Sleep Quality and Aging: A Systematic Review on Healthy Older People, Mild Cognitive Impairment and Alzheimer’s Disease

A 6-month educational program improves sleep behaviour in community-dwelling frail older adults: A randomised controlled trial

BACKGROUND

The prevalence of sleep-related issues among older adults is a significant concern, with half of the older population reporting these problems. Consequently, strategies to improve sleep are needed for this population. This study aims to assess the effects of a health educational program on sleep behaviour among pre-frail or frail older adults residing in the community and to explore possible associations with frailty.

METHODS

This randomised controlled trial (NCT05610605) included a total of 197 community-dwelling older adults with frailty/pre-frailty, divided into control (n = 88) and educational (n = 109) groups, were assessed at baseline, after the 6-month educational program (6 months), and 6 months after the intervention (12 months). The intervention comprised four group sessions and six follow-up phone calls, focusing on frailty, physical activity, dietary habits, and cognitive training. Sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI) and wrist-worn accelerometry.

RESULTS

At 6 months, a significant time-by-group interaction was found for self-reported [β = -0.449, 95%CI (-0.844, -0.053), p = 0.026] and accelerometer-measured [β = 0.505, 95%CI (0.085, 0.926), p = 0.019] sleep efficiency, showing improved sleep efficiency in the intervention group vs. controls. A significant time-by-group interaction at 6 months was noted for sleep awakenings [β = -0.402, 95%CI (-0.825, -0.020), p = 0.047]. The educational program led to a significant decrease in awakenings, while the control group experienced an increase. The change in the number of awakenings (Rs = 0.183, p = 0.020) at 6 months was significantly associated with changes in frailty. Moreover, a significant time-by-group interaction was reported at the 12-month assessment [β = -0.449, 95%CI (-0.844, -0.053), p = 0.026] for self-reported sleep quality, indicating better results in the intervention group compared to controls.

CONCLUSION

The educational program improved sleep quality and sleep efficiency while reducing the number of awakenings per night among community-dwelling frail older adults, offering a practical approach to addressing sleep-related challenges in this demographic.

Prevalence of sleep disturbances in people with mild cognitive impairment: A systematic review and meta-analysis

This review was performed to determine sleep disturbance prevalence in individuals with mild cognitive impairment (MCI). The MEDLINE, Embase, Cochrane Library, CINAHL, PsycINFO, and Web of Science databases were systematically searched from inception to January 20, 2024. Fifty-two studies fulfilling the eligibility criteria were included. However, six of these studies were excluded from data synthesis due to poor methodological quality. The subjective sleep disturbance prevalence among all individuals with MCI was 35.8 % (95 % CI: 31.9-39.7) across 44 studies, and the objective sleep disturbance prevalence was 46.3 % (95 % CI: 36.3-56.3) across 6 studies. Five studies examined TST and WASO, while three assessed SE. Among all potential objective assessments of sleep disturbance prevalence, only TST, WASO, and SE could be meta-analyzed in MCI because of the limited number of studies available. The estimated sleep disturbance prevalence differed significantly according to measurement method, geographical region, and research design. However, the data source did not significantly influence prevalence estimates. In meta-regression analysis, publication year, participant age, percentage of females, and study quality did not predict prevalence. As subjective and objective sleep disturbances are common in people with MCI, effective intervention strategies should be developed to alleviate them.

Intermittent Fasting: Socio-Economic Profile of Spanish Citizens Who Practice It and the Influence of This Dietary Pattern on the Health and Lifestyle Habits of the Population

Intermittent fasting (IF) is a dietary approach that has gained popularity in recent years. More and more Spanish people are following this eating pattern, which consists of alternating periods of fasting with periods of food intake. Its benefits include improved metabolic and vascular health and weight loss.

OBJECTIVES

1. To study the prevalence of IF among the Spanish population. 2. To explore how demographic factors influence the choice to adopt this dietary approach.

METHODS

A descriptive cross-sectional study was conducted on the Spanish population using the NutSo-HH questionnaire, which was constructed, validated, and disseminated by the research team through a non-probabilistic snowball sampling approach, collecting socio-demographic data and nutritional, social and lifestyle habits of the population.

RESULTS AND CONCLUSIONS

A valid sample of 22,181 people participated, of whom 4.59% (n = 1018) said they practiced IF. The data show that more middle-aged men than women practice IF. In addition, individuals who follow IF methods are less likely to have no control over their food intake, are less scared to gain weight and have a higher body image, but no differences were found related to unhealthy food and nights out. There were also no significant differences in terms of the level of education, income, size of municipality, or region of residence. In conclusion, a person who practices IF seems to have adopted a healthier lifestyle and social habits.

The role of cognitive flexibility on higher level executive functions in mild cognitive impairment and healthy older adults

BACKGROUND

Mild Cognitive Impairment (MCI) is a preclinical condition between healthy and pathological aging, which is characterized by impairments in executive functions (EFs), including cognitive flexibility. According to Diamond's model, cognitive flexibility is a core executive function, along with working memory and inhibition, but it requires the development of these last EFs to reach its full potential. In this model, planning and fluid intelligence are considered higher-level EFs. Given their central role in enabling individuals to adapt their daily life behavior efficiently, the goal is to gain valuable insight into the functionality of cognitive flexibility in a preclinical form of cognitive decline. This study aims to investigate the role of cognitive flexibility and its components, set-shifting and switching, in MCI. The hypotheses are as follows: (I) healthy participants are expected to perform better than those with MCI on cognitive flexibility and higher-level EFs tasks, taking into account the mediating role of global cognitive functioning; (II) cognitive flexibility can predict performance on higher-level EFs (i.e., planning and fluid intelligence) tasks differently in healthy individuals and those diagnosed with MCI.

METHODS

Ninety participants were selected and divided into a healthy control group (N = 45; mean age 64.1 ± 6.80; 66.6% female) and an MCI group (N = 45; mean age 65.2 ± 8.14; 40% female). Cognitive flexibility, fluid intelligence, planning, and global cognitive functioning of all participants were assessed using standardized tasks.

RESULTS

Results indicated that individuals with MCI showed greater impairment in global cognitive functioning and EFs performance. Furthermore, the study confirms the predictive role of cognitive flexibility for higher EFs in individuals with MCI and only partially in healthy older adults.

A randomized, controlled clinical trial demonstrates improved owner-assessed cognitive function in senior dogs receiving a senolytic and NAD+ precursor combination

Age-related decline in mobility and cognition are associated with cellular senescence and NAD + depletion in dogs and people. A combination of a novel NAD + precursor and senolytic, LY-D6/2, was examined in this randomized controlled trial. Seventy dogs with mild to moderate cognitive impairment were enrolled and allocated into placebo, low or full dose groups. Primary outcomes were change in cognitive impairment measured with the owner-reported Canine Cognitive Dysfunction Rating (CCDR) scale and change in activity measured with physical activity monitors. Fifty-nine dogs completed evaluations at the 3-month primary endpoint, and 51 reached the 6-month secondary endpoint. There was a significant difference in CCDR score across treatment groups from baseline to the primary endpoint (p = 0.02) with the largest decrease in the full dose group. No difference was detected between groups using in house cognitive testing. There were no significant differences between groups in changes in measured activity. The proportion of dogs that improved in frailty and owner-reported activity levels and happiness was higher in the full dose group than other groups, however this difference was not significant. Adverse events occurred equally across groups. All groups showed improvement in cognition, frailty, and activity suggesting placebo effect and benefits of trial participation. We conclude that LY-D6/2 improves owner-assessed cognitive function over a 3-month period and may have broader, but more subtle effects on frailty, activity and happiness as reported by owners.

Sensational Dreams: The Prevalence of Sensory Experiences in Dreaming

Dreaming, a widely researched aspect of sleep, often mirrors waking-life experiences. Despite the prevalence of sensory perception during wakefulness, sensory experiences in dreams remain relatively unexplored. Free recall dream reports, where individuals describe their dreams freely, may not fully capture sensory dream experiences. In this study, we developed a dream diary with direct questions about sensory dream experiences. Participants reported sensory experiences in their dreams upon awakening, over multiple days, in a home-based setting (n = 3476 diaries). Our findings show that vision was the most common sensory dream experience, followed by audition and touch. Olfaction and gustation were reported at equally low rates. Multisensory dreams were far more prevalent than unisensory dreams. Additionally, the prevalence of sensory dream experiences varied across emotionally positive and negative dreams. A positive relationship was found between on the one hand sensory richness and, on the other emotional intensity of dreams and clarity of dream recall, for both positive and negative dreams. These results underscore the variety of dream experiences and suggest a link between sensory richness, emotional content and dream recall clarity. Systematic registration of sensory dream experiences offers valuable insights into dream manifestation, aiding the understanding of sleep-related memory consolidation and other aspects of sleep-related information processing.

Sex Differences in the Role of Sleep on Cognition in Older Adults

Study Objectives

The study aimed to investigate sex differences in the relationship between sleep quality (self-report and objective) and cognitive function across three domains (executive function, verbal memory, and attention) in older adults.

Methods

We analyzed cross-sectional data from 207 participants with normal cognition or mild cognitive impairment (89 males and 118 females) aged over 60. The relationship between sleep quality and cognitive performance was estimated using generalized additive models. Objective sleep was measured with the GT9X Link Actigraph, and self-reported sleep was measured with the Pittsburgh Sleep Quality Index.

Results

We found that females exhibited stable performance of executive function with up to about 400 minutes of total sleep time, with significant declines in performance (p = 0.02) when total sleep time was longer. Additionally, a longer total sleep time contributed to lower verbal memory in a slightly non-linear manner (p = 0.03). Higher self-reported sleep complaints were associated with poorer executive function in females with normal cognition (p = 0.02). In males, a positive linear relationship emerged between sleep efficiency and executive function (p = 0.04), while self-reported sleep was not associated with cognitive performance in males with normal cognition.

Conclusions

Our findings suggest that the relationships between sleep quality and cognition differ between older males and females, with executive function being the most influenced by objective and self-reported sleep. Interventions targeting sleep quality to mitigate cognitive decline in older adults may need to be tailored according to sex, with distinct approaches for males and females.

Socially-supported sleep in older adults aged 50 and older: a concept analysis

Introduction

The population of older adults is growing disproportionately, constituting 13% of the global population in 2022, and is expected to double by 2050. One of public health's priorities is healthy aging, the maintenance of functional ability aligned with well-being. As many as 50% of older adults report poor sleep quality, leading to an increased risk of morbidity and mortality. The quality and quantity of social relationships may broadly benefit sleep in older adults. However, the concept of socially-supported sleep is underdeveloped as a basis for intervention.

Methods

Existing literature was searched without time restriction in PubMed, CINAHL, PsycINFO, and Scopus ending in August 2022. Thematic analysis was used to determine the defining attributes, antecedents, and consequences of socially-supported sleep guided by Rodgers' evolutionary concept analysis.

Results

Twenty-nine articles written in English, peer-reviewed, and examined social support and sleep in participants aged ≥50 were included. The defining attributes reflect dimensions of sleep quality. The antecedents are safe and secure, belonging and connection, and warmth and comfort. The consequences of socially-supported sleep include improved regulatory capabilities, physical and emotional well-being, and quality of life.

Conclusion

Socially-supported sleep has the potential to inform interventions that promote sleep in older adults. Ongoing research is needed to address the antecedents and mechanisms through which socially-supported sleep may promote sleep quality for healthy aging.

Association Between Sleep Efficiency Variability and Cognition Among Older Adults: Cross-Sectional Accelerometer Study

Background

Sleep efficiency is often used as a measure of sleep quality. Getting sufficiently high-quality sleep has been associated with better cognitive function among older adults; however, the relationship between day-to-day sleep quality variability and cognition has not been well-established.

Objective

We aimed to determine the relationship between day-to-day sleep efficiency variability and cognitive function among older adults, using accelerometer data and 3 cognitive tests.

Methods

We included older adults aged >65 years with at least 5 days of accelerometer wear time from the National Health and Nutrition Examination Survey (NHANES) who completed the Digit Symbol Substitution Test (DSST), the Consortium to Establish a Registry for Alzheimer's Disease Word-Learning subtest (CERAD-WL), and the Animal Fluency Test (AFT). Sleep efficiency was derived using a data-driven machine learning algorithm. We examined associations between sleep efficiency variability and scores on each cognitive test adjusted for age, sex, education, household income, marital status, depressive symptoms, diabetes, smoking habits, alcohol consumption, arthritis, heart disease, prior heart attack, prior stroke, activities of daily living, and instrumental activities of daily living. Associations between average sleep efficiency and each cognitive test score were further examined for comparison purposes.

Results

A total of 1074 older adults from the NHANES were included in this study. Older adults with low average sleep efficiency exhibited higher levels of sleep efficiency variability (Pearson r=-0.63). After adjusting for confounding factors, greater average sleep efficiency was associated with higher scores on the DSST (per 10% increase, β=2.25, 95% CI 0.61 to 3.90) and AFT (per 10% increase, β=.91, 95% CI 0.27 to 1.56). Greater sleep efficiency variability was univariably associated with worse cognitive function based on the DSST (per 10% increase, β=-3.34, 95% CI -5.33 to -1.34), CERAD-WL (per 10% increase, β=-1.00, 95% CI -1.79 to -0.21), and AFT (per 10% increase, β=-1.02, 95% CI -1.68 to -0.36). In fully adjusted models, greater sleep efficiency variability remained associated with lower DSST (per 10% increase, β=-2.01, 95% CI -3.62 to -0.40) and AFT (per 10% increase, β=-.84, 95% CI -1.47 to -0.21) scores but not CERAD-WL (per 10% increase, β=-.65, 95% CI -1.39 to 0.08) scores.

Conclusions

Targeting consistency in sleep quality may be useful for interventions seeking to preserve cognitive function among older adults.

Trajectories of sleep duration and quality and their association with mild cognitive impairment, frailty, and all-cause mortality

OBJECTIVES

To identify longitudinal trajectories of sleep duration and quality and estimate their association with mild cognitive impairment, frailty, and all-cause mortality.

METHODS

We used data from three waves (2009, 2014, 2017) of the WHO Study on Global Aging and Adult Health in Mexico. The sample consisted of 2722 adults aged 50 and over. Sleep duration and quality were assessed by self-report. Sleep trajectories were determined by applying growth mixture models. Mixed-effects logistic (mild cognitive impairment) and ordinal logistic (frailty), and Cox proportional hazards (all-cause mortality) models were fitted.

RESULTS

Three classes for sleep duration ("optimal-stable," "long-increasing," and "short-decreasing") and quality ("very good-increasing," "very good-decreasing," and "moderate/poor stable") were identified. Compared to the optimal-stable group, the long-increasing trajectory had greater odds for mild cognitive impairment (odds ratio=1.68, 95% CI: 1.01-2.78) and frailty (odds ratio=1.66, 95% CI: 1.13-2.46), and higher risk for all-cause mortality (hazard ratio=1.91, 95% CI: 1.14-3.19); and the short-decreasing class had a higher probability of frailty (odds ratio=1.83, 95% CI: 1.26-2.64). Regarding the sleep quality, the moderate/poor stable trajectory had higher odds of frailty (odds ratio=1.71, 95% CI: 1.18-2.47) than very good-increasing group.

CONCLUSIONS

These results have important implications for clinical practice and public health policies, given that the evaluation and treatment of sleep disorders need more attention in primary care settings. Interventions to detect and treat sleep disorders should be integrated into clinical practice to prevent or delay the appearance of alterations in older adults' physical and cognitive function. Further research on sleep quality and duration is warranted to understand their contribution to healthy aging.

Better Life's Essential 8 contributes to slowing the biological aging process: a cross-sectional study based on NHANES 2007-2010 data

Objective

To investigate the relationship between Life's Essential 8 (LE8) and Phenotypic Age Acceleration (PhenoAgeAccel) in United States adults and to explore the impact of LE8 on phenotypic biological aging, thereby providing references for public health policies and health education.

Methods

Utilizing data from the National Health and Nutrition Examination Survey (NHANES) conducted between 2007 and 2010, this cross-sectional study analyzed 7,339 adults aged 20 and above. Comprehensive assessments of LE8, PhenoAgeAccel, and research covariates were achieved through the integration of Demographics Data, Dietary Data, Laboratory Data, and Questionnaire Data derived from NHANES. Weighted generalized linear regression models and restricted cubic spline plots were employed to analyze the linear and non-linear associations between LE8 and PhenoAgeAccel, along with gender subgroup analysis and interaction effect testing.

Results

(1) Dividing the 2007-2010 NHANES cohort into quartiles based on LE8 unveiled significant disparities in age, gender, race, body mass index, education level, marital status, poverty-income ratio, smoking and drinking statuses, diabetes, hypertension, hyperlipidemia, phenotypic age, PhenoAgeAccel, and various biological markers (p < 0.05). Mean cell volume demonstrated no intergroup differences (p > 0.05). (2) The generalized linear regression weighted models revealed a more pronounced negative correlation between higher quartiles of LE8 (Q2, Q3, and Q4) and PhenoAgeAccel compared to the lowest LE8 quartile in both crude and fully adjusted models (p < 0.05). This trend was statistically significant (p < 0.001) in the full adjustment model. Gender subgroup analysis within the fully adjusted models exhibited a significant negative relationship between LE8 and PhenoAgeAccel in both male and female participants, with trend tests demonstrating significant results (p < 0.001 for males and p = 0.001 for females). (3) Restricted cubic spline (RCS) plots elucidated no significant non-linear trends between LE8 and PhenoAgeAccel overall and in gender subgroups (p for non-linear > 0.05). (4) Interaction effect tests denoted no interaction effects between the studied stratified variables such as age, gender, race, education level, and marital status on the relationship between LE8 and PhenoAgeAccel (p for interaction > 0.05). However, body mass index and diabetes manifested interaction effects (p for interaction < 0.05), suggesting that the influence of LE8 on PhenoAgeAccel might vary depending on an individual's BMI and diabetes status.

Conclusion

This study, based on NHANES data from 2007-2010, has revealed a significant negative correlation between LE8 and PhenoAgeAccel, emphasizing the importance of maintaining a healthy lifestyle in slowing down the biological aging process. Despite the limitations posed by the study's design and geographical constraints, these findings provide a scientific basis for the development of public health policies focused on healthy lifestyle practices. Future research should further investigate the causal mechanisms underlying the relationship between LE8 and PhenoAgeAccel and consider cross-cultural comparisons to enhance our understanding of healthy aging.

Public perception on active aging after COVID-19: an unsupervised machine learning analysis of 44,343 posts

Introduction

To analyze public perceptions of active aging in China on mainstream social media platforms to determine whether the "14th Five Year Plan for the Development of the Aging Career and Older Adult Care System" issued by the CPC in 2022 has fully addressed public needs.

Methods

The original tweets posted on Weibo between January 1, 2020, and June 30, 2022, containing the words "aging" or "old age" were extracted. A bidirectional encoder representation from transformers (BERT)-based model was used to generate themes related to this perception. A qualitative thematic analysis and an independent review of the theme labels were conducted by the researchers.

Results

The findings indicate that public perceptions revolved around four themes: (1) health prevention and protection, (2) convenient living environments, (3) cognitive health and social integration, and (4) protecting the rights and interests of the older adult.

Discussion

Our study found that although the Plan aligns with most of these themes, it lacks clear planning for financial security and marital life.

Association of Sleep Status With Cognitive Functions in Centenarians: Evidence From Hainan Centenarian Cohort

OBJECTIVES

This study aimed to analyze the association between sleep quality, sleep duration, and cognitive functions among centenarians.

METHODS

The baseline data of the China Hainan Centenarians Cohort Study served as the foundation for this study. Logistic regression was utilized to demonstrate the relationship between sleep status and cognitive impairment. Moreover, a canonical correlation analysis was performed to analyze the correlation between these variables.

RESULTS

A total of 994 centenarians were included. After adjustment, poor sleep quality centenarians had an odds ratio of 1.77 (95% confidence interval [CI]: 1.00-3.09) for cognitive impairment when compared to centenarians with normal sleep quality. Centenarians who slept for more than 9 hr had a stronger association with severe cognitive impairment, indicated by an odds ratio of 1.41 (95% CI: 1.02-1.96), compared to those who slept for 7-9 hr. Additionally, the canonical correlation analysis results revealed that the linear combination of sleep quality V1, primarily determined by sleep latency, daytime dysfunction, and subjective sleep quality, was associated with cognitive function; the linear combination of cognitive function W1, mainly determined by orientation, attention and calculation, and memory.

DISCUSSION

There exists a correlation between poor sleep quality and cognitive impairment in centenarians, as well as a correlation between sleep duration >9 hr at night and severe cognitive impairment. The primary cognitive domains associated with sleep quality are orientation, calculation, and memory. It is imperative to monitor and safeguard the cognitive functions linked to poor sleep quality in the older individuals, with attention to orientation, calculation, and memory.

Actigraphy Estimated Sleep Moderates the Relationship between Physical Activity and Cognition in Older Adults

Background and Aims

Physical inactivity and poor sleep are common in older adults and may interact to contribute to age- and disease-related cognitive decline. However, prior work regarding the associations among physical activity, and cognition in older adults is primarily limited to subjective questionnaires that are susceptible to inaccuracies and recall bias. Therefore, this study examined whether objectively measured physical activity and sleep characteristics, each estimated using actigraphy, are independently or interactively associated with cognitive performance.

Methods

The study included 157 older adults free of dementia (136 cognitively unimpaired; 21 MCI; M age = 71.7) from the BIOCARD cohort.

Results

Using multiple linear regression, cognition was regressed on estimated total volume of physical activity (TVPA), sleep efficiency (SE), wake after sleep onset (WASO), and total sleep time (TST) (adjusted for age, sex, education, diagnosis, vascular risk factors, and Apolipoprotein E (APOE)-e4 genetic status). Models were also run for domain-specific cognitive composite scores. TVPA and SE each were positively associated with a global cognitive composite score. TVPA was positively associated with executive function and language composites, and SE was positively related to executive function, visuospatial, and language composites. Importantly, a TVPA by SE interaction (p = 0.015) suggested that adults with the poorest SE experienced the greatest benefit from physical activity in relation to global cognition. The other sleep metrics were unrelated to cognitive performance.

Conclusion

These results suggest that TVPA and SE may synergistically benefit cognition in older adults.

The relationship between social support and sleep quality in older adults: A review of the evidence

OBJECTIVES

Sleep quality is crucial for the health and well-being of older adults, and social support has been consistently shown to be related to sleep quality. However, there is a need for research to understand the mechanisms through which these two factors are linked. The purpose of this review is to synthesize scientific literature on the relationship between social support and sleep quality in older adults.

METHODS

Using an integrative review method, this review was conducted for a period from January 2012 to November 2022 using a combination of keywords related to social support and sleep quality in older adults.

RESULTS

A total of 21 studies that met the inclusion criteria were included. Social support was found to have a positive relationship with subjective and objective sleep quality. It may act as both a mediator between insomnia and hopelessness and a moderator buffering the influence of rumination and negative emotions on sleep quality.

CONCLUSION

This review provides evidence for the positive relationship between social support and sleep quality in older adults. Based on the findings of this review, healthcare professionals should prioritize incorporating assessments of social support and implementing interventions aimed at enhancing social support in older adults to improve their sleep quality.

[Structured case conference for sleep disturbances in nursing home residents with cognitive impairment]

Structured case conference for sleep disturbances in nursing home residents with cognitive impairment Abstract: Background: Nursing home residents living with cognitive impairment often suffer from sleep disturbances. Pharmacological interventions are not recommended to be the first-choice therapy. In general, a wide variance of non-pharmacological interventions is available, but no clearly suitable intervention can currently be specified. Aim: The case report presents the procedure of a structured analysis to support the selection of non-pharmacological interventions to promote sleep. Methods: A structured case conference was held using a developed case management template to draw up an individual intervention plan. Results: Based on the description of the situation and the determination of causes, different interventions from six main topics were planned: "offering appropriate activations during daytime", "creating bedtime routines", "checking the sleep environment", "observation of potential physical and psychological causes", "reflection on night care routines", and "use of drug therapies only in exceptional cases". Conclusions: For a successful management of sleep disturbances in nursing home residents living with cognitive impairment, it is essential that the specific sleep-related symptoms and causes are assessed systematically and interprofessionally to be able to work towards an improvement with appropriate measures. In order to obtain adequate solutions, evidence-based expertise should be taken into consideration.

Pilot study of a high-intensity interval training program in older adults: Safety, feasibility, functional fitness and cognitive effects

Exercise can boost physical and cognitive health in older adults. However, there are a lack of accessible exercise programs that foster adherence among older adults. In this study, we aimed to establish the safety and feasibility of APEX, a new exercise program designed to optimize fitness and cognitive gains for older adults, in addition to evaluating its acute physiological effects, and assessing its possible effects on functional fitness and cognition among healthy older adults. APEX utilizes a multimodal progressive high-intensity interval training (HIIT) design, with high-intensity intervals focused on enhancing cardiovascular fitness and muscle strength, and recovery intervals that incorporate balance and mobility exercises. The APEX training was tested in healthy older adults (n=4) over the course of four weeks. Ultimately, APEX was found to be safe and feasible, with no adverse events and high adherence. Participants met heart rate targets for all of the high-intensity exercises, and all intervals had a significant difference in heart rates between high-intensity and recovery periods in linear effects models (p<0.001). Improvements in functional fitness were observed in aerobic endurance, lower body strength, and balance. The intervention was also associated with positive trends in the cognitive domains of information processing, working memory, executive control, and attention. APEX offers a promising alternative to traditional cardiovascular exercise modalities for older adults with additional benefits for functional fitness and cognition. These results encourage further testing of the APEX program in older adults and different clinical populations.

Knowledge Structure and Emerging Trends of Mild Cognitive Impairment with Dyssomnias in Recent 20 Years: A Bibliometric Analysis via CiteSpace and VOSviewer

Background

Mild cognitive impairment (MCI), an intermediate stage between normal aging and dementia, has emerged as a prominent research area in geriatric care due to its heightened propensity for progressing toward dementia. Sleep plays a pivotal role in cognitive function, with dyssomnias not only exacerbating cognitive and affective symptoms associated with neurodegenerative diseases but also contributing to disease progression.

Aim

This bibliometric analysis investigates the global research on MCI with dyssomnias over the past two decades, aiming to discern key findings, research domains, and emerging trends in this field.

Methods

In this study, a bibliometric analysis was conducted using the search terms "MCI" and "sleep". Data were extracted from the Web of Science Core Collection database, and visualization and collaborative analysis were performed using CiteSpace and VOSviewer.

Results

This study encompassed 546 publications from 2003 to 2023. The publication volume and citation rate consistently increased over time. Neurosciences, Clinical Neurology, and Geriatrics Gerontology emerged as the top three research fields. The Journal of Alzheimer's Disease had the highest publication count, while Sleep Medicine received the most citations. USA, China, and Italy led in publication output. Collaborative clusters among authors and institutions were identified, but cooperation between clusters was limited. Active cocited reference clusters included "obstructive sleep apnea", "possible mediating pathways", and "isolated rapid eye movement sleep behaviour disorder". The top frequently mentioned keywords, besides "MCI", were "Alzheimer's disease", "dementia", "risk factor", and "Parkinson's Disease". Notable keyword clusters spanned circadian rhythm, Parkinson's disease, MCI, dementia with Lewy body, subjective cognitive impairment, Lewy body disease, Alzheimer's disease, and dietary patterns.

Conclusion

The field of MCI with dyssomnias is rapidly expanding, encompassing a wide range of neurodegenerative disorders and sleep disturbances. Current research endeavors are primarily focused on elucidating the underlying pathogenesis, predicting disease progression, and developing innovative treatment strategies for individuals affected by MCI with dyssomnias.

Mechanisms of multi-omics and network pharmacology to explain traditional chinese medicine for vascular cognitive impairment: A narrative review

BACKGROUND

The term "vascular cognitive impairment" (VCI) describes various cognitive conditions that include vascular elements. It increases the risk of morbidity and mortality in the elderly population and is the most common cognitive impairment associated with cerebrovascular disease. Understanding the etiology of VCI may aid in identifying approaches to target its possible therapy for the condition. Treatment of VCI has focused on vascular risk factors. There are no authorized conventional therapies available right now. The medications used to treat VCI are solely approved for symptomatic relief and are not intended to prevent or slow the development of VCI.

PURPOSE

The function of Chinese medicine in treating VCI has not yet been thoroughly examined. This review evaluates the preclinical and limited clinical evidence to comprehend the "multi-component, multi-target, multi-pathway" mechanism of Traditional Chinese medicine (TCM). It investigates the various multi-omics approaches in the search for the pathological mechanisms of VCI, as well as the new research strategies, in the hopes of supplying supportive evidence for the clinical treatment of VCI.

METHODS

This review used the Preferred Reporting Items for Preferred reporting items for systematic reviews and meta-analyses (PRISMA) statements. Using integrated bioinformatics and network pharmacology approaches, a thorough evaluation and analysis of 25 preclinical studies published up to July 1, 2023, were conducted to shed light on the mechanisms of TCM for vascular cognitive impairment. The studies for the systematic review were located using the following databases: PubMed, Web of Science, Scopus, Cochrane, and ScienceDirect.

RESULTS

We discovered that the multi-omics analysis approach would hasten the discovery of the role of TCM in the treatment of VCI. It will explore components, compounds, targets, and pathways, slowing the progression of VCI from the perspective of inhibiting oxidative stress, stifling neuroinflammation, increasing cerebral blood flow, and inhibiting iron deposition by a variety of molecular mechanisms, which have significant implications for the treatment of VCI.

CONCLUSION

TCM is a valuable tool for developing dementia therapies, and further research is needed to determine how TCM components may affect the operation of the neurovascular unit. There are still some limitations, although several research have offered invaluable resources for searching for possible anti-dementia medicines and treatments. To gain new insights into the molecular mechanisms that precisely modulate the key molecules at different levels during pharmacological interventions-a prerequisite for comprehending the mechanism of action and determining the potential therapeutic value of the drugs-further research should employ more standardized experimental methods as well as more sophisticated science and technology. Given the results of this review, we advocate integrating chemical and biological component analysis approaches in future research on VCI to provide a more full and objective assessment of the standard of TCM. With the help of bioinformatics, a multi-omics analysis approach will hasten the discovery of the role of TCM in the treatment of VCI, which has significant implications for the treatment of VCI.

The Association between Caffeine Consumption from Coffee and Tea and Sleep Health in Male and Female Older Adults: A Cross-Sectional Study

Poor sleep health is common in older adults and is associated with negative health outcomes. However, the relationship between caffeine consumption and sleep health at an older age is poorly understood. This study investigated the association between caffeine consumption and sleep health in community-dwelling older males and females in The Netherlands. Cross-sectional analyses were performed using data from 1256 participants aged 61-101 years from the Longitudinal Ageing Study Amsterdam. Self-reported questions assessed sleep disturbances (including sleep latency, continuity, and early awakening), sleep duration, and perceived sleep quality. Caffeine consumption was determined with questions about frequency, quantity, and type of coffee and tea consumption. Logistic and linear regression models were used, controlling for potential confounders, and interaction by sex and age was tested. Caffeine consumption showed significant interactions with sex (p < 0.005) in association with sleep health outcomes. Older females who abstained from caffeine consumption reported more sleep disturbances (β = 0.64 [95%CI 0.13; 1.15]) and had greater odds of short sleep duration (<7 h/day) (OR = 2.26 [95% CI 1.22; 4.20]) compared to those who consumed caffeine. No associations were observed for long sleep duration (>8 h/day) and perceived sleep quality. No associations were observed in older males. Caffeine abstinence was associated with more sleep disturbances and short sleep duration in older females, but not in males. The observed association in older females may reflect reverse causation, suggesting that females may have different motivations for discontinuing caffeine consumption than males.

Behavioral or neuropsychiatric symptoms of Alzheimer's disease: from psychopathology to pharmacological management

Neuropsychiatric or behavioral symptoms of dementia encompass a series of disorders, such as anxiety, depression, apathy, psychosis, and agitation, all commonly present in individuals living with dementia. While they are not required for the diagnosis of Alzheimer's disease (AD), they are ubiquitously present in all stages of the disease, contributing to negative clinical outcomes, including cognitive decline, functional disability, and caregiver burden. Neuropsychiatric symptoms have been conceptualized not only as risk factors but as clinical markers of decline along the AD spectrum. The concept of "mild behavioral impairment", the behavioral correlate of mild cognitive impairment, has been proposed within this framework. The first steps in the management of behavioral symptoms in AD involve defining the target and investigating potential causes and/or aggravating factors. Once these factors are addressed, non-pharmacological approaches are preferred as first-line interventions. Following the optimization of anticholinesterase treatments, specific pharmacological approaches (e.g., antidepressants, antipsychotics) can be considered weighing potential side effects.

Prevalence of sleep disturbances in people with mild cognitive impairment: a systematic review protocol

OBJECTIVE

This review will determine the prevalence of sleep disturbances in individuals with mild cognitive impairment.

INTRODUCTION

Mild cognitive impairment is regarded as a transitional state between normal functioning and dementia, and has a high likelihood of conversion to dementia. Individuals with mild cognitive impairment may suffer more severe sleep disturbances compared with normal older people. In some studies, sleep disturbances were associated with significantly higher odds of mild cognitive impairment. There is a need for prevalence estimates of sleep disturbances in people with mild cognitive impairment based on the currently available literature to guide clinical health care professionals and public health policies.

INCLUSION CRITERIA

The review will consider studies reporting on the prevalence of sleep disturbances in individuals with mild cognitive impairment, using validated instruments, including subjective and/or objective measures. Studies will be excluded if the participants report sleep-related breathing or movement disorders. Studies using only the Mini-Mental State Examination to diagnose mild cognitive impairment will also be excluded.

METHODS

The review will follow the JBI methodology for systematic reviews of prevalence and incidence. The MEDLINE (Ovid), Embase, Cochrane Library (CDSR and CENTRAL), CINAHL (EBSCOhost), PsycINFO (EBSCOhost), Scopus, and Web of Science Core Collection databases will be systematically searched from inception to the present with no language limitations. Analytical observational studies, including prospective and retrospective cohort, case-control, and cross-sectional studies, will be considered. Two reviewers will independently conduct the study selection, critical appraisal, and data extraction. Methodological quality will be evaluated using the JBI critical appraisal checklist for studies reporting prevalence data. A meta-analysis will be conducted to synthesize the prevalence data, where possible.

REVIEW REGISTRATION

PROSPERO CRD42022366108.

Sleep Disorders Associated with Neurodegenerative Diseases

Sleep disturbances are common in various neurological pathologies, including amyotrophic lateral sclerosis (ALS), multiple system atrophy (MSA), hereditary ataxias, Huntington's disease (HD), progressive supranuclear palsy (PSP), and dementia with Lewy bodies (DLB). This article reviews the prevalence and characteristics of sleep disorders in these conditions, highlighting their impact on patients' quality of life and disease progression. Sleep-related breathing disorders, insomnia, restless legs syndrome (RLS), periodic limb movement syndrome (PLMS), and rapid eye movement sleep behavior disorder (RBD) are among the common sleep disturbances reported. Both pharmacological and non-pharmacological interventions play crucial roles in managing sleep disturbances and enhancing overall patient care.

Association of sleep disorders with clinical symptoms and age in Chinese older adult patients with and without cognitive decline

Objective

To investigate correlation between cognitive function, age, and sleep disturbances.

Methods

This retrospective clinical study enrolled 78 patients with sleep disorders who were divided into three groups: a group of 24 patients with sleep disorders accompanied by cognitive decline (SD-CD); 54 patients with sleep disorders and no cognitive decline (SD-nCD) was divided into two groups, one of 30 patients aged between 60 and 70 years and another of 24 patients aged >70 years. Polysomnography was used to record patients' sleep indicators throughout night; these included total sleep duration, sleep efficiency (SE), sleep latency, sleep structure and percentage of N1, N2, and N3 stages, rapid eye movement (REM) stage, as well as apnea hypopnea index (AHI), and oxygen saturation (OS). Analysis of variance (ANOVA) for continuous variables and chi-square test for categorical variables were used to analyze variables between different groups. Pearson's correlation was used to analyze correlation between sleep parameters and mini-mental state examination (MMSE). Blood samples were used to determine their Aβ, Aβ40, Aβ42, total tau, phosphorylated tau protein (ptau), ptau181, ptau217, the inflammatory factor IL-1β, vitamin B12 (VB12), and melatonin levels.

Results

In the SD-CD group, there was a significant decrease in SE and an increase in N1 stage sleep in older patients and a significant increase in AHI, REM stage AHI, and non-REM stage AHI. In patients with SD-nCD, the minimum OS, minimum OS in the REM period, and minimum OS in the non-REM period were significantly reduced. OS was significantly correlated with cognitive level, as evaluated by the MMSE. The addition of sleep parameters can significantly improve the accuracy of dementia diagnosis. Dementia biomarkers of Aβ and tau proteins in blood showed cognition-related differences, while ptau181 was associated with both cognition and age-related differences. Regression models revealed that age was related to higher levels of cognitive decline before (β = -0.43, P < 0.001) and after (β = -0.38, P < 0.001) adjustment of gender, BMI, and education level. There was a significant mediation effect of relationship between aging and cognitive function by sleep efficiency and N1 stage sleep.

Conclusion

Sleep disorders and low OS are associated with a higher incidence of cognitive decline and dementia.

Hearables: Automatic Sleep Scoring from Single-Channel Ear-EEG in Older Adults

Sleep disorders are a prevalent problem among older adults, yet obtaining an accurate and reliable assessment of sleep quality can be challenging. Traditional polysomnography (PSG) is the gold standard for sleep staging, but is obtrusive, expensive, and requires expert assistance. To this end, we propose a minimally invasive single-channel single ear-EEG automatic sleep staging method for older adults. The method employs features from the frequency, time, and structural complexity domains, which provide a robust classification of sleep stages from a standardised viscoelastic earpiece. Our method is verified on a dataset of older adults and achieves a kappa value of at least 0.61, indicating substantial agreement. This paves the way for a non-invasive, cost-effective, and portable alternative to traditional PSG for sleep staging.

Depression is associated with worse health-related quality of life, lower physical activity levels, and inadequate sleep quality in a Greek elderly population

The present study is a cross-sectional study that aimed to investigate the potential associations between depression status, health-related quality of life, physical activity levels and sleep quality in a representative Greek elderly population. Three thousand four hundred five (3405) men and women over 65 years old from 14 different Greek regions were enrolled. Geriatric Depression Scale (GDS) was used to assess depression status, Health-Related Quality of Life (HRQOL) was evaluated using Short Form Health Survey, physical activity levels were assessed via the International Physical Activity Questionnaire (IPAQ) and sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI). A high prevalence of depression and an increased incidence of poor quality of life, low physical activity levels and inadequate sleep quality among the elderly population were recorded. Depression status was independently associated with worse quality of life, poor physical activity, inadequate sleep quality, female gender, BMI and living alone after adjustment for potential confounding factors. Elderly age, low muscle mass, educational and financial status were also identified as indicators of depression; however, their impact on depression status was considerably attenuated after adjusting for confounding factors. In conclusion, depression was associated with worse health-related quality of life, poor physical activity and inadequate sleep quality in a Greek elderly population. Future randomized control trials should be performed to confirm the findings of this cross-sectional study.

Malnutrition, Depression, Poor Sleep Quality, and Difficulty Falling Asleep at Night Are Associated with a Higher Risk of Cognitive Frailty in Older Adults during the COVID-19 Restrictions

The COVID-19 restrictions, such as social isolation and disruption of daily routines, can have detrimental effects, including increased stress, anxiety, sleep disturbance, and physical and cognitive decline among older adults. This study aimed to examine the association between nutritional status, depression, sleep quality, falling asleep at night, and cognitive frailty (CF) among older Thai adults during the COVID-19 pandemic. This cross-sectional study included 408 older adults with an average age of 70.54 (5.49) years. CF was determined using Fried's frailty phenotype and the Montreal Cognitive Assessment Basic. The Mini Nutritional Assessment-Short Form, Pittsburgh Sleep Quality Index, and geriatric depression assessment were used for assessment. Multiple logistic regression analysis demonstrated that participants who were malnourished (OR 3.786; 95%CI 1.719-8.335), depressed (OR 5.003; 95%CI 2.399-10.434), had poor sleep quality (OR 1.613; 95%CI 1.041-2.500), and engaged in difficulty falling asleep (OR 1.809; 95%CI 1.022-3.203) had a higher risk of CF compared to those who did not exhibit these factors. Therefore, malnutrition, depression, poor sleep quality, and difficulty falling asleep were identified as risk factors for CF among older adults in Thailand linked to the impact of the COVID-19 pandemic. It is crucial to develop interventions to prevent CF resulting from the mentioned variables.

The shared molecular mechanisms underlying aging of the brain, major depressive disorder, and Alzheimer's disease: The role of circadian rhythm disturbances

An association with circadian clock function and pathophysiology of aging, major depressive disorder (MDD), and Alzheimer's disease (AD) is well established and has been proposed as a factor in the development of these diseases. Depression and changes in circadian rhythm have been increasingly suggested as the two primary overlapping and interpenetrating changes that occur with aging. The relationship between AD and depression in late life is not completely understood and probably is complex. Patients with major depression or AD suffer from disturbed sleep/wake cycles and altered rhythms in daily activities. Although classical monoaminergic hypotheses are traditionally proposed to explain the pathophysiology of MDD, several clinical and preclinical studies have reported a strong association between circadian rhythm and mood regulation. In addition, a large body of evidence supports an association between disruption of circadian rhythm and AD. Some clock genes are dysregulated in rodent models of depression. If aging, AD, and MDD share a common biological basis in pathophysiology, common therapeutic tools could be investigated for their prevention and treatment. Nitro-oxidative stress (NOS), for example, plays a fundamental role in aging, as well as in the pathogenesis of AD and MDD and is associated with circadian clock disturbances. Thus, development of therapeutic possibilities with these NOS-related conditions is advisable. This review describes recent findings that link disrupted circadian clocks to aging, MDD, and AD and summarizes the experimental evidence that supports connections between the circadian clock and molecular pathologic factors as shared common pathophysiological mechanisms underlying aging, AD, and MDD.

Episodic and Semantic Autobiographical Memory in Mild Cognitive Impairment (MCI): A Systematic Review

INTRODUCTION

Mild cognitive impairment (MCI) is a syndrome defined as a decline in cognitive performance greater than expected for an individual according to age and education level, not interfering notably with daily life activities. Many studies have focused on the memory domain in the analysis of MCI and more severe cases of dementia. One specific memory system is represented by autobiographical memory (AM), which has been largely studied in Alzheimer's disease and its effect on AM; however, the impairment of AM in moderate forms of decline, such as MCI, is still controversial.

OBJECTIVE

The main aim of this systematic review is to analyze the functioning of autobiographical memory in patients with MCI, considering both the semantic and the episodic components.

MATERIALS

The review process was conducted according to the PRISMA statement. The search was conducted until 20 February 2023 in the following bibliographical databases: PubMed, Web of Science, Scopus, and PsycInfo, and twenty-one articles were included.

RESULTS

The results highlight controversial findings concerning the semantic component of AM since only seven studies have found a worse semantic AM performance in patients with MCI compared to the HC group. The results of impaired episodic AM in individuals with MCI are more consistent than those concerning semantic AM.

CONCLUSIONS

Starting from the evidence of this systematic review, further studies should detect and investigate the cognitive and emotional mechanisms that undermine AM performance, allowing the development of specific interventions targeting these mechanisms.

Association of sleep duration with underweight and obesity in older adults: A cross-sectional study of the Chinese longitudinal healthy longevity survey

OBJECTIVES

Underweight and obesity are two of the main health concerns as they are associated with adverse health outcomes and nutrition disorders. This study determined the association of sleep duration with both underweight and obesity in Chinese older adults.

METHODS

This cross-sectional secondary data analysis was conducted using data from the 2018 wave of the Chinese Longitudinal Healthy Longevity Survey. There were 13 917 participants aged 65 and above in the analysis. Body mass index (BMI) was categorized into underweight, normal weight and overweight, and obesity. Self-reported sleep duration was divided into short, normal, and long sleep duration. Logistic regression models were used to examine the association of sleep duration with underweight and obesity.

RESULTS

The prevalence of underweight was 16.7% and the prevalence of obesity was 8.0% in Chinese older adults aged 65 and older. Compared to the normal sleep duration group, the short sleep duration group had a higher incidence of underweight (AOR = 1.29, 95% CI: 1.01-1.65), and the long sleep duration group showed a higher incidence of obesity (AOR = 1.57, 95% CI: 1.07-2.30) in older men. A greater incidence of underweight was found in the short sleep duration group (AOR = 1.19, 95% CI: 1.02-1.40) in old-old adults after adjusting for covariates.

CONCLUSIONS

Short sleep duration is associated with being underweight and long sleep duration is linked with obesity in older men. Short sleep duration is also a risk factor for the underweight of old-old adults.

The Protective Role of Cognitive Reserve in Mild Cognitive Impairment: A Systematic Review

Cognitive reserve (CR) represents the ability to optimize performance and functioning to cope with brain damage or disease. CR reflects the capability to adaptively and flexibly use cognitive processes and brain networks to compensate for the deterioration typical of aging. Several studies have investigated the potential role of CR in aging, especially from the perspective of preventing and protecting against dementia and Mild Cognitive Impairment (MCI). This systematic literature review aimed to investigate the role of CR as a protective factor against MCI and associated cognitive decline. The review process was conducted according to the PRISMA statement. For this purpose, ten studies were analyzed. The results of this review show that high CR is significantly associated with a reduced risk of MCI. In addition, a significant positive relationship between CR and cognitive functioning is observed when comparing subjects with MCI and healthy subjects and within people with MCI. Thus, the results confirm the positive role of cognitive reserve in mitigating cognitive impairment. The evidence from this systematic review is consistent with the theoretical models of CR. Indeed, previous research hypothesized that specific individual experiences (such as leisure activities) allow a person to acquire successful neural resources over the years to cope with cognitive decline.

Do Sleep-Related Metacognitive Strategies Shape My Sleep? The Relationships between Strategies for Controlling Sleep-Related Intrusive Thoughts and Subjective and Objective Sleep Quality in Young Adulthood and Older Age

This study examined the associations between thought control strategies and subjective and objective sleep quality, across the adult lifespan. One hundred forty-nine individuals without insomnia (age range 18-86 years; M = 45.35, SD = 20.53) completed the Thought Control Questionnaire Insomnia-Revised for assessing sleep-related thought control strategies. Self-reported sleep quality was measured with the Pittsburgh Sleep Quality Index. Then, subjective and objective sleep parameters (i.e., total sleep time, sleep onset latency, sleep efficiency) were recorded through a sleep diary and an actigraph across 7 days. Results from linear mixed-effects models showed that a worry strategy was associated with longer subjective sleep latency and shorter subjective total sleeping time. An aggressive suppression strategy was associated with longer subjective total sleeping time. No such involvement of thought control strategies was detected for subjective sleep efficiency and all of the objective sleep parameters. Other individual differences (i.e., age, sex, circadian preference, self-reported sleep quality) also explained both subjective and objective sleep parameters, though to a different extent depending on the sleep parameter considered. The assessment of sleep-related thought control strategies, along with other individual characteristics, should be considered to account for individual differences in sleep quality and implement practices/interventions to support it in adulthood and older age.

Poor Sleep Quality in Aging: The Association with Mental Health

Sleep disturbances are common in the elderly. A primary sleep disorder can result from the physiological decline of aging; however, secondary sleep problems result from various causes involving physical and mental health. Since little is known about the relationships between sleep quality and mental health in aging, the present study aims to understand how different aspects generally associated with sleep (e.g., psychological and physiological factors, and sleep medication) may predict poor sleep quality in different stages of the lifespan. Therefore, we conducted several analyses (ANOVAs, Pearson correlations, and linear regressions) to test the hypotheses of the study. Accordingly, from a pool of 180 participants (elderly, middle-aged, and young adults), 143 individuals with poor sleep quality were selected. Different predictive patterns in the three groups emerged. Specifically, the use of sleep medication associated with worse sleep conditions is predicted by poor sleep quality in the elderly and by depression in young adults. In contrast, worsening sleep quality is predicted by depression in middle-aged adults. Previous studies focused on the transitions from good to poor sleep quality, while this is the first study to have examined the features of poor sleep quality in aging, highlighting different sleep patterns across the lifespan. This evidence should be considered from a preventive perspective.

Inherent regional brain activity changes in male obstructive sleep apnea with mild cognitive impairment: A resting-state magnetic resonance study

Obstructive sleep apnea (OSA) is the most common sleep disorder worldwide. Previous studies have shown that OSA patients are often accompanied by cognitive function loss, and the underlying neurophysiological mechanism is still unclear. This study aimed to determine whether there are differences in regional homogeneity (Reho) and functional connectivity (FC) across the brain between OSA patients with MCI (OSA-MCI) and those without MCI (OSA-nMCI) and whether such differences can be used to distinguish the two groups. Resting state magnetic resonance data were collected from 48 OSA-MCI patients and 47 OSA-nMCI patients. The brain regions with significant differences in Reho and FC between the two groups were identified, and the Reho and FC features were combined with machine learning methods for classification. Compared with OSA-nMCI patients, OSA-MCI patients showed significantly lower Reho in bilateral lingual gyrus and left superior temporal gyrus. OSA-MCI patients also showed significantly lower FC between the bilateral lingual gyrus and bilateral cuneus, left superior temporal gyrus and left middle temporal gyrus, middle frontal gyrus, and bilateral posterior cingulate/calcarine/cerebellar anterior lobe. Based on Reho and FC features, logistic regression classification accuracy was 0.87; sensitivity, 0.70; specificity, 0.89; and area under the curve, 0.85. Correlation analysis showed that MoCA scale score in OSA patients was significant positive correlation sleep efficiency and negatively correlation with neck circumference. In conclusion, our results showed that the OSA-MCI group showed decreased Reho and FC in specific brain regions compared with the OSA-nMCI group, which may help to understand the underlying neuroimaging mechanism of OSA leading to cognitive dysfunction and may serve as a potential biomarker to distinguish whether OSA is accompanied by cognitive impairment.

The complex burden of determining prevalence rates of mild cognitive impairment: A systematic review

Mild cognitive impairment (MCI) is a syndrome characterized by a decline in cognitive performance greater than expected for an individual's age and education level, but that does not interfere much with daily life activities. Establishing the prevalence of MCI is very important for both clinical and research fields. In fact, in a certain percentage of cases, MCI represents a prodromal condition for the development of dementia. Accordingly, it is important to identify the characteristics of MCI that allow us to predict the development of dementia. Also, initial detection of cognitive decline can allow the early implementation of prevention programs aimed at counteracting or slowing it down. To this end, it is important to have a clear picture of the prevalence of MCI and, consequently, of the diagnostic criteria used. According to these issues, this systematic review aims to analyze MCI prevalence, exploring the methods for diagnosing MCI that determine its prevalence. The review process was conducted according to the PRISMA statement. Three thousand one hundred twenty-one international articles were screened, and sixty-six were retained. In these studies, which involved 157,035 subjects, the prevalence of MCI ranged from 1.2 to 87%. The review results showed a large heterogeneity among studies due to differences in the subjects' recruitment, the diagnostic criteria, the assessed cognitive domains, and other methodological aspects that account for a higher range of MCI prevalence. This large heterogeneity prevents drawing any firm conclusion about the prevalence of MCI.