Verbal memory is linked to average oxygen saturation during sleep, not the apnea-hypopnea index nor novel hypoxic load variables.

Introduction: The apnea-hypopnea index (AHI) is the current diagnostic parameter for diagnosing and estimating the severity of obstructive sleep apnea (OSA). It is, however, poorly associated with the main clinical symptom of OSA, excessive daytime sleepiness, and with the often-seen cognitive decline among OSA patients. To better evaluate OSA severity, novel hypoxic load parameters have been introduced that consider the duration and depth of oxygen saturation drops associated with apneas or hypopneas.

Comparative study of machine learning methods for modeling associations between risk factors and future dementia cases.

A substantial portion of dementia risk can be attributed to modifiable risk factors that can be affected by lifestyle changes. Identifying the contributors to dementia risk could prove valuable. Recently, machine learning methods have been increasingly applied to healthcare data.

Pituitary dysfunction following mild traumatic brain injury in female athletes.

Objective: Pituitary dysfunction following mild traumatic brain injury can have serious physical and psychological consequences, making correct diagnosis and treatment essential. To the best of our knowledge, this study is the first to study the prevalence of pituitary dysfunction following mild traumatic brain injury in an all-female population following detailed endocrinological work-up after screening for pituitary dysfunction in female athletes.

Design: This is a retrospective cohort study.

Exposure factors associated with dementia among older adults in Iceland: the AGES-Reykjavik study.

The study aimed to assess whether factors related to cognitive performance were associated with the development of dementia. Additionally, the study aimed to establish whether cognitive performance at baseline or change in cognition between baseline and follow-up (five-year period) had a stronger association with whether an individual would fulfill a dementia criterion at follow-up. The data was collected from 2002 to 2011.

Screening for possible hypopituitarism following mild traumatic brain injury: The first all-female study. Who do we need to evaluate further?

Background: Studies on hypopituitarism (HP) following mild traumatic brain injury (mTBI) have focused on male populations although women may be more susceptible to the sequelae of mTBI. This is, to the best of our knowledge, the first all-female study screening for HP following mTBI.

Objective: Screening for possible HP in female athletes reporting a history of one or more mTBI.

The ambivalence toward neuropsychology in dementia research, diagnosis, and drug development: Myths and misconceptions.

Clinical assessment remains the gold standard for diagnosing dementia, monitoring progression, and conducting clinical research. Biomarkers hold promise for targeted therapeutic approaches, selection of participants in clinical trials, and direct physiological efficacy readouts. However, the anchoring of biomarker research to clinical symptomatology is often based on short and insensitive cognitive screening.

Lay Knowledge About Dementia in Iceland: Symptoms and Risk and Protective Factors.

No studies are available on the lay knowledge about dementia in Nordic countries. A survey was sent to 829 Icelanders aged 25 to 65 (61.2% female).

Cognition and brain health among older adults in Iceland: the AGES-Reykjavik study.

The paper aimed to compare how factors previously identified as predictive factors for cognitive decline and dementia related to cognitive performance on the one hand and brain health on the other. To that aim, multiple linear regression was applied to the AGES-Reykjavik study epidemiological data. Additionally, a regression analysis was performed for change in cognition over 5 years, using the same exposure factors.

Phenotypic Displays of Cholinergic Enzymes Associate With Markers of Inflammation, Neurofibrillary Tangles, and Neurodegeneration in Pre- and Early Symptomatic Dementia Subjects.

Background: Cholinergic drugs are the most commonly used drugs for the treatment of Alzheimer's disease (AD). Therefore, a better understanding of the cholinergic system and its relation to both AD-related biomarkers and cognitive functions is of high importance.

Objectives: To evaluate the relationships of cerebrospinal fluid (CSF) cholinergic enzymes with markers of amyloidosis, neurodegeneration, neurofibrillary tangles, inflammation and performance on verbal episodic memory in a memory clinic cohort.

Towards defining biomarkers to evaluate concussions using virtual reality and a moving platform (BioVRSea).

Current diagnosis of concussion relies on self-reported symptoms and medical records rather than objective biomarkers. This work uses a novel measurement setup called BioVRSea to quantify concussion status. The paradigm is based on brain and muscle signals (EEG, EMG), heart rate and center of pressure (CoP) measurements during a postural control task triggered by a moving platform and a virtual reality environment.

Creativity, leisure activities, social engagement and cognitive impairment: the AGES-Reykjavík study.

Background: Participation in leisure activities and extensive social network have been associated with lower risk of cognitive impairment (CI) and dementia.

Aims: We examined whether leisure activities (cognitive solitary, cognitive group, social, physical, or creative activities) and social involvement are associated with less incidence of CI or dementia.

Methods: Analyses were performed from data of 2933 cognitively intact individuals at baseline included in the AGES-REYKJAVIK study.

Objective Measures of Cognitive Performance in Sleep Disorder Research.

Neurocognitive tests offer objective and reliable assessment of patients' status and progress. However, there is no consensus on how to use neurocognitive assessment in sleep disorder research. An effective use of neurocognitive assessment must be based on standardized practices and have a firm theoretic basis.

European Clinical Neuropsychology: Role in Healthcare and Access to Neuropsychological Services.

This study analyzed aspects of the work of clinical neuropsychologists across Europe. There are no published comparisons between European countries regarding the nature of clinical neuropsychologists' work. Forty-one national psychological and neuropsychological societies were approached, of which 31 (76%) responded.

Cerebrospinal Fluid C18 Ceramide Associates with Markers of Alzheimer's Disease and Inflammation at the Pre- and Early Stages of Dementia.

Background: Understanding how dysregulation in lipid metabolism relates to the severity of Alzheimer's disease (AD) pathology might be critical in developing effective treatments.

Objective: To identify lipid species in cerebrospinal fluid (CSF) associated with signature AD pathology and to explore their relationships with measures reflecting AD-related processes (neurodegeneration, inflammation, deficits in verbal episodic memory) among subjects at the pre- and early symptomatic stages of dementia.

Methods: A total of 60 subjects that had been referred to an Icelandic memory clinic cohort were classified as having CSF AD (n = 34) or non-AD (n = 26) pathology profiles.

Body weight changes and longitudinal associations with cognitive decline among community-dwelling older adults.

Introduction: We aim to investigate the longitudinal associations between changes in body weight (BW) and declines in cognitive function and risk of mild cognitive impairment (MCI)/dementia among cognitively normal individuals 65 years or older.

Methods: Data from the Age Gene/Environment Susceptibility-Reykjavik Study (AGES-Reykjavik Study) including 2620 participants, were examined using multiple logistic regression models. Cognitive function included speed of processing (SP), executive function (EF), and memory function (MF).

Self-reported concussion history among Icelandic female athletes with and without a definition of concussion.

Objective: This study examined whether Icelandic female athletes in contact sports, based their self-reported concussion history on adequate medical definitions, by assessing self-reported concussion history with and without a definition of concussion. Another aim was to examine whether currently active athletes were more knowledgeable of concussions than retired athletes.

Methods: Participants (age = 26.

Association of glial and neuronal degeneration markers with Alzheimer's disease cerebrospinal fluid profile and cognitive functions.

Background: Neuroinflammation has gained increasing attention as a potential contributing factor in the onset and progression of Alzheimer's disease (AD). The objective of this study was to examine the association of selected cerebrospinal fluid (CSF) inflammatory and neuronal degeneration markers with signature CSF AD profile and cognitive functions among subjects at the symptomatic pre- and early dementia stages.

Methods: In this cross-sectional study, 52 subjects were selected from an Icelandic memory clinic cohort.

Lifestyle and 25-hydroxy-vitamin D among community-dwelling old adults with dementia, mild cognitive impairment, or normal cognitive function.

Background: Several studies have indicated that older adults with cognitive impairment have a poorer lifestyle than their healthy peers including lower 25-hydroxy-vitamin D levels (25OHD).

Aim: To investigate the associations between lifestyle and 25OHD depending on cognitive status among old adults.

Methods: Community-dwelling old adults (65-96 years) participated in this cross-sectional study based on the Age-Gene/Environment-Susceptibility-Reykjavik-Study.

Resistance to change: Role of relationship and communal coping for coronary heart disease patients and their partners in making lifestyle changes.

Background: Lifestyle behaviours are important risk factors for coronary heart disease (CHD) and, hence, motivation for lifestyle changes is suggested to be a key factor in the success of cardiac rehabilitation and secondary prevention programmes. The motivation for changing lifestyle among people with CHD may be influenced by those with whom they have long-term, intimate relationships.

Aims: This study explores the role of the relationship between people with CHD and those closest to them in making lifestyle changes.

Incidence of Brain Infarcts, Cognitive Change, and Risk of Dementia in the General Population: The AGES-Reykjavik Study (Age Gene/Environment Susceptibility-Reykjavik Study).

Background And Purpose: The differentiation of brain infarcts by region is important because their cause and clinical implications may differ. Information on the incidence of these lesions and association with cognition and dementia from longitudinal population studies is scarce. We investigated the incidence of infarcts in cortical, subcortical, cerebellar, and overall brain regions and how prevalent and incident infarcts associate with cognitive change and incident dementia.

GWAS for executive function and processing speed suggests involvement of the CADM2 gene.

To identify common variants contributing to normal variation in two specific domains of cognitive functioning, we conducted a genome-wide association study (GWAS) of executive functioning and information processing speed in non-demented older adults from the CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology) consortium. Neuropsychological testing was available for 5429-32,070 subjects of European ancestry aged 45 years or older, free of dementia and clinical stroke at the time of cognitive testing from 20 cohorts in the discovery phase. We analyzed performance on the Trail Making Test parts A and B, the Letter Digit Substitution Test (LDST), the Digit Symbol Substitution Task (DSST), semantic and phonemic fluency tests, and the Stroop Color and Word Test.

Genome-wide studies of verbal declarative memory in nondemented older people: the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium.

Background: Memory performance in older persons can reflect genetic influences on cognitive function and dementing processes. We aimed to identify genetic contributions to verbal declarative memory in a community setting.

Methods: We conducted genome-wide association studies for paragraph or word list delayed recall in 19 cohorts from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium, comprising 29,076 dementia- and stroke-free individuals of European descent, aged ≥45 years.

Co-Presence of Multimorbidity and Disability with Frailty: An Examination of Heterogeneity in the Frail Older Population.

Background: Frailty is often associated with multimorbidity and disability.

Objectives: We investigated heterogeneity in the frail older population by characterizing five subpopulations according to quantitative biological markers, multimorbidity and disability, and examined their association with mortality and nursing home admission.

Design: Observational study.