3-Month Melatonin Supplementation to Reduce Brain Oxidative Stress and Improve Sleep in Mild Cognitive Impairment: A Randomised Controlled Feasibility Trial.

Melatonin has multiple proposed therapeutic benefits including antioxidant properties, circadian rhythm synchronisation and sleep promotion. Since these areas are also recognised risk factors for dementia, melatonin has been hypothesised to slow cognitive decline in older adults. Participants with Mild Cognitive Impairment (MCI) were recruited from the community for a 12-week randomised placebo-controlled parallel, feasibility trial of 25 mg oral melatonin nightly.

Blood-Based Transcriptomic Biomarkers Are Predictive of Neurodegeneration Rather Than Alzheimer's Disease.

Alzheimer's disease (AD) is a growing global health crisis affecting millions and incurring substantial economic costs. However, clinical diagnosis remains challenging, with misdiagnoses and underdiagnoses being prevalent. There is an increased focus on putative, blood-based biomarkers that may be useful for the diagnosis as well as early detection of AD.

Region-specific changes in brain activity and memory after continuous positive airway pressure therapy in obstructive sleep apnea: a pilot high-density electroencephalography study.

Study Objectives: Limited channel electroencephalography (EEG) investigations in obstructive sleep apnea (OSA) have revealed deficits in slow wave activity (SWA) and spindles during sleep and increased EEG slowing during resting wakefulness. High-density EEG (Hd-EEG) has also detected local parietal deficits in SWA (delta power) during NREM. It is unclear whether effective continuous positive airway pressure (CPAP) treatment reverses regional SWA deficits, and other regional sleep and wake EEG abnormalities, and whether any recovery relates to improved overnight memory consolidation.

Hippocampal Neuronal Integrity and Functional Connectivity Within the Default Mode Network in Mild Cognitive Impairment: A Multimodal Investigation.

In older people with mild cognitive impairment (MCI), the relationship between early changes in functional connectivity and changes in key neurometabolites is not known. Two established correlates of MCI diagnosis are decreased N-acetylaspartate (NAA) in the hippocampus, indicative of decreased neuronal integrity, and changes in the default mode network (DMN) functional network. If and how these measures interrelate is yet to be established, and such understanding may provide insight into the processes underpinning observed cognitive decline.

A Systematic Review of Quality Dementia Clinical Guidelines for the Development of WHO's Package of Interventions for Rehabilitation.

Background And Objectives: As part of the WHO Rehabilitation 2030 call for action, the WHO Rehabilitation Programme is developing its Package of Interventions for Rehabilitation (PIR) to support ministries of health around the globe in integrating rehabilitation services into health systems. As a vital step for this PIR development, we conducted a systematic review of clinical practice guidelines (CPGs) for dementia to identify interventions for rehabilitation and related evidence.

Research Design And Methods: Following WHO Rehabilitation Programme and Cochrane Rehabilitation's methodology, quality CPGs published in English between January 2010 and March 2020 were identified using PubMed, Embase, CINAHL, PEDro, Google Scholar, guideline databases, and professional society websites.

Brain oxidative stress and cognitive function in older adults with diabetes and pre-diabetes who are at risk for dementia.

Aims: Diabetes is an established risk factor for dementia. This study aimed to examine the relationship between various cognitive domains, brain oxidative stress and markers of diabetes in older adults at risk for dementia.

Methods: Older adults at risk for dementia underwent comprehensive neuropsychological and medical assessment.

Thalamic abnormalities in older adults with remitted early-onset depression using structural magnetic resonance imaging.

Background: The thalamus is a key diencephalic structure involved in major depressive disorder (MDD). Studies have consistently revealed abnormalities in thalamic volumes in older adults with late-onset depression (LOD), however abnormalities in older adults with early-onset depression (EOD) have not yet been well-studied.

Methods: Fifty-nine euthymic participants with a history of EOD and fifty-nine matched comparison participants without a lifetime history of depression underwent neuroimaging, medical and neuropsychological assessments.

Safety of higher doses of melatonin in adults: A systematic review and meta-analysis.

Melatonin is commonly used for sleep and jetlag at low doses. However, there is less documentation on the safety of higher doses, which are being increasingly used for a wide variety of conditions, including more recently COVID-19 prevention and treatment. The aim of this review was to investigate the safety of higher doses of melatonin in adults.

Engagement in cognitively stimulating activities in individuals with Mild Cognitive Impairment: relationships with neuropsychological domains and hippocampal volume.

Late-life participation in cognitively stimulating activities is thought to contribute to an individual's cognitive reserve and thus protect against cognitive decline, yet its association with clinical markers of neurodegeneration is not well established. To investigate, we developed a 13-item self-report "cognitively stimulating activities" questionnaire (CSA-Q), which was completed by a community sample of 269 older adults (>50 years) at risk of dementia. Participants met criteria for Mild Cognitive Impairment (MCI) and were classified as amnestic (aMCI; = 93) or non-amnestic (naMCI; = 176).

Poorer Theory of Mind in Amnestic Mild Cognitive Impairment Is Associated with Decreased Functional Connectivity in the Default Mode Network.

Background: Older adults living with amnestic mild cognitive impairment (aMCI) not only demonstrate impairments in Theory of Mind (ToM), relative to adults with non-amnestic MCI (naMCI), but are also at a higher risk of developing dementia.

Objective: Our primary objective was to ascertain whether default mode network (DMN) functional connectivity was differentially associated with ToM abilities between MCI subgroups.

Methods: Using functional magnetic resonance imaging, we investigated alterations in resting-state functional connectivity within the brain's DMN in a sample of 43 older adults with aMCI (n = 19) and naMCI (n = 24), previously reported to demonstrate poorer ToM abilities.

Association between lifetime depression history, hippocampal volume and memory in non-amnestic mild cognitive impairment.

Hippocampal subfield volume loss in older adults with amnestic mild cognitive impairment (aMCI) and depression history are associated with amyloid beta and tau pathology, thereby increasing the risk for Alzheimer's disease (AD). However, no studies have exclusively examined distinct alterations in hippocampal subfields in non-amnestic MCI (naMCI) in relation to depression history. Here, we used both longitudinal and transverse hippocampal segmentation methods using the automated FreeSurfer software to examine whether a lifetime depression history is associated with differences in hippocampal head/body/tail (H/B/T) and key subfield volumes (CA1, subiculum, dentate gyrus) in older adults with naMCI.

Feasibility of 3-month melatonin supplementation for brain oxidative stress and sleep in mild cognitive impairment: protocol for a randomised, placebo-controlled study.

Introduction: Melatonin has multiple proposed therapeutic benefits including antioxidant properties, synchronisation of the circadian system and lowering of blood pressure. In this protocol, we outline a randomised controlled trial to assess the feasibility, acceptability and tolerability of higher dose (25 mg) melatonin to target brain oxidative stress and sleep disturbance in older adults with mild cognitive impairment (MCI).

Methods And Analysis: The study design is a randomised double-blind, placebo-controlled, parallel group trial.

Sleep-Dependent Memory in Older People With and Without MCI: The Relevance of Sleep Microarchitecture, OSA, Hippocampal Subfields, and Episodic Memory.

This study aimed to determine if, relative to cognitively healthy controls, sleep-dependent memory consolidation (SDMC) is diminished in mild cognitive impairment (MCI), a group at high risk of conversion to dementia. We also sought to determine whether SDMC is associated with sleep characteristics, daytime episodic memory, and hippocampal integrity. Participants with MCI (n = 43) and controls (n = 20) underwent clinical and neuropsychological profiling.

Obesity and Oxidative Stress in Older Adults At Risk for Dementia: A Magnetic Resonance Spectroscopy Study.

Objective: This study aimed to investigate the relationship between obesity and oxidative stress in older adults at risk for dementia. It also aimed to explore the influence of physical activity on the relationship between obesity and oxidative stress in this at risk cohort.

Methods: Older adults at risk for dementia underwent comprehensive medical, neuropsychological, and psychiatric assessment.

Rest-activity functioning is related to white matter microarchitecture and modifiable risk factors in older adults at-risk for dementia.

Study Objectives: Growing evidence demonstrates pronounced alterations in rest-activity functioning in older adults at-risk for dementia. White matter degeneration, poor cardiometabolic functioning, and depression have also been linked to a greater risk of decline; however, limited studies have examined the white matter in relation to rest-activity functioning in at-risk older adults.

Methods: We investigated associations between nonparametric actigraphy measures and white matter microarchitecture using whole-brain fixel-based analysis of diffusion-weighted imaging in older adults (aged 50 years or older) at-risk for cognitive decline and dementia.

Irregular sleep-wake patterns in older adults with current or remitted depression.

Background: Disturbed sleep and irregular sleep-wake patterns have been associated with poor outcomes in older adults. Sleep regularity however has not been studied in a sample with current or remitted major depression.

Methods: 138 participants (63.

Actigraphy-recorded sleep efficiency and hippocampal volume are related to visual and verbal rate of forgetting in older adults.

This study aimed to determine if older adults "at-risk" for dementia (those with MCI or SMC) exhibit accelerated long-term forgetting (ALF) and whether rate of forgetting (RoF) is associated with sleep efficiency, hippocampal volume and demographic/clinical features. Forty-nine "at-risk" participants and eighteen controls underwent examination. Memory was assessed using the Scene Memory Task (SMT) and WMS-III Logical Memory (LM) subtest.

Objective measurement of sleep in mild cognitive impairment: A systematic review and meta-analysis.

Older adults with mild cognitive impairment (MCI) are at-risk of developing dementia, particularly Alzheimer's disease. While some research suggests that alterations in sleep architecture may mediate cognitive decline, the nature and magnitude of changes to sleep macro- (sleep stages) and micro-architecture (electroencephalography (EEG) oscillations) in MCI is not yet clear. This study aimed to systematically review and meta-analyse case-control studies objectively measuring sleep in MCI.

Memory Performance Correlates of Hippocampal Subfield Volume in Mild Cognitive Impairment Subtype.

The increased understanding that neuropathology begins decades before symptom onset, has led to the conceptualization and widespread utilization of Mild Cognitive Impairment (MCI) as an important transitional state between healthy aging and dementia. Further subcategorization to MCI subtype has led to more distinct prognoses and it is widely considered that amnestic and non-amnestic MCI (aMCI, naMCI) likely have distinct pathophysiologies. Yet, accurately classification remains contentious.

Nocturnal Hypoxemia Is Associated with Altered Parahippocampal Functional Brain Connectivity in Older Adults at Risk for Dementia.

Background: Obstructive sleep apnea is associated with an increased risk of developing mild cognitive impairment and dementia. Intermittent nocturnal hypoxemia in obstructive sleep apnea is associated with brain changes in key regions that underpin memory.

Objective: To determine whether older adults with severe nocturnal hypoxemia would exhibit reduced functional connectivity within these regions, with associated deficits in memory.

Theory of Mind in Mild Cognitive Impairment - Relationship with Limbic Structures and Behavioural Change.

Objectives: Older adults presenting with mild cognitive impairment (MCI) have a higher risk of developing dementia and also demonstrate impairments in social cognition. This study sought to establish whether in people with MCI, poorer theory of mind (ToM) was associated with volumetric changes in the amygdala and hippocampus, as well as early changes in behaviour.

Methods: One hundred and fourteen people with MCI and fifty-two older adult controls completed the Reading the Mind in the Eyes Test (RMET), while close informants (e.

Arterial stiffness relates to executive dysfunction in later life.

Cardiovascular disease in older people is often linked with cognitive impairment, particularly in domains of executive function and processing speed. Our aims examined whether carotid-femoral pulse wave velocity (PWV) related to subtle changes of executive function and processing speed. Fifty-six individuals with subjective mood and/or cognitive concerns underwent PWV and neuropsychological assessments of processing speed (Trail Making Test Part A) and executive functioning (Delis Kaplan Executive Function System Stroop Task; Trail Making Test Part B, TMT-B).

Elucidating the glutamatergic processes underlying mismatch negativity deficits in early stage bipolar disorder and schizophrenia: A combined H-MRS and EEG study.

Impairments in mismatch negativity (MMN) in schizophrenia are well-established; these findings have been extended to show impairments at early illness stages and in bipolar disorder. A substantial literature supports MMN as an index of NMDA receptor output, however, few studies have conducted in vivo assessments to elucidate the neurochemical underpinnings of MMN. Sixty young (16-33 years) participants with bipolar disorder (n = 47) or schizophrenia (n = 13) underwent H-MRS and MMN assessment.

Structural brain correlates of obstructive sleep apnoea in older adults at risk for dementia.

This study aimed to investigate associations between obstructive sleep apnoea (OSA) and cortical thickness in older adults with subjective and objective cognitive difficulties, who are considered "at-risk" for dementia.83 middle-aged to older adults (51-88 years) underwent neuropsychological testing, polysomnography assessment of OSA and a structural magnetic resonance imaging brain scan. A principal components analysis was performed on OSA measures.