Predictors of cognitive aging profiles over 15 years: A longitudinal population-based study.

The present study aimed to characterize profiles of cognitive aging and how these can be predicted from interindividual differences in demographic, lifestyle, health, and genetic factors. The participants were 1,966 older adults (mean baseline age = 71.6 years; 62.9% female), free from dementia at baseline and with at least two cognitive assessments over the 15-year follow-up, from the population-based Swedish National Study on Aging and Care in Kungsholmen. The cognitive assessment comprised tests of semantic and episodic memory, letter and category fluency, perceptual speed, and executive function. First, we estimated the level and change within each of the cognitive domains with linear mixed effect models, based on which we grouped our sample into participants with "maintained high cognition," "moderate cognitive decline," or "accelerated cognitive decline." Second, we analyzed determinants of group membership within each cognitive domain with multinomial logistic regression. Third, group memberships within each cognitive domain were used to derive general cognitive aging profiles with latent class analysis. Fourth, the determinants of these profile memberships were analyzed with multinomial logistic regression. Follow-up analyses targeted profiles and predictors specifically related to the rate of cognitive change. We identified three latent profiles of overall cognitive performance during the follow-up period with 31.6% of the sample having maintained high cognition, 50.6% having moderate cognitive decline, and 17.8% having accelerated cognitive decline. In multiadjusted analyses, maintained high cognition was predicted by female sex, higher education, and faster walking speed. Smoking, loneliness, and being an ε4 carrier were associated with a lower likelihood of maintained high cognition. Higher age, diagnosis of diabetes, depression, and carrying the apolipoprotein E ε4 allele increased the likelihood of accelerated cognitive decline. Factors at baseline that could significantly predict profile membership within the specific cognitive domains included age, sex, years of education, walking speed, diabetes, and the ε4 allele. Of note, these factors differed across cognitive domains. In sum, we identified demographic, lifestyle, health, and genetic factors of interindividual differences in domain-specific and general cognitive aging profiles, some of which are modifiable. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

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 ß-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: ß-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 cognitive reserve with transitions across cognitive states and death in older adults: A 15-year follow-up study.

INTRODUCTION: We investigated the association of cognitive reserve (CR) with transitions across cognitive states and death. METHODS: This population-based cohort study included 2631 participants (age ≥60 years) who were dementia-free at baseline and regularly examined up to 15 years. Data were analyzed using the Markov multistate models. RESULTS: Each 1-point increase in the composite CR score (range: -4.25 to 3.46) was significantly associated with lower risks of transition from normal cognition to cognitive impairment, no dementia (CIND) (multivariable-adjusted hazards ratio = 0.78; 95% confidence interval = 0.72-0.85) and death (0.85; 0.79-0.93), and from CIND to death (0.82; 0.73-0.91), but not from CIND to normal cognition or dementia. A greater composite CR score was associated with a lower risk of transition from CIND to death in people aged 60-72 but not in those aged ≥ 78 years. DISCUSSION: CR contributes to cognitive health by delaying cognitive deterioration in the prodromal phase of dementia. HIGHLIGHTS: We use Markov multistate model to examine the association between cognitive reserve and transitions across cognitive states and death. A great cognitive reserve contributes to cognitive health by delaying cognitive deterioration in the prodromal phase of dementia. A great cognitive reserve is associated with a lower risk of transition from cognitive impairment, no dementia to death in people at the early stage of old age, but not in those at the late stage of old age.

Social health and subsequent cognitive functioning in people aged 50 years and older: examining the mediating roles of depressive symptoms and inflammatory biomarkers in two European longitudinal studies.

BACKGROUND: Social health markers, including marital status, contact frequency, network size, and social support, have been shown to be associated with cognition. However, the mechanisms underlying these associations remain poorly understood. We investigated whether depressive symptoms and inflammation mediated associations between social health and subsequent cognition. METHODS: In the English Longitudinal Study of Ageing (ELSA), a nationally representative longitudinal study in England, UK, we sampled 7136 individuals aged 50 years or older living in private households without dementia at baseline or at the intermediate mediator assessment timepoint, who had recorded information on at least one social health marker and potential mediator. We used four-way decomposition to examine to what extent depressive symptoms, C-reactive protein, and fibrinogen mediated associations between social health and subsequent standardised cognition (verbal fluency and delayed and immediate recall), including cognitive change, with slopes derived from multilevel models (12-year slope). We examined whether findings were replicated in the Swedish National Study on Aging and Care in Kungsholmen (SNAC-K), a population-based longitudinal study in Sweden, in a sample of 2604 individuals aged 60 years or older living at home or in institutions in Kungsholmen (central Stockholm) without dementia at baseline or at the intermediate mediator assessment timepoint (6-year slope). Social health exposures were assessed at baseline, potential mediators were assessed at an intermediate timepoint (wave 2 in ELSA and 6-year follow-up in SNAC-K); cognitive outcomes were assessed at a single timepoint (wave 3 in ELSA and 12-year follow-up in SNAC-K), and cognitive change (between waves 3 and 9 in ELSA and between 6-year and 12-year follow-ups in SNAC-K). FINDINGS: The study sample included 7136 participants from ELSA, of whom 3962 (55·5%) were women and 6934 (97·2%) were White; the mean baseline age was 63·8 years (SD 9·4). Replication analyses included 2604 participants from SNAC-K, of whom 1604 (61·6%) were women (SNAC-K did not collect ethnicity data); the mean baseline age was 72·3 years (SD 10·1). In ELSA, we found indirect effects via depressive symptoms of network size, positive support, and less negative support on subsequent verbal fluency, and of positive support on subsequent immediate recall (pure indirect effect [PIE] 0·002 [95% CI 0·001-0·003]). Depressive symptoms also partially mediated associations between less negative support and slower decline in immediate recall (PIE 0·001 [0·000-0·002]) and in delayed recall (PIE 0·001 [0·000-0·002]), and between positive support and slower decline in immediate recall (PIE 0·001 [0·000-0·001]). We did not observe mediation by inflammatory biomarkers. Findings of mediation by depressive symptoms in the association between positive support and verbal fluency and between positive support and change in immediate recall were replicated in SNAC-K. INTERPRETATION: The findings of this study provide new insights into mechanisms linking social health with cognition, suggesting that associations between interactional aspects of social health, especially social support, and cognition are partly underpinned by depressive symptoms. FUNDING: EU Joint Programme-Neurodegenerative Disease Research (JPND) and Alzheimer's Society. TRANSLATION: For the Swedish translation of the abstract see Supplementary Materials section.

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 (ß = -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.

Long-term exposure to transportation noise in relation to global cognitive decline and cognitive impairment: Results from a Swedish longitudinal cohort.

BACKGROUND AND AIMS: Transportation noise is an environmental exposure with mounting evidence of adverse health effects. Besides the increased risk of cardiovascular and metabolic diseases, recent studies suggest that long-term noise exposure might accelerate cognitive decline in older age. We examined the association between transportation noise and cognitive function in a cohort of older adults. METHODS: The present study is based on 2594 dementia-free participants aged 60 + years from the Swedish National study on Aging and Care in Kungsholmen (SNAC-K). Global cognition score and CIND (cognitive impairment, no dementia) were assessed with a comprehensive neuropsychological battery at baseline and up to 16 years. Residential transportation noise resulting from road traffic, railway, and aircraft were estimated at the most exposed façade and the time-weighted average exposure was assessed. Linear mixed-effect models were used to assess the effect of long-term traffic noise exposure on the rate of change in global cognition score. Hazard ratios (HRs) and 95 % confidence intervals (CIs) of CIND by transportation noise exposure were obtained with Cox proportional hazard models. RESULTS: Global cognition score decreased at an average rate of -0.041 (95 %CI -0.043, -0.039) per year. Aircraft noise was associated with a 0.007 (per 10 dB Lden; 95 %CI -0.012, -0.001) faster annual rate of decline. Global cognition score seems to be not affected by road traffic and railway noise. During the follow-up, 422 (21 %) participants developed CIND. A 10-dB Lden difference in exposure to aircraft and railway noise was associated with a 16 % (HR 1.16, 95 %CI 0.91, 1.49) and 26 % (HR 1.26, 95 %CI 1.01, 1.56) increased hazard of CIND in the multi-pollutant model, respectively. No association was found for road traffic (HR 1.00, 95 %CI 0.83, 1.21). CONCLUSIONS: Transportation noise was linked to cognitive impairment and faster cognitive decline among older adults. Future studies are warranted to confirm our results.

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

BACKGROUND: Previous 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. METHODS: The 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. RESULTS: Participants 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. CONCLUSIONS: Change 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.

Cardiovascular health and rate of cognitive decline in preclinical dementia: A 12-year population-based study.

OBJECTIVE: We investigated whether vascular risk factors (VRFs), assessed with Life's Simple 7 (LS7), are associated with the rate of cognitive decline in the years preceding a dementia diagnosis. METHOD: This study included 1,449 stroke-free participants aged ≥60 years from the Swedish National Study on Aging and Care in Kungsholmen, who underwent repeated neuropsychological testing (episodic memory, semantic memory, verbal fluency, perceptual speed) across 12 years. The LS7 score, assessed at baseline, included smoking, diet, physical activity, body mass index, plasma glucose, total cholesterol, and blood pressure. Preclinical dementia was defined as being dementia-free at baseline and diagnosed with dementia during follow-up. Level and change in cognitive performance as a function of LS7 category (poor vs. intermediate to optimal) and future dementia status were estimated using linear mixed-effect models. RESULTS: Participants who later developed dementia had, on average, a poorer LS7 score compared to those who remained dementia-free. For individuals aged 60-72 years, poor diet was associated with accelerated decline in perceptual speed (ß = -0.05, 95% CI [-0.08, -0.02]), and a poor glucose score was associated with faster rates of verbal fluency (ß = -0.019, 95% CI [-0.09, -0.01]) and global cognitive (ß = -0.028, 95% CI [-0.06, 0.00]) decline in the preclinical dementia group. CONCLUSIONS: VRFs exacerbate rate of cognitive decline in the years preceding a dementia diagnosis. This effect was most pronounced in young-old age and primarily driven by diet and glucose. The effect of VRFs may be especially detrimental for cognitive decline trajectories of individuals with impending dementia. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Association of mild and complex multimorbidity with structural brain changes in older adults: A population-based study.

INTRODUCTION: We quantified the association of mild (ie, involving one or two body systems) and complex (ie, involving ≥3 systems) multimorbidity with structural brain changes in older adults. METHODS: We included 390 dementia-free participants aged 60+ from the Swedish National Study on Aging and Care in Kungsholmen who underwent brain magnetic resonance imaging at baseline and after 3 and/or 6 years. Using linear mixed models, we estimated the association between multimorbidity and changes in total brain tissue, ventricular, hippocampal, and white matter hyperintensities volumes. RESULTS: Compared to non-multimorbid participants, those with complex multimorbidity showed the steepest reduction in total brain (ß*time -0.03, 95% CI -0.05, -0.01) and hippocampal (ß*time -0.05, 95% CI -0.08, -0.03) volumes, the greatest ventricular enlargement (ß*time 0.03, 95% CI 0.01, 0.05), and the fastest white matter hyperintensities accumulation (ß*time 0.04, 95% CI 0.01, 0.07). DISCUSSION: Multimorbidity, particularly when involving multiple body systems, is associated with accelerated structural brain changes, involving both neurodegeneration and vascular pathology. HIGHLIGHTS: Multimorbidity accelerates structural brain changes in cognitively intact older adults These brain changes encompass both neurodegeneration and cerebrovascular pathology The complexity of multimorbidity is associated with the rate of brain changes' progression.

Associations of Orthostatic Hypotension and Frailty With Dementia and Mortality in Older Adults: A Population-Based Cohort Study.

BACKGROUND: This study aimed to assess the associations of orthostatic hypotension (OH), in the presence or absence of frailty, with dementia and mortality in older adults. METHODS: We conducted a 15-year population-based cohort study including 2 703 baseline dementia-free individuals from the Swedish National Study on Aging and Care in Kungsholmen. At baseline, OH was defined as a decline in systolic/diastolic blood pressure ≥20/10 mm Hg 1 minute after standing up from a supine position. Frailty status was defined following Fried's frailty phenotype. Dementia was diagnosed following the Diagnostic and Statistical Manual of Mental Disorders-fourth edition criteria. Multistate flexible parametric survival models were used to estimate associations of OH and frailty with dementia and mortality. RESULTS: Robust people with OH (adjusted hazard ratio [HR] = 2.28; 95% confidence interval [CI] = 1.47-3.54) and frail people without OH (HR = 1.98; 95% CI = 1.40-2.82) or with OH (HR = 2.73; 95% CI = 1.82-4.10) had a higher dementia risk than OH-free and robust people. Moreover, frail people, independently of the presence of OH, had higher mortality rate than OH-free and robust people. In individuals who developed dementia during the follow-up period, neither OH nor frailty was significantly associated with mortality. CONCLUSIONS: Older adults with OH, whether robust or frail, may have a higher dementia risk than those without OH. Older adults with OH, when having frailty, may have a higher mortality rate than those without OH. The concurrent assessments of OH and frailty may provide prognostic values in terms of dementia and mortality risk in older adults.

Sleep disturbances and change in multiple cognitive domains among older adults: a multicenter study of five Nordic cohorts.

STUDY OBJECTIVES: We examined and compared cross-sectional and longitudinal associations between self-reported sleep disturbances and various cognitive domains in five separate Nordic European longitudinal aging studies (baseline N = 5631, mean age = 77.7, mean follow-up = 4.16 years). METHODS: Comparable sleep parameters across studies included reduced sleep duration/quality, insomnia symptoms (sleep latency, waking up at night, and early awakenings), short and long sleep duration, and daytime napping. The cognitive domains were episodic memory, verbal fluency, perceptual speed, executive functioning, and global cognition (aggregated measure). A series of mixed linear models were run separately in each study and then compared to assess the level and rate of change in cognitive functioning across each sleep disturbance parameter. Models were adjusted for age, sex, education, hypnotic usage, depressive symptoms, lifestyle factors, cardiovascular, and metabolic conditions. By using a coordinated analytic approach, comparable construct-level measurements were generated, and results from identical statistical models were qualitatively compared across studies. RESULTS: While the pattern of statistically significant results varied across studies, subjective sleep disturbances were consistently associated with worse cognition and steeper cognitive decline. Insomnia symptoms were associated with poorer episodic memory and participants sleeping less or more than 7-8 hours had a steeper decline in perceptual speed. In addition, daytime napping (>2 hours) was cross-sectionally and longitudinally associated with all examined cognitive domains. Most observed associations were study-specific (except for daytime napping), and a majority of association estimates remained significant after adjusting for covariates. CONCLUSION: This rigorous multicenter investigation further supports the importance of sleep disturbance, including insomnia, long and short sleep duration, and daytime napping on baseline cognitive functioning and rate of change among older adults. These sleep factors may be targeted in future lifestyle interventions to reduce cognitive decline.

Association of white matter hyperintensity accumulation with domain-specific cognitive decline: a population-based cohort study.

We investigated the association of load and accumulation of white matter hyperintensities (WMHs) with rate of cognitive decline. This population-based study included 510 dementia-free people (age ≥60 years) who had repeated measures of global and regional (lobar, deep, periventricular) WMHs up to 6 years (from 2001-2003 to 2007-2010) and repeated measures of cognitive function (episodic memory, semantic memory, category fluency, letter fluency, executive function, perceptual speed) up to 15 years (from 2001-2004 to 2016-2019). We found that greater baseline loads of global and regional WMHs were associated with faster decline in letter fluency, perceptual speed, and global cognition. Furthermore, faster accumulation of global, deep, and periventricular WMHs was related to accelerated cognitive decline, primarily in perceptual speed. These data show that WMHs are associated with decline in perceptual speed rather than episodic or semantic memory and that cognitive change is more vulnerable to WMH accumulations in deep and periventricular regions.

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.

Role of Orthostatic Hypotension in the Development of Dementia in People With and Without Cardiovascular Disease.

BACKGROUND: Orthostatic hypotension (OH) has been associated with elevated risk of cardiovascular diseases (CVDs) and dementia risk. To better understand the OH-dementia association, we assessed the associations of OH with CVD and subsequent dementia in older adults and considered the temporality of CVD and dementia onset. METHODS: This 15-year population-based cohort study included, at baseline, 2703 dementia-free participants (mean age, 73.7 years) who were divided into a CVD-free cohort (n=1986) and a CVD cohort (n=717). OH was defined as a systolic/diastolic blood pressure decline of ≥20/10 mm Hg after standing up from a supine position. CVDs and dementia were ascertained by physicians or identified from registers. Multistate Cox regressions were applied to assess the associations of OH with CVD and subsequent dementia in the CVD-free and dementia-free cohort. The OH-dementia association in the CVD cohort was examined with Cox regressions. RESULTS: OH was present in 434 (21.9%) individuals in the CVD-free cohort and 180 (25.1%) individuals in the CVD cohort. OH was associated with a hazard ratio of 1.33 (95% CI, 1.12-1.59) for CVD. OH was not significantly associated with incident dementia in the absence of CVD occurring before dementia diagnosis (hazard ratio, 1.22 [95% CI, 0.83-1.81]). In the CVD cohort, individuals with OH had a higher dementia risk than those without OH (hazard ratio, 1.54 [95% CI, 1.06-2.23]). CONCLUSIONS: The association between OH and dementia may partly be explained by the intermediate development of CVD. In addition, in people with CVD, those with OH may have a poorer cognitive prognosis.

Association of ischemic heart disease with long-term risk of cognitive decline and dementia: A cohort study.

INTRODUCTION: The independent and joint effect of ischemic heart disease (IHD) and coexisting atrial fibrillation (AF) and heart failure (HF) on dementia risk is largely unknown. METHODS: This population-based cohort study included 2568 dementia-free participants (age ≥60 years) in SNAC-K, who were regularly examined from 2001-2004 through 2013-2016. Dementia was diagnosed following the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) criteria. Global cognitive function was assessed using a global cognitive composite z-score derived from five cognitive domains. Data were analyzed using Cox, Fine-Gray, and linear mixed-effects models. RESULTS: Overall, IHD at baseline was associated with multivariable-adjusted hazard ratio (HR) of 1.39 (95% confidence interval = 1.06-1.82) for dementia and multivariable-adjusted ß-coefficient of -0.02 (-0.03 to -0.01) for annual changes in global cognitive z-score, independent of AF, HF, and cerebrovascular disease. Coexisting AF or HF did not add further risk to dementia and cognitive decline. DISCUSSION: IHD is independently associated with dementia and cognitive decline in older adults, whereas coexisting AF/HF is not associated with an increased risk. HIGHLIGHTS: Is a history of ischemic heart disease (IHD) associated with a risk for dementia? How do coexisting heart diseases affect this association? IHD was an independent risk factor for dementia in older adults. This association was independent of coexisting heart and cerebrovascular diseases. The coexistence of heart diseases did not confer additional risk for dementia.

The age-dependent association of Life's Simple 7 with transitions across cognitive states after age 60.

BACKGROUND: Life's Simple 7 (LS7) aims to promote ideal cardiovascular health (CVH). Its association with different cognitive states in the older old is unclear. OBJECTIVES: To assess the associations of LS7 with transitions across normal cognition, cognitive impairment, no dementia (CIND), and dementia and evaluate cognitive impairment-free years of life by LS7-defined CVH levels in older adults. METHODS: This cohort study included 2746 participants from the Swedish National Study on Aging and Care in Kungsholmen, regularly examined over 15 years. Total LS7 scores were created and dichotomized into worse and better CVH categories. The associations of LS7 total scores and CVH categories with cognitive states were assessed with multistate models in the whole sample and in younger old (<78 years) and older old adults (≥78 years) separately. Cognitive impairment-free life years by CVH categories were then predicted. RESULTS: A 1-point increment in the LS7 total score was associated with lower dementia risk in younger old adults (hazard ratio: 0.87 [0.78-0.97]) but not in older old adults (1.04 [0.97-1.13]). Better CVH was also associated with a lower risk of transition from normal cognition to CIND (0.76 [0.61-0.95]) and from normal cognition to dementia (0.42 [0.21-0.82]) in younger old adults. In younger old adults, those with better CVH were predicted to have two-to-three more cognitive impairment-free life years than those with worse CVH. CONCLUSION: Maintaining LS7-defined ideal CVH seems relevant in younger old adults but not in older old adults when considering the potential protective effects against cognitive impairment.

A glycan epitope correlates with tau in serum and predicts progression to Alzheimer's disease in combination with APOE4 allele status.

INTRODUCTION: There is an urgent need for novel blood biomarkers for the detection of Alzheimer's disease (AD). We previously showed that levels of the bisecting N-acetylglucosamine glycan epitope was elevated in cerebrospinal fluid in AD. However, its diagnostic value in blood is unknown. METHODS: We analyzed blood levels of bisecting N-acetylglucosamine and total tau in a retrospective cohort of 233 individuals. Progression to AD was compared between the groups using Cox regression. The predictive value of the biomarkers was determined by logistic regression. RESULTS: Bisecting N-acetylglucosamine correlated with tau levels (p < 0.0001). Individuals with an intermediate tau/bisecting N-acetylglucosamine ratio had elevated AD risk (hazard ratio = 2.06, 95% confidence interval [CI]: 1.18-3.6). Moreover, a combined model including tau/bisecting N-acetylglucosamine ratio, apolipoprotein E (APOE) ε4 status, and Mini-Mental State Examination score predicted future AD (area under the curve = 0.81, 95% CI: 0.68-0.93). DISCUSSION: Bisecting N-acetylglucosamine in combination with tau is a valuable blood biomarker for predicting AD.

Odor identification errors reveal cognitive aspects of age-associated smell loss.

Human olfaction can be extraordinarily sensitive, and its most common assessment method is odor identification (OID), where everyday odors are matched to word labels in a multiple-choice format. However, many older persons are unable to identify familiar odors, a deficit that is associated with the risk of future dementia and mortality. The underlying processes subserving OID in older adults are poorly understood. Here, we analyzed error patterns in OID to test whether errors could be explained by perceptual and/or semantic similarities among the response alternatives. We investigated the OID response patterns in a large, population-based sample of older adults in Sweden (n = 2479; age 60-100 years). Olfaction was assessed by a 'Sniffin ́ TOM OID test with 16 odors; each trial involved matching a target odor to a correct label among three distractors. We analyzed the pattern of misidentifications, and the results showed that some distractors were more frequently selected than others, suggesting cognitive or perceptual factors may be present. Relatedly, we conducted a large online survey of older adults (n = 959, age 60-90 years) who were asked to imagine and rate the perceptual similarity of the target odors and the three corresponding distractors (e.g. "How similar are these smells: apple and mint?"). We then used data from the Swedish web corpus and the Word2Vec neural network algorithm to quantify the semantic association strength between the labels of each target odor and its three distractors. These data sources were used to predict odor identification errors. We found that the error patterns were partly explained by both the semantic similarity between target-distractor pairs, and the imagined perceptual similarity of the target-distractor pair. Both factors had, however, a diminished prediction in older ages, as responses became gradually less systematic. In sum, our results suggest that OID tests not only reflect olfactory perception, but also likely involve the mental processing of odor-semantic associations. This may be the reason why these tests are useful in predicting dementia onset. Our insights into olfactory-language interactions could be harnessed to develop new olfactory tests that are tailored for specific clinical purposes.

Association between personality traits, leisure activities, and cognitive levels and decline across 12 years in older adults.

The engagement in cognitively stimulating activities has been found to be associated with slower rates of cognitive decline in old age. In which type of activities people engage in may depend on their personality traits, which thus might have an impact on later cognitive fitness. To study these potential links, we examined the associations between Neuroticism, Extraversion, and Openness; different types of leisure activities (e.g., social, mental, physical); and cognitive ability levels and decline in older adults. Analyses were based on a sample of young-old (60-72 years old; n = 1,609) and old-old (78 years or older; n = 1,085) adults from the Swedish National Study on Aging and Care in Kungsholmen, who participated in up to five repeated measurements of cognitive abilities spanning 12 years. We used latent growth curve models to estimate cognitive levels and decline, as well as the correlations with initial personality trait levels and leisure activity engagement. In both groups, lower Neuroticism, higher Extraversion, and higher Openness levels were moderately associated with stronger engagement in all types of activities. Lower Neuroticism, higher Extraversion, and a more activity lifestyle were weakly to moderately associated with slower cognitive decline in the old-old age group. There, personality traits and activities explained 9.3% of the variance in cognitive decline after controlling for age, sex, education, and chronic diseases (which explained 9.0%). Taken together, this study provides further evidence for the connection between personality traits, activity engagement, and later cognitive decline in old age. (PsycInfo Database Record (c) 2023 APA, all rights reserved).