RESUMO
BACKGROUND: The NHS Health Check is a preventive programme in the UK designed to screen for cardiovascular risk and to aid in primary disease prevention. Despite its widespread implementation, the effectiveness of the NHS Health Check for longer-term disease prevention is unclear. In this study, we measured the rate of new diagnoses in UK Biobank participants who underwent the NHS Health Check compared with those who did not. METHODS: Within the UK Biobank prospective study, 48,602 NHS Health Check recipients were identified from linked primary care records. These participants were then covariate-matched on an extensive range of socio-demographic, lifestyle, and medical factors with 48,602 participants without record of the check. Follow-up diagnoses were ascertained from health records over an average of 9 years (SD 2 years) including hypertension, diabetes, hypercholesterolaemia, stroke, dementia, myocardial infarction, atrial fibrillation, heart failure, fatty liver disease, alcoholic liver disease, liver cirrhosis, liver failure, acute kidney injury, chronic kidney disease (stage 3 +), cardiovascular mortality, and all-cause mortality. Time-varying survival modelling was used to compare adjusted outcome rates between the groups. RESULTS: In the immediate 2 years after the NHS Health Check, higher diagnosis rates were observed for hypertension, high cholesterol, and chronic kidney disease among health check recipients compared to their matched counterparts. However, in the longer term, NHS Health Check recipients had significantly lower risk across all multiorgan disease outcomes and reduced rates of cardiovascular and all-cause mortality. CONCLUSIONS: The NHS Health Check is linked to reduced incidence of disease across multiple organ systems, which may be attributed to risk modification through earlier detection and treatment of key risk factors such as hypertension and high cholesterol. This work adds important evidence to the growing body of research supporting the effectiveness of preventative interventions in reducing longer-term multimorbidity.
Assuntos
Hipercolesterolemia , Hipertensão , Insuficiência Renal Crônica , Humanos , Estudos de Coortes , Estudos Prospectivos , Bancos de Espécimes Biológicos , Medicina Estatal , Biobanco do Reino Unido , Hipertensão/epidemiologia , ColesterolRESUMO
Increases in harmful drinking among older adults indicate the need for a more thorough understanding of the relationship between later-life alcohol use and brain health. The current study investigated the relationships between alcohol use and progressive grey and white matter changes in older adults using longitudinal data. A total of 530 participants (aged 70 to 90 years; 46.0% male) were included. Brain outcomes assessed over 6 years included total grey and white matter volume, as well as volume of the hippocampus, thalamus, amygdala, corpus callosum, orbitofrontal cortex and insula. White matter integrity was also investigated. Average alcohol use across the study period was the main exposure of interest. Past-year binge drinking and reduction in drinking from pre-baseline were additional exposures of interest. Within the context of low-level average drinking (averaging 11.7 g per day), higher average amount of alcohol consumed was associated with less atrophy in the left (B = 7.50, pFDR = 0.010) and right (B = 5.98, pFDR = 0.004) thalamus. Past-year binge-drinking was associated with poorer white matter integrity (B = -0.013, pFDR = 0.024). Consuming alcohol more heavily in the past was associated with greater atrophy in anterior (B = -12.73, pFDR = 0.048) and posterior (B = -17.88, pFDR = 0.004) callosal volumes over time. Across alcohol exposures and neuroimaging markers, no other relationships were statistically significant. Within the context of low-level drinking, very few relationships between alcohol use and brain macrostructure were identified. Meanwhile, heavier drinking was negatively associated with white matter integrity.
Assuntos
Consumo de Bebidas Alcoólicas , Atrofia , Encéfalo , Substância Cinzenta , Imageamento por Ressonância Magnética , Substância Branca , Humanos , Masculino , Idoso , Feminino , Estudos Longitudinais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/efeitos dos fármacos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Substância Branca/efeitos dos fármacos , Idoso de 80 Anos ou mais , Substância Cinzenta/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/efeitos dos fármacos , Atrofia/patologia , Envelhecimento/patologia , Envelhecimento/fisiologia , Consumo Excessivo de Bebidas Alcoólicas/patologia , Consumo Excessivo de Bebidas Alcoólicas/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Tálamo/patologia , Tálamo/efeitos dos fármacos , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Hipocampo/efeitos dos fármacos , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/patologia , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/patologia , Corpo Caloso/efeitos dos fármacosRESUMO
BACKGROUND: Brain iron deposition has been linked to several neurodegenerative conditions and reported in alcohol dependence. Whether iron accumulation occurs in moderate drinkers is unknown. Our objectives were to investigate evidence in support of causal relationships between alcohol consumption and brain iron levels and to examine whether higher brain iron represents a potential pathway to alcohol-related cognitive deficits. METHODS AND FINDINGS: Observational associations between brain iron markers and alcohol consumption (n = 20,729 UK Biobank participants) were compared with associations with genetically predicted alcohol intake and alcohol use disorder from 2-sample mendelian randomization (MR). Alcohol intake was self-reported via a touchscreen questionnaire at baseline (2006 to 2010). Participants with complete data were included. Multiorgan susceptibility-weighted magnetic resonance imaging (9.60 ± 1.10 years after baseline) was used to ascertain iron content of each brain region (quantitative susceptibility mapping (QSM) and T2*) and liver tissues (T2*), a marker of systemic iron. Main outcomes were susceptibility (χ) and T2*, measures used as indices of iron deposition. Brain regions of interest included putamen, caudate, hippocampi, thalami, and substantia nigra. Potential pathways to alcohol-related iron brain accumulation through elevated systemic iron stores (liver) were explored in causal mediation analysis. Cognition was assessed at the scan and in online follow-up (5.82 ± 0.86 years after baseline). Executive function was assessed with the trail-making test, fluid intelligence with puzzle tasks, and reaction time by a task based on the "Snap" card game. Mean age was 54.8 ± 7.4 years and 48.6% were female. Weekly alcohol consumption was 17.7 ± 15.9 units and never drinkers comprised 2.7% of the sample. Alcohol consumption was associated with markers of higher iron (χ) in putamen (ß = 0.08 standard deviation (SD) [95% confidence interval (CI) 0.06 to 0.09], p < 0.001), caudate (ß = 0.05 [0.04 to 0.07], p < 0.001), and substantia nigra (ß = 0.03 [0.02 to 0.05], p < 0.001) and lower iron in the thalami (ß = -0.06 [-0.07 to -0.04], p < 0.001). Quintile-based analyses found these associations in those consuming >7 units (56 g) alcohol weekly. MR analyses provided weak evidence these relationships are causal. Genetically predicted alcoholic drinks weekly positively associated with putamen and hippocampus susceptibility; however, these associations did not survive multiple testing corrections. Weak evidence for a causal relationship between genetically predicted alcohol use disorder and higher putamen susceptibility was observed; however, this was not robust to multiple comparisons correction. Genetically predicted alcohol use disorder was associated with serum iron and transferrin saturation. Elevated liver iron was observed at just >11 units (88 g) alcohol weekly c.f. <7 units (56 g). Systemic iron levels partially mediated associations of alcohol intake with brain iron. Markers of higher basal ganglia iron associated with slower executive function, lower fluid intelligence, and slower reaction times. The main limitations of the study include that χ and T2* can reflect changes in myelin as well as iron, alcohol use was self-reported, and MR estimates can be influenced by genetic pleiotropy. CONCLUSIONS: To the best of our knowledge, this study represents the largest investigation of moderate alcohol consumption and iron homeostasis to date. Alcohol consumption above 7 units weekly associated with higher brain iron. Iron accumulation represents a potential mechanism for alcohol-related cognitive decline.
Assuntos
Alcoolismo , Análise da Randomização Mendeliana , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/genética , Bancos de Espécimes Biológicos , Encéfalo/diagnóstico por imagem , Cognição , Feminino , Humanos , Ferro , Masculino , Análise da Randomização Mendeliana/métodos , Pessoa de Meia-Idade , Reino Unido/epidemiologiaRESUMO
BACKGROUND: Subjective cognitive complaints are common but it is unclear whether they indicate an underlying pathological process or reflect affective symptoms. METHOD: 800 community-dwelling older adults were drawn from the Whitehall II cohort. Subjective cognitive complaint inquiry for memory and concentration, a range of neuropsychological tests and multimodal MRI were performed in 2012-2016. Subjective complaints were again elicited after 1 year. Group differences in grey and white matter, between those with and without subjective complaints, were assessed using voxel-based morphometry and tract-based spatial statistics, respectively. Mixed effects models assessed whether cognitive decline or depressive symptoms (over a 25-year period) were associated with later subjective complaints. Analyses were controlled for potential confounders and multiple comparisons. RESULTS: Mean age of the sample at scanning was 69.8 years (±5.1, range: 60.3-84.6). Subjective memory complaints were common (41%) and predicted further similar complaints later (mean 1.4 ± 1.4 years). There were no group differences in grey matter density or white matter integrity. Subjective complaints were not cross-sectionally or longitudinally associated with objectively assessed cognition. However, those with subjective complaints reported higher depressive symptoms ("poor concentration": odds ratioâ¯=â¯1.12, 95% CI 1.07-1.18; "poor memory": odds ratioâ¯=â¯1.18, 1.12-1.24). CONCLUSIONS: In our sample subjective complaints were consistent over time and reflected depressive symptoms but not markers of neurodegenerative brain damage or concurrent or future objective cognitive impairment. Clinicians assessing patients presenting with memory complaints should be vigilant for affective disorders. These results question the rationale for including subjective complaints in a spectrum with Mild Cognitive Impairment diagnostic criteria.
Assuntos
Encéfalo/fisiopatologia , Cognição , Disfunção Cognitiva/fisiopatologia , Depressão/psicologia , Inquéritos Epidemiológicos , Transtornos da Memória/fisiopatologia , Autorrelato , Idoso , Idoso de 80 Anos ou mais , Encéfalo/anatomia & histologia , Encéfalo/patologia , Depressão/fisiopatologia , Feminino , Substância Cinzenta/anatomia & histologia , Substância Cinzenta/patologia , Substância Cinzenta/fisiopatologia , Humanos , Masculino , Testes Neuropsicológicos , Estudos Retrospectivos , Substância Branca/anatomia & histologia , Substância Branca/patologia , Substância Branca/fisiopatologiaRESUMO
OBJECTIVE: We aim to estimate the risk of perpetrating aggression in Alzheimer disease (AD) and mild cognitive impairment (MCI) by conducting a systematic review and meta-analysis of primary studies. METHODS: A systematic search was conducted in six bibliographic databases according to a preregistered protocol. Studies that reported aggressive behaviors in individuals with AD and MCI compared with healthy individuals or those with other dementia etiologies were identified. Risks of aggressive behaviors were assessed using random effects models to calculate pooled odds ratios (ORs). Publication bias was examined. RESULTS: In total, 17 studies involving 6,399 individuals with AD and 2,582 with MCI were identified. Compared with healthy individuals, significantly increased risks of aggressive behaviors were found in AD (OR, 4.9, 95% CI, 1.8-13.2) but not in MCI (OR, 1.8, 95% CI, 0.7-4.3). When comparing AD with MCI, the risk in AD was higher (OR, 2.6, 95% CI, 1.7-4.0). We found no differences in risk of aggressive behaviors between AD and other dementia subtypes or between amnestic and nonamnestic MCI. CONCLUSION: Individuals with AD are at higher risk of manifesting aggressive behaviors than healthy individuals or those with MCI. Our findings not only underscore the necessity of treatment of aggressive behaviors in AD but also highlight the importance of preventing the transition from MCI to AD.
Assuntos
Agressão/psicologia , Doença de Alzheimer/psicologia , Disfunção Cognitiva/psicologia , Progressão da Doença , Humanos , Testes NeuropsicológicosRESUMO
White matter hyperintensities (WMH) are frequently divided into periventricular (PWMH) and deep (DWMH), and the two classes have been associated with different cognitive, microstructural, and clinical correlates. However, although this distinction is widely used in visual ratings scales, how to best anatomically define the two classes is still disputed. In fact, the methods used to define PWMH and DWMH vary significantly between studies, making results difficult to compare. The purpose of this study was twofold: first, to compare four current criteria used to define PWMH and DWMH in a cohort of healthy older adults (mean age: 69.58 ± 5.33 years) by quantifying possible differences in terms of estimated volumes; second, to explore associations between the two WMH sub-classes with cognition, tissue microstructure and cardiovascular risk factors, analysing the impact of different criteria on the specific associations. Our results suggest that the classification criterion used for the definition of PWMH and DWMH should not be considered a major obstacle for the comparison of different studies. We observed that higher PWMH load is associated with reduced cognitive function, higher mean arterial pressure and age. Higher DWMH load is associated with higher body mass index. PWMH have lower fractional anisotropy than DWMH, which also have more heterogeneous microstructure. These findings support the hypothesis that PWMH and DWMH are different entities and that their distinction can provide useful information about healthy and pathological aging processes.
Assuntos
Envelhecimento , Índice de Massa Corporal , Disfunção Cognitiva/diagnóstico por imagem , Hipertensão/diagnóstico por imagem , Leucoaraiose/diagnóstico por imagem , Neuroimagem/métodos , Fatores Etários , Idoso , Envelhecimento/patologia , Disfunção Cognitiva/patologia , Estudos de Coortes , Feminino , Humanos , Hipertensão/patologia , Leucoaraiose/classificação , Leucoaraiose/patologia , Masculino , Pessoa de Meia-IdadeRESUMO
Episodic and spatial memory are commonly impaired in ageing and Alzheimer's disease. Volumetric and task-based functional magnetic resonance imaging (fMRI) studies suggest a preferential involvement of the medial temporal lobe (MTL), particularly the hippocampus, in episodic and spatial memory processing. The present study examined how these two memory types were related in terms of their associated resting-state functional architecture. 3T multiband resting state fMRI scans from 497 participants (60-82 years old) of the cross-sectional Whitehall II Imaging sub-study were analysed using an unbiased, data-driven network-modelling technique (FSLNets). Factor analysis was performed on the cognitive battery; the Hopkins Verbal Learning test and Rey-Osterreith Complex Figure test factors were used to assess verbal and visuospatial memory respectively. We present a map of the macroscopic functional connectome for the Whitehall II Imaging sub-study, comprising 58 functionally distinct nodes clustered into five major resting-state networks. Within this map we identified distinct functional connections associated with verbal and visuospatial memory. Functional anticorrelation between the hippocampal formation and the frontal pole was significantly associated with better verbal memory in an age-dependent manner. In contrast, hippocampus-motor and parietal-motor functional connections were associated with visuospatial memory independently of age. These relationships were not driven by grey matter volume and were unique to the respective memory domain. Our findings provide new insights into current models of brain-behaviour interactions, and suggest that while both episodic and visuospatial memory engage MTL nodes of the default mode network, the two memory domains differ in terms of the associated functional connections between the MTL and other resting-state brain networks.
Assuntos
Encéfalo/fisiologia , Memória Episódica , Vias Neurais/fisiologia , Memória Espacial/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , DescansoRESUMO
Both sleep disturbances and decline in white matter microstructure are commonly observed in ageing populations, as well as in age-related psychiatric and neurological illnesses. A relationship between sleep and white matter microstructure may underlie such relationships, but few imaging studies have directly examined this hypothesis. In a study of 448 community-dwelling members of the Whitehall II Imaging Sub-Study aged between 60 and 82 years (90 female, mean age 69.2 ± 5.1 years), we used the magnetic resonance imaging technique diffusion tensor imaging to examine the relationship between self-reported sleep quality and white matter microstructure. Poor sleep quality at the time of the diffusion tensor imaging scan was associated with reduced global fractional anisotropy and increased global axial diffusivity and radial diffusivity values, with small effect sizes. Voxel-wise analysis showed that widespread frontal-subcortical tracts, encompassing regions previously reported as altered in insomnia, were affected. Radial diffusivity findings remained significant after additional correction for demographics, general cognition, health, and lifestyle measures. No significant differences in general cognitive function, executive function, memory, or processing speed were detected between good and poor sleep quality groups. The number of times participants reported poor sleep quality over five time-points spanning a 16-year period was not associated with white matter measures. In conclusion, these data demonstrate that current sleep quality is linked to white matter microstructure. Small effect sizes may limit the extent to which poor sleep is a promising modifiable factor that may maintain, or even improve, white matter microstructure in ageing. Hum Brain Mapp 38:5465-5473, 2017. © 2017 Wiley Periodicals, Inc.
Assuntos
Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão , Imageamento por Ressonância Magnética , Transtornos do Sono-Vigília/diagnóstico por imagem , Sono , Substância Branca/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/patologia , Encéfalo/patologia , Feminino , Humanos , Vida Independente , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Autorrelato , Transtornos do Sono-Vigília/patologia , Substância Branca/patologiaRESUMO
BACKGROUND: The contribution of education and intelligence to resilience against age-related cognitive decline is not clear, particularly in the presence of 'normal for age' minor brain abnormalities. METHOD: Participants (n = 208, mean age 69.2 years, s.d. = 5.4) in the Whitehall II imaging substudy attended for neuropsychological testing and multisequence 3T brain magnetic resonance imaging. Images were independently rated by three trained clinicians for global and hippocampal atrophy, periventricular and deep white matter changes. RESULTS: Although none of the participants qualified for a clinical diagnosis of dementia, a screen for cognitive impairment (Montreal Cognitive Assessment (MoCA) <26) was abnormal in 22%. Hippocampal atrophy, in contrast to other brain measures, was associated with a reduced MoCA score even after controlling for age, gender, socioeconomic status, years of education and premorbid IQ. Premorbid IQ and socioeconomic status were associated with resilience in the presence of hippocampal atrophy. CONCLUSIONS: Independent contributions from a priori risk (age, hippocampal atrophy) and resilience (premorbid function, socioeconomic status) combine to predict measured cognitive impairment.
Assuntos
Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Hipocampo/patologia , Resiliência Psicológica , Idoso , Atrofia/patologia , Estudos de Coortes , Feminino , Humanos , Modelos Logísticos , Londres , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes NeuropsicológicosRESUMO
BACKGROUND: Hypertension is associated with an increased risk of dementia and depression with uncertain longitudinal associations with brain structure. AIMS: To examine lifetime blood pressure as a predictor of brain structure in old age. METHOD: A total of 190 participants (mean age 69.3 years) from the Whitehall II study were screened for hypertension six times (1985-2013). In 2012-2013, participants had a 3T-magnetic resonance imaging (MRI) brain scan. Data from the MRI were analysed using automated and visual measures of global atrophy, hippocampal atrophy and white matter hyperintensities. RESULTS: Longitudinally, higher mean arterial pressure predicted increased automated white matter hyperintensities (P<0.002). Cross-sectionally, hypertensive participants had increased automated white matter hyperintensities and visually rated deep white matter hyperintensities. There was no significant association with global or hippocampal atrophy. CONCLUSIONS: Long-term exposure to high blood pressure predicts hyperintensities, particularly in deep white matter. The greatest changes are seen in those with severe forms of hypertension, suggesting a dose-response pattern.
Assuntos
Encéfalo/diagnóstico por imagem , Hipertensão/complicações , Hipertensão/diagnóstico , Imageamento por Ressonância Magnética , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Atrofia , Pressão Sanguínea , Transtornos Cognitivos/complicações , Estudos de Coortes , Estudos Transversais , Demência/complicações , Transtorno Depressivo/complicações , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Fatores de Risco , Distribuição por SexoRESUMO
Common causes of memory loss in older people are mild cognitive impairment, the various types of dementia, and psychiatric illness, mainly depression. Around 10% of patients with mild cognitive impairment progress to dementia each year. Alzheimer's disease accounts for 60-80% of cases. Other common types of dementia are vascular, fronto-temporal, Lewy body, Parkinson's, and mixed type dementia. There is evidence to suggest that dementia pathology is established before the onset of symptoms, and thus mild cognitive impairment can be considered as a predementia stage. NICE guidance suggests examination of: attention, concentration, short- and long-term memory, praxis, language and executive function. Particular attention should be paid to any signs of neglect, state of dress, agitation or poor attention. Dysphasia and difficulty in naming objects is often present. Mood symptoms (including suicidal ideation) may be primary or comorbid. Abnormal thoughts and perceptions should be probed for, as psychotic symptoms are common. Primary care options for cognitive testing include the General Practitioner Assessment of Cognition or the Abbreviated Mental Test Score. Physical examination should include observation of gait, inspection for tremor; examination for rigidity, bradykinesia, frontal release signs, upper motor neurone lesions, pulse and BP. Structural brain imaging can improve diagnostic accuracy, exclude other pathologies and act as a prognostic marker of dementia progression but the overlap in structural changes between the dementias makes imaging alone insufficient for diagnostic purposes. NICE guidelines recommend referral to a memory clinic for patients with mild cognitive impairment, those at high risk of dementia, such as patients with learning disabilities, Parkinson's disease, or patients who have had several strokes.
Assuntos
Transtornos da Memória/diagnóstico , Idoso , Humanos , Transtornos da Memória/etiologia , Transtornos da Memória/terapia , Encaminhamento e Consulta , Fatores de RiscoRESUMO
Dementia is one of the major causes of personal, societal and financial dependence in older people and in today's ageing society there is a pressing need for early and accurate markers of cognitive decline. There are several subtypes of dementia but the four most common are Alzheimer's disease, Lewy body dementia, vascular dementia and frontotemporal dementia. These disorders can only be diagnosed at autopsy, and ante-mortem assessments of "probable dementia (e.g. of Alzheimer type)" are traditionally driven by clinical symptoms of cognitive or behavioural deficits. However, owing to the overlapping nature of symptoms and age of onset, a significant proportion of dementia cases remain incorrectly diagnosed. Misdiagnosis can have an extensive impact, both at the level of the individual, who may not be offered the appropriate treatment, and on a wider scale, by influencing the entry of patients into relevant clinical trials. Magnetic resonance imaging (MRI) may help to improve diagnosis by providing non-invasive and detailed disease-specific markers of cognitive decline. MRI-derived measurements of grey and white matter structural integrity are potential surrogate markers of disease progression, and may also provide valuable diagnostic information. This review summarises the latest evidence on the use of structural and diffusion MRI in differentiating between the four major dementia subtypes.
Assuntos
Encéfalo/patologia , Demência/diagnóstico , Imagem de Difusão por Ressonância Magnética , Imageamento por Ressonância Magnética , Atrofia , Humanos , Processamento de Imagem Assistida por ComputadorRESUMO
BACKGROUND: The Whitehall II (WHII) study of British civil servants provides a unique source of longitudinal data to investigate key factors hypothesized to affect brain health and cognitive ageing. This paper introduces the multi-modal magnetic resonance imaging (MRI) protocol and cognitive assessment designed to investigate brain health in a random sample of 800 members of the WHII study. METHODS/DESIGN: A total of 6035 civil servants participated in the WHII Phase 11 clinical examination in 2012-2013. A random sample of these participants was included in a sub-study comprising an MRI brain scan, a detailed clinical and cognitive assessment, and collection of blood and buccal mucosal samples for the characterisation of immune function and associated measures. Data collection for this sub-study started in 2012 and will be completed by 2016. The participants, for whom social and health records have been collected since 1985, were between 60-85 years of age at the time the MRI study started. Here, we describe the pre-specified clinical and cognitive assessment protocols, the state-of-the-art MRI sequences and latest pipelines for analyses of this sub-study. DISCUSSION: The integration of cutting-edge MRI techniques, clinical and cognitive tests in combination with retrospective data on social, behavioural and biological variables during the preceding 25 years from a well-established longitudinal epidemiological study (WHII cohort) will provide a unique opportunity to examine brain structure and function in relation to age-related diseases and the modifiable and non-modifiable factors affecting resilience against and vulnerability to adverse brain changes.
Assuntos
Envelhecimento/patologia , Encéfalo/patologia , Transtornos Cognitivos/patologia , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Cognição , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
OBJECTIVE: Metabolic syndrome (MetS) has been linked to dementia. In this study, we examined the association of MetS with neuroimaging and cognition in dementia-free adults, offering insight into the impact of MetS on brain health prior to dementia onset. RESEARCH DESIGN AND METHODS: We included 37,395 dementia-free adults from the UK Biobank database. MetS was defined as having at least three of the following components: larger waist circumference; elevated levels of triglycerides, blood pressure, HbA1c; or reduced HDL cholesterol levels. Multivariable-adjusted linear regression was used to assess associations of MetS with structural neuroimaging and cognitive domains. RESULTS: MetS was associated with lower total brain (standardized ß: -0.06; 95% CI -0.08, -0.04), gray matter (ß: -0.10; 95% CI -0.12, -0.08) and hippocampal (for left side, ß: -0.03, 95% CI -0.05, -0.01; for right side, ß: -0.04, 95% CI -0.07, -0.02) volumes, and greater white matter hyperintensity (WMH) volume (ß: 0.08; 95% CI 0.06, 0.11). Study participants with MetS performed poorer on cognitive tests of working memory (ß: -0.10; 95% CI -0.13, -0.07), verbal declarative memory (ß: -0.08; 95% CI -0.11, -0.05), processing speed (ß: -0.06; 95% CI -0.09, -0.04), verbal and numerical reasoning (ß: -0.07; 95% CI -0.09, -0.04), nonverbal reasoning (ß: -0.03; 95% CI -0.05, -0.01), and on tests of executive function, where higher scores indicated poorer performance (ß: 0.05; 95% CI 0.03, 0.08). More MetS components were also associated with less brain volume, greater WMH, and poorer cognition across all domains. CONCLUSIONS: MetS was associated poorer brain health in dementia-free adults, characterized by less brain volume, greater vascular pathology, and poorer cognition. Further research is necessary to understand whether reversal or improvement of MetS can improve brain health.
Assuntos
Bancos de Espécimes Biológicos , Cognição , Síndrome Metabólica , Neuroimagem , Humanos , Masculino , Síndrome Metabólica/epidemiologia , Feminino , Pessoa de Meia-Idade , Neuroimagem/métodos , Cognição/fisiologia , Reino Unido/epidemiologia , Idoso , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Biobanco do Reino UnidoRESUMO
OBJECTIVES: Preservation of brain health is an urgent priority for the world's ageing population. The evidence base for brain health optimisation strategies is rapidly expanding, but clear recommendations have been limited by heterogeneity in measurement of brain health outcomes. We performed a scoping review to systematically evaluate brain health measurement in the scientific literature to date, informing development of a core outcome set. DESIGN: Scoping review. DATA SOURCES: Medline, APA PsycArticles and Embase were searched through until 25 January 2023. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Studies were included if they described brain health evaluation methods in sufficient detail in human adults and were in English language. DATA EXTRACTION AND SYNTHESIS: Two reviewers independently screened titles, abstracts and full texts for inclusion and extracted data using Covidence software. RESULTS: From 6987 articles identified by the search, 727 studies met inclusion criteria. Study publication increased by 22 times in the last decade. Cohort study was the most common study design (n=609, 84%). 479 unique methods of measuring brain health were identified, comprising imaging, cognitive, mental health, biological and clinical categories. Seven of the top 10 most frequently used brain health measurement methods were imaging based, including structural imaging of grey matter and hippocampal volumes and white matter hyperintensities. Cognitive tests such as the trail making test accounted for 286 (59.7%) of all brain health measurement methods. CONCLUSIONS: The scientific literature surrounding brain health has increased exponentially, yet measurement methods are highly heterogeneous across studies which may explain the lack of clinical translation. Future studies should aim to develop a selected group of measures that should be included in all brain health studies to aid interstudy comparison (core outcome set), and broaden from the current focus on neuroimaging outcomes to include a range of outcomes.
Assuntos
Encéfalo , Hipocampo , Adulto , Humanos , Estudos de Coortes , Encéfalo/diagnóstico por imagem , Projetos de Pesquisa , NeuroimagemRESUMO
OBJECTIVES: Despite rising rates of multimorbidity, existing risk assessment tools are mostly limited to a single outcome of interest. This study tests the feasibility of producing multiple disease risk estimates with at least 70% discrimination (area under the receiver operating curve, AUROC) within the time and information constraints of the existing primary care health check framework. DESIGN: Observational prospective cohort study SETTING: UK Biobank. PARTICIPANTS: 228 240 adults from the UK population. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Myocardial infarction, atrial fibrillation, heart failure, stroke, all-cause dementia, chronic kidney disease, fatty liver disease, alcoholic liver disease, liver cirrhosis and liver failure. RESULTS: Using a set of predictors easily gathered at the standard primary care health check (such as the National Health Service Health Check), we demonstrate that it is feasible to simultaneously produce risk estimates for multiple disease outcomes with AUROC of 70% or greater. These predictors can be entered once into a single form and produce risk scores for stroke (AUROC 0.727, 95% CI 0.713 to 0.740), all-cause dementia (0.823, 95% CI 0.810 to 0.836), myocardial infarction (0.785, 95% CI 0.775 to 0.795), atrial fibrillation (0.777, 95% CI 0.768 to 0.785), heart failure (0.828, 95% CI 0.818 to 0.838), chronic kidney disease (0.774, 95% CI 0.765 to 0.783), fatty liver disease (0.766, 95% CI 0.753 to 0.779), alcoholic liver disease (0.864, 95% CI 0.835 to 0.894), liver cirrhosis (0.763, 95% CI 0.734 to 0.793) and liver failure (0.746, 95% CI 0.695 to 0.796). CONCLUSIONS: Easily collected diagnostics can be used to assess 10-year risk across multiple disease outcomes, without the need for specialist computing or invasive biomarkers. Such an approach could increase the utility of existing data and place multiorgan risk information at the fingertips of primary care providers, thus creating opportunities for longer-term multimorbidity prevention. Additional work is needed to validate whether these findings would hold in a larger, more representative cohort outside the UK Biobank.
RESUMO
Telomeres form protective caps at the ends of chromosomes, and their attrition is a marker of biological aging. Short telomeres are associated with an increased risk of neurological and psychiatric disorders including dementia. The mechanism underlying this risk is unclear, and may involve brain structure and function. However, the relationship between telomere length and neuroimaging markers is poorly characterized. Here we show that leucocyte telomere length (LTL) is associated with multi-modal MRI phenotypes in 31,661 UK Biobank participants. Longer LTL is associated with: i) larger global and subcortical grey matter volumes including the hippocampus, ii) lower T1-weighted grey-white tissue contrast in sensory cortices, iii) white-matter microstructure measures in corpus callosum and association fibres, iv) lower volume of white matter hyperintensities, and v) lower basal ganglia iron. Longer LTL was protective against certain related clinical manifestations, namely all-cause dementia (HR 0.93, 95% CI: 0.91-0.96), but not stroke or Parkinson's disease. LTL is associated with multiple MRI endophenotypes of neurodegenerative disease, suggesting a pathway by which longer LTL may confer protective against dementia.
Assuntos
Demência , Doenças Neurodegenerativas , Humanos , Bancos de Espécimes Biológicos , Encéfalo/diagnóstico por imagem , Fenótipo , Telômero/genética , Neuroimagem , Reino Unido , Demência/diagnóstico por imagem , Demência/genética , LeucócitosRESUMO
Studies of neurodegenerative disease risk in gout are contradictory. Relationships with neuroimaging markers of brain structure, which may offer insights, are uncertain. Here we investigated associations between gout, brain structure, and neurodegenerative disease incidence. Gout patients had smaller global and regional brain volumes and markers of higher brain iron, using both observational and genetic approaches. Participants with gout also had higher incidence of all-cause dementia, Parkinson's disease, and probable essential tremor. Risks were strongly time dependent, whereby associations with incident dementia were highest in the first 3 years after gout diagnosis. These findings suggest gout is causally related to several measures of brain structure. Lower brain reserve amongst gout patients may explain their higher vulnerability to multiple neurodegenerative diseases. Motor and cognitive impairments may affect gout patients, particularly in early years after diagnosis.
Assuntos
Reserva Cognitiva , Demência , Gota , Doenças Neurodegenerativas , Humanos , Gota/complicações , Encéfalo/diagnóstico por imagem , Demência/epidemiologiaRESUMO
BACKGROUND: Current dementia risk scores have had limited success in consistently identifying at-risk individuals across different ages and geographical locations. OBJECTIVE: We aimed to develop and validate a novel dementia risk score for a midlife UK population, using two cohorts: the UK Biobank, and UK Whitehall II study. METHODS: We divided the UK Biobank cohort into a training (n=176 611, 80%) and test sample (n=44 151, 20%) and used the Whitehall II cohort (n=2934) for external validation. We used the Cox LASSO regression to select the strongest predictors of incident dementia from 28 candidate predictors and then developed the risk score using competing risk regression. FINDINGS: Our risk score, termed the UK Biobank Dementia Risk Score (UKBDRS), consisted of age, education, parental history of dementia, material deprivation, a history of diabetes, stroke, depression, hypertension, high cholesterol, household occupancy, and sex. The score had a strong discrimination accuracy in the UK Biobank test sample (area under the curve (AUC) 0.8, 95% CI 0.78 to 0.82) and in the Whitehall cohort (AUC 0.77, 95% CI 0.72 to 0.81). The UKBDRS also significantly outperformed three other widely used dementia risk scores originally developed in cohorts in Australia (the Australian National University Alzheimer's Disease Risk Index), Finland (the Cardiovascular Risk Factors, Ageing, and Dementia score), and the UK (Dementia Risk Score). CLINICAL IMPLICATIONS: Our risk score represents an easy-to-use tool to identify individuals at risk for dementia in the UK. Further research is required to determine the validity of this score in other populations.
Assuntos
Bancos de Espécimes Biológicos , Demência , Humanos , Austrália , Fatores de Risco , Demência/diagnóstico , Reino Unido/epidemiologiaRESUMO
Alcohol-related liver disease (ARLD) represents a major public health burden. Identification of high-risk individuals would allow efficient targeting of public health interventions. Here, we show significant interactions between pattern of drinking, genetic predisposition (polygenic risk score, PRS) and diabetes mellitus, and risk of incident ARLD, in 312,599 actively drinking adults in UK Biobank. Binge and heavy binge drinking significantly increase the risk of alcohol-related cirrhosis (ARC), with higher genetic predisposition further amplifying the risk. Further, we demonstrate a pronounced interaction between heavy binge drinking and high PRS, resulting in a relative excess risk due to interaction (RERI) of 6.07. Diabetes consistently elevates ARC risk across all drinking and PRS categories, and showed significant interaction with both binge patterns and genetic risk. Overall, we demonstrate synergistic effects of binge drinking, genetics, and diabetes on ARC, with potential to identify high-risk individuals for targeted interventions.