Cognitive Decline In Older Adults Research Articles

A Novel Dual-Language Touch-Screen Intervention to Slow Down Cognitive Decline in Older Adults: A Randomized Controlled Trial

Abstract Background and Objectives Bilingualism has been suggested to protect older adults from cognitive aging and delay the onset of dementia. However, no studies have systematically explored bilingual usage as a tool to mitigate age-related cognitive decline. We developed the Dual-Language Intervention in Semantic memory – Computerized (DISC), a novel cognitive training program with three training tasks (object categorization, verbal fluency, and utility of things) designed specifically for older adults that featured two modes: single-language (SL) exposure mode and dual-language (DL) exposure mode. Research Design and Methods The final sample included 50 cognitively healthy (CH; 33 female, Mage=72.93 years, range=53.08 – 87.43 years) and 48 cognitively impaired (CI; 35 female, Mage=80.93 years, range=62.31 – 96.67 years) older adults, randomly assigned them into one of three groups: SL group, DL group, and control group (no training). Participants in SL and DL groups used DISC in either SL mode (i.e., training instructions were spoken in only one language throughout the entire training) or DL mode (i.e., training instructions alternated between two languages) respectively over 24 sessions. Participants in the control group were asked to continue with their normal daily activities (e.g., playing bingo, reading newspapers). Results For CH older adults, we found significant improvements in the Rey Auditory Verbal Learning Test (RAVLT) Trial 5 score, and the Clock Drawing Test score, in the DL group but not in the SL and control groups post-training compared to pre-training. For CI older adults, there was a delayed improvement in the RAVLT Trial 1, 6 months later. Discussion and Implications Our findings provided novel evidence that implementing DL cognitive training benefits CH older adult’s late verbal learning and visuospatial construction skills, and a delayed improvement in CI older adults’ early verbal learning abilities.

Implications of helplessness in depression: diagnosing mild cognitive impairment and analyzing its effects on cognitive decline in older adults

Implications of helplessness in depression: diagnosing mild cognitive impairment and analyzing its effects on cognitive decline in older adults

Association between untreated and treated blood pressure levels and cognitive decline in community-dwelling middle-aged and older adults in China: a longitudinal study

BackgroundOptimal blood pressure (BP) levels to reduce the long-term risk of cognitive decline remains controversial. We aimed to investigate the association between BP and anti-hypertensive treatment status with cognitive decline in older adults.MethodsThis study used data from the China Health and Retirement Longitudinal Study. Cognitive function was assessed at year 2011, 2013, 2015, and 2018. Global cognitive Z-score was calculated as the average score of episodic memory and mental intactness. BP were measured at the first and second wave. Pulse pressure (PP) was calculated as systolic BP (SBP) minus diastolic BP. Cumulative BP was calculated as the area under the curve using BP measurements from 2011 to 2013. Linear mixed models were used to assess the longitudinal association between BP-related measurements and cognitive decline.ResultsWe included 11,671 participants (47.3% men and mean age 58.6 years). Individual with BP > 140/90 mm Hg or taking anti-hypertensive medication were independently associated with accelerated cognitive decline (β=-0.014, 95% CI: -0.020 to -0.007). Individuals with anti-hypertensive medication use, but with controlled SBP to less than 120 mm Hg did not have a significantly increased risk of cognitive decline compared with normotension (β=-0.003, 95% CI: -0.021 to 0.014). Individuals on anti-hypertensive treatment with PP of more than 70 mm Hg had a significantly higher risk of cognitive decline (β=-0.033, 95% CI: -0.045 to -0.020). Regardless of anti-hypertensive treatment status, both elevated baseline and cumulative SBP and PP were found to be independently associated with accelerated cognitive decline.ConclusionsCumulatively elevated SBP, PP and uncontrolled BP were associated with subsequent cognitive decline. Effectively controlling BP with anti-hypertensive treatment may be able to preserve cognitive decline in older adults.

The time course of motor and cognitive decline in older adults and their associations with brain pathologies: a multicohort study

Many studies have reported that impaired gait precedes cognitive impairment in older people. We aimed to characterise the time course of cognitive and motor decline in older individuals and the association of these declines with the pathologies of Alzheimer's disease and related dementias. This multicohort study used data from three community-based cohort studies (Religious Orders Study, Rush Memory and Aging Project, and Minority Aging Research Study, all in the USA). The inclusion criteria for all three cohorts were no clinical dementia at the time of enrolment and consent to annual clinical assessments. Eligible participants consented to post-mortem brain donation and had post-mortem pathological assessments and three or more repeated annual measures of cognition and motor functions. Clinical and post-mortem data were analysed using functional mixed-effects models. Global cognition was based on 19 neuropsychological tests, a hand strength score was based on grip and pinch strength, and a gait score was based on the number of steps and time to walk 8 feet and turn 360°. Brain pathologies of Alzheimer's disease and related dementias were assessed at autopsy. From 1994 to 2022, there were 1570 eligible cohort participants aged 65 years or older, 1303 of whom had cognitive and motor measurements and were included in the analysis. Mean age at death was 90·3 years (SD 6·3), 905 (69%) participants were female, and 398 (31%) were male. Median follow-up time was 9 years (IQR 5-11). On average, cognition was stable from 25 to 15 years before death, when cognition began to decline. By contrast, gait function and hand strength declined during the entire study. The combinations of pathologies of Alzheimer's disease and related dementias associated with cognitive and motor decline and their onsets of associations varied; only tau tangles, Parkinson's disease pathology, and macroinfarcts were associated with decline of all three phenotypes. Tau tangles were significantly associated with cognitive decline, gait function decline, and hand function decline (p<0·0001 for each); however, the association with cognitive decline persisted for more than 11 years before death, but the association with hand strength only began 3·57 years before death and the association with gait began 3·49 years before death. By contrast, the association of macroinfarcts with declining gait function began 9·25 years before death (p<0·0001) compared with 6·65 years before death (p=0·0005) for cognitive decline and 2·66 years before death (p=0·024) for decline in hand strength. Our findings suggest that average motor decline in older adults precedes cognitive decline. Macroinfarcts but not tau tangles are associated with declining gait function that precedes cognitive decline. This suggests the need for further studies to test if gait impairment is a clinical proxy for preclinical vascular cognitive impairment. National Institutes of Health.

The effects of computerized cognitive training in older adults' cognitive performance and biomarkers of structural brain aging.

Cognitive Training (CT) has been investigated as a means of delaying age-related cognitive decline in older adults. However, its impact on biomarkers of age-related structural brain atrophy has rarely been investigated, leading to a gap in our understanding of the linkage between improvements in cognition and brain plasticity. This study aimed to explore the impact of CT on cognitive performance and brain structure in older adults. 124 cognitively normal older adults recruited from two study sites were randomly assigned to either an adaptive CT (n=60) or a casual game training (Active Control, AC, n= 64). After 10 weeks of training, CT participants showed greater improvements in the overall cognitive composite score (Cohen's d=.66, p<.01) with non-significant benefits after 6 months from the completion of training (Cohen's d=.36, p=.094). The CT group showed significant maintenance of the caudate volume as well as significant maintained fractional anisotropy (FA) in the left Internal Capsule (IC) and in left Superior Longitudinal Fasciculus (SLF) compared to the AC group. The AC group displayed an age-related decrease in these metrics of brain structure. Results from this multi-site clinical trial demonstrate that the CT intervention improves cognitive performance and helps maintain caudate volume and integrity of white matter regions that are associated with cognitive control, adding to our understanding of the changes in brain structure contributing to changes in cognitive performance from adaptive CT.

Elevated blood homocysteine increases the risk of incident Motoric Cognitive Risk syndrome: A two cohort study.

Motoric Cognitive Risk (MCR) syndrome, a pre-dementia syndrome characterized by cognitive complaints and slow gait, may have an underlying vascular etiology. Elevated blood levels of homocysteine, a known vascular risk factor, have been linked to physical and cognitive decline in older adults, though the relationship with MCR is unknown. We aimed to identify the association between homocysteine and MCR risk. We examined the association between baseline homocysteine levels and incident MCR using Cox proportional hazard models in 1,826 community-dwelling older adults (55% female) from two cohorts (Einstein Aging Study [EAS] and Quebec Longitudinal Study on Nutrition and Successful Aging [NuAge]). We calculated hazard ratios (HR) with 95% confidence intervals (CI), for each cohort as well as stratified by sex and vascular disease/risk factors. Median follow-up time was 2.2 years in EAS and 3.0 years in NuAge. Individuals with elevated baseline homocysteine levels (> 14 µmol/L) had a significantly higher risk of incident MCR compared to those with normal levels in NuAge (HR 1.41, 95% CI = 1.01-1.97, p = .04), after adjusting for covariates. Our exploratory stratified analyses found that these associations were significant only in men with vascular disease/risk factors. Higher blood homocysteine levels are associated with increased risk of developing MCR in older adults, particularly in men with vascular disease or vascular risk factors.

Effects of Square Stepping Exercise on cognitive, physical, psychological, and group functioning in sedentary older adults: A center-based hybrid trial

BackgroundThe Square Stepping Exercise (SSE) is an exercise training program that integrates physical exercise and cognitive elements and can be conducted in a group setting. The potential of SSE in delaying cognitive decline in older adults is promising. However, the coronavirus pandemic has made it more difficult for older adults worldwide to exercise together in person. To address this issue, this study conducted a wholistic evaluation of the effects of a center-based hybrid SSE trial on cognitive, physical, psychological, and group functioning in sedentary older adults.MethodsA total of 93 older adults (19 men, 74 women) participated in the study. Fifty-eight participants (9 men, 49 women) completed center-based hybrid SSE sessions over 12 weeks under coronavirus pandemic circumstances, whereas other 35 participants in the control group maintained their current level of daily activities. Cognitive functions focused on executive functions assessed by the Stroop Color-Word Test (inhibition) and the Trail Marking Test (TMT) (set-shifting). Psychological and group functioning were assessed by the Subjective Vitality Scale and the Physical Activity Group Environment Questionnaire. Physical function was evaluated by measuring gait speeds. A repeated ANOVA was conducted on the measured variables separately for the intervention and control groups to focus on the change of participant’s performance over data collection points.ResultsOutcomes of the Stroop Color-Word Test and the TMT revealed that the hybrid SSE was highly effective in improving executive function. Stroop performance (correct trials) was significantly improved in the incongruent condition, as well as both TMT-A and -B over the intervention period in the intervention group. The hybrid SSE was also beneficial to improve physical (gait speed at usual pace and at the maximum pace) as well as psychological functioning (subjective vitality). Furthermore, SSE participants reported increased engagement with the SSE task, social communication, and increased bonding and closeness with their group members through the hybrid SSE.ConclusionsIn this study, hybrid SSE was found to be effective in enhancing cognitive, physical, psychological, and group functioning in sedentary older adults. The findings of this study are crucial to provide older adults with a safer and efficient option to exercise.

0456 Impact of Hypertension and Sleep-disordered Breathing on Cognitive Decline in Older Adults

0456 Impact of Hypertension and Sleep-disordered Breathing on Cognitive Decline in Older Adults

Gait speed and its associated factors among older black adults in Sub-Saharan Africa: Evidence from the WHO study on Global AGEing in older adults (SAGE).

Gait speed is an essential predictor of functional and cognitive decline in older adults. The study aimed to investigate the gait speed of older adults in Ghana and South Africa and to determine its associated factors, as the Sub-Saharan representatives in the World Health Organization's Study on Global AGEing in Older Adults (SAGE). A secondary analysis of data from the SAGE study which consists of nationally representative data involving participants aged ≥50+ years with smaller samples of younger adults aged 18-49 years in Ghana and South Africa was conducted. SAGE study employed a multistage, stratified clustered sample design and involved the use of a standardised questionnaire to obtain participants' (n = 5808) demographic, anthropometric and gait speed information. The standard 4 metre-gait speed was used. Median gait speed for the study group, which comprised African/Black participants aged ≥50+ years was 0.769(Q1 = 0.571, Q3 = 0.952)m/s for males and 0.667 (Q1 = 0.500,Q3 = 0.833)m/s for females. For every unit increase in age, the odds of being in a higher-ranked gait speed category was 0.96(95%CI 0·96, 0·97, p<0.001) times that of the previous age. Females had odds of 0.55 (95%CI 0.50, 0.61, p<0.001) of recording higher gait speed, as compared to males. Rural dwellers had odds of 1.43 (95%CI 1.29, 1.58, p < 0.001) of being in a higher-ranked category of gait speed compared to urban dwellers. Underweight (OR = 0.85, 95%C1 = 0.73-1.00, p<0.05) and obesity (OR = 0.53, 95%CI = 0.46-0.61, p<0.001) were associated with slower gait speed. Amongst functional indices, the World Health Organization Disability Assessment Schedule (WHODAS) score was the biggest determinant of gait speed. Having a "Severe/Extreme" WHODAS score had the strongest association with gait speed (OR = 0.18, 95%CI = 0.14-0.23, p<0.001). These gait speed results provide an essential reference for older adults' care in Ghana and South Africa.

Depressive symptoms and cognitive decline in older adults.

Few studies have examined the impact of late-life depression trajectories on specific domains of cognitive function. This study aims to delineate how different depressive symptom trajectories specifically affect cognitive function in older adults. Prospective longitudinal cohort study. Australia and the United States of America. In total, 11,035 community-dwelling older adults with a mean age of 75 years. Depressive trajectories were modelled from depressive symptoms according to annual Centre for Epidemiological Studies Depression Scale 10 (CES-D-10) surveys. Four trajectories of depressive symptoms were identified: low ("nondepressed"), consistently mild ("subthreshold depression"), consistently moderate ("persistent depression"), and initially low but increasing ("emerging depression"). Global cognition (Modified Mini-Mental State Examination [3MS]), verbal fluency (Controlled Oral Word Association Test [COWAT]), processing speed (Symbol Digit Modalities Test [SDMT]), episodic memory (Hopkins Verbal Learning Test - Revised [HVLT-R]), and a composite z-score were assessed over a subsequent median 2 years. Subthreshold depression predicted impaired performance on the SDMT (Cohen's d -0.04) and composite score (-0.03); emerging depression predicted impaired performance on the SDMT (-0.13), HVLT-R (-0.09), 3 MS (-0.08) and composite score (-0.09); and persistent depression predicted impaired performance on the SDMT (-0.08), 3 MS (-0.11), and composite score (-0.09). Depressive symptoms are associated with later impaired processing speed. These effects are small. Diverse depression trajectories have different impacts on cognitive function.

Sex Differences in the Association Between LDL/HDL with Cognitive Decline in Older Adults: National Health and Nutrition Examination Survey.

Lipids have a significant impact on the development and functioning of the nervous system, but the sex differences between the association of LDL/HDL, which reflects lipid metabolic status, and cognitive impairment remains unclear. We aimed to determine if there were sex differences between the association of LDL/HDL and cognitive function in US older adults. This population-based cross-sectional study used data from the National Health and Nutrition Examination Survey (NHANES) 2011-2012 and 2013-2014 cycles. The main outcome was poor cognitive performance defined by the Digit Symbol Substitution Test (DSST) < 34 based on published literature. A total of 1,225 participants were included in the study, with a cognitive impairment incidence of 25.6% (314/1,225). Multivariate regression models demonstrated a significant association between cognitive decline and each 1-unit increase in LDL/HDL, after adjusting for all covariates (adjusted odds ratio [OR] = 1.36, 95% confidence interval [CI]: 1.11-1.67). Furthermore, subgroup analysis revealed an interaction between LDL/HDL and cognitive impairment in sex subgroups. LDL/HDL was associated with cognitive impairment in the US older adult population in adjusted models, although the significance of this association was not observed in females.

The Postoperative Effects of Anesthesia Exposure on Cognitive Decline in Older Adults: A Narrative Review.

As modern medicine continues to make strides in effective surgical treatments, we must also consider the critical impact of anesthesia on neuropsychological outcomes. Recent evidence suggests that anesthesia exposure may be a risk factor for postoperative cognitive decline and the eventual development of dementia. To explore the vulnerability of the aging brain in the context of anesthesia exposure in surgery, studies will be reviewed, and pertinent findings will be highlighted and explored to better understand risks and possible factors that need to be considered when contemplating surgery. A narrative review was conducted using a combination of MEDLINE and APA PsycINFO databases to shed light on themes across studies assessing general trends regarding the influence of anesthesia on postoperative cognitive decline. A search of relevant literature identified 388 articles. Excluding results outside the parameters of this study, the review includes quality assessments for 24 articles. While findings are inconclusive, suggestions for further investigation into the relationship between anesthesia exposure and increased risk for postoperative cognitive decline are discussed, in addition to factors that may allow for greater informed disclosure of potential risks of anesthesia in older adults.

Frail hypertensive older adults with prediabetes and chronic kidney disease: insights on organ damage and cognitive performance - preliminary results from the CARYATID study

BackgroundHypertension and chronic kidney disease (CKD) pose significant public health challenges, sharing intertwined pathophysiological mechanisms. Prediabetes is recognized as a precursor to diabetes and is often accompanied by cardiovascular comorbidities such as hypertension, elevating the risk of pre-frailty and frailty. Albuminuria is a hallmark of organ damage in hypertension amplifying the risk of pre-frailty, frailty, and cognitive decline in older adults. We explored the association between albuminuria and cognitive impairment in frail older adults with prediabetes and CKD, assessing cognitive levels based on estimated glomerular filtration rate (eGFR).MethodsWe conducted a study involving consecutive frail older patients with hypertension recruited from March 2021 to March 2023 at the ASL (local health unit of the Italian Ministry of Health) of Avellino, Italy, followed up after three months. Inclusion criteria comprised age over 65 years, prior diagnosis of hypertension without secondary causes, prediabetes, frailty status, Montreal Cognitive Assessment (MoCA) score < 26, and CKD with eGFR > 15 ml/min.Results237 patients completed the study. We examined the association between albuminuria and MoCA Score, revealing a significant inverse correlation (r: 0.8846; p < 0.0001). Subsequently, we compared MoCA Score based on eGFR, observing a significant difference (p < 0.0001). These findings were further supported by a multivariable regression analysis, with albuminuria as the dependent variable.ConclusionsOur study represents the pioneering effort to establish a significant correlation between albuminuria and eGFR with cognitive function in frail hypertensive older adults afflicted with prediabetes and CKD.

Speech Biomarkers of Cognitive Decline in Older Adults (P2-9.011)

Speech Biomarkers of Cognitive Decline in Older Adults (P2-9.011)

Intertwined depressive and cognitive trajectories and the risk of dementia and death in older adults: a competing risk analysis

BackgroundDepressive symptoms and cognitive impairment often interact, rendering their associations controversial. To date, their joint trajectories and associations with dementia and death remain underexplored.AimsTo explore the interactions between depressive symptoms...

Cognitive Decline in Older Adults with Schizophrenia-Bipolar Spectrum Disorder

Mr. S is a 67-year-old man with psychiatric history of an unspecified psychotic disorder (schizophrenia vs schizoaffective disorder vs bipolar I disorder) and medical history of hypertension and hyperlipidemia who presented to the emergency department (ED) for inability to care for self after being picked up by emergency medical services (EMS) while wandering outside. Psychiatry was consulted due to a chart history of bipolar I disorder with concern for active mania given disorganization and agitation. On chart review, the patient had seven ED visits in two months prior to the current presentation, all for wandering. The patient was born in Jamaica, attended college, and worked as a paralegal before repeated hospitalizations for mania and/or psychosis. His mid-life history is unclear, but for the last 15+ years he was living in a group home without any hospitalizations. He was maintained on a stable regimen of clozapine, lithium, and valproic acid, until an episode of acute psychosis in 2015. Afterwards, he had 5+ admissions between 2017 and 2021 for altered mental status with pre-renal acute kidney injuries & lithium toxicity. After a particularly severe admission for lethargy in 2021, with creatinine increase to 2.9, clozapine and lithium were discontinued, and the patient has since remained on a regimen of valproic acid 500mg BID and haloperidol 15mg BID. On exam in the ED, he was awake, alert, with no evidence of head injury, and moving all extremities symmetrically and purposefully; his mood was “melancholy,” affect flat, thought process ruminative and goal directed. He endorsed passive suicidal ideation, exhibited paranoid delusions about family and staff, and denied any hallucinations. Urine toxicology screen was negative for illicit substances and showed an undetectable valproic acid level. No acute abnormalities were found on a non-contrast head CT, and non-specific white matter abnormalities and volume loss were noted on an MRI one year prior. He was admitted to a general psychiatric inpatient unit after 48 hours in the ED, where he was stabilized on home valproic acid and haloperidol with the addition of aripiprazole for mood and negative symptoms. Even once his psychiatric symptoms stabilized, the patient required considerable nursing support for completion of activities of daily living, with marked memory impairments. He scored a total of 16/30 on the Montreal Cognitive Assessment (MoCA), with impairments in executive function, language, and delayed recall. Occupational therapy (OT) evaluation using the Kohlman Evaluation of Living Skills demonstrated a need for assistance in all five domains of daily living with a recommendation for 24/7 assistance and a secure environment given memory loss and cognitive deficits. A hearing was held to assign his sister legal guardianship, and the patient was discharged to a skilled nursing facility with a secure unit after a total of 56 days of inpatient hospitalization.

Effect of visual impairment on subjective cognitive decline in older adults: a cross-sectional study in China

ObjectivePeople with visual impairment have more functional limitations associated with subjective cognitive decline (SCD), and those with SCD are extremely susceptible to transitioning to irreversible cognitive impairment. This study aimed...

Association of dietary inflammation with tooth loss and cognitive decline in older adults from cross-sectional data: The moderated role of albumin

ObjectiveGrowing evidence suggests a potential connection between tooth loss and cognitive function in recent years. Increasing studies have focused on their inter-relationship, however, the underlying mechanism has yet to be fully elucidated. Few studies have considered the role of dietary inflammation and serum albumin in the association between tooth loss and cognitive function. Therefore, the aim of this study was to explore the role of dietary inflammation and serum albumin in the association between tooth loss and cognitive impairment. MethodsA sample of 1,009 US adults from the National Health and Nutrition Examination Survey (NHANES) provided data on oral condition, cognitive function, dietary intake, and serum tests. The association between tooth loss (exposure variable) and cognitive function (outcome variable) was assessed by linear regression. Furthermore, a moderated mediation model was established to examine the influence of dietary inflammation on the association between tooth loss and cognitive tests, and the visualization of the moderating effect of serum albumin concentration was displayed through the Johnson-Neyman curve. ResultsParticipants with impaired dentition had worse cognitive function and a higher Dietary Inflammation Index (DII). DII was highly correlated with Immediate Recall Test (IR), Animal Fluency Test (AFT), and Digit Symbol Substitution Test (DSST), which mediated 16.46 %, 14.41 % and 11.28 % of the effect between tooth loss and cognitive functions. Additionally, the relationship between DII and DSST was moderated by serum albumin concentration. ConclusionTooth loss was associated with cognitive function which was affected by pro-inflammatory dietary patterns and serum albumin level. Clinical significanceThis study presents evidence for dentists that dietary pattern change due to tooth loss plays a role in cognitive deterioration, which can also be moderated by serum albumin level. Therefore, the preservation of natural teeth is important for cognitive function, especially in an immunocompromised population with decreased serum albumin concentrations.

Change in cardiovascular health and rate of cognitive decline in older adults: a 15-year population-based study

BackgroundPrevious research on associations between cardiovascular health, measured at a single timepoint, and rate of age-related cognitive decline shows divergent findings dependent on the participants’ age and the health metric studied. The aim of this study was to add to the knowledge in this field by investigating whether change in cardiovascular health, assessed with Life’s Simple 7 (LS7) score, is associated with rate of cognitive change in young-old and old-old adults.MethodsThe study included 1022 participants aged ≥ 60 years from the Swedish National Study on Aging and Care-Kungsholmen (SNAC-K), who underwent repeated neuropsychological testing (episodic memory, semantic memory, verbal fluency, and perceptual speed) across up to 15 years. LS7, composed of seven cardiovascular health metrics (smoking, diet, physical activity, body mass index, plasma glucose, total serum cholesterol, and blood pressure), was assessed at baseline and at the 6-year follow-up. Change in LS7 was calculated as the difference between baseline and 6 years (range − 5 to 8 points) and categorised into worse (−5 to −2 points), stable (−1 to 1 points), and improved (2 to 8 points). Change in cognitive performance as a function of LS7 change categories was estimated using linear mixed-effects models.ResultsParticipants were classified as stable (67.1%), improved (21.0%), or worse (11.8%) according to changes in LS7 score. Both the worse and improved categories were associated with faster cognitive decline. Age-stratified analyses revealed that worsening of LS7 was clearly associated with faster cognitive decline in the old-old (≥ 78 years), whereas improvement tended be associated with faster cognitive decline in the young-old (< 78 years) group.ConclusionsChange in cardiovascular health in old age may lead to accelerated cognitive decline, particularly in late senescence. These results suggest that it is important to monitor and maintain cardiovascular health status in very old adults.

Association between hippocampal microglia, AD and LATE-NC, and cognitive decline in older adults.

This study investigates the relationship between microglia inflammation in the hippocampus, brain pathologies, and cognitive decline. Participants underwent annual clinical evaluations and agreed to brain donation. Neuropathologic evaluations quantified microglial burden in the hippocampus, amyloid beta (Aβ), tau tangles, and limbic age-related transactive response DNA-binding protein 43 (TDP-43) encephalopathy neuropathologic changes (LATE-NC), and other common brain pathologies. Mixed-effect and linear regression models examined the association of microglia with a decline in global and domain-specific cognitive measures, and separately with brain pathologies. Path analyses estimated direct and indirect effects of microglia on global cognition. Hippocampal microglia were associated with a faster decline in global cognition, specifically in episodic memory, semantic memory, and perceptual speed. Tau tangles and LATE-NC were independently associated with microglia. Other pathologies, including Aβ, were not related. Regional hippocampal burden of tau tangles and TDP-43 accounted for half of the association of microglia with cognitive decline. Microglia inflammation in the hippocampus contributes to cognitive decline. Tau tangles and LATE-NC partially mediate this association.