Relationships between physical activity, sleep and cognitive function: A narrative review

Physical activity and exercise can improve cognitive function and reduce the risk for dementia. Other lifestyle factors, including sleep, are associated with cognitive function and dementia risk, and exercise is an effective therapeutic strategy for improving sleep. Based on these associations, it has been hypothesised that sleep might be an important mediator for the effects of exercise on cognition. Here, we review the current literature to evaluate whether sleep and physical activity are independently or jointly associated with cognitive function. The extant literature in this area is minimal, and the causal relationships between physical activity, sleep and cognition have not been examined. A small number of cross-sectional studies in this area suggest that physical activity may attenuate some of the negative impact that poor sleep has on cognition, and also that sleep may be a mechanism through which physical activity improves cognitive abilities. Further research may enable the development of individually tailored intervention programs to result in the greatest cognitive benefit, ultimately delaying the onset of Alzheimer's disease.

Long-term Cognitive Trajectories and Mortality in Older Women

BACKGROUND

Few studies have examined whether change in cognition is linked to mortality. This study examined the relationship between cognitive trajectories in older age and risk of death.

METHODS

We studied community-dwelling, nondemented women aged 65+ (mean age = 71) enrolled in a prospective study of aging and followed up to 25 years. A modified Mini-Mental State Examination (mMMSE) and Trail Making Task Part B (TMTB) were administered at multiple visits during follow-up. We examined the association between cognitive trajectories (analyzed by quintiles) from baseline to age 80 (n = 7,477 for mMMSE and n = 6,503 for TMTB) and all-cause mortality after age 80 using Cox regression models, both unadjusted and adjusted for education, physical activity, alcohol, depression score, current smoking and history of hypertension and diabetes. Cause of death was determined from death certificates, classified as cardiovascular, cancer and other.

RESULTS

Women with greater rate of decline were older, less educated, less physically active, had higher depression score and were more likely to have a history of hypertension and diabetes (all p < .01). Participants with the greatest decline (quintile 1) had an increased risk of death (mMMSE hazard ratio [HR] = 1.28; TMTB HR = 1.43] and those with the least decline (quintile 5) had a decreased risk of death (mMMSE HR = 0.73; TMTB HR = 0.61) compared with intermediate decliners (quintiles 2-4). Cognitive trajectories were associated with cardiovascular mortality and other causes of death, but not cancer deaths.

CONCLUSIONS

Our study suggests that greater decline in general cognition or executive function is associated with higher rates of mortality in oldest-old women.

Identifying factors influencing cognitive outcomes after anodal transcranial direct current stimulation in older adults with and without cognitive impairment: A systematic review

Anodal transcranial direct current stimulation (tDCS) can improve cognition in healthy older adults, those with Alzheimer's disease (AD) and mild cognitive impairment (MCI), albeit with considerable variability in response. This systematic review identifies interindividual factors that may influence tDCS outcomes in older individuals with or without cognitive impairment. Peer-reviewed articles were included if they assessed whether cognitive outcomes (memory or global cognition) after tDCS were associated with pre-intervention factors in healthy older adults or individuals with AD/MCI. We identified eight factors that may affect cognitive outcomes after tDCS. Improved tDCS outcomes were predicted by lower baseline cognitive function when tDCS was combined with a co-intervention (but not when used alone). Preserved brain structure and better baseline functional connectivity, genetic polymorphisms, and the use of concomitant medications may predict better tDCS outcomes, but further research is warranted. tDCS outcomes were not consistently associated with age, cognitive reserve, sex, and AD risk factors. Accounting for individual differences in baseline cognition, particularly for combined interventions, may thus maximize the therapeutic potential of tDCS.

Neuropsychological Assessment and Screening in Heart Failure: a Meta-Analysis and Systematic Review

A variety of neuropsychological changes secondary to heart failure have been documented in the literature. However, what remains unclear are which neuropsychological abilities are the most impacted by heart failure and what tests have the sensitivity to measure that impact. Eight databases were searched for articles that examined the neuropsychological functioning of patients with heart failure. Some of the inclusion criteria were articles had to have a heart failure group with a demographically comparable control group and standardized neuropsychological testing. Exclusion criteria included articles with a heart failure group with any other type of major organ failure, or comparisons that were between different classes of heart failure rather than between a heart failure and non-heart failure group. A total of 33 articles met the inclusion criteria (total heart failure sample n = 8900) and provided effect size data for 20 neuropsychological domains. All observed domain-level differences between heart failure and non-heart failure groups were statistically significant, except for simple motor functioning and confrontation naming. The greatest differences in performance were in executive functioning, global cognition, complex psychomotor speed, and verbal memory. The highest effect sizes came from Trail-Making Test-Part B, CAMCOG, Symbol Digit Modality Test, and California Verbal Learning Test. The neuropsychological patterns of heart failure suggested diffuse cognitive involvement, with higher-level processes being most affected. It is important to track neurocognition in this clinical population since neuropsychological impairment is prevalent, and screening measures appear to be reliable. Such screening and further assessment would inform future medical treatment and may improve patient care management.

The Association Between Hair Cortisol, Hair Cortisone, and Cognitive Function in a Population-Based Cohort of Older Adults: Results From The Irish Longitudinal Study on Ageing

Experimental evidence to date largely supports an association between the stress hormone cortisol and cognitive performance. Older adults, in particular, may be vulnerable to the neurotoxic effects of prolonged increases in cortisol; however, the assessment of chronic hormone levels has previously been challenging. Hair cortisol analysis has advantages over other cortisol metrics for this purpose as it facilitates the assessment of total hormone secretion over several months. Cortisol and cortisone were measured in the scalp hair of 1,876 older adults from The Irish Longitudinal Study on Ageing. Participants underwent a battery of cognitive tests assessing global function, memory, executive function, and processing speed. After adjustment for hair characteristics, demographics, metabolic risk factors, cardiovascular conditions, and depression, regression analysis revealed an inverse relationship of hair glucocorticoids to immediate (cortisol: β = -.12, p = .032; cortisone: β = -.021, p = .036) and delayed (cortisol: β = -.13, p = .003; cortisone: β = -.23, p = .006) word recall performance. They were also associated with more errors on the Mini-Mental State Examination (cortisol: incidence rate ratio (IRR) = 1.06, p = .008; cortisone: IRR = 1.14, p = .002) and Montreal Cognitive Assessment (cortisone: IRR = 1.06, p = .015). Higher hair glucocorticoids are inversely associated with memory and global cognition in a population-based sample of older adults. Future work should explore the prognostic significance of these findings.

Global cognition modifies the relationship between anemia and depression in old age: A longitudinal analysis of the IMIAS Study

OBJECTIVES

To examine the relationship between anemia and depression and whether sex and global cognition modify this relationship over a 4-year follow-up.

DESIGN

Longitudinal analysis of an international cohort study SETTINGS AND PARTICIPANTS: Older adults from the International Mobility in Aging Study (IMIAS) aged between 65 and 74 years at baseline.

METHODS

Participants were recruited in Natal (Brazil), Manizales (Colombia), Kingston (Ontario, Canada), and Saint-Hyacinthe (Quebec, Canada). The study outcome was depression, defined by a score of ≥16 in the Center for Epidemiologic Studies Depression Scale. Longitudinal associations over a 4-year follow-up were examined using generalized estimating equations. Cognition was ascertained with the Leganes Cognitive Test with scores ≤ 22 indicating poor cognition. Models were also adjusted for research sites, marital status, alcohol drinking status, body mass index, chronic conditions, activities of daily life disabilities, and polypharmacy.

RESULTS

Anemia and poor cognition at baseline were associated with an increased risk of depression at follow-up (OR = 5.73, 95% CI: 1.58-20.78). Global cognition was also an effect modifier of the longitudinal association between the severity of anemia and depression.

CONCLUSIONS

In international samples of older adults, anemia, as well as the severity of anemia, were independent risk factors for depression, and the effect of these associations was modified by global cognition. The findings highlight an important issue as to whether depression in old age may be at least partially preventable through public health interventions to correct low Hb levels.

Association between oral health and cognitive function among Chinese older adults: the Taizhou imaging study

BACKGROUND

We aimed to investigate the association between oral health and cognitive function in a sample of older adults from a Chinese rural community.

METHODS

The cross-sectional cognitive function of 677 individuals were assessed by Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA). A comprehensive profile of the oral health status was evaluated by questionnaire and clinical examination.

RESULTS

Multiple covariates-adjusted regression models demonstrated decayed teeth (DT) and decayed/missing/filled teeth (DMFT) were negatively associated with MoCA score (all p < 0.05). Calculus index (CI) and clinical attachment loss (CAL) were significantly associated with the lower MoCA, short-term memory and executive function score, respectively (all p < 0.05). Additionally, participants with missing teeth unrestored tend to get lower MMSE and MoCA scores (p < 0.05). The results also showed that increased DT and CI were modestly associated with higher odds of cognitive impairment (p < 0.05).

CONCLUSIONS

There is an association between oral health and global cognition. Poor periodontal status was strongly associated with worse global cognition performance, especially in the short-term memory and executive domain for the aging population.

Emotion regulation in pediatric bipolar disorder: A meta-analysis of published studies

BACKGROUND

Emotion regulation is a relatively recent topic in psychiatry, and has only recently begun to be tested across Pediatric Bipolar Disorder (PBD). To date, no meta-analysis has investigated the presence of emotion regulation deficits in PBD patients.

OBJECTIVES

The aim of this study is to understand where the literature stands on this topic, as well as how different researchers are measuring and grasping the concept of emotion regulation in pediatric bipolar disorders.

METHODS

A systematic search of trials using the terms ("Pediatric Bipolar Disorder") AND ("Emotion Regulation" OR "Affect Regulation" OR "Mood Lability" OR "Mood Instability" OR "Irritability") was conducted using PubMed, Google Scholar, ResearchGate, Web of Science and Psych Info databases. Of the initial 366 articles identified, 8 met eligibility criteria for the meta-analysis and were included in this study.

RESULTS

There is a statistically significant difference in Accuracy in Emotion Regulation tasks, with a tendency for lower accuracy in PBD patients; however, both groups did not differ statistically regarding Response Time.

CONCLUSION

Our data suggests that PBD patients do present emotion regulation deficits, particularly regarding facial emotion recognition and affective language interference tasks mediated by cognitive assignments. These results have important implications in developing novel psychotherapeutic interventions for this population.

Association between intra-individual changes in social network diversity and global cognition in older adults: Does closeness to network members make a difference?

OBJECTIVE

Although qualitative aspects of interpersonal networks, such as diversity or closeness, can protect the health of older adults, their association with cognitive health remains unclear. This study examined the concurrent and time-lagged association between intra-individual changes in global cognition and social network diversity, while considering emotional closeness.

METHODS

In this 10-year study, we obtained six-wave, biennial data from the National Institute for Longevity Sciences, Longitudinal Study of Aging. Data from 808 community-dwelling, cognitively intact adults aged 65 or older at baseline were analyzed. Global cognition was assessed using the Mini-Mental State Examination (MMSE). Social network diversity scores were assessed using a social convoy model, comprising three closeness levels: inner (closest), middle (second closest), and outer (least close).

RESULTS

The mean age of the respondents was 72.0 ± 4.4 years at baseline, and 50.1% were male. A fixed-effects model showed that intra-individual change in total (coefficients, B: 0.10; standard error [SE]: 0.05; p = .042) and inner (B: 0.25; SE: 0.07; p < .001) social network diversity was significantly associated with MMSE score decline, even after adjusting for covariates. Yet, in time-lagged models, diversity and MMSE score changes were not significantly associated during the subsequent two years.

CONCLUSION

Older adults' global cognition declined when the diversity of their closest social network decreased. This may be a promising marker for early cognitive decline in older adults. Indeed, their closest networks are relatively unlikely to decline as part of normal aging or diseases except dementia.

Effects of cognitive stimulation program on cognition and mood in older adults, stratified by cognitive levels: A randomized controlled trial

PURPOSE OF THE RESEARCH

Cognitive stimulation (CS) is defined as activities that involve cognitive processing, usually conducted in a social context and often in a group. This study aims to evaluate the effects of a personalized-adapted CS program in older adults on global cognition, neuropsychological constructs, activities of daily living (ADLs), and mood.

MATERIALS AND METHODS

The randomized controlled single-blind trial involving 337 participants (235 women and 102 men) ≥ 65 years of age in a Primary Care centre classified participants into 4 groups: 101 for the no deterioration (ND) group; 100 for the subjective cognitive impairment (SCI) group; 108 for the level deterioration (LD) group and 28 for the moderate deterioration group. The intervention consisted of a personalized CS adapted program for 10 weeks. Follow-up assessments were conducted post-intervention, and at 6 and 12 months. The primary outcome was global cognition measured by the Spanish version of the Mini-Mental State Examination. The secondary outcomes were measured by the Barthel Index, the Lawton and Brody Scale, the Goldberg Questionnaire (anxiety sub-scale) and the abbreviated Yesavage Geriatric Depression Scale.

RESULTS

The intervention showed a tendency of improvement on global cognition and different cognitive functions for groups with no deterioration or level deterioration. The group with moderate deterioration improved in anxiety.

CONCLUSIONS

The findings demonstrated benefits in global cognition, different cognitive functions, semantic fluency, IADLs and anxiety. The most benefits are given in the intermediate groups, SCI, and LD. Moreover, the intervention works by increasing the benefits in the different phases.

Cognition in older age bipolar disorder: An analysis of archival data across the globe

BACKGROUND

Cognitive deficits in bipolar disorder (BD) impact functioning and are main contributors to disability in older age BD (OABD). We investigated the difference between OABD and age-comparable healthy comparison (HC) participants and, among those with BD, the associations between age, global cognitive performance, symptom severity and functioning using a large, cross-sectional, archival dataset harmonized from 7 international OABD studies.

METHODS

Data from the Global Aging and Geriatric Experiments in Bipolar Disorder (GAGE-BD) database, spanning various standardized measures of cognition, functioning and clinical characteristics, were analyzed. The sample included 662 euthymic to mildly symptomatic participants aged minimum 50years (509 BD, 153 HC), able to undergo extensive cognitive testing. Linear mixed models estimated associations between diagnosis and global cognitive performance (g-score, harmonized across studies), and within OABD between g-score and severity of mania and depressive symptoms, duration of illness and lithium use and of global functioning.

RESULTS

After adjustment for study cohort, age, gender and employment status, there was no significant difference in g-score between OABD and HC, while a significant interaction emerged between employment status and diagnostic group (better global cognition associated with working) in BD. Within OABD, better g-scores were associated with fewer manic symptoms, higher education and better functioning.

LIMITATIONS

Cross-sectional design and loss of granularity due to harmonization.

CONCLUSION

More research is needed to understand heterogenous longitudinal patterns of cognitive change in BD and understand whether particular cognitive domains might be affected in OABD in order to develop new therapeutic efforts for cognitive dysfunction OABD.

Associations between ApoE gene and psychological consequences post stroke in a Bahraini cohort

BACKGROUND

The contribution of genetic factors such as the presence of ApoE allele e4 and its association with psychological consequences post stroke remains unknown within Middle-Eastern regions. This study examined the association of ApoE genotype with cognitive impairment and mood in stroke patients and compare with healthy older adults in Bahrain.

METHOD

A prospective sample of n = 62 stroke patients (case group) and n = 53 healthy ageing individuals (control group) were eligible to participate in the study. A neuropsychological battery of cognitive assessments were conducted on all participants, and then stratified by cognitive function: no cognitive impairment, mild cognitive impairment and moderate to severe cognitive impairment. Anxiety and depression were assessed using the Hospital Anxiety and Depression Scale (HADS).

RESULTS

Most frequent ApoE genotype was e2/e3 in case (44%) and control groups (63%). ApoE allele e3 had the highest frequency for both groups with all stroke patients presenting with this allele and 86% for the control group (χ²  = 12.14, p < .0001). Stroke patients' non-carriers for ApoE allele e4 performed better on all cognitive measures but differences were not statistically significant (ns). Carriers of ApoE allele e2 in both groups had less mood symptoms compared to non-carriers.

DISCUSSION

ApoE genotype e3/e4 and e4/e4 was low in this Bahraini cohort explaining why there may been no significant associations found for this genotype variant with cognitive impairment. Further investigation of cognitive impairment and mood dysregulation with the different variants of the ApoE gene in general ageing and stroke populations is required from different ethno-cultural groups and geographical regions globally.

Longitudinal study of speech and dual-task performance in Parkinson's disease patients treated with subthalamic nucleus deep brain stimulation

INTRODUCTION

Impairments in speech and executive functions are both observed in Parkinson's disease (PD) and might be influenced by subthalamic nucleus deep brain stimulation (STN-DBS). We investigated the effects of STN-DBS on speech and executive functions and their mutual interference in PD.

METHODS

14 PD patients eligible for bilateral STN-DBS (PD-DBS), and 16 PD patients with best medical treatment (PD-BMT) were included. Global cognition, executive functions (inhibition and verbal fluency), speech tasks with acoustic measures, and a dual-task (DT) combining a speech task with a Go or Go/NoGo task were performed at baseline and 12 months follow-up. A normative group of matched healthy participants was included at baseline for the evaluation of speech and DT performance.

RESULTS

In both patient groups, global cognition mildly decreased after 12 months (p < .001). PD-DBS showed decreased inhibition (p = .016) whereas PD-BMT deteriorated in vowel articulation (p = .011). Using the DT paradigm, PD-DBS showed a slowing of speech rate after 12 months (p = .009) in contrast to PD-BMT (p = .203).

CONCLUSION

STN-DBS does not seem to impair speech and global cognition but might affect certain executive functions (notably inhibition). Speech-cognition interference is relatively preserved in PD patients, even though PD-DBS present larger DT cost on speech rate at 12 months post-DBS compared to PD-BMT. An evaluation with a longer follow-up using a larger sample is needed to confirm long-term effects.

Increased perivascular space volume in white matter and basal ganglia is associated with cognition in Parkinson's Disease

Perivascular spaces (PVS), fluid-filled compartments surrounding brain vasculature, are an essential component of the glymphatic system responsible for transport of waste and nutrients. Glymphatic system impairment may underlie cognitive deficits in Parkinson's disease (PD). Studies have focused on the role of basal ganglia PVS with cognition in PD, but the role of white matter PVS is unknown. This study examined the relationship of white matter and basal ganglia PVS with domain-specific and global cognition in individuals with PD. Fifty individuals with PD underwent 3T T1w magnetic resonance imaging (MRI) to determine PVS volume fraction, defined as PVS volume normalized to total regional volume, within (i) centrum semiovale, (ii) prefrontal white matter (medial orbitofrontal, rostral middle frontal, superior frontal), and (iii) basal ganglia. A neuropsychological battery included assessment of global cognitive function (Montreal Cognitive Assessment, and global cognitive composite score), and cognitive-specific domains (executive function, memory, visuospatial function, attention, and language). Higher white matter rostral middle frontal PVS was associated with lower scores in both global cognitive and visuospatial function. In the basal ganglia higher PVS was associated with lower scores for memory with a trend towards lower global cognitive composite score. While previous reports have shown that greater amount of PVS in the basal ganglia is associated with decline in global cognition in PD, our findings suggest that increased white matter PVS volume may also underlie changes in cognition.

Discordant Biological and Chronological Age: Implications for Cognitive Decline and Frailty

BACKGROUND

Older adults with discordant biological and chronological ages (BA and CA) may vary in cognitive and physical function from those with concordant BA and CA.

METHODS

To make our approach clinically accessible, we created easy-to-interpret participant groups in the Health, Aging, and Body Composition Study (N = 2 458, 52% female participants, 65% White participants, age: 73.5 ± 2.8) based on medians of CA, and a previously validated BA index comprised of readily available clinical tests. Joint models estimated associations of BA-CA group with cognition (Modified Mini-Mental State Examination [3MS] and Digit Symbol Substitution Test [DSST]) and frailty over 10 years.

RESULTS

The sample included the following: 32%, Young group (BA and CA < median); 21%, Prematurely Aging group (BA ≥ median, CA < median), 27%, Old group (BA and CA ≥ median), and 20%, Resilient group (BA < median, CA ≥ median). In education-adjusted models of cognition, among those with CA < median, the Prematurely Aging group performed worse than the Young at baseline (3MS and DSST p < .0001), but among those with CA ≥ median, the Resilient group did not outperform the Old group (3MS p = .31; DSST p = .25). For frailty, the Prematurely Aging group performed worse than the Young group at baseline (p = .0001), and the Resilient group outperformed the Old group (p = .003). For all outcomes, groups did not differ on change over time based on the same pairwise comparisons (p ≥ .40).

CONCLUSIONS

Discordant BA and CA identify groups who have greater cognitive and physical functional decline or are more protected than their CA would suggest. This information can be used for risk stratification.

A preliminary investigation of the clinical and cognitive correlates of circulating vitamin D in bipolar disorder

The role that vitamin D plays in the cognitive and clinical characteristics of bipolar disorder (BD) is unclear. We examined differences in the levels and deficiency status of vitamin D in an Australian sample of BD patients compared to healthy controls; and determined the extent to which vitamin D is associated with clinical variables and cognitive function in the sample. 22 healthy controls and 55 stable outpatients with a diagnosis of BD and low-grade mood symptomatology provided a sample of blood and completed cognitive tests and clinical measures. Plasma concentrations of 25-hydroxyvitamin D (vitamin D) were assayed and used to segregate participants into subgroups with sufficient or deficient levels of vitamin D. Subgroups were then compared in terms of global cognition and a range of sociodemographic and clinical factors (number of past mood episodes, illness duration, seasonal mood pattern, mood symptom severity), while mean levels of vitamin D were compared between patients and controls. Although almost 27% of the current sample were vitamin D deficient, no significant differences in mean vitamin D levels or the prevalence of vitamin D deficiency were evident between BD patients and controls. Vitamin D was not associated with global cognition in either patients or controls, nor any of the clinical measures assessed in the study. In conclusion, we observed no difference in the vitamin D levels and deficiency status of an Australian sample of healthy individuals and BD patients with low grade mood symptomatology compared to controls. Clinical symptoms and global cognition also appear to be independent of vitamin D levels in BD.

Comparative efficacy of seven nonpharmacological interventions on global cognition in older adults with and without mild cognitive impairment: a network meta-analysis of randomized controlled trials

To maintain current cognitive function and access greater cognitive reserves, nonpharmacological interventions may be a viable alternative for older adults with or without cognitive impairment. This study aimed to compare different nonpharmacological interventions for enhancing global cognition, including mind-body exercise, physical exercise, non-invasive brain stimulation, cognitive training intervention (CTI), acutherapy (ACU), meditation, and music therapy, by applying a network meta-analysis (NMA). Sixty-one randomized controlled trials evaluating the efficacy of interventions on global cognition in older adults with or without mild cognitive decline were selected. An NMA was conducted to compare the efficacy of different nonpharmacological interventions. The NMA revealed that mind-body exercise (standardized mean difference, 1.384; 95% confidence interval, 0.777-1.992); ACU (1.283; 0.478-2.088); meditation (0.910; 0.097-1.724); non-invasive brain stimulation (1.242; 0.254-2.230); CTI (1.269; 0.736-1.802); and physical exercise (0.977; 0.212-1.742), showed positive effects compared to passive controls. There were no significant differences between the efficacies of other interventions. Nonpharmacological interventions may potentially enhance and maintain global cognition through various pathways, such as memorizing movements and enhancing brain plasticity by reducing stress in the older adult population. Additional studies are needed to clarify the impact of other variables, including intervention methods or psychological variables.

Relationship between severe hypoglycemia or impaired awareness of hypoglycemia and diabetes-related health status, global cognition and executive functions in adults with type 1 diabetes without severe anxiety or depression

AIMS

To explore the relationship between impaired awareness of hypoglycemia (IAH) or severe hypoglycemia (SH), and health status and cognition in adults with type 1 diabetes (T1D).

METHODS

T1D adults attending a tertiary diabetes service were recruited into this cross-sectional study. People screening positive for severe anxiety or depression were not included. Hypoglycemia awareness status was assessed using the full-scale and factor 1 of the Minimally Modified Clarke Hypoglycemia Survey (MMCHS; ≥4 and ≥2 = IAH); and data collected on health status (Diabetes Health Profile: barriers to activity, BA; psychological distress, PD; disinhibited eating); global cognition (Montreal Cognitive Assessment); and executive functions (EF; INECO Frontal Screening, IFS). A score of reduced awareness in item 3 and/or 4 of the MMCHS defined experience of ≥1 SH in past 6-12 months.

RESULTS

In 165 T1D adults, prevalences of SH, IAH by MMCHS full-scale and factor 1 were 35%, 13% and 28%. Participants with IAH by factor 1 had higher scores for PD (p = 0.008). Participants with SH and IAH (full-scale or factor 1) had higher BA scores (all p < 0.05) but no impairment of global cognition or EF. Participant Z-score IFS was lower than in non-diabetic individuals (p < 0.001).

CONCLUSIONS

In our cohort, executive dysfunction in T1D was not associated with SH or IAH. IAH was associated with PD, and both SH and IAH were related to behavioral dysfunction.

Efficacy of Nonpharmacological Interventions in Cognitive Impairment: Systematic Review And Network Meta-Analysis

INTRODUCTION

There is currently no known cure for cognitive impairment, which highlights the need to explore other ways of managing this condition. This topic has recently become an area of active research. However, the availability of nonpharmacological options poses a challenge when trying to determine the best treatment for improving cognitive function.

METHODS

We conducted a systematic review and a Bayesian network meta-analysis to compare the effects of nonpharmacological interventions on global cognition in patients with mild cognitive impairment and dementia. The nonpharmacological interventions were classified as aerobic exercise, strength exercise, multicomponent physical exercise, other physical exercises, tai chi, mind-body exercises, traditional cognitive rehabilitation, computer-based cognitive rehabilitation, occupational therapy, music therapy, physical-cognitive rehabilitation, and reminiscence therapy.

RESULTS

Physical-cognitive rehabilitation emerged as the most effective nonpharmacological intervention for enhancing global cognition in patients with unspecified cognitive impairment and dementia, whereas occupational therapy focused on dual-task interventions was found to be the most effective nonpharmacological intervention for mild cognitive impairment.

CONCLUSION

These results underscore the importance of adopting a dual approach to managing cognitive impairment, integrating both cognitive and physical rehabilitation within the same intervention.

The Association Between Cognitive Domains and Postural Balance among Healthy Older Adults: A Systematic Review of Literature and Meta-Analysis

PURPOSE OF REVIEW

This review aims to explore which cognitive domain is more closely associated with which type of balance (static or dynamic).

RESENT FINDING

Based on recent reviews, inhibitory control, a part of cognition, plays a crucial role in balance performance. Previous reviews report significant links between cognition, mobility, and physical function in older adults. However, evidence regarding the relationship between cognition and balance scores remains inconclusive. The strength of association between cognition and balance appears to be domain-specific and task-specific. Executive function exhibits the strongest correlation with balance, while episodic memory shows a small link with dynamic balance. Processing speed and global cognition demonstrate moderate correlations. Additionally, there is a slight association between cognitive domains and static balance. Further research is needed to elucidate the underlying mechanisms and develop targeted interventions for managing balance-related concerns that are domain-specific and task-specific.

Cognitive decline is associated with frequency-specific resting state functional changes in normal aging

Resting state low-frequency brain activity may aid in our understanding of the mechanisms of aging-related cognitive decline. Our purpose was to explore the characteristics of the amplitude of low-frequency fluctuations (ALFF) in different frequency bands of fMRI to better understand cognitive aging. Thirty-seven cognitively normal older individuals underwent a battery of neuropsychological tests and MRI scans at baseline and four years later. ALFF from five different frequency bands (typical band, slow-5, slow-4, slow-3, and slow-2) were calculated and analyzed. A two-way ANOVA was used to explore the interaction effects in voxel-wise whole brain ALFF of the time and frequency bands. Paired-sample t-test was used to explore within-group changes over four years. Partial correlation analysis was performed to assess associations between the altered ALFF and cognitive function. Significant interaction effects of time × frequency were distributed over inferior frontal gyrus, superior frontal gyrus, right rolandic operculum, left thalamus, and right putamen. Significant ALFF reductions in all five frequency bands were mainly found in the right hemisphere and the posterior cerebellum; whereas localization of the significantly increased ALFF were mainly found in the cerebellum at typical band, slow-5 and slow-4 bands, and left hemisphere and the cerebellum at slow-3, slow-2 bands. In addition, ALFF changes showed frequency-specific correlations with changes in cognition. These results suggest that changes of local brain activity in cognitively normal aging should be investigated in multiple frequency bands. The association between ALFF changes and cognitive function can potentially aid better understanding of the mechanisms underlying normal cognitive aging.

Transcranial direct current stimulation for global cognition in Alzheimer's disease: a systemic review and meta-analysis

This meta-analysis was to investigate the efficacy of transcranial direct current stimulation (tDCS) for general cognitive function in Alzheimer's disease (AD) and to investigate the potential influential factors. A systematic literature retrieval until August 2023 was performed by searching the PubMed, Embase, Web of Science, and Cochrane Library. Therapeutic effects of tDCS were evaluated using standardized mean difference (SMD) and 95% confidence interval (CI). Pooled effects of tDCS on AD patients were calculated immediately after treatment and at follow-up periods. Subgroup analyses were conducted to identify the potential prognostic factors. Eleven studies with 12 trials including 451 cases were included in our systemic review, in which 9 studies with 10 trials using Mini-Mental State Examination (MMSE) scales were included in the meta-analysis. tDCS significantly improved global cognition in AD immediately after the treatment (SMD, 0.46; 95% CI, 0.25-0.66; P<0.0001), but not at the shorter or longer follow-up period. Subgroup analyses suggested significant global cognitive improvement in patients receiving stimulation on temporal lobes instead of left dorsolateral prefrontal cortex, and in cases receiving tDCS with current density ≥ 0.08 mA/cm2 rather than <0.08 mA/cm2. Compared with tDCS plus cognitive training (CT), tDCS without CT produced obvious cognitive enhancement. In addition, patients with lower education were more likely to benefit from tDCS. tDCS was effective in improving general cognition in AD after treatment. However, further randomized trials are warranted to validate its longer-term effects as well as our subgroup analyses results.

Physical activity intensity is associated with cognition and functional connectivity in Parkinson's disease

BACKGROUND

Cognitive impairment is common in Parkinson's disease (PD) and often leads to dementia, with no effective treatment. Aging studies suggest that physical activity (PA) intensity has a positive impact on cognition and enhanced functional connectivity may underlie these benefits. However, less is known in PD. This cross-sectional study examined the relationship between PA intensity, cognitive performance, and resting state functional connectivity in PD and whether PA intensity influences the relationship between functional connectivity and cognitive performance.

METHODS

96 individuals with mild-moderate PD completed a comprehensive neuropsychological battery. Intensity of PA was objectively captured over a seven-day period using a wearable device (ActiGraph). Time spent in light and moderate intensity PA was determined based on standardized actigraphy cut points. Resting-state fMRI was assessed in a subset of 50 individuals to examine brain-wide functional connectivity.

RESULTS

Moderate intensity PA (MIPA), but not light PA, was associated with better global cognition, visuospatial function, memory, and executive function. Individuals who met the WHO recommendation of ≥150 min/week of MIPA demonstrated better global cognition, executive function, and visuospatial function. Resting-state functional connectivity associated with MIPA included a combination of brainstem, hippocampus, and regions in the frontal, cingulate, and parietal cortices, which showed higher connectivity across the brain in those achieving the WHO MIPA recommendation. Meeting this recommendation positively moderated the associations between identified functional connectivity and global cognition, visuospatial function, and language.

CONCLUSION

Encouraging MIPA, particularly the WHO recommendation of ≥150 min of MIPA/week, may represent an important prescription for PD cognition.