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Casanova F, Tian Q, Atkins JL, Wood AR, Williamson D, Qian Y, Zweibaum D, Ding J, Melzer D, Ferrucci L, Pilling LC. Iron and risk of dementia: Mendelian randomisation analysis in UK Biobank. J Med Genet 2024; 61:435-442. [PMID: 38191510 DOI: 10.1136/jmg-2023-109295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 11/28/2023] [Indexed: 01/10/2024]
Abstract
BACKGROUND Brain iron deposition is common in dementia, but whether serum iron is a causal risk factor is unknown. We aimed to determine whether genetic predisposition to higher serum iron status biomarkers increased risk of dementia and atrophy of grey matter. METHODS We analysed UK Biobank participants clustered into European (N=451284), African (N=7477) and South Asian (N=9570) groups by genetic similarity to the 1000 genomes project. Using Mendelian randomisation methods, we estimated the association between genetically predicted serum iron (transferrin saturation [TSAT] and ferritin), grey matter volume and genetic liability to clinically defined dementia (including Alzheimer's disease [AD], non-AD dementia, and vascular dementia) from hospital and primary care records. We also performed time-to-event (competing risks) analysis of the TSAT polygenic score on risk of clinically defined non-AD dementia. RESULTS In Europeans, higher genetically predicted TSAT increased genetic liability to dementia (Odds Ratio [OR]: 1.15, 95% Confidence Intervals [CI] 1.04 to 1.26, p=0.0051), non-AD dementia (OR: 1.27, 95% CI 1.12 to 1.45, p=0.00018) and vascular dementia (OR: 1.37, 95% CI 1.12 to 1.69, p=0.0023), but not AD (OR: 1.00, 95% CI 0.86 to 1.15, p=0.97). Higher TSAT was also associated with increased risk of non-AD dementia in participants of African, but not South Asian groups. In survival analysis using a TSAT polygenic score, the effect was independent of apolipoprotein-E ε4 genotype (with adjustment subdistribution Hazard Ratio: 1.74, 95% CI 1.33 to 2.28, p=0.00006). Genetically predicted TSAT was associated with lower grey matter volume in caudate, putamen and thalamus, and not in other areas of interest. DISCUSSION Genetic evidence supports a causal relationship between higher TSAT and risk of clinically defined non-AD and vascular dementia, in European and African groups. This association appears to be independent of apolipoprotein-E ε4.
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Affiliation(s)
- Francesco Casanova
- Department of Clinical and Biomedical Sciences, University of Exeter, Exeter, UK
| | - Qu Tian
- Translational Gerontology Branch Longitudinal Studies Section, National Institute on Aging, Bethesda, Maryland, USA
| | - Janice L Atkins
- Department of Clinical and Biomedical Sciences, University of Exeter, Exeter, UK
| | - Andrew R Wood
- Department of Clinical and Biomedical Sciences, University of Exeter, Exeter, UK
| | | | - Yong Qian
- Translational Gerontology Branch Longitudinal Studies Section, National Institute on Aging, Bethesda, Maryland, USA
| | - David Zweibaum
- Translational Gerontology Branch Longitudinal Studies Section, National Institute on Aging, Bethesda, Maryland, USA
| | - Jun Ding
- Translational Gerontology Branch Longitudinal Studies Section, National Institute on Aging, Bethesda, Maryland, USA
| | - David Melzer
- Department of Clinical and Biomedical Sciences, University of Exeter, Exeter, UK
| | - Luigi Ferrucci
- Translational Gerontology Branch Longitudinal Studies Section, National Institute on Aging, Bethesda, Maryland, USA
| | - Luke C Pilling
- Department of Clinical and Biomedical Sciences, University of Exeter, Exeter, UK
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Lee EY, Kim J, Prado-Rico JM, Du G, Lewis MM, Kong L, Yanosky JD, Eslinger P, Kim BG, Hong YS, Mailman RB, Huang X. Effects of mixed metal exposures on MRI diffusion features in the medial temporal lobe. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2023.07.18.23292828. [PMID: 37503124 PMCID: PMC10371112 DOI: 10.1101/2023.07.18.23292828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Background Environmental exposure to metal mixtures is common and may be associated with increased risk for neurodegenerative disorders including Alzheimer's disease. Objective This study examined associations of mixed metal exposures with medial temporal lobe (MTL) MRI structural metrics and neuropsychological performance. Methods Metal exposure history, whole blood metal, and neuropsychological tests were obtained from subjects with/without a history of mixed metal exposure from welding fumes (42 exposed subjects; 31 controls). MTL structures (hippocampus, entorhinal and parahippocampal cortices) were assessed by morphologic (volume, cortical thickness) and diffusion tensor imaging [mean (MD), axial (AD), radial diffusivity (RD), and fractional anisotropy (FA)] metrics. In exposed subjects, correlation, multiple linear, Bayesian kernel machine regression, and mediation analyses were employed to examine effects of single- or mixed-metal predictor(s) and their interactions on MTL structural and neuropsychological metrics; and on the path from metal exposure to neuropsychological consequences. Results Compared to controls, exposed subjects had higher blood Cu, Fe, K, Mn, Pb, Se, and Zn levels (p's<0.026) and poorer performance in processing/psychomotor speed, executive, and visuospatial domains (p's<0.046). Exposed subjects displayed higher MD, AD, and RD in all MTL ROIs (p's<0.040) and lower FA in entorhinal and parahippocampal cortices (p's<0.033), but not morphological differences. Long-term mixed-metal exposure history indirectly predicted lower processing speed performance via lower parahippocampal FA (p=0.023). Higher whole blood Mn and Cu predicted higher entorhinal diffusivity (p's<0.043) and lower Delayed Story Recall performance (p=0.007) without overall metal mixture or interaction effects. Discussion Mixed metal exposure predicted MTL structural and neuropsychological features that are similar to Alzheimer's disease at-risk populations. These data warrant follow-up as they may illuminate the path for environmental exposure to Alzheimer's disease-related health outcomes.
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Affiliation(s)
- Eun-Young Lee
- Department of Health Care and Science, Dong-A University, Busan, South-Korea
| | - Juhee Kim
- Department of Health Care and Science, Dong-A University, Busan, South-Korea
| | - Janina Manzieri Prado-Rico
- Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
| | - Guangwei Du
- Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
| | - Mechelle M. Lewis
- Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
- Department of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
| | - Lan Kong
- Department of Public Health Sciences, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
| | - Jeff D. Yanosky
- Department of Public Health Sciences, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
| | - Paul Eslinger
- Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
| | - Byoung-Gwon Kim
- Department of Preventive Medicine, College of Medicine, Dong-A University, Busan, South Korea
| | - Young-Seoub Hong
- Department of Preventive Medicine, College of Medicine, Dong-A University, Busan, South Korea
| | - Richard B. Mailman
- Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
- Department of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
| | - Xuemei Huang
- Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
- Department of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
- Department of Radiology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
- Department of Neurosurgery, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
- Department of Kinesiology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
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Lee SY, Paolillo EW, Saloner R, Cobigo Y, Diaz VE, Gontrum EQ, VandeBunte A, Chatterjee A, Tucker M, Kramer JH, Casaletto KB. Moderating role of physical activity on hippocampal iron deposition and memory outcomes in typically aging older adults. Neurobiol Aging 2023; 131:124-131. [PMID: 37633118 DOI: 10.1016/j.neurobiolaging.2023.07.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 06/23/2023] [Accepted: 07/26/2023] [Indexed: 08/28/2023]
Abstract
Physical activity (PA) is linked to better cognitive and brain health, though its mechanisms are unknown. While brain iron is essential for normal function, levels increase with age and, when excessive, can cause detrimental neural effects. We examined how objectively measured PA relates to cerebral iron deposition and memory functioning in normal older adults. Sixty-eight cognitively unimpaired older adults from the UCSF Memory and Aging Center completed neuropsychological testing and brain magnetic resonance imaging, followed by 30-day Fitbit monitoring. Magnetic resonance imaging quantitative susceptibility mapping (QSM) quantified iron deposition. PA was operationalized as average daily steps. Linear regression models examined memory as a function of hippocampal QSM, PA, and their interaction. Higher bilateral hippocampal iron deposition correlated with worse memory but was not strongly related to PA. Covarying for demographics, PA moderated the relationship between bilateral hippocampal iron deposition and memory such that the negative effect of hippocampal QSM on memory performances was no longer significant above 9120 daily steps. PA may mitigate adverse iron-related pathways for memory health.
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Affiliation(s)
- Shannon Y Lee
- Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Emily W Paolillo
- Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Rowan Saloner
- Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Yann Cobigo
- Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Valentina E Diaz
- Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Eva Q Gontrum
- Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Anna VandeBunte
- Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Ankita Chatterjee
- Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Miwa Tucker
- Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Joel H Kramer
- Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Kaitlin B Casaletto
- Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA, USA.
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Maynard-Smith L, Derrick JP, Borrow R, Lucidarme J, Maiden MCJ, Heyderman RS, Harrison OB. Genome-Wide Association Studies Identify an Association of Transferrin Binding Protein B Variation and Invasive Serogroup Y Meningococcal Disease in Older Adults. J Infect Dis 2022; 226:2204-2214. [PMID: 36322504 PMCID: PMC9748998 DOI: 10.1093/infdis/jiac430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 10/24/2022] [Accepted: 10/31/2022] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Neisseria meningitidis serogroup Y, especially ST-23 clonal complex (Y:cc23), represents a larger proportion of invasive meningococcal disease (IMD) in older adults compared to younger individuals. This study explored the meningococcal genetic variation underlying this association. METHODS Maximum-likelihood phylogenies and the pangenome were analyzed using whole-genome sequence (WGS) data from 200 Y:cc23 isolates in the Neisseria PubMLST database. Genome-wide association studies (GWAS) were performed on WGS data from 250 Y:cc23 isolates from individuals with IMD aged ≥65 years versus < 65 years. RESULTS Y:cc23 meningococcal variants did not cluster by age group or disease phenotype in phylogenetic analyses. Pangenome comparisons found no differences in presence or absence of genes in IMD isolates from the different age groups. GWAS identified differences in nucleotide polymorphisms within the transferrin-binding protein B (tbpB) gene in isolates from individuals ≥65 years of age. TbpB structure modelling suggests these may impact binding of human transferrin. CONCLUSIONS These data suggest differential iron scavenging capacity amongst Y:cc23 meningococci isolated from older compared to younger patients. Iron acquisition is essential for many bacterial pathogens including the meningococcus. These polymorphisms may facilitate colonization, thereby increasing the risk of disease in vulnerable older people with altered nasopharyngeal microbiomes and nutritional status.
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Affiliation(s)
- Laura Maynard-Smith
- Correspondence: Laura Maynard-Smith, MBBS, Division of Infection and Immunity, University College London, Gower Street, London WC1E 6BT, UK ()
| | - Jeremy P Derrick
- Faculty of Biology, Medicine, and Health, University of Manchester, Manchester, United Kingdom
| | - Ray Borrow
- Meningococcal Reference Unit, UK Health Security Agency, Manchester, United Kingdom
| | - Jay Lucidarme
- Meningococcal Reference Unit, UK Health Security Agency, Manchester, United Kingdom
| | | | - Robert S Heyderman
- Division of Infection and Immunity, University College London, London, United Kingdom
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Blood Analytes as Biomarkers of Mechanisms Involved in Alzheimer’s Disease Progression. Int J Mol Sci 2022; 23:ijms232113289. [DOI: 10.3390/ijms232113289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/25/2022] [Accepted: 10/29/2022] [Indexed: 11/06/2022] Open
Abstract
Alzheimer’s disease (AD) is the leading cause of dementia, but the pathogenetic factors are not yet well known, and the relationships between brain and systemic biochemical derangements and disease onset and progression are unclear. We aim to focus on blood biomarkers for an accurate prognosis of the disease. We used a dataset characterized by longitudinal findings collected over the past 10 years from 90 AD patients. The dataset included 277 observations (both clinical and biochemical ones, encompassing blood analytes encompassing routine profiles for different organs, together with immunoinflammatory and oxidative markers). Subjects were grouped into four severity classes according to the Clinical Dementia Rating (CDR) Scale: mild (CDR = 0.5 and CDR = 1), moderate (CDR = 2), severe (CDR = 3) and very severe (CDR = 4 and CDR = 5). Statistical models were used for the identification of potential blood markers of AD progression. Moreover, we employed the Pathfinder tool of the Reactome database to investigate the biological pathways in which the analytes of interest could be involved. Statistical results reveal an inverse significant relation between four analytes (high-density cholesterol, total cholesterol, iron and ferritin) with AD severity. In addition, the Reactome database suggests that such analytes could be involved in pathways that are altered in AD progression. Indeed, the identified blood markers include molecules that reflect the heterogeneous pathogenetic mechanisms of AD. The combination of such blood analytes might be an early indicator of AD progression and constitute useful therapeutic targets.
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Pan W, Chen H, Ni C, Zong G, Yuan C, Yang M. Sex-Specific Associations of Dietary Iron Intake with Brain Iron Deposition on Imaging and Incident Dementia: A Prospective Cohort Study. J Nutr Health Aging 2022; 26:954-961. [PMID: 36259584 DOI: 10.1007/s12603-022-1852-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
OBJECTIVES The study aimed to evaluate the association of dietary iron intake with incident dementia and brain iron deposition. DESIGN/SETTING/PARTICIPANTS We included dementia-free participants from the UK Biobank who completed at least one 24-hour dietary recall at study baseline (2009-2012) and were followed up to 2021. Incident dementia was determined through linkage to medical records and death registries. Brain MRI was conducted in a subgroup of participants since 2014, with T2* measurements being used as indicators of brain iron deposition. MEASUREMENTS Cox proportional hazard models were used to assess the associations of high (top quintile) and low (bottom quintile) versus medium (quintile 2 to 4) level of dietary iron intake with incident dementia, respectively. Linear regression was applied to assess the relations between dietary iron intake and brain T2* measurements. RESULTS During follow-up (mean = 9.5 years), a total of 1,454 participants (650 women and 804 men) developed dementia among 191,694 participants (55.0% female; mean age, 56.2 years). When adjusted for sociodemographic, lifestyle, and other dietary factors, participants with low dietary iron intake (< 10.05 mg/day) had a significantly higher dementia risk (hazard ratio [HR], 1.50, 95% confidence interval [CI], 1.19-1.89), while the relation for high intake (> 16.92 mg/day) was non-significant (HR, 1.16, 95% CI, 0.92-1.46). A significant gender difference (P-interaction < 0.001) was observed, with a U-shaped association in male participants (HR for low vs. medium, 1.56, 95% CI, 1.14-2.13; HR for high vs. medium, 1.39, 95% CI, 1.03 - 1.88; P-nonlinearity < 0.001) and no significant association in females, regardless of their menopause status. In general, dietary iron intake was not related to T2* measurements of iron deposition in most brain regions. CONCLUSION Our findings suggested a U-shape relationship between dietary iron intake and risk of dementia among males, but not females.
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Affiliation(s)
- W Pan
- Min Yang, School of Public Health, Zhejiang University School of Medicine, 866 Yu-hang-tang RD, Hangzhou, China, Tel: 13516852440, ; Changzheng Yuan, School of Public Health, Zhejiang University School of Medicine, 866 Yu-hang-tang RD, Hangzhou, China, Tel: 17326860291, E-mail:
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Gong Z, Song W, Gu M, Zhou X, Tian C. Association between serum iron concentrations and cognitive impairment in older adults aged 60 years and older: A dose-response analysis of National Health and Nutrition Examination Survey. PLoS One 2021; 16:e0255595. [PMID: 34339453 PMCID: PMC8328322 DOI: 10.1371/journal.pone.0255595] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 07/21/2021] [Indexed: 11/18/2022] Open
Abstract
Epidemiological evidence on peripheral iron and cognitive impairment in older adults is sparse and limited. Results on serum iron and cognitive impairment in older adults from the National Health and Nutrition Examination Survey have not been reported. Data on serum iron and cognitive impairment from individuals ≥ 60 years of age were obtained from the 2011–2014 NHANES (N = 3,131). Serum iron concentrations were determined with DcX800 method. Cognitive impairment was assessed with four cognitive tests: the Digit Symbol Substitution Test (DSST), the Animal Fluency (AF), the Consortium to Establish a Registry for Alzheimer’s Disease Delayed Recall (CERAD-DR) and Word Learning (CERAD-WL) tests. Logistic regression and restricted cubic splines were adopted to explore the dose-response relationship between serum iron concentrations and cognitive impairment. Comparing the highest to lowest tertile of serum iron concentrations, the multivariate-adjusted odds ratios of scoring low on the DSST were 0.70 (0.49–1.00), 0.88 (0.65–1.20) for CERAD-WL, 0.65 (0.48–0.88) for CERAD-DR, and 0.78 (0.53–1.15) for AF. Stratified analyses by sex showed that the above-mentioned associations were mainly found in men; however, the interaction with sex was not significant. Dose-response analysis showed that relationships between serum iron and cognitive impairment evaluated by DSST and CERAD-DR were linear, respectively.
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Affiliation(s)
- Zonglin Gong
- Department of Integrated Services, Kunshan Centers for Disease Control and Prevention, Kunshan, Jiangsu, China
| | - Wenlei Song
- Department of Integrated Services, Kunshan Centers for Disease Control and Prevention, Kunshan, Jiangsu, China
| | - Minjun Gu
- Department of Disease Control, Kunshan Centers for Disease Control and Prevention, Kunshan, Jiangsu, China
| | - Xiaoming Zhou
- Department of Integrated Services, Kunshan Centers for Disease Control and Prevention, Kunshan, Jiangsu, China
| | - Changwei Tian
- Department of Integrated Services, Kunshan Centers for Disease Control and Prevention, Kunshan, Jiangsu, China
- * E-mail:
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Maccora J, Peters R, Anstey KJ. What does (low) education mean in terms of dementia risk? A systematic review and meta-analysis highlighting inconsistency in measuring and operationalising education. SSM Popul Health 2020; 12:100654. [PMID: 33313373 PMCID: PMC7721642 DOI: 10.1016/j.ssmph.2020.100654] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 08/09/2020] [Accepted: 08/15/2020] [Indexed: 12/19/2022] Open
Abstract
Low education is considered an important modifiable risk factor for dementia worldwide, despite the lack of a formal consensus definition of low education. The primary aim of this systematic review was to document and address the inconsistency in measuring and operationalising education in dementia studies. A secondary aim was to consider the dose of education required to reduce dementia risk. The protocol was registered at PROSPERO with registration ID CRD42018096168. CINAHL, Cochrane, PsycInfo, and Pubmed databases were searched using terms related to education, dementia and/or MCI, and incidence. Studies were eligible for inclusion if a risk ratio for education and any dementia, Alzheimer's Disease (AD), Vascular Dementia (VaD) or Mild Cognitive Impairment (MCI) was reported in a population cognitively healthy at baseline. Sample sizes for 65 studies meeting selection criteria ranged from 152 to 12,881, representing populations from 24 countries. Risk of bias, assessed using a tool designed specifically for dementia risk studies, was found to be medium or low for all studies. There were 23 continuous, 29 dichotomous, and 31 categorical operationalisations of education reported. Random effects meta-analyses from continuous operationalisations suggested each year of education reduced risk by eight percent for AD (95% CI:5-12%) and seven percent for any dementia (95% CI:6-9%). Dichotomous operationalisations indicated an increased risk for low education of 45% (95% CI:29-63%) for any dementia and 85% (95% CI:56-118%) for AD, however definitions of low education were heterogeneous, ranging from zero to 12 years. There were too few studies to produce summary ratios for VaD or MCI. We conclude that, while the evidence of an association between low education and dementia incidence is robust, inconsistency in the definition, measurement and operationalisation of education hinders the translation of this evidence into practical policy recommendations to reduce dementia risk.
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Affiliation(s)
- Janet Maccora
- School of Psychology, University of New South Wales, Sydney, New South Wales, Australia
- Neuroscience Research Australia (NeuRA), Sydney, New South Wales, Australia
- Australian Research Council Centre of Excellence in Populating Ageing Research (CEPAR), Australia
| | - Ruth Peters
- School of Psychology, University of New South Wales, Sydney, New South Wales, Australia
- Neuroscience Research Australia (NeuRA), Sydney, New South Wales, Australia
- Australian Research Council Centre of Excellence in Populating Ageing Research (CEPAR), Australia
| | - Kaarin J. Anstey
- School of Psychology, University of New South Wales, Sydney, New South Wales, Australia
- Neuroscience Research Australia (NeuRA), Sydney, New South Wales, Australia
- Australian National University, Canberra, Australian Capital Territory, Australia
- Australian Research Council Centre of Excellence in Populating Ageing Research (CEPAR), Australia
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Portugal-Nunes C, Castanho TC, Amorim L, Moreira PS, Mariz J, Marques F, Sousa N, Santos NC, Palha JA. Iron Status is Associated with Mood, Cognition, and Functional Ability in Older Adults: A Cross-Sectional Study. Nutrients 2020; 12:E3594. [PMID: 33238615 PMCID: PMC7700455 DOI: 10.3390/nu12113594] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 11/02/2020] [Accepted: 11/19/2020] [Indexed: 01/04/2023] Open
Abstract
Several conditions are risk factors for iron deficiency (ID), some of which are highly prevalent in older individuals. Despite the amount of evidence pointing for a role of ID in cognition, mood and physical functional ability, the research addressing these associations in older individuals is still scarce. In the present study, 162 older community-dwelling individuals (29.53% classified as ID) were enrolled in a cross-sectional analysis and characterized regarding cognition, mood, functional ability, general nutritional intake and iron status. Assessment of iron status was performed using several blood biomarkers. Storage and erythropoiesis dimensions were positively associated with memory, along with an interaction (moderator effect) between iron storage and nutritional status. A more depressed mood was negatively associated with (iron) transport, transport saturation and erythropoiesis dimensions, and functional tiredness was positively associated with the erythropoiesis dimension. These observations indicate that lower iron status is associated with depressive mood, functional tiredness and poorer memory ability, with the latter moderated by nutritional status. These findings suggest that using iron as a continuous variable may be useful in finding associations with iron homeostasis, eventually missed when iron levels are considered within the usual classification groups.
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Affiliation(s)
- Carlos Portugal-Nunes
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; (C.P.-N.); (T.C.C.); (L.A.); (P.S.M.); (J.M.); (F.M.); (N.S.); (N.C.S.)
- ICVS/3B′s, PT Government Associate Laboratory, 4710-057 Braga/Guimarães, Portugal
- Clinical Academic Center—Braga, 4710-243 Braga, Portugal
| | - Teresa Costa Castanho
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; (C.P.-N.); (T.C.C.); (L.A.); (P.S.M.); (J.M.); (F.M.); (N.S.); (N.C.S.)
- ICVS/3B′s, PT Government Associate Laboratory, 4710-057 Braga/Guimarães, Portugal
- Clinical Academic Center—Braga, 4710-243 Braga, Portugal
| | - Liliana Amorim
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; (C.P.-N.); (T.C.C.); (L.A.); (P.S.M.); (J.M.); (F.M.); (N.S.); (N.C.S.)
- ICVS/3B′s, PT Government Associate Laboratory, 4710-057 Braga/Guimarães, Portugal
- Associação Centro de Medicina P5 (ACMP5), 4710-057 Braga, Portugal
| | - Pedro Silva Moreira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; (C.P.-N.); (T.C.C.); (L.A.); (P.S.M.); (J.M.); (F.M.); (N.S.); (N.C.S.)
- ICVS/3B′s, PT Government Associate Laboratory, 4710-057 Braga/Guimarães, Portugal
- Clinical Academic Center—Braga, 4710-243 Braga, Portugal
| | - José Mariz
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; (C.P.-N.); (T.C.C.); (L.A.); (P.S.M.); (J.M.); (F.M.); (N.S.); (N.C.S.)
- ICVS/3B′s, PT Government Associate Laboratory, 4710-057 Braga/Guimarães, Portugal
- Clinical Academic Center—Braga, 4710-243 Braga, Portugal
- Emergency Department, Intermediate Care Unit (EDIMCU), Hospital de Braga, 4710-243 Braga, Portugal
| | - Fernanda Marques
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; (C.P.-N.); (T.C.C.); (L.A.); (P.S.M.); (J.M.); (F.M.); (N.S.); (N.C.S.)
- ICVS/3B′s, PT Government Associate Laboratory, 4710-057 Braga/Guimarães, Portugal
| | - Nuno Sousa
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; (C.P.-N.); (T.C.C.); (L.A.); (P.S.M.); (J.M.); (F.M.); (N.S.); (N.C.S.)
- ICVS/3B′s, PT Government Associate Laboratory, 4710-057 Braga/Guimarães, Portugal
- Clinical Academic Center—Braga, 4710-243 Braga, Portugal
| | - Nadine Correia Santos
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; (C.P.-N.); (T.C.C.); (L.A.); (P.S.M.); (J.M.); (F.M.); (N.S.); (N.C.S.)
- ICVS/3B′s, PT Government Associate Laboratory, 4710-057 Braga/Guimarães, Portugal
- Associação Centro de Medicina P5 (ACMP5), 4710-057 Braga, Portugal
| | - Joana Almeida Palha
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; (C.P.-N.); (T.C.C.); (L.A.); (P.S.M.); (J.M.); (F.M.); (N.S.); (N.C.S.)
- ICVS/3B′s, PT Government Associate Laboratory, 4710-057 Braga/Guimarães, Portugal
- Clinical Academic Center—Braga, 4710-243 Braga, Portugal
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10
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Grubić Kezele T, Ćurko-Cofek B. Age-Related Changes and Sex-Related Differences in Brain Iron Metabolism. Nutrients 2020; 12:E2601. [PMID: 32867052 PMCID: PMC7551829 DOI: 10.3390/nu12092601] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 08/24/2020] [Accepted: 08/25/2020] [Indexed: 12/21/2022] Open
Abstract
Iron is an essential element that participates in numerous cellular processes. Any disruption of iron homeostasis leads to either iron deficiency or iron overload, which can be detrimental for humans' health, especially in elderly. Each of these changes contributes to the faster development of many neurological disorders or stimulates progression of already present diseases. Age-related cellular and molecular alterations in iron metabolism can also lead to iron dyshomeostasis and deposition. Iron deposits can contribute to the development of inflammation, abnormal protein aggregation, and degeneration in the central nervous system (CNS), leading to the progressive decline in cognitive processes, contributing to pathophysiology of stroke and dysfunctions of body metabolism. Besides, since iron plays an important role in both neuroprotection and neurodegeneration, dietary iron homeostasis should be considered with caution. Recently, there has been increased interest in sex-related differences in iron metabolism and iron homeostasis. These differences have not yet been fully elucidated. In this review we will discuss the latest discoveries in iron metabolism, age-related changes, along with the sex differences in iron content in serum and brain, within the healthy aging population and in neurological disorders such as multiple sclerosis, Parkinson's disease, Alzheimer's disease, and stroke.
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Affiliation(s)
- Tanja Grubić Kezele
- Department of Physiology and Immunology, Faculty of Medicine, University of Rijeka, Braće Branchetta 20, 51000 Rijeka, Croatia;
- Clinical Department for Clinical Microbiology, Clinical Hospital Center Rijeka, Krešimirova 42, 51000 Rijeka, Croatia
| | - Božena Ćurko-Cofek
- Department of Physiology and Immunology, Faculty of Medicine, University of Rijeka, Braće Branchetta 20, 51000 Rijeka, Croatia;
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Owiredu WKBA, Brenya PK, Osei Y, Laing EF, Okrah CO, Obirikorang C, Anto EO, Acheampong E, Donkor S. Evaluation of serum iron overload, AST:ALT ratio and log 10ferritin:AST ratio among schizophrenia patients in the Kumasi Metropolis, Ghana: a case-control study. BMC Res Notes 2019; 12:802. [PMID: 31831048 PMCID: PMC6909526 DOI: 10.1186/s13104-019-4847-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 12/06/2019] [Indexed: 01/07/2023] Open
Abstract
OBJECTIVE The association between unbalanced iron indices and the conditions of schizophrenia are not well understood. Liver dysfunction which has been linked to iron metabolism might be a contributing factor. This case-control study evaluated serum iron indices and liver function in treatment-naïve schizophrenia patients and those already on treatment at the Psychiatric Department of the Komfo Anokye Teaching Hospital (KATH), Kumasi-Ghana. RESULTS The mean age of the respondents was 39.6 ± 0.8 years. Increased levels of serum iron, TS, AST, ALT and AST:ALT ratio and lower levels of UIBC, TIBC, Transferrin, and log Ferritin:AST ratio levels were observed among the treatment-naïve group compared to the control. The treatment-naïve and treatment groups showed significantly higher serum AST:ALT ratio, and lower log10ferrtin:AST ratio than the healthy controls. There was a significant correlation between log10ferritin and AST, and log10ferritin and GGT in both treatments (r = 0.343; p = 0.003, and r = 0.502; p = 0.001 respectively) and treatment-naïve groups (r = 0.348; p = 0.002, and r = 0.614; p < 0.001 respectively). Percentage transferrin saturation correlated significantly with GGT only, in the treatment-naïve group (r = 0.667; p < 0.001), and ALT and GGT in the treatment group (r = 0.252; p = 0.030 and r = 0.646; p = 0.014 respectively).
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Affiliation(s)
- W K B A Owiredu
- Department of Molecular Medicine, KNUST School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
| | - Peter Kojo Brenya
- Department of Molecular Medicine, KNUST School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
| | - Yaw Osei
- Department of Physician Assistance, Faculty of Health and Allied Sciences, Garden City University College (GCUC), Kenyasi, Kumasi, Ghana
| | - Edwin Ferguson Laing
- Department of Molecular Medicine, KNUST School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
| | - Clement Opoku Okrah
- Department of Medical Laboratory Technology, Faculty of Allied Health Science, KNUST, Kumasi, Ghana
| | - Christian Obirikorang
- Department of Molecular Medicine, KNUST School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
| | - Enoch Odame Anto
- Department of Molecular Medicine, KNUST School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
- School of Medical and Health Sciences, Edith Cowan University (ECU), Joondalup, Perth-WA, Australia
| | - Emmanuel Acheampong
- Department of Molecular Medicine, KNUST School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
- School of Medical and Health Sciences, Edith Cowan University (ECU), Joondalup, Perth-WA, Australia
| | - Sampson Donkor
- Department of Molecular Medicine, KNUST School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana.
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12
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Griffin IJ, Eckman CB. The Effects of Iron in a Rodent Model of Alzheimer Disease. J Nutr 2019; 149:2079-2080. [PMID: 31504687 DOI: 10.1093/jn/nxz208] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 07/26/2019] [Accepted: 07/29/2019] [Indexed: 01/14/2023] Open
Affiliation(s)
- Ian J Griffin
- Department of Pediatrics, Morristown Medical Center, Morristown, NJ, USA.,Biomedical Research Institute of New Jersey, Cedar Knolls, NJ, USA
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