Cognitive reserve, cortisol, and Alzheimer's disease biomarkers: A memory clinic study.

INTRODUCTION: Cognitive reserve might mitigate the risk of Alzheimer's dementia among memory clinic patients. No study has examined the potential modifying role of stress on this relation. METHODS: We examined cross-sectional associations of the cognitive reserve index (CRI; education, occupational complexity, physical and leisure activities, and social health) with cognitive performance and AD-related biomarkers among 113 memory clinic patients. The longitudinal association between CRI and cognition over a 3-year follow-up was assessed. We examined whether associations were influenced by perceived stress and five measures of diurnal salivary cortisol. RESULTS: Higher CRI scores were associated with better cognition. Adjusting for cortisol measures reduced the beneficial association of CRI on cognition. A higher CRI score was associated with better working memory in individuals with higher (favorable) cortisol AM/PM ratio, but not among individuals with low cortisol AM/PM ratio. No association was found between CRI and AD-related biomarkers. DISCUSSION: Physiological stress reduces the neurocognitive benefits of cognitive reserve among memory clinic patients. HIGHLIGHTS: Physiological stress may reduce the neurocognitive benefits accrued from cognitively stimulating and enriching life experiences (cognitive reserve [CR]) in memory clinic patients. Cortisol awakening response modified the relation between CR and P-tau181, a marker of Alzheimer's disease (AD). Effective stress management techniques for AD and related dementia prevention are warranted.

The expectations and experiences of patients regarding the diagnostic workup at a specialized memory clinic: An interview study.

BACKGROUND: Because of the shift towards earlier diagnosis of dementia and/or Alzheimer's disease (AD), increasing numbers of individuals with subjective cognitive decline (SCD) and mild cognitive impairment (MCI) are seen in memory clinics. Yet, evidence indicates that there is room for improvement when it comes to tailoring of the diagnostic work-up to the needs of individual patients. To optimize the quality of care, we explored patients' perspectives regarding the diagnostic work-up at a specialized memory clinic. METHODS: This interview study was conducted at Karolinska University Hospital (Sweden). The comprehensive diagnostic work-up for dementia at the memory clinic in Solna is conducted within 1 week. A sample of 15 patients (8 female; mean age = 61 years [range 50-72]; 11 SCD, 1 MCI and 3 AD dementia) was purposively selected for a series of three semistructured interviews, focussing on (1) needs and expectations (during the week of diagnostic testing), (2) experiences (within 2 weeks after test-result disclosure) and (3) reflections and evaluation (3 months after disclosure). Transcribed audio-recorded data were analyzed using thematic content analysis (using MaxQDA software). RESULTS: Three key themes were identified: (1) the expectations and motivations of individuals for visiting the memory clinic strongly impacted their experience; (2) the diagnostic work-up impacted individuals psychosocially and (3) the diagnostic work-up provided an opportunity to motivate individuals to adopt a healthier lifestyle. CONCLUSION: Our findings underscore the importance of enquiring about the expectations and needs of individuals referred to a specialized memory clinic, allowing for expectation management and personalization of provided information/advice, and potentially informing the selection of patients in need of a comprehensive diagnostic work-up. Structural guidance might be needed to support those with SCD and MCI to help them cope with uncertainty, potentially resolve their issues, and/or stimulate brain health. PATIENT OR PUBLIC CONTRIBUTION: We gathered the perspectives of 15 individuals who had been referred to the memory clinic at three different time points through semistructured interviews, and these interviews were the primary data source.

Diurnal cortisol, neuroinflammation, and neuroimaging visual rating scales in memory clinic patients.

BACKGROUND: Neuroinflammation is a hallmark of the Alzheimer's disease (AD) pathogenic process. Cortisol dysregulation may increase AD risk and is related to brain atrophy. This cross-sectional study aims to examine interactions of cortisol patterns and neuroinflammation markers in their association with neuroimaging correlates. METHOD: 134 participants were recruited from the Karolinska University Hospital memory clinic (Stockholm, Sweden). Four visual rating scales were applied to magnetic resonance imaging or computed tomography scans: medial temporal lobe atrophy (MTA), global cortical atrophy (GCA), white matter lesions (WML), and posterior atrophy. Participants provided saliva samples for assessment of diurnal cortisol patterns, and underwent lumbar punctures for cerebrospinal fluid (CSF) sampling. Three cortisol measures were used: the cortisol awakening response, total daily output, and the ratio of awakening to bedtime levels. Nineteen CSF neuroinflammation markers were categorized into five composite scores: proinflammatory cytokines, other cytokines, angiogenesis markers, vascular injury markers, and glial activation markers. Ordinal logistic regressions were conducted to assess associations between cortisol patterns, neuroinflammation scores, and visual rating scales, and interactions between cortisol patterns and neuroinflammation scores in relation to visual rating scales. RESULT: Higher levels of angiogenesis markers were associated with more severe WML. Some evidence was found for interactions between dysregulated diurnal cortisol patterns and greater neuroinflammation-related biomarkers in relation to more severe GCA and WML. No associations were found between cortisol patterns and visual rating scales. CONCLUSION: This study suggests an interplay between diurnal cortisol patterns and neuroinflammation in relation to brain structure. While this cross-sectional study does not provide information on causality or temporality, these findings suggest that neuroinflammation may be involved in the relationship between HPA-axis functioning and AD.

A multimodal precision-prevention approach combining lifestyle intervention with metformin repurposing to prevent cognitive impairment and disability: the MET-FINGER randomised controlled trial protocol.

BACKGROUND: Combining multimodal lifestyle interventions and disease-modifying drugs (novel or repurposed) could provide novel precision approaches to prevent cognitive impairment. Metformin is a promising candidate in view of the well-established link between type 2 diabetes (T2D) and Alzheimer's Disease and emerging evidence of its potential neuro-protective effects (e.g. vascular, metabolic, anti-senescence). MET-FINGER aims to test a FINGER 2.0 multimodal intervention, combining an updated FINGER multidomain lifestyle intervention with metformin, where appropriate, in an APOE ε4-enriched population of older adults (60-79 years) at increased risk of dementia. METHODS: MET-FINGER is an international randomised, controlled, parallel-group, phase-IIb proof-of-concept clinical trial, where metformin is included through a trial-within-trial design. 600 participants will be recruited at three sites (UK, Finland, Sweden). Participants at increased risk of dementia based on vascular risk factors and cognitive screening, will be first randomised to the FINGER 2.0 intervention (lifestyle + metformin if eligible; active arm) or to receive regular health advice (control arm). Participants allocated to the FINGER 2.0 intervention group at risk indicators of T2D will be additionally randomised to receive metformin (2000 mg/day or 1000 mg/day) or placebo. The study duration is 2 years. The changes in global cognition (primary outcome, using a Neuropsychological Test Battery), memory, executive function, and processing speed cognitive domains; functional status; lifestyle, vascular, metabolic, and other dementia-related risk factors (secondary outcomes), will be compared between the FINGER 2.0 intervention and the control arm. The feasibility, potential interaction (between-groups differences in healthy lifestyle changes), and disease-modifying effects of the lifestyle-metformin combination will be exploratory outcomes. The lifestyle intervention is adapted from the original FINGER trial (diet, physical activity, cognitive training, monitoring of cardiovascular/metabolic risk factors, social interaction) to be consistently delivered in three countries. Metformin is administered as Glucophage®XR/SR 500, (500 mg oral tablets). The metformin/placebo treatment will be double blinded. CONCLUSION: MET-FINGER is the first trial combining a multimodal lifestyle intervention with a putative repurposed disease-modifying drug for cognitive impairment prevention. Although preliminary, its findings will provide crucial information for innovative precision prevention strategies and form the basis for a larger phase-III trial design and future research in this field. TRIAL REGISTRATION: ClinicalTrials.gov (NCT05109169).

Life-course stress, cognition, and diurnal cortisol in memory clinic patients without dementia.

AIMS: To examine associations of life-course stress with cognition and diurnal cortisol patterns in older adulthood, as well as potential mediation effects of diurnal cortisol patterns and perceived stress on the association between life-course stress and cognition. METHODS: 127 participants without dementia were selected from a cohort of Swedish memory clinic patients. Cross-sectional associations between scores on two chronic stress questionnaires (perceived stress, stressful life events (SLEs)), five cognitive domains (overall cognition, memory, working memory, processing speed, perceptual reasoning), and two measures of diurnal cortisol patterns (total daily output, diurnal cortisol slope), as well as potential mediation effects of diurnal cortisol patterns and perceived stress on associations between life-course stress and cognition, were assessed using linear regressions. RESULTS: Greater lifetime exposure to SLEs was associated with worse memory, working memory, and processing speed performance, but not with diurnal cortisol patterns. A greater number of SLEs in late childhood was associated with worse working memory and processing speed, while a greater number of SLEs in non-recent adulthood were associated with better overall cognition and perceptual reasoning. Greater perceived stress was associated with a flattened diurnal cortisol slope, but not with cognition. No evidence for interplay between self-reported and physiological stress markers was found in relation to cognition, although there appeared to be a significant positive indirect association between economic/legal SLEs and the diurnal cortisol slope via perceived stress. CONCLUSIONS: The associations between SLEs and cognition depend on the period during which SLEs occur, but seem independent of late-life cortisol dysregulation.

Family Members' Experiences of Young-Onset Dementia: Becoming Responsible Yet Feeling Powerless.

Purpose: Dementia is often associated with old age but can also occur in midlife. The latter is commonly referred to as young-onset dementia (YOD). The diagnosis not only has an impact on the persons with YOD but also on their family members. For family members, the diagnosis changes their lives, as responsibilities and roles alter when the care and wellbeing of the relative increasingly come into focus. The aim of this study was to explore family members' experiences of sharing lives with a relative diagnosed with YOD - from onset of symptoms until the person relocated to a nursing home. Patients and Methods: The study has a qualitative approach with in-depth interviews. In total, the study included 15 family members aged ≥18 years participated, all with a relative diagnosed with dementia before the age of 65. At the time of the interview, all had a relative living in a nursing home. The interviews were analyzed using thematic analysis. Results: Two key themes were identified: Becoming responsible and Dealing with the situation. Family members found themselves increasingly responsible for many parts of their relatives' lives and forced to make decisions on their behalf. This was experienced as being lonely, as family members wished to share their responsibility. Despite of their efforts to control and deal with their situation, family members reported a lack of power to influence certain factors, such as access to appropriate healthcare services, causing feelings of distress. Conclusion: These findings emphasize the need of improved and tailored support and guidance for family members of persons with YOD. Further, the findings highlight the importance of increased knowledge and awareness among social workers and other healthcare professionals regarding support to family members of persons with YOD.

Transitions: Experiences of younger persons recently diagnosed with Alzheimer-type dementia.

Receiving a diagnosis of dementia before the age of 65 has a huge impact on everyday life. Previously, the disease trajectory has mainly been described from the perspective of older persons. However, young persons with dementia are confronted with specific challenges, influencing the type of life-changing events, or 'critical points' that they may experience. The aim of this study was therefore to describe experiences of persons recently being diagnosed with young-onset dementia. In total, 14 participants with dementia due to Alzheimer's disease (10 woman/4 men) with an average age of 59 were included in the study. Interviews were conducted within 2 months after receiving the diagnosis and analyzed using qualitative content analysis with an inductive approach, resulting in three categories: (1) A life changing moment, (2) An ongoing process, and (3) Remaining in control. The findings show that receiving such a diagnosis was experienced by participants as a life changing moment, followed by them seeking to come to terms with the diagnosis and reflecting on its meaning, in which various strategies were adopted to remain in control. The current study highlights three critical points considering the diagnosis of young-onset dementia that warrant special attention and provides insight into factors related to delay in healthy transitioning after receiving the diagnosis, as well as factors that may facilitate successful transitions.

Longitudinal study of Alzheimer's disease biomarkers, allostatic load, and cognition among memory clinic patients.

Background: Allostatic load (AL) is defined as the cumulative dysregulation of neuroendocrine, immunological, metabolic, and cardiovascular systems that increases the susceptibility to stress-related health problems. Several dementia and Alzheimer's disease (AD) risk factors have been identified, yet little is known about the role of AL and its associations with AD biomarkers (e.g., beta-amyloid (Aß) or tau) and cognitive function among memory clinic patients. Hence, this study aims to assess the association between AL and AD biomarkers, cognitive performance, and cognitive decline after 3-years of follow-up. Methods: Data from 188 memory clinic patients were derived from the Cortisol and Stress in AD (Co-STAR) study in Sweden. Participants underwent baseline assessments including blood tests for AL measures (including cortisol, thyroid stimulating hormone, cobalamin, homocysteine, leukocytes, glycated hemoglobin, albumin, high-density and low-density lipoprotein cholesterol, triglycerides, and creatinine), cerebrospinal fluid (CSF) sampling for AD biomarkers and neuropsychological tests including five cognitive domains. Linear regressions were conducted, adjusting for age, sex, and education. Results: Higher AL was associated with lower CSF Aß1-42 levels (ß = -0.175, p = 0.025), reflecting higher brain levels of Aß1-42. Stratified analyses suggested a significant association among women but not men, although the AL-sex interaction was not statistically significant. AL was not significantly associated with T-tau level (ß = -0.030, p = 0.682) and P-tau level (ß = 0.091, p = 0.980). There were no significant associations between AL and cognition or cognitive decline after 3 years. Conclusion: This study showed that higher AL was associated with increased brain amyloid accumulation. This suggests that AL may play a role in AD/dementia pathophysiology. Potential sex-related differences should be assessed in further larger studies.

Cortisol, cognition and Alzheimer's disease biomarkers among memory clinic patients.

Objective: This study aims to investigate the relationship between diurnal cortisol patterns, cognition and Alzheimer's disease (AD) biomarkers in memory clinic patients. Method: Memory clinic patients were recruited from Karolinska University Hospital in Sweden (n=155). Diurnal cortisol patterns were assessed using five measures: awakening levels, cortisol awakening response, bedtime levels, the ratio of awakening to bedtime levels (AM/PM ratio) and total daily output. Cognition was measured in five domains: memory, working memory, processing speed, perceptual reasoning and overall cognition. AD biomarkers Aß42, total tau and phosphorylated tau were assessed from cerebrospinal fluid (CSF). Cognition was measured at follow-up (average 32 months) in a subsample of participants (n=57). Results: In assessing the associations between cortisol and cognition, higher awakening cortisol levels were associated with greater processing speed at baseline. No relationship was found between diurnal cortisol patterns and change in cognition over time or CSF AD biomarkers in the total sample. After stratification by CSF Aß42 levels, higher awakening cortisol levels were associated with worse memory performance in amyloid-positive participants. In amyloid-negative participants, higher bedtime cortisol levels and a lower AM/PM ratio were associated with lower overall cognition, greater awakening cortisol levels were associated with better processing speed, and a higher AM/PM ratio was associated with better perceptual reasoning. Additionally, higher awakening cortisol levels were associated with lower CSF Aß42 levels in amyloid-positive participants, while higher bedtime cortisol levels and a lower AM/PM ratio were associated with higher CSF total tau in amyloid-negative participants. Conclusions: Our findings suggest that diurnal cortisol patterns are associated with cognitive function and provide new insights into the association between diurnal cortisol patterns and AD-related CSF biomarkers. Further research is needed to examine the complex relationship between cortisol, cognition and brain pathology.

The Karolinska NeuroCOVID study protocol: Neurocognitive impairment, biomarkers and advanced imaging in critical care survivors.

BACKGROUND: This is the study plan of the Karolinska NeuroCOVID study, a study of neurocognitive impairment after severe COVID-19, relating post-intensive care unit (ICU) cognitive and neurological deficits to biofluid markers and MRI. The COVID-19 pandemic has posed enormous health challenges to individuals and health-care systems worldwide. An emerging feature of severe COVID-19 is that of temporary and extended neurocognitive impairment, exhibiting a myriad of symptoms and signs. The causes of this symptomatology have not yet been fully elucidated. METHODS: In this study, we aim to investigate patients treated for severe COVID-19 in the ICU, as to describe and relate serum-, plasma- and cerebrospinal fluid-borne molecular and cellular biomarkers of immune activity, coagulopathy, cerebral damage, neuronal inflammation, and degeneration, to the temporal development of structural and functional changes within the brain as evident by serial MRI and extensive cognitive assessments at 3-12 months after ICU discharge. RESULTS: To date, we have performed 51 3-month follow-up MRIs in the ICU survivors. Of these, two patients (~4%) have had incidental findings on brain MRI findings requiring activation of the Incidental Findings Management Plan. Furthermore, the neuropsychological and neurological examinations have so far revealed varying and mixed patterns. Several patients expressed cognitive and/or mental concerns and fatigue, complaints closely related to brain fog. CONCLUSION: The study goal is to gain a better understanding of the pathological mechanisms and neurological consequences of this new disease, with a special emphasis on neurodegenerative and neuroinflammatory processes, in order to identify targets of intervention and rehabilitation.