Domain-specific Cognitive Function Research Articles

The association between adherence to the EAT-Lancet diet and cognitive ageing.

The EAT-Lancet commission has proposed a dietary pattern that is both sustainable and healthy. However, the impact of this diet on cognition in older adults remains unexplored. Therefore, we examined the association between adherence to the EAT-Lancet diet and cognitive ageing. We used data from a previous intervention study involving cognitively healthy community-dwelling adults aged ≥65years. Adherence to the EAT-Lancet diet was calculated using a recently published index and a 190-item food frequency questionnaire. Global and domain-specific cognitive functioning were assessed at baseline and after 2 years using a neuropsychological test battery. Multivariate-adjusted linear regression was conducted to examine associations between EAT-Lancet diet adherence and cognitive functioning (n = 630) and 2-year change (n = 302). Greater adherence to the EAT-Lancet diet was associated with better global cognitive functioning (β per SD = 3.7 points [95% CI]: 0.04 [0.00, 0.08]) and slower rate of decline (β per SD [95% CI]: 0.05 [0.02, 0.08]). With respect to domain-specific functioning, beneficial associations were observed cross-sectionally for executive functioning (P < 0.01), and longitudinally for change in executive functioning (P < 0.01) and attention and working memory (P < 0.01). The degree of adherence to the EAT-Lancet was not associated with (changes in) information processing speed or episodic memory. We demonstrated that greater adherence to the EAT-Lancet diet is associated with better global cognitive functioning and slower cognitive decline among cognitively healthy older adults. Further research is needed to confirm these findings and assess the potential benefits of the EAT-Lancet diet for the ageing population in a broader context.

Neighborhood disadvantage is associated with working memory and hippocampal volumes among older adults

ABSTRACT It is not well understood how neighborhood disadvantage is associated with specific domains of cognitive function and underlying brain health within older adults. Thus, the objective was to examine associations between neighborhood disadvantage, brain health, and cognitive performance, and examine whether associations were more pronounced among women. The study included 136 older adults who underwent cognitive testing and MRI. Neighborhood disadvantage was characterized using the Area Deprivation Index (ADI). Descriptive statistics, bivariate correlations, and multiple regressions were run. Multiple regressions, adjusted for age, sex, education, and depression, showed that higher ADI state rankings (greater disadvantage) were associated with poorer working memory performance (p < .01) and lower hippocampal volumes (p < .01), but not total, frontal, and white matter lesion volumes, nor visual and verbal memory performance. There were no significant sex interactions. Findings suggest that greater neighborhood disadvantage may play a role in working memory and underlying brain structure.

Strategic white matter hyperintensity locations associated with post-stroke cognitive impairment: a multicenter study in 1568 stroke patients.

Post-stroke cognitive impairment (PSCI) occurs in up to 50% of stroke survivors. Presence of pre-existing vascular brain injury, in particular the extent of white matter hyperintensities (WMH), is associated with worse cognitive outcome after stroke, but the role of WMH location in this association is unclear. We determined if WMH in strategic white matter tracts explain cognitive performance after stroke. Individual patient data from 9 ischemic stroke cohorts with MRI were harmonized through the Meta VCI Map consortium. The association between WMH volumes in strategic tracts and domain-specific cognitive functioning (attention and executive functioning, information processing speed, language and verbal memory) was assessed using linear mixed models and lasso regression. We used a hypothesis-driven design, primarily addressing four white matter tracts known to be strategic in memory clinic patients: the left and right anterior thalamic radiation, forceps major and left inferior fronto-occipital fasciculus. The total study sample consisted of 1568 patients (39.9% female, mean age: 67.3 years). Total WMH volume was strongly related to cognitive performance on all four cognitive domains. WMH volume in the left anterior thalamic radiation was significantly associated with cognitive performance on attention and executive functioning and information processing speed, and WMH volume in the forceps major with information processing speed. The multivariable lasso regression showed that these associations were independent of age, sex, education, and total infarct volume and had larger coefficients than total WMH volume. These results show tract-specific relations between WMH volume and cognitive performance after ischemic stroke, independent of total WMH volume. This implies that the concept of strategic lesions in PSCI extends beyond acute infarcts and also involves pre-existing WMH. The Meta VCI Map consortium is dedicated to data sharing, following our guidelines.

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.

Prevalence of obstructive sleep apnoea risk and its association with anthropometric indices of cardiometabolic risks and cognition in young and middle-aged adults

Objectives: Obstructive sleep apnoea (OSA), an often underdiagnosed and undertreated sleep-related breathing disorder, is associated with an increased risk of cardiovascular morbidity and mortality. Hence, this study aimed to assess the prevalence of OSA risk and its association with anthropometric indices (AI) of cardiometabolic risks, domain-specific cognitive functions and quality of sleep in apparently healthy young and middle-aged adults. Materials and Methods: One hundred and eighty-nine apparently healthy individuals (123 males and 66 females) aged 19–45 years were included in this cross-sectional study. The participant’s current risk of OSA was assessed using the STOP-Bang questionnaire, and AI indicative of cardiometabolic risk (body mass index, waist-hip ratio [W/H ratio], waist-height ratio [WHtR], conicity index and a body shape index) was assessed using standard techniques. Domain-specific cognitive tests were performed to assess the cognitive status of the individual. Quality of sleep was assessed using the Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale. The correlation between the OSA risk score and the study parameters was assessed using the Pearson or Spearman correlation coefficient test. Results: The prevalence of high current risk of moderate to severe OSA was found to be 12.7%. Significant positive correlations were observed between OSA risk score and W/H, WHtR and sleep quality scores. While a significant positive correlation was observed between OSA risk score and executive functioning, significant negative correlations were observed with the other cognitive tests (short-term memory, verbal fluency, visuospatial memory and sustained attention and response speed). Conclusion: A high risk of moderate to severe OSA is associated with obesity, cognitive decline and poor sleep quality in apparently healthy young and middle-aged adults.

Social isolation and cognitive function in patients with schizophrenia: A two years follow-up study

Cognitive impairment is a core characteristic of schizophrenia. Social isolation has been linked to impaired cognitive function among the general population. In this longitudinal study, we examined the association between social isolation and cognitive function among inpatients with schizophrenia. Two waves of data (2019 and 2021) were collected from chronic psychiatric wards. A total of 166 inpatients completed all measurements at baseline and follow-up. Social isolation was measured by incorporating the frequency of social contact and participation, while cognitive functions were assessed by the Taiwan version of the Montreal Cognitive Assessment (MoCA-T). We used multiple linear regression to evaluate the link between baseline social isolation and cognitive function. For the total sample, social isolation was significantly related to poor language abilities (β = −0.17, p = 0.013) and delayed recall (β = −0.15, p = 0.023). Sex-stratified analysis showed that social isolation was significantly related to poor global cognitive function (β = −0.14, p = 0.021) and domain-specific cognitive functions including language abilities (β = −0.26, p = 0.003) and delayed recall (β = −0.19, p = 0.045) in male inpatients. No significant association was found between social isolation and global cognitive function or any cognitive domain (all ps > 0.05) for females. All associations were independent of loneliness and other covariates. These findings suggested that social isolation could predict poor subsequent cognitive function in inpatients with schizophrenia, especially in males. Interventions aimed at enhancing social connections could potentially improve cognitive function in this population.

Post-stroke Cognition is Associated with Stroke Survivor Quality of Life and Caregiver Outcomes: A Systematic Review and Meta-analysis.

Disability arising from post-stroke cognitive impairment is a likely contributor to the poor quality of life (QoL) stroke survivors and their carers frequently experience, but this has not been summarily quantified. A systematic literature review and meta-analysis was completed examining the association between general and domain-specific post-stroke cognitive functioning and adult stroke survivor QoL, caregiver QoL, and caregiver burden. Five databases were systematically searched, and eligibility for inclusion, data extraction, and study quality were evaluated by two reviewers using a standardised protocol. Effects sizes (r) were estimated using a random effects model. Thirty-eight studies were identified, generating a sample of 7365 stroke survivors (median age 63.02years, range 25-93) followed for 3 to 132months post-stroke. Overall cognition (all domains combined) demonstrated a significant small to medium association with QoL, r = 0.23 (95% CI 0.18-0.28), p < 0.001. The cognitive domains of speed, attention, visuospatial, memory, and executive skills, but not language, also demonstrated a significant relationship with QoL. Regarding caregiver outcomes, 15 studies were identified resulting in a sample of 2421 caregivers (median age 58.12years, range 18-82) followed for 3 to 84months post-stroke. Stroke survivor overall cognitive ability again demonstrated a significant small to medium association with caregiver outcomes (QoL and burden combined), r = 0.17 (95% CI 0.10-0.24), p < 0.001. In conclusion, lower post-stroke cognitive performance is associated with significant reductions in stroke survivor QoL and poorer caregiver outcomes. Cognitive assessment is recommended early to identify those at risk and implement timely interventions to support both stroke survivors and their caregivers.

Neuropsychological correlates of early grief in bereaved older adults.

Prolonged grief disorder (PGD) is associated with impairments in cognitive functioning, but the neuropsychological correlates of early grief in older adults are poorly understood. This preliminary study cross-sectionally examined neuropsychological functioning in bereaved adults with high and low grief symptoms and a non-bereaved comparison sample and further explored the relationship between multidomain cognitive measures and grief severity. A total of ninety-three nondemented older adults (high grief: n = 44; low grief: n = 49) within 12 months post-bereavement and non-bereaved comparison participants (n = 43) completed neuropsychological battery including global and multiple domain-specific cognitive functioning. Linear regression models were used to analyze differences in multidomain cognitive measures between the groups and specifically examine the associations between cognitive performance and grief severity in the bereaved, after covariate adjustment, including depressive symptoms. Bereaved older adults with higher grief symptoms performed worse than those with lower symptoms and non-bereaved participants on executive functioning and attention and processing speed measures. In the bereaved, poorer executive functioning, attention and processing speed correlated with higher grief severity. Attention/processing speed-grief severity correlation was seen in those with time since loss ≤ 6 months, but not > 6 months. Intense early grief is characterised by poorer executive functioning, attention, and processing speed, resembling findings in PGD. The putative role of poorer cognitive functioning during early grief on the transition to integrated grief or the development of PGD remains to be elucidated.

Effects of neighborhood built environment on cognitive function in older adults: a systematic review

BackgroundIn the background of an aging population, the risk of cognitive impairment in the older population is prominent. Exposure to complex neighborhood built environments may be beneficial to the cognitive health of older adults, and the purpose of this study was to systematically review the scientific evidence on the effects of neighborhood built environments on cognitive function in older adults.MethodsKeywords and references were searched in Web of Science, Pubmed, PsycINFO, and MEDLINE. Studies examining the relationship between the built environment and cognitive function in older adults were included. The neighborhood built environment as an independent variable was classified according to seven aspects: density, design, diversity, destination accessibility, public transportation distance, blue/green space, and built environment quality. The cognitive function as the dependent variable was classified according to overall cognitive function, domain-specific cognitive function, and incidence of dementia. The quality of the included literature was assessed using the National Institutes of Health's Observational Cohort and Cross-Sectional Study Quality Assessment Tool.ResultsA total of 56 studies were included that met the inclusion criteria, including 31 cross-sectional studies, 23 longitudinal studies, 1 cross-sectional study design combined with a case-control design, and 1 longitudinal study design combined with a case-control design. Most of the studies reviewed indicate that the built environment factors that were positively associated with cognitive function in older adults were population density, street connectivity, walkability, number of public transportation stops around the residence, land use mix, neighborhood resources, green space, and quality of the neighborhood built environment. Built environment factors that were negatively associated with cognitive function in older adults were street integration, distance from residence to main road. The relationship between residential density, destination accessibility, and blue space with cognitive function in older adults needs to be further explored.ConclusionPreliminary evidence suggests an association between the neighborhood built environment and cognitive function in older adults. The causal relationship between the built environment and cognitive function can be further explored in the future using standardized and combined subjective and objective assessment methods, and longitudinal or quasi-experimental study designs. For public health interventions on the cognitive health of older adults, it is recommended that relevant authorities include the neighborhood built environment in their intervention programs.

Polygenic burden and its association with baseline cognitive function and postoperative cognitive outcome in temporal lobe epilepsy

ObjectiveDemographic and disease factors are associated with cognitive deficits and postoperative cognitive declines in adults with pharmacoresistant temporal lobe epilepsy (TLE), but the role of genetic factors in cognition in TLE is not well understood. Polygenic scores (PGS) for neurological and neuropsychiatric disorders and IQ have been associated with cognition in patient and healthy populations. In this exploratory study, we examined the relationship between PGS for Alzheimer’s disease (AD), depression, and IQ and cognitive outcomes in adults with TLE. Methods202 adults with pharmacoresistant TLE had genotyping and completed neuropsychological evaluations as part of a presurgical work-up. A subset (n = 116) underwent temporal lobe resection and returned for postoperative cognitive testing. Logistic regression was used to determine if PGS for AD, depression, and IQ predicted baseline domain-specific cognitive function and cognitive phenotypes as well as postoperative language and memory decline. ResultsNo significant findings survived correction for multiple comparisons. Prior to correction, higher PGS for AD and depression (i.e., increased genetic risk for the disorder), but lower PGS for IQ (i.e., decreased genetic likelihood of high IQ) appeared possibly associated with baseline cognitive impairment in TLE. In comparison, higher PGS for AD and IQ appeared as possible risk factors for cognitive decline following temporal lobectomy, while the possible relationship between PGS for depression and post-operative cognitive outcome was mixed. SignificanceWe did not observe any relationships of large effect between PGS and cognitive function or postsurgical outcome; however, results highlight several promising trends in the data that warrant future investigation in larger samples better powered to detect small genetic effects.

Trajectories of cognitive decline in different domains prior to AD onset in persons with mild cognitive impairment

ObjectivesTo explore the trajectories and the change-points of global and five domain-specific cognitive functions before the onset of Alzheimer's disease (AD). MethodsData was retrieved from the Alzheimer's Disease Neuroimaging Initiative with follow-up from 2005 to 2022. Participants with mild cognitive impairment (MCI) at baseline and those who progressed to AD during follow-up were included. The time of AD onset was defined as the visit time when participant was first diagnosed as AD during follow-up. Global and five domain-specific cognitive functions (immediate memory, visuospatial ability, language, processing speed and executive function) were assessed by Mini-Mental State Examination, Immediate recalling trials of Rey Auditory Verbal Learning Test, Clock Drawing Test, Animal Fluency Test, Part A and B of Trail Making Test, respectively. Their trajectories and change-points before AD onset were explored by generalized additive mixed models and piecewise linear regression models, respectively. Results349 participants were diagnosed as MCI at baseline and converted to AD during follow-up, who were included in this study. They had been visited on an average of 4.6 times (SD = 2.1, range = 2.0–13.0), with a total of 1593 visits. Their mean baseline age and AD onset age were 74.4 (SD = 6.4, range = 60.0–88.4) and 77.0 (SD = 6.8, range = 60.5–94.7) years, respectively. Baseline age and educational year were significantly associated with global cognitive, immediate memory, language and executive function. Men presented better global cognitive function (β = 0.54, p < 0.05) but poorer immediate memory (β = −1.72, p < 0.05) than women. Immediate memory and visuospatial ability showed the earliest change-points at 4 years before the onset of AD (Note as T-4years), followed by language (T-3.5years), executive function (T-2.5 years), processing speed (T-2.0 years), and finally the global cognitive function (T-1.5years). ConclusionsThe trajectories of the six neuropsychological scores were non-linear and showed deterioration in functions over time. Immediate memory and visuospatial ability showed the earliest change-points prior to AD onset.

Brain-IT: Targeting the brain using information technology for secondary prevention of mild neurocognitive disorder

Introduction A collaborative international guideline recommends physical exercise (PE) for the secondary prevention of mild neurocognitive disorder (mNCD; Veronese et al., 2023). PE is proposed to promote brain plasticity, maintain or increase cognitive reserve, and alleviate the pathological state in individuals with mNCD, which is characterized by an abnormal accumulation of proteins, excessive oxidative stress, metabolic disorder, and neuroinflammation within the brain (Lu et al., 2023). Individuals with mNCD often also have disrupted self-regulatory capacity to flexibly adapt to daily life challenges. This capacity is supported by the central autonomic network (CAN), which can be viewed as an integrated component of an internal regulatory system in which the brain controls visceromotor, neuroendocrine, and behavioral responses that are critical for goal-directed behavior, adaptability, and health (Thayer, 2009). To maximize the effectiveness of secondary prevention of mNCD, interventions should be designed to also target this network specifically. This could be achieved by combining motor-cognitive training with resonance breathing guided by heart rate variability biofeedback (HRV-BF). HRV-BF training aims to increase cardiac autonomic control, enhance homeostatic regulation, and regulate emotional state. It is effective in improving cardiac autonomic control, cognitive functioning (in particular executive functions), and emotional regulation (i.e., by decreasing symptoms of depression, anxiety, and stress) across different age groups and clinical populations (Laborde et al., 2022; Lehrer et al., 2020). Evidence also supports a causal role of cardiac autonomic control in modulating plasma Alzheimer’s disease-related biomarkers (Min et al., 2023). Although HRV-BF has been suggested as a complementary treatment (Lehrer et al., 2020), its combination with motor-cognitive training remains to be investigated. Methods We systematically designed, developed, and evaluated a novel training concept (called ‘Brain-IT’) specifically for older adults with mNCD. It addresses the mechanism of action described above. The projects’ methodology (Manser &amp; de Bruin, 2021) followed the guidelines of the Medical Research Council for the development and evaluation of complex interventions as well as the Multidisciplinary Iterative Design of Exergames (MIDE) - Framework. The Brain-IT project was structured in three phases. In phase 1, we systematically combined a comprehensive literature synthesis (Manser &amp; de Bruin, 2021) with qualitative research including primary end users (older adults with mNCD), secondary end users (physiotherapists, occupational therapists, healthcare professionals), exergaming researchers, as well as experts from the exergaming industry (Manser et al., 2023) to specify a set of design requirements for the Brain-IT training concept. In phase 2, possible concepts were co-designed and elaborated based on the set of design requirements defined in phase 1. The first prototype of the resulting Brain-IT training concept (Manser &amp; de Bruin, 2021) then entered the iterative cycle of feasibility, usability, safety, and acceptance testing and integrating study results for further development based on co-design until an "acceptable" solution was achieved. In this regard, we conducted a pilot randomized controlled study (RCT) including 18 individuals with mNCD. (Manser et al., 2023) Finally, in phase 3, the effectiveness of the addition of the Brain-IT training to usual care to improve global cognitive functioning is investigated in a RCT including 41 individuals with mNCD (study protocol: Manser et al., 2023). As secondary objectives, the effects of the Brain-IT training on: (1) domain-specific cognitive functioning, (2) spatiotemporal parameters of gait, (3) instrumental activities of daily living and (4) psychosocial factors (i.e. quality of life, and levels of depression, anxiety, and stress), and (5) cardiac vagal modulation are explored. Additionally, brain structure and function is evaluated by magnetic resonance imaging to explore underlying neural changes of the training in relation to adaptations in cognitive performance. Results Ten secondary end users, exergaming researchers, and experts from the exergaming industry (80% females) and eight older adults with mNCD (38% females) contributed to the qualitative research (Manser et al., 2023) which allowed us to successfully integrate all the acquired knowledge of phase 1 to determine a set of design requirements (Manser &amp; de Bruin, 2021). This set of design requirements built the basis for phase 2, where we developed a first prototype of the Brain-IT training concept. Our reflections on the design considerations and our proposed solutions are summarized in (Manser &amp; de Bruin, 2021; Manser et al., 2023). The Brain-IT training concept represents a guideline for applying a combination of exergame-based motor-cognitive training and HRV-BF training by standardizing the training characteristics as well as the structure and content of training and can be implemented with different hardware and software solutions. For an overview, the Brain-IT training consists of a personalized and individually adapted multi-domain exergame-based simultaneous motor–cognitive training with incorporated cognitive tasks combined with HRV-BF training. It is adopted with a deficit-oriented focus on the neurocognitive domains of (1) learning and memory, (2) executive function, (3) complex attention, and (4) visuospatial skills. Each participant is instructed to train ≥ 5x/week for ≥ 24 min per session resulting in a weekly training volume of ≥120 min. All training sessions are planned to take place at participants’ homes. In this project, we used technology of Dividat AG, Polar, and Kubios Oy to implement our training concept. In the pilot RCT we showed that Brain-IT training is feasible (mean adherence and compliance rates of 85.0 and 84.1%, respectively) and usable (mean system usability scale = 71.7 ± 15.4). In addition, high levels of exergame enjoyment, an increase in exergame enjoyment, and internalization of training motivation with large effect sizes (p = 0.03, r = 0.75 and p = 0.03, r = 0.74, respectively), as well as acceptable perceived usefulness were observed. Phase 3 is ongoing. To date, 41 participants were included into the study, of which two withdrew consent before pre-measurements, two dropped-out during intervention (one in each group), and 29 (72.6 ± 9.3 years; 24.1% females) successfully completed the study. Preliminary data suggest significant effects with large effects sizes in favor of the intervention group for global cognitive functioning (F(1, 29) = 4.692, p = 0.039, partial η2 = 0.153) as well as immediate (F(1, 29) = 6.501, p = 0.018, partial η2 = 0.213) and delayed (F(1, 29) = 5.227, p = 0.031, partial η2 = 0.179) verbal recall. The remaining (underpowered) statistical analyses revealed no significant effects, but favorable changes in descriptive statistics with small to moderate effects in favor of the intervention group, especially with regards to quality of life. Discussion/Conclusion The development of novel (exergame-based) training concepts is greatly facilitated when it is based on a theoretical framework. Applying the MIDE-framework resulted in a structured, iterative, and evidence-based approach that led to the identification of multiple key requirements for the exergame design as well as the training components that otherwise may have been overlooked or neglected. This resulted in a user-centered, personalized, and highly innovative training concept that is feasible, usable, and highly accepted by individuals with mNCD. Preliminary data regarding the effectiveness of the intervention is promising, suggesting that the training significantly improved global cognitive functioning, verbal immediate, and delayed recall with large effect sizes, and tends to be beneficial in improving quality of life. To be able to conclude about the effectiveness of the Brain-IT training concept, a full-scale confirmatory randomized controlled superiority trial is warranted.

A Cross-Sectional Study of Cognitive Function, Illness Perceptions, and Immunosuppression Medication Adherence After Heart Transplantation.

There are few studies that examine relationships between cognitive function, illness perceptions, and medication adherence after heart transplantation, limiting the development of effective adherence-promoting interventions. The purpose of this study was to describe relationships between cognitive function, illness perceptions, and medication adherence among heart transplant recipients. A cross-sectional, observational design was used. Measures included the telephone-Montreal Cognitive Assessment (t-MoCA©), Patient Health Questionnaire-9, Brief Test of Adult Cognition by Telephone, Basel Assessment of Adherence to Immunosuppressive Medications Scale, and the Brief Illness Perceptions Questionnaire. Descriptive statistics, point-biserial correlations, Pearson's correlations, and logistic regression were used to describe relationships. Of the 35 participants (mean age: 61 years [SD: 10.3], 71.4% male, 71.4% white), 31.4% (n = 11) were classified as nonadherent to their immunosuppression medications. Higher immediate word recall, indicating better episodic memory (memory for autobiographical and recent events), and higher illness coherence scores were associated with not missing doses of medication. Higher t-MoCA© total scores, indicating normal cognitive function, and lower depression scores were associated with taking medications on time. More than 22% (n = 8) of participants scored less than 19 on the t-MoCA©, an indication of mild cognitive impairment. Cognitive impairment may be more common among heart transplant recipients than what is currently recognized, and specific domains of cognitive function were related to medication adherence after transplantation in this study. Future studies should include longitudinal evaluations of cognitive function, depression, and medication adherence. Consideration of these relationships is needed when designing adherence-promoting interventions for this population.

The Association between Education and Cognitive Performance Varies at Different Levels of Cognitive Performance: A Quantile Regression Approach

Introduction: Educational differences in cognitive performance among older adults are well documented. Studies that explore this association typically estimate a single average effect of education on cognitive performance. We argue that the processes that contribute to the association between education and cognitive performance are unlikely to have equal effects at all levels of cognitive performance. In this study, we employ an analytical approach that enables us to go beyond averages to examine the association between education and five measures of global and domain-specific cognitive performance across the outcome distributions. Methods: This cross-sectional study included 1,780 older adults aged 58–68 years from the Longitudinal Aging Study Amsterdam. Conditional quantile regression was used to examine variation across the outcome distribution. Cognitive outcomes included Mini-Mental State Examination (MMSE) score, crystallized intelligence, information processing speed, episodic memory, and a composite score of global cognitive performance. Results: The results showed that the associations between education and different cognitive measures varied across the outcome distributions. Specifically, we found that education had a stronger association with crystallized intelligence, MMSE, and a composite cognitive performance measure in the lower tail of performance distributions. The associations between education and information processing speed and episodic memory were uniform across the outcome distributions. Conclusion: Larger associations between education and some domains of cognitive performance in the lower tail of the performance distributions imply that inequalities are primarily generated among individuals with lower performance rather than among average and high performers. Additionally, the varying associations across some of the outcome distributions indicate that estimating a single average effect through standard regression methods may overlook variations in cognitive performance between educational groups. Future studies should consider heterogeneity across the outcome distribution.

Effect of cocoa extract supplementation on cognitive function: results from the clinic subcohort of the COSMOS trial

BackgroundSome prior randomized clinical trials (RCTs) that tested the effects of cocoa extract (CE), a source of flavanols, on late-life cognition have yielded promising findings. A long-term RCT using in-person neuropsychological tests covering multiple cognitive domains may clarify the cognitive effects of CE. ObjectivesTo test whether daily supplementation with CE, compared with placebo, produces better cognitive change over 2 y. MethodsThe COcoa Supplement and Multivitamin Outcomes Study (COSMOS) is a 2 × 2 factorial RCT of CE [500 mg flavanols/d, including 80 mg (–)-epicatechin] and/or a daily multivitamin-mineral supplement for cardiovascular disease and cancer prevention among 21,442 United States adults aged ≥60 y. There were 573 participants in the clinic subcohort of COSMOS (that is, COSMOS-Clinic) who completed all cognitive tests at baseline; of these, 492 completed 2-y follow-up assessments. The primary outcome was global cognition (averaging z-scores across 11 tests). Secondary outcomes were episodic memory and executive function/attention. Repeated measures models were used to compare randomized groups. ResultsParticipants' mean age (standard deviation) was 69.6 (5.3); 49.2% were females. Daily supplementation with CE, compared with placebo, had no significant effect on 2-y change in global cognition {mean difference [95% confidence interval (CI)]: −0.01 (−0.08, 0.05) standard deviation units (SU)}. CE, compared with placebo, had no significant effects on 2-y change in episodic memory [mean difference (95% CI): −0.01 (−0.13, 0.10) SU] or executive function/attention [mean difference (95% CI): 0.003 (−0.07, 0.08) SU]. Subgroup analyses uncorrected for multiple-testing suggested cognitive benefits of CE supplementation, compared with placebo among those with poorer baseline diet quality. ConclusionsAmong 573 older adults who underwent repeat in-person, detailed neuropsychological assessments over 2 y, daily CE supplementation, compared with placebo, showed no overall benefits for global or domain-specific cognitive function. Possible cognitive benefits of CE among those with poorer diet quality warrant further study. Trial registrationThis trial was registered at clinicaltrials.gov with identifier – NCT02422745.

Relationship between hippocampal subfield volumes and cognitive decline in healthy subjects.

We examined the relationship between hippocampal subfield volumes and cognitive decline over a 4-year period in a healthy older adult population with the goal of identifying subjects at risk of progressive cognitive impairment which could potentially guide therapeutic interventions and monitoring. 482 subjects (68.1 years +/- 7.4; 52.9% female) from the Irish Longitudinal Study on Ageing underwent magnetic resonance brain imaging and a series of cognitive tests. Using K-means longitudinal clustering, subjects were first grouped into three separate global and domain-specific cognitive function trajectories; High-Stable, Mid-Stable and Low-Declining. Linear mixed effects models were then used to establish associations between hippocampal subfield volumes and cognitive groups. Decline in multiple hippocampal subfields was associated with global cognitive decline, specifically the presubiculum (estimate -0.20; 95% confidence interval (CI) -0.78 - -0.02; p = 0.03), subiculum (-0.44; -0.82 - -0.06; p = 0.02), CA1 (-0.34; -0.78 - -0.02; p = 0.04), CA4 (-0.55; -0.93 - -0.17; p = 0.005), molecular layer (-0.49; -0.87 - -0.11; p = 0.01), dentate gyrus (-0.57; -0.94 - -0.19; p = 0.003), hippocampal tail (-0.53; -0.91 - -0.15; p = 0.006) and HATA (-0.41; -0.79 - -0.03; p = 0.04), with smaller volumes for the Low-Declining cognition group compared to the High-Stable cognition group. In contrast to global cognitive decline, when specifically assessing the memory domain, cornu ammonis 1 subfield was not found to be associated with low declining cognition (-0.14; -0.37 - 0.10; p = 0.26). Previously published data shows that atrophy of specific hippocampal subfields is associated with cognitive decline but our study confirms the same effect in subjects asymptomatic at time of enrolment. This strengthens the predictive value of hippocampal subfield atrophy in risk of cognitive decline and may provide a biomarker for monitoring treatment efficacy.

Multiple sensory impairments in relation to cognitive function: two nationwide cross‐sectional studies

AbstractBackgroundSensory impairments (SIs, including visual, hearing, olfactory, and taste impairments) have been individually associated with age‐related cognitive function. Little is known regarding their combined associations with cognitive function.MethodWe included 2,931 participants (mean age of 69.1 years) from the National Health and Nutrition Examination Survey (NHANES, 2011‐2014) and 10,785 participants (mean age of 70.2 years) from the National Health Interview Survey (NHIS, 2021). Status of visual, hearing, olfactory, and taste functions were self‐reported in structured questionnaires. In NHANES, cognitive function was objectively measured by a battery of tests, including memory, verbal fluency, and processing speed. NHIS participants answered a single question about their subjective cognitive complaints (SCC). We used regression models to assess the relation of total number of and the specific sensory impairments to z‐scores of cognitive domains (linear regression) in NHANES and with SCC (logistic regression) in NHIS.ResultA larger number of SI was related to poorer domain‐specific cognitive function (all P‐trend &lt;0.05), including memory (beta each additional SI = ‐0.12, 95% confidence interval: ‐0.17 to ‐0.08), verbal fluency (‐0.05, ‐0.10 to ‐0.01), and processing speed (‐0.13, ‐0.16 to ‐0.09). In NHIS, each additional SI was related to 96% higher odds of SCC. We also observed independent associations of multiple sensory impairments (except olfactory impairment) with specific domains of cognitive function. In addition, each specific SI showed significant relations to higher odds of SCC (the odds ratios ranged from 1.30 to 1.78).ConclusionA larger number of SI was related to worse cognitive function and higher odds of subjective cognitive complaints.

Impact of White Matter Hyperintensities on domain‐specific cognition in Southeast Asians

AbstractBackgroundDementia affects 55 million people worldwide, with 60% of the burden in Asia. White Matter Hyperintensities (WMH) is a key marker of small vessel disease, with high prevalence in Asian populations with prodromal and clinical dementia. WMH is described as: Deep White Matter Hyperintensities (DWMH), Periventricular Hyperintensities (PVH) or Fazekas‐Total (DWMH and PVH).However, association between WMH topography and performance in specific cognitive domains remains unexplored. Thus, this study aims to characterise the impact of Fazekas‐Total, DWMH and PVH on different cognitive domains.Method304 participants (mean age 60.6, mean education years 14.2, mean Montreal Cognitive Assessment 25.99, 43.8% males) from Biomarkers and Cognition Study, Singapore (Dementia Research Centre (Singapore)) met the inclusion criteria.Eight domains of cognition were tested: global cognition, learning and memory, language, executive function, complex‐attention, perceptual‐motor, social‐cognition, and processing speed.Normality tests, correlation analysis and stepwise regression (with Benjamini and Hochberg False Discovery Rate correction) were performed to understand association between Fazekas‐Total, DWMH, PVH on domains of cognition tested, accounting for age, education, and gender.Two approaches were used for data analysis: (1) by grouping participants as Mild Cognitive Impairment (MCI), Subjective Cognitive Decline (SCD) and Cognitively Normal (CN) as per the National Institute on Aging‐Alzheimer’s Association (NIA‐AA) criteria and (2) by grouping participants’ WMH as confluent (DWMH ≥2 and PVH ≥3) and non‐confluent.ResultHigher Fazekas‐Total was associated with slower processing speed (p = 0.0255, R = ‐0.039) in prodromal participants (MCI and SCD). Higher PVH was associated with slower processing speed in MCI (p = 0.017, R = ‐0.32) and CN (p = 0.017, R = ‐0.663) participants. Higher PVH was significantly associated with poorer learning and memory (p = 0.045, R = ‐0.043) in SCD participants. Higher DWMH was significantly associated with poorer learning and memory (p = 0.017, R = ‐0.765) in CN participants.ConclusionThese results demonstrate differential association between PVH, DWMH and cognitive domains, thus the location of WMH determines the affected cognitive domains. Therefore, it is worthwhile to assess PVH and DWMH in clinical cognitive outcomes separately and to understand the upstream pathobiology of DWMH and PVH.Furthermore, higher Fazekas‐Total was strongly associated with slower processing speed in prodromal participants and could be a marker of cognitive decline.

Low-Grade systemic inflammation is associated with domain-specific cognitive performance and cognitive decline in older adults: Data from the TUDA study

Studies examining the relationships between chronic inflammation, cognitive function and cognitive decline in older adults have yielded conflicting results. In a large cohort of older adults free from established dementia (n = 3270; 73.1 ± 7.9 years; 68.4% female), we evaluated the cross-sectional and longitudinal relationships between serum cytokines (IL-6, IL-10, TNF-α) and both global and domain-specific cognitive performance (Repeatable Battery for Assessment of Neuropsychological Status [RBANS]). Higher IL-6 (OR: 1.33; 1.06, 1.66, p = 0.01), TNF-α (OR: 1.35; 1.09, 1.67, p = 0.01) and IL-6:IL-10 Ratio (OR: 1.43; 1.17, 1.74, p = 0.001) were cross-sectionally associated with impaired global RBANS performance. For specific cognitive domains, greatest effect sizes were observed between higher TNF-α levels and poorer visual-spatial and attention performance. In a subset of participants (n = 725; 69.8 ± 5.5 years; 67.0% female) with repeat assessment performed at a median of 5.4 years, only higher baseline IL-6:IL-10 ratio was associated with impaired incident overall, immediate memory and visual-spatial performance. Associations were stronger in females, but not modified by age or APOE genotype.

The Relationship between Physical Fitness and Cognitive Functions in Older People: A Systematic Review

The ageing process is associated with vulnerabilities, such as cognitive decline. Physical activity and exercise are key for preserving cognitive health in older age. This systematic review aims to analyse the effects of physical fitness programs on healthy older adults’ cognitive functions. An electronic search was performed in the PubMed, Web of Science, and Scopus databases. It included observational and experimental studies published between February 2017 and March 2023. Of the 1922 studies identified, 38 met the inclusion criteria. The findings show the positive effects of physical training on cognitive function in older adults. The most examined cognitive domains were executive function, memory function, and global cognition. Aerobic training prevailed, followed by resistance strength training and exergames. There was high variability in the characteristics of the protocols. The average length of interventions was 3–6 months; the frequency varied in the range of 1–4-times a week and 30–90 min sessions. The findings of this systematic review emphasise that physical fitness programs positively improve the specific domains of cognitive function in healthy older adults. These results can contribute to planning future interventions to improve the mental health of the older population and strengthen the development of policies for healthy ageing.