malignant left ventricular hypertrophy (LVH), a specific subphenotype of LVH characterized by elevated levels of high-sensitivity cardiac troponin (hs-cTnT) or N-terminal pro-B-type natriuretic peptide (NT-proBNP), with cognitive decline remains understudied.

METHODS

This post-hoc analysis included a total of 8,027 (67.9 ± 9.3 years) SPRINT MIND trial participants who had with at least 1 follow-up cognitive assessment. Participants were classified into 6 groups on the basis of LVH status on electrocardiogram (ECG), and elevations in levels of hs-cTnT ≥14 ng/L or NT-proBNP ≥125 pg/mL at baseline visit. Multivariate Cox proportional hazard models were used to examine the association of LVH/biomarker groups with incident probable dementia, mild cognitive impairment (MCI) and a composite of MCI/probable dementia.

RESULTS

Over a median follow-up period of 5 years, there were 306, 597, and 818 incidents of MCI, probable dementia and a composite of MCI/probable dementia, respectively. Compared with participants without LVH and normal biomarker levels, those with concomitant LVH and elevated levels of both biomarkers were associated with a higher risk of probable dementia (HR, 2.50; 95% CI (1.26-4.95), MCI (HR, 1.78; 95% CI (0.99-3.23) and the composite of MCI/ probable dementia (HR, 1.89; 95% CI, 1.16-3.10).

CONCLUSIONS

Among SPRINT participants, malignant LVH is associated with incident probable dementia and mild cognitive impairment. These findings underscore the potential utility of measuring hs-cTnT and NT-proBNP levels when LVH is detected on ECG, aiding in the differentiation of individuals with a favorable risk for cognitive impairment from those with a higher risk.

Association of Cardiovascular Health With Brain Age Estimated Using Machine Learning Methods in Middle-Aged and Older Adults

BACKGROUND AND OBJECTIVES

Cardiovascular health (CVH) has been associated with cognitive decline and dementia, but the extent to which CVH affects brain health remains unclear. We investigated the association of CVH, assessed using Life's Essential 8 (LE8), with neuroimaging-based brain age and brain-predicted age difference (brain-PAD).

METHODS

This longitudinal community-based study was based on UK Biobank participants aged 40-69 years who were free from dementia and other neurologic diseases at baseline. LE8 score at baseline was assessed with 8 measures and tertiled as low, moderate, and high CVH. Structural and functional brain MRI scans were performed approximately 9 years after baseline, and 1,079 measures from 6 neuroimaging modalities were used to model brain age. A Least Absolute Shrinkage and Selection Operator regression model was trained in 4,355 healthy participants and then used to calculate brain age and brain-PAD in the whole population. Data were analyzed using linear regression models.

RESULTS

The study included 32,646 participants (mean age at baseline 54.74 years; 53.44% female; mean LE8 score: 71.90). In multivariable-adjusted linear regression, higher LE8 score was associated with younger brain age (β [95% CI] -0.037 [-0.043 to -0.031]) and more negative brain-PAD (β [95% CI] -0.043 [-0.048 to -0.038]) (brain looks younger for chronological age). Compared with high CVH, low/moderate CVH was associated with older brain age (β [95% CI] 1.030 [0.852-1.208]/0.475 [0.303-0.647]) and increased brain-PAD (β [95% CI] 1.193 [1.029-1.357]/0.528 [0.370-0.686]). The associations between low CVH and older brain age/brain-PAD remained similar and significant in both middle-aged (β [95% CI] 1.199 [0.992-1.405]/1.351 [1.159-1.542]) and older adults (β [95% CI] 0.764 [0.417-1.110]/0.948 [0.632-1.263]).

DISCUSSION

Low CVH is associated with older brain age and greater brain-PAD, even among middle-aged adults. Our findings suggest that optimizing CVH could support brain health. The main limitation of our study is that the study sample was healthier than the general population, thus caution is required when generalizing our findings to other populations.

Essential New Complexity-Based Themes for Patient-Centered Diagnosis and Treatment of Dementia and Predementia in Older People: Multimorbidity and Multilevel Phenomenology

Dementia is a highly prevalent condition with devastating clinical and socioeconomic sequela. It is expected to triple in prevalence by 2050. No treatment is currently known to be effective. Symptomatic late-onset dementia and predementia (SLODP) affects 95% of patients with the syndrome. In contrast to trials of pharmacological prevention, no treatment is suggested to remediate or cure these symptomatic patients. SLODP but not young onset dementia is intensely associated with multimorbidity (MUM), including brain-perturbating conditions (BPCs). Recent studies showed that MUM/BPCs have a major role in the pathogenesis of SLODP. Fortunately, most MUM/BPCs are medically treatable, and thus, their treatment may modify and improve SLODP, relieving suffering and reducing its clinical and socioeconomic threats. Regrettably, the complex system features of SLODP impede the diagnosis and treatment of the potentially remediable conditions (PRCs) associated with them, mainly due to failure of pattern recognition and a flawed diagnostic workup. We suggest incorporating two SLODP-specific conceptual themes into the diagnostic workup: MUM/BPC and multilevel phenomenological themes. By doing so, we were able to improve the diagnostic accuracy of SLODP components and optimize detecting and favorably treating PRCs. These revolutionary concepts and their implications for remediability and other parameters are discussed in the paper.

Cardiometabolic multimorbidity, peripheral biomarkers, and dementia in rural older adults: The MIND-China study

INTRODUCTION

Evidence has emerged that cardiometabolic multimorbidity (CMM) is associated with dementia, but the underlying mechanisms are poorly understood.

METHODS

This population-based study included 5704 older adults. Of these, data were available in 1439 persons for plasma amyloid-β (Aβ), total tau, and neurofilament light chain (NfL) and in 1809 persons for serum cytokines. We defined CMM following two common definitions used in previous studies. Data were analyzed using general linear, logistic, and mediation models.

RESULTS

The presence of CMM was significantly associated with an increased likelihood of dementia, Alzheimer's disease (AD), and vascular dementia (VaD) (p < 0.05). CMM was significantly associated with increased plasma Aβ40, Aβ42, and NfL, whereas CMM that included visceral obesity was associated with increased serum cytokines. The mediation analysis suggested that plasma NfL significantly mediated the association of CMM with AD.

DISCUSSION

CMM is associated with dementia, AD, and VaD in older adults. The neurodegenerative pathway is involved in the association of CMM with AD.

HIGHLIGHTS

The presence of CMM was associated with increased likelihoods of dementia, AD, and VaD in older adults. CMM was associated with increased AD-related plasma biomarkers and serum inflammatory cytokines. Neurodegenerative pathway was partly involved in the association of CMM with AD.

Association of solid fuel use with cognitive function and the modifying role of lifestyle: A nationwide cohort study in China

BACKGROUND

As opposed to a healthy lifestyle, indoor air pollution from solid fuel use may be harmful for cognitive function. However, the extent to which lifestyle modifies the association between solid fuel use and cognitive function remains unknown.

METHODS

A total of 21,008 individuals aged 16 to 92 were enrolled in 2010 and followed up to 2014 in the China Family Panel Studies (CFPS). Cognitive function was assessed using standardized math and word tests in two waves. Solid fuel use at baseline was assessed by self-reporting of firewood, straw, or coal used for cooking. Lifestyle profile was classified into two groups (favorable vs. unfavorable) based on five modifiable lifestyle factors including alcohol drinking, smoking, body mass index, diet, and physical activity. Linear mixed-effects models were employed to assess the association of solid fuel use and lifestyle with cognitive function. The effect modification of lifestyle was analyzed.

RESULTS

A total of 49.7% of the study population used solid fuels for cooking and 17.4% had a favorable lifestyle. Solid fuel use was associated with a significant decrease in cognitive function (β = -0.29, 95% CI: -0.39, -0.19 for math test; β = -0.62, 95% CI: -0.84, -0.41 for word test). Lifestyle significantly modified this association (p-interaction: 0.006 for math test; 0.016 for word test), with the corresponding association being less pronounced among participants adhering to a favorable lifestyle compared to those with an unfavorable lifestyle.

CONCLUSION

A favorable lifestyle may attenuate the adverse association between solid fuel use and cognitive function. Adopting a favorable lifestyle has the potential to mitigate the adverse neurological effects due to indoor air pollution.

Prolonged ventricular repolarization associated with mild cognitive impairment and white matter hyperintensities: a cross-sectional study

Prolonged ventricular repolarization has been associated with cardiovascular disease. We sought to investigate the association of prolonged ventricular repolarization with mild cognitive impairment (MCI) and the potential underlying neuropathological mechanisms in older adults. This cross-sectional study included 4328 dementia-free participants (age ≥ 65 years; 56.8% female) in the baseline examination of the Multidomain INterventions to delay dementia and Disability in rural China; of these, 989 undertook structural brain magnetic resonance imaging (MRI) scans. QT, QTc, JT, JTc, and QRS intervals were derived from 12-lead electrocardiograph. MCI, amnestic MCI (aMCI), and non-amnestic MCI (naMCI) were defined following the Petersen's criteria. Volumes of gray matter (GM), white matter, cerebrospinal fluid, total white matter hyperintensities (WMH), periventricular WMH (PWMH), and deep WMH (DWMH) were automatically estimated. Data were analyzed using logistic and general linear regression models. Prolonged QT, QTc, JT, and JTc intervals were significantly associated with an increased likelihood of MCI and aMCI, but not naMCI (p < 0.05). In the MRI subsample, QT, QTc, JT, and JTc intervals were significantly associated with larger total WMH and PWMH volumes (p < 0.05), but not with DWMH volume. Statistical interactions were detected, such that prolonged QT and JT intervals were significantly associated with reduced GM volume only among participants with coronary heart disease or without APOE ε4 allele (p < 0.05). Prolonged ventricular repolarization is associated with MCI and cerebral microvascular lesions in a general population of older adults. This underlies the importance of cognitive assessments and brain MRI examination among older adults with prolonged QT interval.

Association of cardiovascular diseases with cognitive performance in older adults

BACKGROUND

Cognitive function and cardiovascular disease (CVD) have a bidirectional relationship, but studies on the impact of CVD subtypes and aging spectrum have been scarce.

METHODS

We assessed older adults aged ≥60 years from the 2011 to 2012 and 2013 to 2014 cycles of the National Health and Nutrition Examination Survey who had coronary heart disease, angina, prior myocardial infarction, congestive heart failure, or prior stroke. We compared CERAD-IR, CERAD-DR, Animal Fluency test, and DSST scores to assess cognitive performance in older adults with and without CVD.

RESULTS

We included 3,131 older adults, representing 55,479,673 older adults at the national level. Older adults with CVD had lower CERAD-IR (mean difference 1.8, 95% CI 1.4-2.1, P < .001), CERAD-DR (mean difference 0.8, 95% CI 0.6-1.0, P < .001), Animal Fluency test (mean difference 2.1, 95% CI 1.6-2.6, P < .001), and DSST (mean difference 9.5, 95% CI 8.0-10.9, P < .001) scores compared with those without CVD. After adjustment, no difference in CERAD-IR, CERAD-DR, and Animal Fluency test scores was observed, but DSST scores were lower in older adults with CVD (adjusted mean difference 2.9, 95% CI 1.1-4.7, P = .001). Across CVD subtypes, individuals with congestive heart failure had lower performance on the DSST score. The oldest-old cohort of patients ≥80 years old with CVD had lower performance than those without CVD on both the DSST and Animal Fluency test.

CONCLUSION

Older adults with CVD had lower cognitive performance as measured than those free of CVD, driven by pronounced differences among those with CHF and those ≥80 years old with CVD.

Blood biomarkers of Alzheimer's disease in the community: Variation by chronic diseases and inflammatory status

INTRODUCTION

We explored the variations of blood biomarkers of Alzheimer's disease (AD) by chronic diseases and systemic inflammation.

METHODS

We explored the association of AD blood biomarkers with chronic diseases and systemic inflammation (interleukin-6 [IL-6]), in 2366 dementia-free participants of the Swedish National Study on Aging and Care-in Kungsholmen, using quantile regression models.

RESULTS

A greater number of co-occurring chronic diseases was associated with higher concentrations of phosphorylated-tau 181 (p-tau181), total-tau (t-tau), neurofilament light chain (NfL), and glial fibrillary acidic protein (GFAP) (p < 0.01). Anemia, kidney, cerebrovascular, and heart diseases were associated with variations in the levels of AD blood biomarkers. Participants in the highest (vs. lowest) interleukin-6 (IL-6) tertile had higher NfL concentration. Systemic inflammation amplified the associations between several chronic diseases and p-tau181, t-tau, NfL, and GFAP.

DISCUSSION

In the community, the concentration of AD blood biomarkers varies in relation to medical conditions and systemic inflammation. Recognizing these influences is crucial for the accurate interpretation and clinical implementation of blood biomarkers.

HIGHLIGHTS

Participants with a complex clinical profile (i.e., multiple co-occurring diseases or specific disease combinations) display elevated levels of AD blood-biomarkers. Anemia, heart, cerebrovascular, and kidney diseases are associated with variations is the levels of AD blood biomarkers in cognitively intact older adults. Systemic inflammation amplifies the association between several chronic diseases and AD blood biomarkers.

Identifying dementia from cognitive footprints in hospital records among Chinese older adults: a machine-learning study

Background

By combining theory-driven and data-driven methods, this study aimed to develop dementia predictive algorithms among Chinese older adults guided by the cognitive footprint theory.

Methods

Electronic medical records from the Clinical Data Analysis and Reporting System in Hong Kong were employed. We included patients with dementia diagnosed at 65+ between 2010 and 2018, and 1:1 matched dementia-free controls. We identified 51 features, comprising exposures to established modifiable factors and other factors before and after 65 years old. The performances of four machine learning models, including LASSO, Multilayer perceptron (MLP), XGBoost, and LightGBM, were compared with logistic regression models, for all patients and subgroups by age.

Findings

A total of 159,920 individuals (40.5% male; mean age [SD]: 83.97 [7.38]) were included. Compared with the model included established modifiable factors only (area under the curve [AUC] 0.689, 95% CI [0.684, 0.694]), the predictive accuracy substantially improved for models with all factors (0.774, [0.770, 0.778]). Machine learning and logistic regression models performed similarly, with AUC ranged between 0.773 (0.768, 0.777) for LASSO and 0.780 (0.776, 0.784) for MLP. Antipsychotics, education, antidepressants, head injury, and stroke were identified as the most important predictors in the total sample. Age-specific models identified different important features, with cardiovascular and infectious diseases becoming prominent in older ages.

Interpretation

The models showed satisfactory performances in identifying dementia. These algorithms can be used in clinical practice to assist decision making and allow timely interventions cost-effectively.

Funding

The Research Grants Council of Hong Kong under the Early Career Scheme 27110519.

Joint effects of air pollution and neighborhood socioeconomic status on cognitive decline - Mediation by depression, high cholesterol levels, and high blood pressure

Air pollution and neighborhood socioeconomic status (N-SES) are associated with adverse cardiovascular health and neuropsychiatric functioning in older adults. This study examines the degree to which the joint effects of air pollution and N-SES on the cognitive decline are mediated by high cholesterol levels, high blood pressure (HBP), and depression. In the Emory Healthy Aging Study, 14,390 participants aged 50+ years from Metro Atlanta, GA, were assessed for subjective cognitive decline using the cognitive function instrument (CFI). Information on the prior diagnosis of high cholesterol, HBP, and depression was collected through the Health History Questionnaire. Participants' census tracts were assigned 3-year average concentrations of 12 air pollutants and 16 N-SES characteristics. We used the unsupervised clustering algorithm Self-Organizing Maps (SOM) to create 6 exposure clusters based on the joint distribution of air pollution and N-SES in each census tract. Linear regression analysis was used to estimate the effects of the SOM cluster indicator on CFI, adjusting for age, race/ethnicity, education, and neighborhood residential stability. The proportion of the association mediated by high cholesterol levels, HBP, and depression was calculated by comparing the total and direct effects of SOM clusters on CFI. Depression mediated up to 87 % of the association between SOM clusters and CFI. For example, participants living in the high N-SES and high air pollution cluster had CFI scores 0.05 (95 %-CI:0.01,0.09) points higher on average compared to those from the high N-SES and low air pollution cluster; after adjusting for depression, this association was attenuated to 0.01 (95 %-CI:-0.04,0.05). HBP mediated up to 8 % of the association between SOM clusters and CFI and high cholesterol up to 5 %. Air pollution and N-SES associated cognitive decline was partially mediated by depression. Only a small portion (<10 %) of the association was mediated by HBP and high cholesterol.

VasCog Screen test: sensitive in detecting cognitive impairment in patients who had a stroke or with heart failure

INTRODUCTION

Vascular diseases, such as stroke and heart failure (HF), are associated with cognitive decline. Vascular cognitive impairment (CI) is commonly found in patients who had a stroke and with HF, ranging from mild CI to dementia. Early detection of CI is crucial for effective management and rehabilitation. This study aimed to develop the VasCog Screen test, a screening tool to detect CI in patients who had a stroke and with HF.

METHOD

427 patients who had a stroke and with HF were assessed using cognitive measures including Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA) and a formal neuropsychological battery. The short-MoCA was derived and combined with Symbol Digit Modalities Test (SDMT) to create the VasCog Screen. The discriminatory ability of different tests for CI was compared, establishing optimal cut-off points. Variants of short-MoCA including the SDMT were also evaluated.

RESULTS

Similar prevalence rates of CI were found in stroke and HF cohorts. The most prevalent neuropsychological impairment was visuomotor speed, followed by visual memory and visuoconstruction. More than half of the patients were found to have CI. The VasCog Screen outperformed MMSE, MoCA and short-MoCA in detecting CI. The addition of SDMT to variants of the short-MoCA increased diagnostic accuracy.

CONCLUSION

The VasCog Screen test offers a cognitive screening tool, which is sensitive to cognitive deficits characteristically found in patients who had a stroke and with HF. It was found to have good sensitivity, specificity and classification accuracy. It is easy to administer in busy clinics, enabling early detection of CI and facilitating appropriate interventions.

Immunological aspects of central neurodegeneration

The etiology of various neurodegenerative disorders that mainly affect the central nervous system including (but not limited to) Alzheimer's disease, Parkinson's disease and Huntington's disease has classically been attributed to neuronal defects that culminate with the loss of specific neuronal populations. However, accumulating evidence suggests that numerous immune effector cells and the products thereof (including cytokines and other soluble mediators) have a major impact on the pathogenesis and/or severity of these and other neurodegenerative syndromes. These observations not only add to our understanding of neurodegenerative conditions but also imply that (at least in some cases) therapeutic strategies targeting immune cells or their products may mediate clinically relevant neuroprotective effects. Here, we critically discuss immunological mechanisms of central neurodegeneration and propose potential strategies to correct neurodegeneration-associated immunological dysfunction with therapeutic purposes.

Relative associations of behavioral and physiological risks for cardiometabolic disease with cognition in bipolar disorder during mid and later-life: findings from the UK biobank

BACKGROUND

Cardiometabolic disease risk factors are disproportionately prevalent in bipolar disorder (BD) and are associated with cognitive impairment. It is, however, unknown which health risk factors for cardiometabolic disease are relevant to cognition in BD. This study aimed to identify the cardiometabolic disease risk factors that are the most important correlates of cognitive impairment in BD; and to examine whether the nature of the relationships vary between mid and later life.

METHODS

Data from the UK Biobank were available for 966 participants with BD, aged between 40 and 69 years. Individual cardiometabolic disease risk factors were initially regressed onto a global cognition score in separate models for the following risk factor domains; (1) health risk behaviors (physical activity, sedentary behavior, smoking, and sleep) and (2) physiological risk factors, stratified into (2a) anthropometric and clinical risk (handgrip strength, body composition, and blood pressure), and (2b) cardiometabolic disease risk biomarkers (CRP, lipid profile, and HbA1c). A final combined multivariate regression model for global cognition was then fitted, including only the predictor variables that were significantly associated with cognition in the previous models.

RESULTS

In the final combined model, lower mentally active and higher passive sedentary behavior, higher levels of physical activity, inadequate sleep duration, higher systolic and lower diastolic blood pressure, and lower handgrip strength were associated with worse global cognition.

CONCLUSIONS

Health risk behaviors, as well as blood pressure and muscular strength, are associated with cognitive function in BD, whereas other traditional physiological cardiometabolic disease risk factors are not.

Cardiometabolic disease, cognitive decline, and brain structure in middle and older age

INTRODUCTION

The presence of multiple cardiometabolic diseases (CMDs) has been linked to increased dementia risk, but the combined influence of CMDs on cognition and brain structure across the life course is unclear.

METHODS

In the UK Biobank, 46,562 dementia-free participants completed a cognitive test battery at baseline and a follow-up visit 9 years later, at which point 39,306 also underwent brain magnetic resonance imaging. CMDs (diabetes, heart disease, and stroke) were ascertained from medical records. Data were analyzed using age-stratified (middle age [< 60] versus older [≥ 60]) mixed-effects models and linear regression.

RESULTS

A higher number of CMDs was associated with significantly steeper global cognitive decline in older (β = -0.008; 95% confidence interval: -0.012, -0.005) but not middle age. Additionally, the presence of multiple CMDs was related to smaller total brain volume, gray matter volume, white matter volume, and hippocampal volume and larger white matter hyperintensity volume, even in middle age.

DISCUSSION

CMDs are associated with cognitive decline in older age and poorer brain structural health beginning already in middle age.

Highlights

We explored the association of CMDs with cognitive decline and brain MRI measures.CMDs accelerated cognitive decline in older (≥60y) but not middle (<60) age.CMDs were associated with poorer brain MRI parameters in both middle and older age.Results highlight the connection between CMDs and cognitive/brain aging.

Xinshubao tablet rescues cognitive dysfunction in a mouse model of vascular dementia: Involvement of neurogenesis and neuroinflammation

Vascular dementia (VaD) represents a severe cognitive dysfunction syndrome closed linked to cardiovascular function. In the present study, we assessed the potential of Xinshubao tablet (XSB), a traditional Chinese prescription widely used for cardiovascular diseases, to mitigate neuropathological damage in a mouse model of VaD and elucidated the underlying mechanisms. Our findings revealed that oral administration of XSB rescued the cardiac dysfunction resulting from bilateral common carotid artery stenosis (BCAS), improved the cerebral blood flow (CBF) and cognitive function, reduced white matter injury, inhibited excessive microglial and astrocytic activation, stimulated hippocampal neurogenesis, and reduced neural apoptosis in the brains of BCAS mice. Mechanistically, RNA-seq analysis indicated that XSB treatment was significantly associated with neuroinflammation, vasculature development, and synaptic transmission, which were further confirmed by q-PCR assays. Western blot results revealed that XSB treatment hindered the nuclear translocation of nuclear factor-κB (NF-κB), thereby suppressing the NF-κB signaling pathway. These results collectively demonstrated that XSB could ameliorate cognitive dysfunction caused by BCAS through regulating CBF, reducing white matter lesions, suppressing glial activation, promoting neurogenesis, and mitigating neuroinflammation. Notably, the NF-κB signaling pathway emerged as a pivotal player in this mechanism.

Cognitive impairment and outcomes in older adults with non-ST-elevation acute coronary syndrome

OBJECTIVE

This study aimed to explore the prognostic impact of cognitive impairment on the long-term risk of major adverse cardiovascular events (MACEs) in older patients with non-ST-elevation acute coronary syndrome (NSTEACS) undergoing invasive treatment.

METHODS

Patients aged ≥75 years with NSTEACS undergoing an invasive strategy were included in the multicentre prospective study (NCT01933581). Montreal Cognitive Assessment was used to evaluate cognitive status at baseline (scores ≥26 classified as normal, <26 as cognitive impairment). Long-term follow-up data were obtained from electronic patient care records. The primary endpoint was MACE as a composite of all-cause deaths, reinfarction, stroke/transient ischaemic attack, urgent revascularisation and significant bleeding.

RESULTS

239 patients with baseline cognitive assessment completed long-term follow-up. Median age was 80.9 years (IQR 78.2-83.9 years) and 62.3% were male. On 5-year follow-up, there was no significant difference in the occurrence of MACE between the cognitively impaired group and the normal cognition group (p=0.155). Cognition status was not associated with MACE (HR 1.37 (95% CI 0.96 to 1.95); p=0.082). However, there was significantly more deaths (p=0.005) in those with cognitive impairment. Kaplan-Meier survival analysis (log-rank p=0.003) and Cox regression analysis (aHR 1.85 (95% CI 1.11 to 3.08); p=0.018) revealed increased risk of all-cause mortality, even after adjusting for frailty and GRACE (Global Registry of Acute Coronary Events) score.

CONCLUSION

Cognitive impairment in older patients with NSTEACS undergoing an invasive strategy was associated with long-term all-cause mortality. Routine cognitive screening may aid risk stratification and further studies are needed to identify how this should influence management strategies and individual decision-making in this patient group.

TRIAL REGISTRATION NUMBER

NCT01933581.

Associations between multimorbidity burden and Alzheimer's pathology in older adults without dementia: the CABLE study

Studies have shown that multimorbidity may be associated with the Alzheimer's disease (AD) stages, but it has not been fully characterized in patients without dementia. A total of 1402 Han Chinese older adults without dementia from Chinese Alzheimer's Biomarker and LifestylE (CABLE) study were included and grouped according to their multimorbidity patterns, defined by the number of chronic disorders and cluster analysis. Multivariable linear regression models were used to detect the associations with AD-related cerebrospinal fluid (CSF) biomarkers. Multimorbidity and severe multimorbidity (≥4 chronic conditions) were significantly associated with CSF amyloid and tau levels (pFDR < 0.05). Metabolic patterns were significantly associated with higher levels of CSF Aβ40 (β = 0.159, pFDR = 0.036) and tau (P-tau: β = 0.132, pFDR = 0.035; T-tau: β = 0.126, pFDR = 0.035). The above associations were only significant in the cognitively normal (CN) group. Multimorbidity was associated with brain AD pathology before any symptomatic evidence of cognitive impairment. Identifying such high-risk groups might allow tailored interventions for AD prevention.

Trends in the prevalence of cognitive impairment at old age in China, 2002-2018

INTRODUCTION

China has the world's largest number of older adults with cognitive impairment (CI). We aimed to examine secular trends in the prevalence of CI in China from 2002 to 2018.

METHODS

Generalized estimating equations (GEE) was used to assess changes in CI trend in 44,154 individuals (72,027 observations) aged 65 to 105 years old.

RESULTS

The prevalence of CI increased from 2002 to 2008 and then decreased until 2018. The age-standardized prevalence increased from 25.7% in 2002, 26.1% in 2005, to 28.2% in 2008, then decreased to 26.0% in 2011, 25.3% in 2014, and 24.9% in 2018. Females and those ≥ 80 years old had greater CI prevalence.

DISCUSSION

The prevalence of CI showed an inverted U shape from early 2000s to late 2010s with a peak in 2008. Follow-up studies are needed to confirm the decreasing trend after 2008 and examine the contributing factors and underlying mechanisms of this trend.

HIGHLIGHTS

Generalized estimating equations (GEE) were used to assess trends of changes in cognitive impairment (CI). CI prevalence in China increased from 2002 to 2008 and then decreased until 2018. Females and those ≥ 80 years old had greater CI prevalence. Stroke, diabetes, and cigarette smoking were risk factors for CI.

Arterial stiffness mediates the association between age and processing speed at low levels of microvascular function in humans across the adult lifespan

The function of micro- and macrovessels within the peripheral vasculature has been identified as a target for the investigation of potential cardiovascular-based promoters of cognitive decline. However, little remains known regarding the interaction of the micro- and macrovasculature as it relates to cognitive function, especially in cognitively healthy individuals. Therefore, our purpose was to unravel peripheral factors that contribute to the association between age and processing speed. Ninety-nine individuals (51 men, 48 women) across the adult life span (19-81 yr) were used for analysis. Arterial stiffness was quantified as carotid-femoral pulse-wave velocity (cfPWV) and near-infrared spectroscopy assessed maximal tissue oxygenation (Sto2max) following a period of ischemia. Processing speed was evaluated with Trail Making Test (TMT) Parts A and B. Measures of central (cPP) and peripheral pulse pressure (pPP) were also collected. Moderated mediation analyses were conducted to determine contributions to the age and processing speed relation, and first-order partial correlations were used to assess associations while controlling for the linear effects of age. A P ≤ 0.05 was considered statistically significant. At low levels of Sto2max, there was a significant positive (b = 1.92; P = 0.005) effect of cfPWV on time to completion on TMT part A. In addition, cPP (P = 0.028) and pPP (P = 0.027) remained significantly related to part A when controlling for age. These results suggested that the peripheral microvasculature may be a valuable target for delaying cognitive decline, especially in currently cognitively healthy individuals. Furthermore, we reinforced current evidence that pulse pressure is a key endpoint for trials aimed at preventing or delaying the onset of cognitive decline.NEW & NOTEWORTHY Arterial stiffness partially mediates the association between age and processing speed in the presence of low microvascular function, as demarcated by maximum tissue oxygenation following ischemia. Central and peripheral pulse pressure remained associated with processing speed even after controlling for age. Our findings were derived from a sample that was determined to be cognitively healthy, which highlights the potential for these outcomes to be considered during trials aimed at the prevention of cognitive decline.

Causality between cognitive performance and cardiovascular disease: A bidirectional Mendelian randomization study

BACKGROUND

Growing evidence points to a connection between cardiovascular disease and cognitive impairment. These observational study findings, however, were not all uniform, and some did not discover a link like this. Investigating the causal link between cognitive impairment and cardiovascular disease is vital.

METHOD

Using publicly available genome-wide association study (GWAS) summary datasets and stringent screening instrumental variables, we carried out a bidirectional Mendelian randomization study. To investigate the causality between cardiovascular disease and cognitive impairment, three different MR techniques-inverse variance weighted (IVW), MR-Egger, and weighted median-as well as various sensitivity analyses-Cochran's Q, ivw_radial, leave-one-out (LOO), MR-Egger intercept, and MR-PRESSO-were used.

RESULTS

The causal impact of genetically predicted cognitive performance on hypertension, atrial fibrillation, heart failure, coronary atherosclerosis, coronary artery disease, and myocardial infarction was detected in the forward MR analysis, but not stroke or any subtypes. We only discover the causal effects of hypertension, any stroke, and its subtypes (ischemic and small vessel stroke) on cognitive performance in the reverse MR analysis.

CONCLUSION

This MR analysis offers proof of a causal link between cognitive impairment and elevated cardiovascular disease risk. Our research emphasizes the value of cognitively impaired patients being screened for cardiovascular disease, which may offer fresh perspectives on cardiovascular disease prevention.

The influence of screen time on behaviour and emotional problems among adolescents: A comparison study of the pre-, peak, and post-peak periods of COVID-19

The coronavirus disease 2019 (COVID-19) pandemic has brought drastic changes globally in the past three years, one of which is an increase in the use of digital media or electronic devices. Previous studies have shown that long screen time may stimulate the neurobiological system, resulting in various behavioural and emotional problems; however, there is insufficient population-based evidence. This study aimed to investigate the influence of screen time on behavioural and emotional problems in Indonesian adolescents at three time points: the pre-, peak, and post-peak periods of COVID-19. Data were collected using an online community mental health survey. This survey incorporated the Youth Screen Time Survey to gauge screen time and the adolescent version of the Strengths and Difficulties Questionnaire to assess emotional, conduct, and prosocial behaviour problems. The participants were adolescents in secondary and senior high schools, with 337, 423, and 1,096 participants from the pre-, peak-, and post-pandemic periods, respectively, included in the analysis. Daily average screen time was compared, followed by the calculation of odds ratios for screen time and mental health problems during the different periods. The results demonstrated significant differences in adolescents' total daily average screen time between the different pandemic periods. Decreased screen time was associated with reduced emotional, conduct, and prosocial behaviour problems, especially during the peak period. Thus, psychoeducation on screen time in adolescents should be considered as a point of interest for mental well-being interventions.

Patterns of multimorbidity in primary care electronic health records: A systematic review

Background

Multimorbidity, the coexistence of multiple chronic conditions in an individual, is a complex phenomenon that is highly prevalent in primary care settings, particularly in older individuals. This systematic review summarises the current evidence on multimorbidity patterns identified in primary care electronic health record (EHR) data.

Methods

Three databases were searched from inception to April 2022 to identify studies that derived original multimorbidity patterns from primary care EHR data. The quality of the included studies was assessed using a modified version of the Newcastle-Ottawa Quality Assessment Scale.

Results

Sixteen studies were included in this systematic review, none of which was of low quality. Most studies were conducted in Spain, and only one study was conducted outside of Europe. The prevalence of multimorbidity (i.e. two or more conditions) ranged from 14.0% to 93.9%. The most common stratification variable in disease clustering models was sex, followed by age and calendar year. Despite significant heterogeneity in clustering methods and disease classification tools, consistent patterns of multimorbidity emerged. Mental health and cardiovascular patterns were identified in all studies, often in combination with diseases of other organ systems (e.g. neurological, endocrine).

Discussion

These findings emphasise the frequent coexistence of physical and mental health conditions in primary care, and provide useful information for the development of targeted preventive and management strategies. Future research should explore mechanisms underlying multimorbidity patterns, prioritise methodological harmonisation to facilitate the comparability of findings, and promote the use of EHR data globally to enhance our understanding of multimorbidity in more diverse populations.

Cognitive complaints in older adults: relationships between self and informant report, objective test performance, and symptoms of depression

This study explored the relationships between objective measures of cognitive functioning, self and informant reports of cognitive problems in daily life, and depression screening in older adults who had been referred because of reported or suspected cognitive changes. We used archival data from 100, predominantly White (97%), typically educated (M = 13.25 years), older adults (M = 70.38 years) who received an outpatient neuropsychological evaluation. We characterized the cognitive performance using the CVLT-II Total score. We characterized patient and collateral reports using the BRIEF-A MI index, a normed scale of cognitive problems in daily life. We also incorporated a depression screener (PHQ-9) into our analyses. Multiple linear regression analysis revealed that only the informant reported problems in daily life, using the BRIEF-A MI index, was a significant predictor of objective cognitive deficits, as defined by CVLT-II Total scores. Self BRIEF-A MI index scores were not significant predictors of CVLT-II Total performance after we accounted for depression using the patient's PHQ-9 score. Additionally, elevated depression widened the discrepancy between raters, with elevated depression associated with worsening sself-report scores compared to informant-reported scores. As informant-reported problems were the strongest predictor of cognitive deficits, we recommend routine collection of collateral informant reports in the neuropsychological evaluation of older adults referred for cognitive concerns. We also recommend incorporating self-ratings of daily life functioning and screening for depression to contextualize patient complaints and address their concerns, even in the absence of objective cognitive dysfunction.

Association Between Onset Age of Coronary Heart Disease and Incident Dementia: A Prospective Cohort Study

BACKGROUND

The association of age at coronary heart disease (CHD) onset with incident dementia remains unexplored. This study aimed to examine whether younger onset age of CHD is associated with a higher risk of incident dementia.

METHODS AND RESULTS

Data were obtained from the UK Biobank. Information on the diagnosis of CHD and dementia was collected at baseline and follow-ups. Propensity score matching method and Cox proportional hazards models were used to evaluate the association between different ages at CHD onset and incident dementia. A total of 432 667 adults (mean±SD age, 56.9±8.1 years) were included, of whom 11.7% had CHD. Compared with participants without CHD, participants with CHD exhibited higher risks of developing all-cause dementia, Alzheimer's disease, and vascular dementia. More importantly, younger age at CHD onset (per 10-year decrease) was significantly associated with elevated risks of all-cause dementia (hazard ratio [HR], 1.25 [95% CI, 1.20-1.30]; P<0.001), Alzheimer's disease (HR, 1.29 [95% CI, 1.20-1.38]; P<0.001), and vascular dementia (HR, 1.22 [95% CI, 1.13-1.31]; P<0.001). After propensity score matching, patients with CHD had significantly higher risks of all-cause dementia, Alzheimer's disease, and vascular dementia than matched controls among all onset age groups, and the HRs gradually elevated with decreasing age at CHD onset.

CONCLUSIONS

Younger onset age of CHD is associated with higher risks of incident all-cause dementia, Alzheimer's disease, and vascular dementia, underscoring the necessity to pay attention to the neurocognitive status of individuals diagnosed with CHD at younger age to conduct timely interventions to attenuate subsequent risk of incident dementia.

Age at Diagnosis of Atrial Fibrillation and Incident Dementia

Importance

Epidemiological evidence regarding the association between atrial fibrillation (AF) onset age and risk of incident dementia remains unexplored.

Objective

To examine whether age at AF diagnosis is associated with risk of incident dementia and its subtypes.

Design, Setting, and Participants

This prospective, population-based cohort study used data from UK Biobank, a public, open-access database in the UK with baseline information collected from 2006 to 2010. A total of 433 746 participants were included in the main analysis after excluding participants with a diagnosis of dementia or AF at baseline, missing data on covariates, or having dementia before AF onset during a median follow-up of 12.6 years. Data were analyzed from October to December 2022.

Exposures

AF diagnosis and age at AF diagnosis according to age groups (<65 years, 65-74 years, or ≥75 years).

Main Outcomes and Measures

Incident dementia, ascertained through linkage from multiple databases until December 31, 2021. Cox proportional hazards models and the propensity score matching method were adopted to estimate the association between AF onset age and incident dementia.

Results

Of 433 746 included participants, 236 253 (54.5%) were female, the mean (SD) age was 56.9 (8.1) years, and 409 990 (94.5%) were White. Compared with individuals without AF, 30 601 individuals with AF had a higher risk of developing all-cause dementia (adjusted hazard ratio [HR], 1.42; 95% CI, 1.32-1.52) and vascular dementia (VD; adjusted HR, 2.06; 95% CI, 1.80-2.36), but not Alzheimer disease (AD; adjusted HR, 1.08; 95% CI, 0.96-1.21). Among participants with AF, younger age at AF onset was associated with higher risks of developing all-cause dementia (adjusted HR per 10-year decrease, 1.23; 95% CI, 1.16-1.32), AD (adjusted HR per 10-year decrease, 1.27; 95% CI, 1.13-1.42), and VD (adjusted HR per 10-year decrease, 1.35; 95% CI, 1.20-1.51). After propensity score matching, individuals with AF diagnosed before age 65 years had the highest HR of developing all-cause dementia (adjusted HR, 1.82; 95% CI, 1.54-2.15), followed by AF diagnosed at age 65 to 74 years (adjusted HR, 1.47; 95% CI, 1.31-1.65) and diagnosed at age 75 years or older (adjusted HR, 1.11; 95% CI, 0.96-1.28). Similar results can be seen in AD and VD.

Conclusions and Relevance

In this prospective cohort study, earlier onset of AF was associated with an elevated risk of subsequent all-cause dementia, AD, and VD, highlighting the importance of monitoring cognitive function among patients with AF, especially those younger than 65 years at diagnosis.

Resting heart rate, cognitive function, and inflammation in older adults: a population-based study

BACKGROUND

Emerging evidence has linked elevated resting heart rate (RHR) with poor cognitive function in older adults, but the mechanisms underlying their association are poorly understood.

METHODS

This population-based cross-sectional study included 4510 dementia-free participants (age ≥ 65 years; 56.9% females; 38.3% no formal education) in the baseline examination of the Multidomain Interventions to Delay Dementia and Disability in Rural China study. Of these, 1,386 had data on serum proinflammatory cytokines and adhesion molecules. RHR was measured using 12-lead electrocardiograph. We used the Mini-Mental State Examination (MMSE) and a neuropsychological test battery to assess cognitive function. Data were analyzed using the general linear and restricted cubic splines models.

RESULTS

People with high RHR were more likely to have cardiometabolic diseases and worse cognitive function (p < 0.05). There was an inverted J-shaped association of RHR with MMSE and attention scores. Having RHR ≥ 80 bpm (vs. 60-69 bpm) was significantly associated with the multivariable-adjusted β coefficients of - 0.58 [95% confidence interval (CI), - 1.00, - 0.16] for MMSE score and - 0.08 (- 0.15, - 0.01) for attention score. In the serum biomarker subsample, RHR was linearly associated with serum interleukin-6 (IL-6) (β coefficient = 0.19; 95%CI 0.14, 0.24), IL-8 (0.08; 0.02, 0.13), IL-10 (0.09; 0.04, 0.15), tumor necrosis factor-α (0.06; 0.01, 0.11), monocyte chemotactic protein-1 (0.09; 0.04, 0.15), intercellular adhesion molecule-1 (0.16; 0.11, 0.22), and vascular cell adhesion molecule-1 (0.11; 0.06, 0.16).

CONCLUSIONS

There is an inverted J-shaped association of RHR with attention and global cognition. Poor cognitive function and high RHR may be linked through systemic low-grade inflammation and endothelial injury.

Oxytocin as neuro-hormone and neuro-regulator exert neuroprotective properties: A mechanistic graphical review

BACKGROUND

Neurodegeneration is progressive cell loss in specific neuronal populations, often resulting in clinical consequences with significant medical, societal, and economic implications. Because of its antioxidant, anti-inflammatory, and anti-apoptotic properties, oxytocin has been proposed as a potential neuroprotective and neurobehavioral therapeutic agent, including modulating mood disturbances and cognitive enchantment.

METHODS

Literature searches were conducted using the following databases Web of Science, PubMed, Elsevier Science Direct, Google Scholar, the Core Collection, and Cochrane from January 2000 to February 2023 for articles dealing with oxytocin neuroprotective properties in preventing or treating neurodegenerative disorders and diseases with a focus on oxidative stress, inflammation, and apoptosis/cell death.

RESULTS

The neuroprotective effects of oxytocin appears to be mediated by its anti-inflammatory properties, inhibition of neuro inflammation, activation of several antioxidant enzymes, inhibition of oxidative stress and free radical formation, activation of free radical scavengers, prevent of mitochondrial dysfunction, and inhibition of apoptosis.

CONCLUSION

Oxytocin acts as a neuroprotective agent by preventing neuro-apoptosis, neuro-inflammation, and neuronal oxidative stress, and by restoring mitochondrial function.

Association Between Metabolic Risk Factors and Cognitive Impairment in Schizophrenia Based on Sex

OBJECTIVE

Sex differences have been observed in many aspects of schizophrenia, including cognitive deficits. Despite extensive research into the relationship between metabolic factors and cognitive deficits in schizophrenia, few studies have explored the potential sex difference in their association.

METHODS

We recruited 358 schizophrenia patients and 231 healthy controls. The participants underwent measurements of body mass index (BMI), waist circumference, blood pressure, triglycerides, high-density lipoprotein cholesterol, and fasting blood glucose. Metabolic risk factors included abdominal obesity, hypertension, hyperglycemia, and dyslipidemia. A collection of these metabolic risk factors has been defined as metabolic syndrome. These diagnoses were based on the criteria of the National Cholesterol Education Program's Adult Treatment Panel III. Cognitive performance was measured using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). A descriptive analysis, difference analysis, and linear regression model were used to identify the metabolic risk factors for cognitive function in schizophrenia.

RESULTS

Our findings revealed sex differences in the rate of abdominal obesity and hypertension in schizophrenic patients. Additionally, we observed sex differences in the association between metabolic risk factors and cognitive impairment in schizophrenia. Specifically, hyperglycemia was associated with the immediate memory index score of RBANS in male patients, while dyslipidemia was associated with language, attention, delayed memory index scores, and RBANS total score in female patients.

CONCLUSION

Our results suggest that sex should be considered when evaluating the impact of metabolic disorders on the cognitive function of schizophrenic patients. Moreover, our study identifies hyperglycemia and dyslipidemia as potential targets for precise treatment by sex stratification, which could benefit the improvement of cognitive impairment in schizophrenic patients.

Association of Long-term Exposure to Air Pollution and Dementia Risk: The Role of Homocysteine, Methionine, and Cardiovascular Burden

BACKGROUND AND OBJECTIVES

Growing evidence links air pollution with dementia risk, but the biological mechanisms are largely unknown. We investigated the role played by homocysteine (tHcy) and methionine in this association and explored whether this could be explained by cardiovascular diseases (CVDs).

METHODS

Data were extracted from the ongoing Swedish National study on Aging and Care in Kungsholmen (SNAC-K), a longitudinal population-based study. At baseline, 2,512 dementia-free participants were examined up to 2013 (mean follow-up: 5.18 ± 2.96 years). Two air pollutants (particulate matter ≤2.5 μm [PM2.5] and nitrogen oxides [NOx]) were assessed yearly from 1990 until 2013 using dispersion models at residential addresses. The hazard ratio of dementia over air pollution levels was estimated using Cox models adjusted for age, sex, education, smoking, socioeconomic status, physical activity, retirement age, creatinine, year of assessment, and the use of supplements. The total effect of air pollutants on dementia was decomposed into 4 pathways involving tHcy/methionine: (1) direct effect; (2) indirect effect (mediation); (3) effect due to interaction; and (4) effect due to both mediation and interaction. To test whether the association was independent from CVDs (ischemic heart disease, atrial fibrillation, heart failure, and stroke), we repeated the analyses excluding those individuals who developed CVDs.

RESULTS

The mean age of the study participants was 73.4 years (SD: 10.4), and 62.1% were female individuals. During an average period of 5 years (mean: 5.18; SD: 2.96 years), 376 cases with incident dementia were identified. There was a 70% increased hazard of dementia per unit increase of PM2.5 during the 5 years before baseline (hazard ratio [HR]: 1.71; 95% CI 1.33-2.09). Overall, 50% (51.6%; 95% CI 9.0-94.1) of the total effect of PM2.5 on dementia was due to mediation of tHcy (6.6%; 95% CI 1.6-11.6) and/or interaction (47.8%; 95% CI 4.9-91.7) with tHcy and 48.4% (p = 0.03) to the direct effect of PM2.5 on dementia. High levels of methionine reduced the dementia hazard linked to PM2.5 by 31% (HR: 0.69; 95% CI 0.56-0.85) with 24.8% attributable to the interaction with methionine and 25.9% (p = 0.001) to the direct effect of PM2.5. No mediation effect was found through methionine. Attenuated results were obtained for NOx. Findings for tHcy were attenuated after excluding those who developed CVDs, while remained similar for methionine.

DISCUSSION

High levels of homocysteine enhanced the dementia risk attributed to air pollution, while high methionine concentrations reduced this risk. The impact of homocysteine on cardiovascular conditions partly explains this association. Alternative pathways other than cardiovascular mechanisms may be at play between methionine and dementia.

Age at Onset of Heart Failure and Subsequent Risk of Dementia: A Longitudinal Cohort Study

BACKGROUND

The average age at onset of heart failure (HF) shows a progressive decrease in recent years; however, the association between age at onset of HF and risk of subsequent dementia remains undetermined.

OBJECTIVES

The study sought to examine whether younger onset age of HF is associated with a higher risk of incident dementia.

METHODS

Individual-level data from the UK Biobank cohort study were analyzed in the present study. Cox regression models and the propensity score matching method were used to analyze the associations of HF and its onset age with subsequent all-cause dementia, Alzheimer's disease (AD), and vascular dementia (VD).

RESULTS

Compared with 442,791 participants without HF, those with HF had a higher risk of all-cause dementia (HR: 1.14). Among 14,413 participants with HF, multivariable-adjusted HRs for all-cause dementia, AD, and VD were 1.18, 1.64, and 1.27, respectively, per 10-year decrease in age at HF onset. The propensity score matching analyses found that the strength of association between HF and all-cause dementia increased with decreasing onset age of HF (≥75 years, HR: 1.05; 65-74 years, HR: 1.10; <65 years, HR: 1.67) after multivariable adjustment. Similarly, participants with onset age of HF <65 years had the greatest HRs for incident AD and VD, compared with their matched control subjects.

CONCLUSIONS

Younger age at HF onset was associated with increased risk of dementia. Individuals with an onset age of HF before 65 years of age may represent a particularly vulnerable population for dementia irrespective of subtypes and need careful monitoring and timely intervention to attenuate subsequent risk of incident dementia.

Association between cardiovascular diseases and dementia among various age groups: a population-based cohort study in older adults

The link between cardiovascular (CV) risk factors or diseases and dementia is documented. There is conflicting evidence whether age moderates the association. We need to study this gap so that research and clinical initiatives target appropriate age groups. A cohort of 320,630 adult patients without dementia was built using Quebec healthcare databases (1998-2010). The CV risk factors were hypertension, diabetes and dyslipidemia, while diseases included stroke, myocardial infarction (MI), chronic heart failure (HF), and atrial fibrillation (AF). Dementia risk and CV risk factors or diseases were assessed using incidence rate ratios and Cox regression across age groups. The cohort presented by mainly female sex (67.7%) and mean age of 74.1 years. Incident rate of dementia increased with age, ranging from 4.1 to 93.5 per 1000 person-years. Diabetes, stroke, HF and AF were significantly associated with dementia risk, hazard ratios ranged from 1.08 to 3.54. The strength of association decreased in advanced age for diabetes, stroke and HF. The results suggest that prevention of diabetes, stroke, HF and AF are crucial to mitigate dementia risk. The pathophysiology of dementia in younger and older populations seems to differ, with less impact of CV risk factors in advanced age.

Multimorbidity patterns and 18-year transitions from normal cognition to dementia and death: A population-based study

BACKGROUND

Several chronic diseases accelerate cognitive decline; however, it is still unknown how different patterns of multimorbidity influence individuals' trajectories across the cognitive continuum.

OBJECTIVES

We aimed to investigate the impact of multimorbidity and of specific multimorbidity patterns on the transitions across cognitive stages (normal cognition, cognitive impairment, no dementia [CIND], dementia) and death.

METHODS

We included 3122 dementia-free individuals from the Swedish National study on Aging and Care in Kungsholmen. Using fuzzy c-means cluster analysis, multimorbid participants were classified into mutually exclusive groups characterized by commonly coexisting chronic diseases. Participants were followed up to 18 years to detect incident CIND, dementia, or death. Transition hazard ratios (HRs), life expectancies, and time spent in different cognitive stages were estimated using multistate Markov models.

RESULTS

At baseline, five multimorbidity patterns were identified: neuropsychiatric, cardiovascular, sensory impairment/cancer, respiratory/metabolic/musculoskeletal, and unspecific. Compared to the unspecific pattern, the neuropsychiatric and sensory impairment/cancer ones showed reduced hazards of reverting from CIND to normal cognition (HR 0.53, 95% CI 0.33-0.85 and HR 0.60, 95% CI 0.39-0.91). Participants in the cardiovascular pattern exhibited an increased hazard of progression from CIND to dementia (HR 1.70, 95% CI 1.15-2.52) and for all transitions to death. Subjects with the neuropsychiatric and cardiovascular patterns showed reduced life expectancy at age 75, with an anticipation of CIND (up to 1.6 and 2.2 years, respectively) and dementia onset (up to 1.8 and 3.3 years, respectively).

CONCLUSIONS

Multimorbidity patterns differentially steer individual trajectories across the cognitive continuum of older adults and may be used as a risk stratification tool.

Cardiovascular risk factors in secondary progressive multiple sclerosis: A cross-sectional analysis from the MS-STAT2 randomized controlled trial

BACKGROUND AND PURPOSE

There is increasing evidence that cardiovascular risk (CVR) contributes to disability progression in multiple sclerosis (MS). CVR is particularly prevalent in secondary progressive MS (SPMS) and can be quantified through validated composite CVR scores. The aim was to examine the cross-sectional relationships between excess modifiable CVR, whole and regional brain atrophy on magnetic resonance imaging, and disability in patients with SPMS.

METHODS

Participants had SPMS, and data were collected at enrolment into the MS-STAT2 trial. Composite CVR scores were calculated using the QRISK3 software. Prematurely achieved CVR due to modifiable risk factors was expressed as QRISK3 premature CVR, derived through reference to the normative QRISK3 dataset and expressed in years. Associations were determined with multiple linear regressions.

RESULTS

For the 218 participants, mean age was 54 years and median Expanded Disability Status Scale was 6.0. Each additional year of prematurely achieved CVR was associated with a 2.7 mL (beta coefficient; 95% confidence interval 0.8-4.7; p = 0.006) smaller normalized whole brain volume. The strongest relationship was seen for the cortical grey matter (beta coefficient 1.6 mL per year; 95% confidence interval 0.5-2.7; p = 0.003), and associations were also found with poorer verbal working memory performance. Body mass index demonstrated the strongest relationships with normalized brain volumes, whilst serum lipid ratios demonstrated strong relationships with verbal and visuospatial working memory performance.

CONCLUSIONS

Prematurely achieved CVR is associated with lower normalized brain volumes in SPMS. Future longitudinal analyses of this clinical trial dataset will be important to determine whether CVR predicts future disease worsening.

Regional Vulnerability of the Corpus Callosum in the Context of Cardiovascular Risk

Many factors outside of cardiovascular health can impact the structure of white matter. Identification of reliable and clinically meaningful biomarkers of the neural effects of systemic and cardiovascular health are needed to refine etiologic predictions. We examined whether the corpus callosum demonstrates regional vulnerability to systemic cardiovascular risk factors. Three hundred and ninety-four older adults without dementia completed brain MRI, neurobehavioral evaluations, and blood draws. A subset (n = 126, n = 128) of individuals had blood plasma analyzed for inflammatory markers of interest (IL-6 and TNF-alpha). Considering diffusion tensor imaging (DTI) is a particularly reliable measure of white matter integrity, we utilized DTI to examine fractional anisotropy (FA) of anterior and posterior regions of the corpus callosum. Using multiple linear regression models, we simultaneously examined FA of the genu and the splenium to compare their associations with systemic and cardiovascular risk factors. Lower FA of the genu but not splenium was associated with greater systemic and cardiovascular risk, including higher systolic blood pressure (β = -0.17, p = .020), hemoglobin A1C (β = -0.21, p = .016) and IL-6 (β = -0.34, p = .005). FA of the genu was uniquely associated with cognitive processing speed (β = 0.20, p = .0015) and executive functioning (β = 0.15, p = .012), but not memory performances (β = 0.05, p = .357). Our results demonstrated differential vulnerability of the corpus callosum, such that frontal regions showed stronger, independent associations with biomarkers of systemic and cardiovascular health in comparison to posterior regions. Posterior white matter integrity may not reflect cardiovascular health. Clinically, these findings support the utility of examining the anterior corpus callosum as an indicator of cerebrovascular health.

Neuropsychological outcome after cardiac arrest: results from a sub-study of the targeted hypothermia versus targeted normothermia after out-of-hospital cardiac arrest (TTM2) trial

BACKGROUND

Cognitive impairment is common following out-of-hospital cardiac arrest (OHCA), but the nature of the impairment is poorly understood. Our objective was to describe cognitive impairment in OHCA survivors, with the hypothesis that OHCA survivors would perform significantly worse on neuropsychological tests of cognition than controls with acute myocardial infarction (MI). Another aim was to investigate the relationship between cognitive performance and the associated factors of emotional problems, fatigue, insomnia, and cardiovascular risk factors following OHCA.

METHODS

This was a prospective case-control sub-study of The Targeted Hypothermia versus Targeted Normothermia after Out-of-Hospital Cardiac Arrest (TTM2) trial. Eight of 61 TTM2-sites in Sweden, Denmark, and the United Kingdom included adults with OHCA of presumed cardiac or unknown cause. A matched non-arrest control group with acute MI was recruited. At approximately 7 months post-event, we administered an extensive neuropsychological test battery and questionnaires on anxiety, depression, fatigue, and insomnia, and collected information on the cardiovascular risk factors hypertension and diabetes.

RESULTS

Of 184 eligible OHCA survivors, 108 were included, with 92 MI controls enrolled. Amongst OHCA survivors, 29% performed z-score ≤ - 1 (at least borderline-mild impairment) in ≥ 2 cognitive domains, 14% performed z-score ≤ - 2 (major impairment) in ≥ 1 cognitive domain while 54% performed without impairment in any domain. Impairment was most pronounced in episodic memory, executive functions, and processing speed. OHCA survivors performed significantly worse than MI controls in episodic memory (mean difference, MD = - 0.37, 95% confidence intervals [- 0.61, - 0.12]), verbal (MD = - 0.34 [- 0.62, - 0.07]), and visual/constructive functions (MD = - 0.26 [- 0.47, - 0.04]) on linear regressions adjusted for educational attainment and sex. When additionally adjusting for anxiety, depression, fatigue, insomnia, hypertension, and diabetes, executive functions (MD = - 0.44 [- 0.82, - 0.06]) were also worse following OHCA. Diabetes, symptoms of anxiety, depression, and fatigue were significantly associated with worse cognitive performance.

CONCLUSIONS

In our study population, cognitive impairment was generally mild following OHCA. OHCA survivors performed worse than MI controls in 3 of 6 domains. These results support current guidelines that a post-OHCA follow-up service should screen for cognitive impairment, emotional problems, and fatigue.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03543371. Registered 1 June 2018.

Cardiovascular and metabolic health is associated with functional brain connectivity in middle-aged and older adults: Results from the Human Connectome Project-Aging study

Several cardiovascular and metabolic indicators, such as cholesterol and blood pressure have been associated with altered neural and cognitive health as well as increased risk of dementia and Alzheimer's disease in later life. In this cross-sectional study, we examined how an aggregate index of cardiovascular and metabolic risk factor measures was associated with correlation-based estimates of resting-state functional connectivity (FC) across a broad adult age-span (36-90+ years) from 930 volunteers in the Human Connectome Project Aging (HCP-A). Increased (i.e., worse) aggregate cardiometabolic scores were associated with reduced FC globally, with especially strong effects in insular, medial frontal, medial parietal, and superior temporal regions. Additionally, at the network-level, FC between core brain networks, such as default-mode and cingulo-opercular, as well as dorsal attention networks, showed strong effects of cardiometabolic risk. These findings highlight the lifespan impact of cardiovascular and metabolic health on whole-brain functional integrity and how these conditions may disrupt higher-order network integrity.

Cognitive trajectories and incident dementia after a cardiovascular event in older adults

INTRODUCTION

Cardiovascular disease (CVD) is a recognized risk factor for dementia. Here we determined the extent to which an incident CVD event modifies the trajectory of cognitive function and risk of dementia.

METHODS

19,114 adults (65+) without CVD or dementia were followed prospectively over 9 years. Incident CVD (fatal coronary heart disease, nonfatal myocardial infarction [MI], stroke, hospitalization for heart failure) and dementia (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria) were adjudicated by experts.

RESULTS

Nine hundred twenty-two participants had incident CVD, and 44 developed dementia after CVD (4.9% vs. 4.4% for participants without CVD). Following a CVD event there was a short-term drop in processing speed (-1.97, 95% confidence interval [CI]: -2.57 to -1.41), but there was no significant association with longer-term processing speed. In contrast, faster declines in trajectories of global function (-0.56, 95% CI: -0.76 to -0.36), episodic memory (-0.10, 95% CI: -0.16 to -0.04), and verbal fluency (-0.19, 95% CI: -0.30 to -0.01) were observed.

DISCUSSION

Findings highlight the importance of monitoring cognition after a CVD event.

Using Hypothesis-Led Machine Learning and Hierarchical Cluster Analysis to Identify Disease Pathways Prior to Dementia: Longitudinal Cohort Study

BACKGROUND

Dementia development is a complex process in which the occurrence and sequential relationships of different diseases or conditions may construct specific patterns leading to incident dementia.

OBJECTIVE

This study aimed to identify patterns of disease or symptom clusters and their sequences prior to incident dementia using a novel approach incorporating machine learning methods.

METHODS

Using Taiwan's National Health Insurance Research Database, data from 15,700 older people with dementia and 15,700 nondementia controls matched on age, sex, and index year (n=10,466, 67% for the training data set and n=5234, 33% for the testing data set) were retrieved for analysis. Using machine learning methods to capture specific hierarchical disease triplet clusters prior to dementia, we designed a study algorithm with four steps: (1) data preprocessing, (2) disease or symptom pathway selection, (3) model construction and optimization, and (4) data visualization.

RESULTS

Among 15,700 identified older people with dementia, 10,466 and 5234 subjects were randomly assigned to the training and testing data sets, and 6215 hierarchical disease triplet clusters with positive correlations with dementia onset were identified. We subsequently generated 19,438 features to construct prediction models, and the model with the best performance was support vector machine (SVM) with the by-group LASSO (least absolute shrinkage and selection operator) regression method (total corresponding features=2513; accuracy=0.615; sensitivity=0.607; specificity=0.622; positive predictive value=0.612; negative predictive value=0.619; area under the curve=0.639). In total, this study captured 49 hierarchical disease triplet clusters related to dementia development, and the most characteristic patterns leading to incident dementia started with cardiovascular conditions (mainly hypertension), cerebrovascular disease, mobility disorders, or infections, followed by neuropsychiatric conditions.

CONCLUSIONS

Dementia development in the real world is an intricate process involving various diseases or conditions, their co-occurrence, and sequential relationships. Using a machine learning approach, we identified 49 hierarchical disease triplet clusters with leading roles (cardio- or cerebrovascular disease) and supporting roles (mental conditions, locomotion difficulties, infections, and nonspecific neurological conditions) in dementia development. Further studies using data from other countries are needed to validate the prediction algorithms for dementia development, allowing the development of comprehensive strategies to prevent or care for dementia in the real world.

Ischemic Heart Disease and Vascular Risk Factors Are Associated With Accelerated Brain Aging

BACKGROUND

Ischemic heart disease (IHD) has been linked with poor brain outcomes. The brain magnetic resonance imaging-derived difference between predicted brain age and actual chronological age (brain-age delta in years, positive for accelerated brain aging) may serve as an effective means of communicating brain health to patients to promote healthier lifestyles.

OBJECTIVES

The authors investigated the impact of prevalent IHD on brain aging, potential underlying mechanisms, and its relationship with dementia risk, vascular risk factors, cardiovascular structure, and function.

METHODS

Brain age was estimated in subjects with prevalent IHD (n = 1,341) using a Bayesian ridge regression model with 25 structural (volumetric) brain magnetic resonance imaging features and built using UK Biobank participants with no prevalent IHD (n = 35,237).

RESULTS

Prevalent IHD was linked to significantly accelerated brain aging (P < 0.001) that was not fully mediated by microvascular injury. Brain aging (positive brain-age delta) was associated with increased risk of dementia (OR: 1.13 [95% CI: 1.04-1.22]; P = 0.002), vascular risk factors (such as diabetes), and high adiposity. In the absence of IHD, brain aging was also associated with cardiovascular structural and functional changes typically observed in aging hearts. However, such alterations were not linked with risk of dementia.

CONCLUSIONS

Prevalent IHD and coexisting vascular risk factors are associated with accelerated brain aging and risk of dementia. Positive brain-age delta representing accelerated brain aging may serve as an effective communication tool to show the impact of modifiable risk factors and disease supporting preventative strategies.

Contribution of life course cardiovascular risk factors to racial disparities in dementia incidence

Background

Racial disparities in dementia outcomes persist in the United States. Targeting modifiable risk factors, including cardiovascular risk factors (CVRFs), is a conceivable way to reduce health disparities. Life course CVRFs are often higher in non-White adults and are associated with risk of dementia, but it is unknown whether they contribute to racial disparities in dementia and cognition.

Methods

Using a pooled cohort of 4,159 White and 939 Black participants aged 65-95 years, we conducted a mediation analysis to estimate the proportional effect of race on dementia that is explained by four CVRFs imputed over the life course (20-49, 50-69, and 70-89 years of age): body mass index, fasting glucose, systolic blood pressure, and low-density lipoprotein cholesterol.

Results

Compared to White participants, Black participants had greater risk of dementia (adjusted OR = 1.37; 95% CI: 1.17-1.60). BMI and fasting glucose over the life course were significant mediators of the effect of race on dementia risk, mediating 39.1% (95% CI: 10.5-67.8%) and 8.2% (95% CI: 0.1-16.2%) of the effect, adjusted for sex and age. All four CVRFs together were also significant mediators of the effect of race on scores on global cognition and processing speed, accounting for approximately 11% of the effect.

Conclusions

We found that CVRFs across the life course partially explain disparities in dementia risk and cognition in late-life. Improved prevention and treatment of CVRFs across the life course may be important to reduce health disparities for dementia.

Associations of Microvascular Dysfunction with Mild Cognitive Impairment and Cognitive Function Among Rural-Dwelling Older Adults in China

BACKGROUND

Microvascular dysfunction (MVD) may contribute to cognitive impairment and Alzheimer's disease, but evidence is limited.

OBJECTIVE

To investigate the association of composite and organ-specific MVD burden with mild cognitive impairment (MCI) and cognition among rural-dwelling Chinese older adults.

METHODS

In this population-based cross-sectional study, we assessed MVD makers using optical coherence tomographic angiography for retinal microvasculature features, brain magnetic resonance imaging scans for cerebral small vessel disease (CSVD), and serum biomarkers for MVD. A composite MVD score was generated from the aforementioned organ-specific parameters. We used a neuropsychological test battery to assess memory, verbal fluency, attention, executive function, and global cognitive function. MCI, amnestic MCI (aMCI), and non-amnestic MCI (naMCI) were diagnosed following the Petersen's criteria. Data was analyzed with the linear and logistic regression models.

RESULTS

Of the 274 dementia-free participants (age≥65 years), 56 were diagnosed with MCI, including 47 with aMCI and 9 with naMCI. A composite MVD score was statistically significantly associated with an odds ratio (OR) of 2.70 (95% confidence interval 1.12-6.53) for MCI and β-coefficient of -0.29 (-0.48--0.10) for global cognitive score after adjustment for socio-demographics, lifestyle factors, APOE genotype, the Geriatric Depression Scale score, serum inflammatory biomarkers, and cardiovascular comorbidity. A composite score of retinal microvascular morphology was associated with a multivariable-adjusted OR of 1.72 (1.09-2.73) for MCI and multivariable-adjusted β-coefficient of -0.11 (-0.22--0.01) for global cognitive score. A composite CSVD score was associated with a lower global cognitive score (β= -0.10; -0.17--0.02).

CONCLUSION

Microvascular dysfunction, especially in the brain and retina, is associated with MCI and poor cognitive function among rural-dwelling older adults.

Multimorbidity pattern and risk of dementia in later life: an 11-year follow-up study using a large community cohort and linked electronic health records

BACKGROUND

Several long-term chronic illnesses are known to be associated with an increased risk of dementia independently, but little is known how combinations or clusters of potentially interacting chronic conditions may influence the risk of developing dementia.

METHODS

447 888 dementia-free participants of the UK Biobank cohort at baseline (2006-2010) were followed-up until 31 May 2020 with a median follow-up duration of 11.3 years to identify incident cases of dementia. Latent class analysis (LCA) was used to identify multimorbidity patterns at baseline and covariate adjusted Cox regression was used to investigate their predictive effects on the risk of developing dementia. Potential effect moderations by C reactive protein (CRP) and Apolipoprotein E (APOE) genotype were assessed via statistical interaction.

RESULTS

LCA identified four multimorbidity clusters representing Mental health, Cardiometabolic, Inflammatory/autoimmune and Cancer-related pathophysiology, respectively. Estimated HRs suggest that multimorbidity clusters dominated by Mental health (HR=2.12, p<0.001, 95% CI 1.88 to 2.39) and Cardiometabolic conditions (2.02, p<0.001, 1.87 to 2.19) have the highest risk of developing dementia. Risk level for the Inflammatory/autoimmune cluster was intermediate (1.56, p<0.001, 1.37 to 1.78) and that for the Cancer cluster was least pronounced (1.36, p<0.001, 1.17 to 1.57). Contrary to expectation, neither CRP nor APOE genotype was found to moderate the effects of multimorbidity clusters on the risk of dementia.

CONCLUSIONS

Early identification of older adults at higher risk of accumulating multimorbidity of specific pathophysiology and tailored interventions to prevent or delay the onset of such multimorbidity may help prevention of dementia.

Impact of CPAP Therapy Adherence on Global Cognition in Patients with Moderate to Severe Obstructive Sleep Apnea: A One-Year Follow-Up

Background: Obstructive sleep apnea increases (OSA) cognitive impairment risk. The objective of this study was to determine the impact of continuous positive airway pressure (CPAP) adherence on global cognition using the Montreal Cognitive Assessment questionnaire (MoCA). Materials and Methods: Thirty-four new patients diagnosed with moderate or severe OSA (apnea-hypopnea index AHI ≥ 15 events/h) from the CPAP group were compared with thirty-one moderate to severe OSA patients from the no-CPAP group. In addition, all patients completed the MoCA test, a patient health questionnaire (PHQ-9) for depressive symptoms, and a generalized anxiety questionnaire (GAD-7) for anxiety symptoms, at baseline, after 6 months, and after 1 year. Results: At baseline, there were no significant differences between the two groups regarding total MoCA scores, 20.9 ± 3.5 CPAP group to 19.7 ± 2.9 no-CPAP group (p = 0.159), PHQ-9 (p = 0.651), and GAD-7 (p = 0.691). After one year, improvement was observed for a total MoCA score of 22.7 ± 3.5 (p < 0.001) for the CPAP group, and significant variance of score between groups was more accentuated for delayed recall and attention (p < 0.001) sub-topic. Moreover, PHQ-9, GAD-7 scores, and the Epworth Sleepiness Scale (ESS) decreased significantly (p < 0.001) after CPAP therapy. The MoCA score was significantly correlated with years of education (r = 0.74, p < 0.001) and had a negative correlation with body mass index (BMI) (r = -0.34), ESS (r = -0.30) and PHQ-9 (r = -0.34). Conclusions: One year of CPAP adherence improved global cognition associated with OSA.

Is metformin neuroprotective against diabetes mellitus-induced neurodegeneration? An updated graphical review of molecular basis

Diabetes mellitus (DM) is a metabolic disease that activates several molecular pathways involved in neurodegenerative disorders. Metformin, an anti-hyperglycemic drug used for treating DM, has the potential to exert a significant neuroprotective role against the detrimental effects of DM. This review discusses recent clinical and laboratory studies investigating the neuroprotective properties of metformin against DM-induced neurodegeneration and the roles of various molecular pathways, including mitochondrial dysfunction, oxidative stress, inflammation, apoptosis, and its related cascades. A literature search was conducted from January 2000 to December 2022 using multiple databases including Web of Science, Wiley, Springer, PubMed, Elsevier Science Direct, Google Scholar, the Core Collection, Scopus, and the Cochrane Library to collect and evaluate peer-reviewed literature regarding the neuroprotective role of metformin against DM-induced neurodegenerative events. The literature search supports the conclusion that metformin is neuroprotective against DM-induced neuronal cell degeneration in both peripheral and central nervous systems, and this effect is likely mediated via modulation of oxidative stress, inflammation, and cell death pathways.

Ambient air pollution and clinical dementia: systematic review and meta-analysis

OBJECTIVE

To investigate the role of air pollutants in risk of dementia, considering differences by study factors that could influence findings.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

EMBASE, PubMed, Web of Science, Psycinfo, and OVID Medline from database inception through July 2022.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies that included adults (≥18 years), a longitudinal follow-up, considered US Environmental Protection Agency criteria air pollutants and proxies of traffic pollution, averaged exposure over a year or more, and reported associations between ambient pollutants and clinical dementia. Two authors independently extracted data using a predefined data extraction form and assessed risk of bias using the Risk of Bias In Non-randomised Studies of Exposures (ROBINS-E) tool. A meta-analysis with Knapp-Hartung standard errors was done when at least three studies for a given pollutant used comparable approaches.

RESULTS

2080 records identified 51 studies for inclusion. Most studies were at high risk of bias, although in many cases bias was towards the null. 14 studies could be meta-analysed for particulate matter <2.5 µm in diameter (PM2.5). The overall hazard ratio per 2 μg/m3 PM2.5 was 1.04 (95% confidence interval 0.99 to 1.09). The hazard ratio among seven studies that used active case ascertainment was 1.42 (1.00 to 2.02) and among seven studies that used passive case ascertainment was 1.03 (0.98 to 1.07). The overall hazard ratio per 10 μg/m3 nitrogen dioxide was 1.02 ((0.98 to 1.06); nine studies) and per 10 μg/m3 nitrogen oxide was 1.05 ((0.98 to 1.13); five studies). Ozone had no clear association with dementia (hazard ratio per 5 μg/m3 was 1.00 (0.98 to 1.05); four studies).

CONCLUSION

PM2.5 might be a risk factor for dementia, as well as nitrogen dioxide and nitrogen oxide, although with more limited data. The meta-analysed hazard ratios are subject to limitations that require interpretation with caution. Outcome ascertainment approaches differ across studies and each exposure assessment approach likely is only a proxy for causally relevant exposure in relation to clinical dementia outcomes. Studies that evaluate critical periods of exposure and pollutants other than PM2.5, and studies that actively assess all participants for outcomes are needed. Nonetheless, our results can provide current best estimates for use in burden of disease and regulatory setting efforts.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021277083.