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1.
Artigo em Inglês | MEDLINE | ID: mdl-38569877

RESUMO

BACKGROUND: Hearing loss has been proposed as a modifiable risk factor for dementia. However, the relationship between hearing, neurodegeneration, and cognitive change, and the extent to which pathological processes such as Alzheimer's disease and cerebrovascular disease influence these relationships, is unclear. METHODS: Data from 287 adults born in the same week of 1946 who underwent baseline pure tone audiometry (mean age=70.6 years) and two time point cognitive assessment/multimodal brain imaging (mean interval 2.4 years) were analysed. Hearing impairment at baseline was defined as a pure tone average of greater than 25 decibels in the best hearing ear. Rates of change for whole brain, hippocampal and ventricle volume were estimated from structural MRI using the Boundary Shift Integral. Cognition was assessed using the Pre-clinical Alzheimer's Cognitive Composite. Regression models were performed to evaluate how baseline hearing impairment associated with subsequent brain atrophy and cognitive decline after adjustment for a range of confounders including baseline ß-amyloid deposition and white matter hyperintensity volume. RESULTS: 111 out of 287 participants had hearing impairment. Compared with those with preserved hearing, hearing impaired individuals had faster rates of whole brain atrophy, and worse hearing (higher pure tone average) predicted faster rates of hippocampal atrophy. In participants with hearing impairment, faster rates of whole brain atrophy predicted greater cognitive change. All observed relationships were independent of ß-amyloid deposition and white matter hyperintensity volume. CONCLUSIONS: Hearing loss may influence dementia risk via pathways distinct from those typically implicated in Alzheimer's and cerebrovascular disease in cognitively unimpaired older adults.

2.
J Neurol Neurosurg Psychiatry ; 95(8): 748-752, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38199813

RESUMO

BACKGROUND: Consistent patterns of reduced cortical thickness have been identified in early Alzheimer's disease (AD). However, the pathological factors that influence rates of cortical thinning within these AD signature regions remain unclear. METHODS: Participants were from the Insight 46 substudy of the MRC National Survey of Health and Development (NSHD; 1946 British birth cohort), a prospective longitudinal cohort study. Linear regression was used to examine associations of baseline cerebral ß-amyloid (Aß) deposition, measured using florbetapir positron emission tomography, and baseline white matter hyperintensity volume (WMHV) on MRI, a marker of cerebral small vessel disease, with subsequent longitudinal changes in AD signature cortical thickness quantified from baseline and repeat MRI (mean [SD] interval 2.4 [0.2] years). RESULTS: In a population-based sample of 337 cognitively normal older white adults (mean [SD] age at baseline 70.5 [0.6] years; 48.1% female), higher global WMHV at baseline related to faster subsequent rates of cortical thinning in both AD signature regions (~0.15%/year faster per 10 mL additional WMHV), whereas baseline Aß status did not. Among Aß positive participants (n=56), there was some evidence that greater global Aß standardised uptake value ratio at baseline related to faster cortical thinning in the AD signature Mayo region, but this did not reach statistical significance (p=0.08). CONCLUSIONS: Cortical thinning within AD signature regions may develop via cerebrovascular pathways. Perhaps reflecting the age of the cohort and relatively low prevalence of Aß-positivity, robust Aß-related differences were not detected. Longitudinal follow-up incorporating additional biomarkers will allow assessment of how these relationships evolve closer to expected dementia onset.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Afinamento Cortical Cerebral , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Substância Branca , Humanos , Feminino , Masculino , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Estudos Longitudinais , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Afinamento Cortical Cerebral/diagnóstico por imagem , Afinamento Cortical Cerebral/patologia , Estudos Prospectivos , Etilenoglicóis , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Córtex Cerebral/metabolismo , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/patologia , Compostos de Anilina
3.
BMC Neurol ; 24(1): 40, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263061

RESUMO

BACKGROUND: Although age is the biggest known risk factor for dementia, there remains uncertainty about other factors over the life course that contribute to a person's risk for cognitive decline later in life. Furthermore, the pathological processes leading to dementia are not fully understood. The main goals of Insight 46-a multi-phase longitudinal observational study-are to collect detailed cognitive, neurological, physical, cardiovascular, and sensory data; to combine those data with genetic and life-course information collected from the MRC National Survey of Health and Development (NSHD; 1946 British birth cohort); and thereby contribute to a better understanding of healthy ageing and dementia. METHODS/DESIGN: Phase 1 of Insight 46 (2015-2018) involved the recruitment of 502 members of the NSHD (median age = 70.7 years; 49% female) and has been described in detail by Lane and Parker et al. 2017. The present paper describes phase 2 (2018-2021) and phase 3 (2021-ongoing). Of the 502 phase 1 study members who were invited to a phase 2 research visit, 413 were willing to return for a clinic visit in London and 29 participated in a remote research assessment due to COVID-19 restrictions. Phase 3 aims to recruit 250 study members who previously participated in both phases 1 and 2 of Insight 46 (providing a third data time point) and 500 additional members of the NSHD who have not previously participated in Insight 46. DISCUSSION: The NSHD is the oldest and longest continuously running British birth cohort. Members of the NSHD are now at a critical point in their lives for us to investigate successful ageing and key age-related brain morbidities. Data collected from Insight 46 have the potential to greatly contribute to and impact the field of healthy ageing and dementia by combining unique life course data with longitudinal multiparametric clinical, imaging, and biomarker measurements. Further protocol enhancements are planned, including in-home sleep measurements and the engagement of participants through remote online cognitive testing. Data collected are and will continue to be made available to the scientific community.


Assuntos
Demência , Idoso , Feminino , Humanos , Masculino , Envelhecimento , Assistência Ambulatorial , Encéfalo , Estudos Observacionais como Assunto
4.
J Neurol Neurosurg Psychiatry ; 94(9): 742-750, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37080759

RESUMO

BACKGROUND: Dementia is a common and devastating symptom of Parkinson's disease (PD). Visual function and retinal structure are both emerging as potentially predictive for dementia in Parkinson's but lack longitudinal evidence. METHODS: We prospectively examined higher order vision (skew tolerance and biological motion) and retinal thickness (spectral domain optical coherence tomography) in 100 people with PD and 29 controls, with longitudinal cognitive assessments at baseline, 18 months and 36 months. We examined whether visual and retinal baseline measures predicted longitudinal cognitive scores using linear mixed effects models and whether they predicted onset of dementia, death and frailty using time-to-outcome methods. RESULTS: Patients with PD with poorer baseline visual performance scored lower on a composite cognitive score (ß=0.178, SE=0.05, p=0.0005) and showed greater decreases in cognition over time (ß=0.024, SE=0.001, p=0.013). Poorer visual performance also predicted greater probability of dementia (χ² (1)=5.2, p=0.022) and poor outcomes (χ² (1) =10.0, p=0.002). Baseline retinal thickness of the ganglion cell-inner plexiform layer did not predict cognitive scores or change in cognition with time in PD (ß=-0.013, SE=0.080, p=0.87; ß=0.024, SE=0.001, p=0.12). CONCLUSIONS: In our deeply phenotyped longitudinal cohort, visual dysfunction predicted dementia and poor outcomes in PD. Conversely, retinal thickness had less power to predict dementia. This supports mechanistic models for Parkinson's dementia progression with onset in cortical structures and shows potential for visual tests to enable stratification for clinical trials.


Assuntos
Disfunção Cognitiva , Demência , Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Retina/diagnóstico por imagem , Transtornos da Visão/etiologia , Demência/complicações , Disfunção Cognitiva/etiologia
5.
Biometrics ; 79(3): 2417-2429, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-35731973

RESUMO

A central challenge of medical imaging studies is to extract biomarkers that characterize disease pathology or outcomes. Modern automated approaches have found tremendous success in high-resolution, high-quality magnetic resonance images. These methods, however, may not translate to low-resolution images acquired on magnetic resonance imaging (MRI) scanners with lower magnetic field strength. In low-resource settings where low-field scanners are more common and there is a shortage of radiologists to manually interpret MRI scans, it is critical to develop automated methods that can augment or replace manual interpretation, while accommodating reduced image quality. We present a fully automated framework for translating radiological diagnostic criteria into image-based biomarkers, inspired by a project in which children with cerebral malaria (CM) were imaged using low-field 0.35 Tesla MRI. We integrate multiatlas label fusion, which leverages high-resolution images from another sample as prior spatial information, with parametric Gaussian hidden Markov models based on image intensities, to create a robust method for determining ventricular cerebrospinal fluid volume. We also propose normalized image intensity and texture measurements to determine the loss of gray-to-white matter tissue differentiation and sulcal effacement. These integrated biomarkers have excellent classification performance for determining severe brain swelling due to CM.


Assuntos
Malária Cerebral , Criança , Humanos , Malária Cerebral/diagnóstico por imagem , Malária Cerebral/patologia , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos
6.
Br J Nutr ; 130(9): 1609-1624, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36912073

RESUMO

Frequent ultra-processed food (UPF) consumption is consistently associated with poor health outcomes. Little is known about UPF intake during early childhood and its effects on growth. We assessed UPF in relation to child anthropometry, bone maturation, and their nutrition profiles in a rural Ecuadorian community. Covariate-adjusted regression models estimated relationships between UPF intake from a 24-hour Food Frequency Questionnaire and three outcomes: linear growth, weight status and bone maturation. Nutrient Profiling Models (NPM) evaluated a convenience sample of UPF (n 28) consumed by children in the community. In this cohort (n 125; mean age = 33·92 (sd 1·75) months), 92·8 % consumed some form of UPF the previous day. On average, children consuming UPF four to twelve times per day (highest tertile) had lower height-for-age z-scores than those with none or a single instance of UPF intake (lowest tertile) (ß = -0·43 [se 0·18]; P = 0·02). Adjusted stunting odds were significantly higher in the highest tertile relative to the lowest tertile (OR: 3·07, 95 % CI 1·11, 9·09). Children in the highest tertile had significantly higher bone age z-scores (BAZ) on average compared with the lowest tertile (ß = 0·58 [se 0·25]; P = 0·03). Intake of savoury UPF was negatively associated with weight-for-height z-scores (ß = -0·30 [se 0·14]; P = 0·04) but positively associated with BAZ (ß = 0·77 [se 0·23]; P < 0·001). NPM indicated the availability of unhealthy UPF to children, with excessive amounts of saturated fats, free sugars and sodium. Findings suggest that frequent UPF intake during early childhood may be linked to stunted growth (after controlling for bone age and additional covariates), despite paradoxical associations with bone maturation.


Assuntos
Dieta , Alimento Processado , Humanos , Criança , Pré-Escolar , Adulto , Equador , Fast Foods , Manipulação de Alimentos , Antropometria
7.
Ethn Health ; 28(6): 822-835, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36935189

RESUMO

OBJECTIVES: Children with Type 1 diabetes (T1D) from different ethnic backgrounds are growing in proportion in clinical practice and tend to have a higher risk of poor health outcomes. The study aimed to investigate the perspectives of culturally and linguistically diverse families in the management of children with T1D in Western Australia. DESIGN: A generic qualitative approach was used. Families of children and adolescents with T1D with first-generation African, Asian or Middle Eastern background were invited to participate in a semi-structured interview. The interviews were audio-recorded, transcribed and analysed thematically. Demographic, clinical and socio-economic data were collected from all participants. RESULTS: Fifteen families (27% African, 33% Middle Eastern, 40% Asian) participated in the study. The mean (SD) age of the child with T1D was 10.2 (5.1) years, had diabetes for 2.9 (1.6) years and an average HbA1c of 67 (15) mmol/mol. Four main themes were identified through qualitative analysis. 'Dietary challenges': lack of adequate food resources posed a barrier to determine carbohydrate amount in traditional meals; 'Linguistic challenges': inadequate reading and language skills affected comprehension of written information and the desire for pictorial resources was reported; 'Limited Support': absence of extended family made management of T1D difficult; and 'Knowledge': a key facilitator, which was acquired through clinic education, enabled families to develop skills to effectively manage T1D. CONCLUSION: The study highlights the need to consider cultural diversity, psychosocial needs, English proficiency and health literacy when assessing and planning diabetes education. These findings will be useful to formulate a more culturally sensitive approach to diabetes education to improve care and outcomes for young people with T1D from culturally and linguistically diverse families.


Assuntos
Diabetes Mellitus Tipo 1 , Adolescente , Humanos , Criança , Austrália Ocidental , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 1/psicologia , Diversidade Cultural , Etnicidade , Dieta , Pesquisa Qualitativa
8.
J Med Internet Res ; 25: e47860, 2023 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-38090786

RESUMO

BACKGROUND: Repetitive negative thinking (RNT) is a key transdiagnostic mechanism underpinning depression and anxiety. Using "just-in-time adaptive interventions" via smartphones may disrupt RNT in real time, providing targeted and personalized intervention. OBJECTIVE: This pilot randomized controlled trial evaluates the feasibility, acceptability, and preliminary clinical outcomes and mechanisms of Mello-a fully automated, personalized, transdiagnostic, and mechanistic smartphone intervention targeting RNT in young people with depression and anxiety. METHODS: Participants with heightened depression, anxiety, and RNT were recruited via social media and randomized to receive Mello or a nonactive control over a 6-week intervention period. Assessments were completed via Zoom sessions at baseline and at 3 and 6 weeks after baseline. RESULTS: The findings supported feasibility and acceptability, with high rates of recruitment (N=55), uptake (55/64, 86% of eligible participants), and retention (52/55, 95% at 6 weeks). Engagement was high, with 90% (26/29) and 59% (17/29) of the participants in the Mello condition still using the app during the third and sixth weeks, respectively. Greater reductions in depression (Cohen d=0.50), anxiety (Cohen d=0.61), and RNT (Cohen d=0.87) were observed for Mello users versus controls. Mediation analyses suggested that changes in depression and anxiety were accounted for by changes in RNT. CONCLUSIONS: The results indicate that mechanistic, targeted, and real-time technology-based solutions may provide scalable and effective interventions that advance the treatment of youth mental ill health. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12621001701819; http://tinyurl.com/4d3jfj9f.


Assuntos
Pessimismo , Smartphone , Adolescente , Humanos , Depressão/diagnóstico , Depressão/terapia , Projetos Piloto , Austrália , Ansiedade/terapia , Ansiedade/diagnóstico
9.
Australas Psychiatry ; 31(3): 302-305, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37072342

RESUMO

OBJECTIVE: Integrating digital technologies with clinical practice promises to improve access and enhance care in the context of high service demand and constrained capacity. METHOD: We outline the emerging research in the integration of digital tools in clinical care, known as blended care, and provide case examples of mental health technology platforms currently in use, summarise findings regarding novel technologies such as virtual reality, and outline real-world implementation challenges and potential solutions. RESULTS: Recent evidence shows that blended care approaches are clinically effective and improve service efficiency. Youth-specific technologies such as moderated online social therapy (MOST) are achieving a range of positive clinical and functional outcomes, while emerging technologies like virtual reality have strong evidence in anxiety disorder, and accumulating evidence in psychotic conditions. Implementation science frameworks show promise in helping overcome the common challenges faced in real-world adoption and ongoing use. CONCLUSION: The integrated, blended use of digital mental health technologies with face-to-face clinical care has the potential to improve care quality for young people while helping overcome the growing challenges faced by youth mental health service providers.


Assuntos
Serviços de Saúde Mental , Transtornos Psicóticos , Humanos , Adolescente , Saúde Mental , Transtornos Psicóticos/terapia , Transtornos de Ansiedade
10.
Basic Res Cardiol ; 117(1): 31, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35727392

RESUMO

Remote ischaemic preconditioning (RIPC) using transient limb ischaemia failed to improve clinical outcomes following cardiac surgery and the reasons for this remain unclear. In the ERIC-GTN study, we evaluated whether concomitant nitrate therapy abrogated RIPC cardioprotection. We also undertook a post-hoc analysis of the ERICCA study, to investigate a potential negative interaction between RIPC and nitrates on clinical outcomes following cardiac surgery. In ERIC-GTN, 185 patients undergoing cardiac surgery were randomized to: (1) Control (no RIPC or nitrates); (2) RIPC alone; (3); Nitrates alone; and (4) RIPC + Nitrates. An intravenous infusion of nitrates (glyceryl trinitrate 1 mg/mL solution) was commenced on arrival at the operating theatre at a rate of 2-5 mL/h to maintain a mean arterial pressure between 60 and 70 mmHg and was stopped when the patient was taken off cardiopulmonary bypass. The primary endpoint was peri-operative myocardial injury (PMI) quantified by a 48-h area-under-the-curve high-sensitivity Troponin-T (48 h-AUC-hs-cTnT). In ERICCA, we analysed data for 1502 patients undergoing cardiac surgery to investigate for a potential negative interaction between RIPC and nitrates on clinical outcomes at 12-months. In ERIC-GTN, RIPC alone reduced 48 h-AUC-hs-cTnT by 37.1%, when compared to control (ratio of AUC 0.629 [95% CI 0.413-0.957], p = 0.031), and this cardioprotective effect was abrogated in the presence of nitrates. Treatment with nitrates alone did not reduce 48 h-AUC-hs-cTnT, when compared to control. In ERICCA there was a negative interaction between nitrate use and RIPC for all-cause and cardiovascular mortality at 12-months, and for risk of peri-operative myocardial infarction. RIPC alone reduced the risk of peri-operative myocardial infarction, compared to control, but no significant effect of RIPC was demonstrated for the other outcomes. When RIPC and nitrates were used together they had an adverse impact in patients undergoing cardiac surgery with the presence of nitrates abrogating RIPC-induced cardioprotection and increasing the risk of mortality at 12-months post-cardiac surgery in patients receiving RIPC.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Precondicionamento Isquêmico Miocárdico , Precondicionamento Isquêmico , Infarto do Miocárdio , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Humanos , Precondicionamento Isquêmico/efeitos adversos , Infarto do Miocárdio/etiologia , Nitratos , Resultado do Tratamento , Troponina T
11.
J Neurol Neurosurg Psychiatry ; 93(2): 158-168, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34353857

RESUMO

BACKGROUND: Therapeutic trials are now underway in genetic forms of frontotemporal dementia (FTD) but clinical outcome measures are limited. The two most commonly used measures, the Clinical Dementia Rating (CDR)+National Alzheimer's Disease Coordinating Center (NACC) Frontotemporal Lobar Degeneration (FTLD) and the FTD Rating Scale (FRS), have yet to be compared in detail in the genetic forms of FTD. METHODS: The CDR+NACC FTLD and FRS were assessed cross-sectionally in 725 consecutively recruited participants from the Genetic FTD Initiative: 457 mutation carriers (77 microtubule-associated protein tau (MAPT), 187 GRN, 193 C9orf72) and 268 family members without mutations (non-carrier control group). 231 mutation carriers (51 MAPT, 92 GRN, 88 C9orf72) and 145 non-carriers had available longitudinal data at a follow-up time point. RESULTS: Cross-sectionally, the mean FRS score was lower in all genetic groups compared with controls: GRN mutation carriers mean 83.4 (SD 27.0), MAPT mutation carriers 78.2 (28.8), C9orf72 mutation carriers 71.0 (34.0), controls 96.2 (7.7), p<0.001 for all comparisons, while the mean CDR+NACC FTLD Sum of Boxes was significantly higher in all genetic groups: GRN mutation carriers mean 2.6 (5.2), MAPT mutation carriers 3.2 (5.6), C9orf72 mutation carriers 4.2 (6.2), controls 0.2 (0.6), p<0.001 for all comparisons. Mean FRS score decreased and CDR+NACC FTLD Sum of Boxes increased with increasing disease severity within each individual genetic group. FRS and CDR+NACC FTLD Sum of Boxes scores were strongly negatively correlated across all mutation carriers (rs=-0.77, p<0.001) and within each genetic group (rs=-0.67 to -0.81, p<0.001 in each group). Nonetheless, discrepancies in disease staging were seen between the scales, and with each scale and clinician-judged symptomatic status. Longitudinally, annualised change in both FRS and CDR+NACC FTLD Sum of Boxes scores initially increased with disease severity level before decreasing in those with the most severe disease: controls -0.1 (6.0) for FRS, -0.1 (0.4) for CDR+NACC FTLD Sum of Boxes, asymptomatic mutation carriers -0.5 (8.2), 0.2 (0.9), prodromal disease -2.3 (9.9), 0.6 (2.7), mild disease -10.2 (18.6), 3.0 (4.1), moderate disease -9.6 (16.6), 4.4 (4.0), severe disease -2.7 (8.3), 1.7 (3.3). Sample sizes were calculated for a trial of prodromal mutation carriers: over 180 participants per arm would be needed to detect a moderate sized effect (30%) for both outcome measures, with sample sizes lower for the FRS. CONCLUSIONS: Both the FRS and CDR+NACC FTLD measure disease severity in genetic FTD mutation carriers throughout the timeline of their disease, although the FRS may be preferable as an outcome measure. However, neither address a number of key symptoms in the FTD spectrum, for example, motor and neuropsychiatric deficits, which future scales will need to incorporate.


Assuntos
Demência Frontotemporal/diagnóstico , Testes de Estado Mental e Demência , Proteína C9orf72 , Estudos de Coortes , Estudos Transversais , Progressão da Doença , Humanos , Mutação , Proteínas tau
12.
Brain ; 144(10): 2964-2970, 2021 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-33892504

RESUMO

In vitro studies of autosomal dominant Alzheimer's disease implicate longer amyloid-ß peptides in disease pathogenesis; however, less is known about the behaviour of these mutations in vivo. In this cross-sectional cohort study, we used liquid chromatography-tandem mass spectrometry to analyse 66 plasma samples from individuals who were at risk of inheriting a mutation or were symptomatic. We tested for differences in amyloid-ß (Aß)42:38, Aß42:40 and Aß38:40 ratios between presenilin 1 (PSEN1) and amyloid precursor protein (APP) carriers. We examined the relationship between plasma and in vitro models of amyloid-ß processing and tested for associations with parental age at onset. Thirty-nine participants were mutation carriers (28 PSEN1 and 11 APP). Age- and sex-adjusted models showed marked differences in plasma amyloid-ß between genotypes: higher Aß42:38 in PSEN1 versus APP (P < 0.001) and non-carriers (P < 0.001); higher Aß38:40 in APP versus PSEN1 (P < 0.001) and non-carriers (P < 0.001); while Aß42:40 was higher in both mutation groups compared to non-carriers (both P < 0.001). Amyloid-ß profiles were reasonably consistent in plasma and cell lines. Within the PSEN1 group, models demonstrated associations between Aß42:38, Aß42:40 and Aß38:40 ratios and parental age at onset. In vivo differences in amyloid-ß processing between PSEN1 and APP carriers provide insights into disease pathophysiology, which can inform therapy development.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/genética , Presenilina-1/sangue , Presenilina-1/genética , Adulto , Doença de Alzheimer/diagnóstico , Biomarcadores/sangue , Estudos de Coortes , Estudos Transversais , Feminino , Genótipo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade
13.
Brain ; 144(2): 434-449, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33479777

RESUMO

Alzheimer's disease has a preclinical stage when cerebral amyloid-ß deposition occurs before symptoms emerge, and when amyloid-ß-targeted therapies may have maximum benefits. Existing amyloid-ß status measurement techniques, including amyloid PET and CSF testing, are difficult to deploy at scale, so blood biomarkers are increasingly considered for screening. We compared three different blood-based techniques-liquid chromatography-mass spectrometry measures of plasma amyloid-ß, and single molecule array (Simoa) measures of plasma amyloid-ß and phospho-tau181-to detect cortical 18F-florbetapir amyloid PET positivity (defined as a standardized uptake value ratio of >0.61 between a predefined cortical region of interest and eroded subcortical white matter) in dementia-free members of Insight 46, a substudy of the population-based British 1946 birth cohort. We used logistic regression models with blood biomarkers as predictors of amyloid PET status, with or without age, sex and APOE ε4 carrier status as covariates. We generated receiver operating characteristics curves and quantified areas under the curves to compare the concordance of the different blood tests with amyloid PET. We determined blood test cut-off points using Youden's index, then estimated numbers needed to screen to obtain 100 amyloid PET-positive individuals. Of the 502 individuals assessed, 441 dementia-free individuals with complete data were included; 82 (18.6%) were amyloid PET-positive. The area under the curve for amyloid PET status using a base model comprising age, sex and APOE ε4 carrier status was 0.695 (95% confidence interval: 0.628-0.762). The two best-performing Simoa plasma biomarkers were amyloid-ß42/40 (0.620; 0.548-0.691) and phospho-tau181 (0.707; 0.646-0.768), but neither outperformed the base model. Mass spectrometry plasma measures performed significantly better than any other measure (amyloid-ß1-42/1-40: 0.817; 0.770-0.864 and amyloid-ß composite: 0.820; 0.775-0.866). At a cut-off point of 0.095, mass spectrometry measures of amyloid-ß1-42/1-40 detected amyloid PET positivity with 86.6% sensitivity and 71.9% specificity. Without screening, to obtain 100 PET-positive individuals from a population with similar amyloid PET positivity prevalence to Insight 46, 543 PET scans would need to be performed. Screening using age, sex and APOE ε4 status would require 940 individuals, of whom 266 would proceed to scan. Using mass spectrometry amyloid-ß1-42/1-40 alone would reduce these numbers to 623 individuals and 243 individuals, respectively. Across a theoretical range of amyloid PET positivity prevalence of 10-50%, mass spectrometry measures of amyloid-ß1-42/1-40 would consistently reduce the numbers proceeding to scans, with greater cost savings demonstrated at lower prevalence.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/sangue , Fragmentos de Peptídeos/sangue , Idoso , Doença de Alzheimer/metabolismo , Biomarcadores/sangue , Diagnóstico Precoce , Feminino , Testes Hematológicos/métodos , Humanos , Masculino , Estudos Prospectivos , Sensibilidade e Especificidade
14.
J Pediatr Gastroenterol Nutr ; 75(5): 635-642, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36070552

RESUMO

OBJECTIVES: Cystic fibrosis liver disease (CFLD) begins early in life. Symptoms may be vague, mild, or nonexistent. Progressive liver injury may be associated with decrements in patient health before liver disease is clinically apparent. We examined Health-Related Quality of Life (HRQOL) in children enrolled in a multi-center study of CFLD to determine the impact of early CFLD on general and disease-specific QOL. METHODS: Ultrasound (US) patterns of normal (NL), heterogeneous (HTG), homogeneous (HMG), or nodular (NOD) were assigned in a prospective manner to predict those at risk for advanced CFLD. Parents were informed of results. We assessed parent/child-reported (age ≥5 years) HRQOL by PedsQL 4.0 Generic Core and CF Questionnaire-revised (CFQ-R) prior to US and annually. HRQOL scores were compared by US pattern at baseline (prior to US), between baseline and 1 year and at 5 years. Multivariate analysis of variance (MANOVA) with Hotelling-Lawley trace tested for differences among US groups. RESULTS: Prior to US, among 515 participants and their parents there was no evidence that HTG or NOD US was associated with reduced PedsQL/CFQ-R at baseline. Parents of NOD reported no change in PedsQL/CFQ-R over the next year. Child-report PedsQL/CFQ-R (95 NL, 20 NOD) showed improvement between baseline and year 5 for many scales, including Physical Function. Parents of HMG children reported improved CFQ-R scores related to weight. CONCLUSIONS: Early undiagnosed or pre-symptomatic liver disease had no impact on generic or disease-specific HRQoL, and HRQoL was remarkably stable in children with CF regardless of liver involvement.


Assuntos
Fibrose Cística , Hepatopatias , Humanos , Pré-Escolar , Qualidade de Vida , Estudos Prospectivos , Nível de Saúde , Fibrose Cística/complicações , Fibrose Cística/diagnóstico por imagem , Inquéritos e Questionários , Hepatopatias/etiologia , Hepatopatias/complicações
15.
J Clin Densitom ; 25(2): 189-197, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34404568

RESUMO

INTRODUCTION: Visceral adipose tissue (VAT) is a hypothesized driver of chronic disease. Dual-energy X-ray absorptiometry (DXA) potentially offers a lower cost and more available alternative compared to gold-standard magnetic resonance imaging (MRI) for quantification of abdominal fat sub-compartments, VAT and subcutaneous adipose tissue (SAT). We sought to validate VAT and SAT area (cm2) from historical DXA scans against MRI. METHODOLOGY: Participants (n = 69) from the Women's Health Initiative (WHI) completed a 3 T MRI scan and a whole body DXA scan (Hologic QDR2000 or QDR4500; 2004-2005). A subset of 43 participants were scanned on both DXA devices. DXA-derived VAT and SAT at the 4th lumbar vertebrae (5 cm wide) were analyzed using APEX software (v4.0, Hologic, Inc., Marlborough, MA). MRI VAT and SAT areas for the corresponding DXA region of interest were quantified using sliceOmatic software (v5.0, Tomovision, Magog, Canada). Pearson correlations between MRI and DXA-derived VAT and SAT were computed, and a Bland-Altman analysis was performed. RESULTS: Participants were primarily non-Hispanic white (86%) with a mean age of 70.51 ± 5.79 years and a mean BMI of 27.33 ± 5.40 kg/m2. Correlations between MRI and DXA measured VAT and SAT were 0.90 and 0.92, respectively (p ≤ 0.001). Bland-Altman plots showed that DXA-VAT slightly overestimated VAT on the QDR4500 (-3.31 cm2); this bias was greater in the smaller subset measured on the older DXA model (QDR2000; -30.71 cm2). The overestimation of DXA-SAT was large (-85.16 to -118.66 cm2), but differences were relatively uniform for the QDR4500. CONCLUSIONS: New software applied to historic Hologic DXA scans provide estimates of VAT and SAT that are well-correlated with criterion MRI among postmenopausal women.


Assuntos
Gordura Intra-Abdominal , Pós-Menopausa , Absorciometria de Fóton/métodos , Tecido Adiposo , Idoso , Feminino , Humanos , Gordura Intra-Abdominal/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Gordura Subcutânea
16.
Intern Med J ; 52(6): 952-958, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33646630

RESUMO

BACKGROUND: Diabetes distress, self-efficacy and health literacy are associated with diabetes self-management and health outcomes. Measures of coping styles and their impact on diabetes self-management and diabetes-related distress might add value in identifying those at risk of poorer health outcomes. Current evidence of associations between psychological flexibility/inflexibility and diabetes-related health outcomes is limited. AIMS: To measure associations of psychological flexibility, self-efficacy and health literacy with diabetes distress and glycated haemoglobin (HbA1c) in adults with type 1 diabetes. METHODS: We surveyed 105 adults with type 1 diabetes attending a tertiary diabetes outpatient clinic (mean age 27 ± 7.1 years; 53% men; duration of diabetes 12.6 ± 8.5 years; HbA1c 72 ± 22 mmol/mol, 8.7 ± 2.0%; 34% using insulin pumps). We assessed psychological flexibility, self-efficacy, health literacy and diabetes distress. Regression models explored the relative contributions of different factors to diabetes distress and HbA1c. RESULTS: The majority of health literacy scores were in the low-risk range. Those with greater psychological flexibility had higher self-efficacy (r = 0.34; P < 0.01) and reported less diabetes distress (r = -0.54; P < 0.001). In multiple regression analyses, psychological flexibility and self-efficacy accounted for 36% of the variance in distress score (P < 0.001). Shorter duration of diabetes (P < 0.001) and greater psychological flexibility (P < 0.01) correlated with lower HbA1c. A 10-point (one standard deviation) higher psychological flexibility score corresponded to a 0.5% lower HbA1c. CONCLUSIONS: Greater psychological flexibility was associated with less diabetes distress and lower HbA1c. The psychological flexibility construct might inform alternative interventional approaches aiming to improve well-being and glycaemic control.


Assuntos
Diabetes Mellitus Tipo 1 , Letramento em Saúde , Adulto , Diabetes Mellitus Tipo 1/complicações , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Autoeficácia , Estresse Psicológico , Inquéritos e Questionários , Adulto Jovem
17.
BMC Pediatr ; 22(1): 54, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-35062907

RESUMO

BACKGROUND: Poor child growth and development outcomes stem from complex relationships encompassing biological, behavioral, social, and environmental conditions. However, there is a dearth of research on integrated approaches targeting these interwoven factors. The Grandi Byen study seeks to fill this research gap through a three-arm longitudinal randomized controlled trial which will evaluate the impact of an integrated nutrition, responsive parenting, and WASH (water, sanitation and hygiene) intervention on holistic child growth and development. METHODS: We will recruit 600 mother-infant dyads living in Cap-Haitien, Haiti and randomize them equally into one of the following groups: 1) standard well-baby care; 2) nutritional intervention (one egg per day for 6 months); and 3) multicomponent Grandi Byen intervention (responsive parenting, nutrition, WASH + one egg per day for 6 months). Primary outcomes include child growth as well as cognitive, language, motor, and social-emotional development. The study also assesses other indicators of child health (bone maturation, brain growth, diarrheal morbidity and allergies, dietary intake, nutrient biomarkers) along with responsive parenting as mediating factors influencing the primary outcomes. An economic evaluation will assess the feasibility of large-scale implementation of the interventions. DISCUSSION: This study builds on research highlighting the importance of responsive parenting interventions on overall child health, as well as evidence demonstrating that providing an egg daily to infants during the complementary feeding period can prevent stunted growth. The multicomponent Grandi Byen intervention may provide evidence of synergistic or mediating effects of an egg intervention with instruction on psychoeducational parenting and WASH on child growth and development. Grandi Byen presents key innovations with implications for the well-being of children living in poverty globally. TRIAL REGISTRATION: NCT04785352 . Registered March 5, 2021 at https://clinicaltrials.gov/.


Assuntos
Higiene , Poder Familiar , Criança , Desenvolvimento Infantil , Crescimento e Desenvolvimento , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Ensaios Clínicos Controlados Aleatórios como Assunto , Saneamento
18.
Proc Natl Acad Sci U S A ; 116(22): 11020-11027, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31072935

RESUMO

Understanding the mode of action of drugs is a challenge with conventional methods in clinical trials. Here, we aimed to explore whether simvastatin effects on brain atrophy and disability in secondary progressive multiple sclerosis (SPMS) are mediated by reducing cholesterol or are independent of cholesterol. We applied structural equation models to the MS-STAT trial in which 140 patients with SPMS were randomized to receive placebo or simvastatin. At baseline, after 1 and 2 years, patients underwent brain magnetic resonance imaging; their cognitive and physical disability were assessed on the block design test and Expanded Disability Status Scale (EDSS), and serum total cholesterol levels were measured. We calculated the percentage brain volume change (brain atrophy). We compared two models to select the most likely one: a cholesterol-dependent model with a cholesterol-independent model. The cholesterol-independent model was the most likely option. When we deconstructed the total treatment effect into indirect effects, which were mediated by brain atrophy, and direct effects, simvastatin had a direct effect (independent of serum cholesterol) on both the EDSS, which explained 69% of the overall treatment effect on EDSS, and brain atrophy, which, in turn, was responsible for 31% of the total treatment effect on EDSS [ß = -0.037; 95% credible interval (CI) = -0.075, -0.010]. This suggests that simvastatin's beneficial effects in MS are independent of its effect on lowering peripheral cholesterol levels, implicating a role for upstream intermediate metabolites of the cholesterol synthesis pathway. Importantly, it demonstrates that computational models can elucidate the causal architecture underlying treatment effects in clinical trials of progressive MS.


Assuntos
Modelos Estatísticos , Esclerose Múltipla Crônica Progressiva , Sinvastatina/uso terapêutico , Adulto , Atrofia , Encéfalo/patologia , Causalidade , Colesterol/sangue , Ensaios Clínicos como Assunto , Progressão da Doença , Humanos , Pessoa de Meia-Idade , Esclerose Múltipla Crônica Progressiva/tratamento farmacológico , Esclerose Múltipla Crônica Progressiva/patologia
19.
Am J Hum Biol ; 33(2): e23467, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33249679

RESUMO

OBJECTIVE: Nutrition during pregnancy is an important modifiable determinant of fetal growth and development. This pilot study aimed to characterize the association between fetal anthropometry, fetal brain development, and maternal diet among women in Ecuador using portable ultrasound in resource-limited clinics, including measurements of brain structures not typically imaged in this setting. METHODS: Pregnant women (n = 47) from four resource-limited health centers were surveyed on demographic, socioeconomic, morbidity, and dietary information. Maternal height, weight, and blood pressure were taken. A sonographer took 15 images per participant, including those standardly assessed during the fetal survey and additional brain structures identified as potentially responsive to maternal nutrition, but not part of the standard fetal survey. RESULTS: Mean percentiles for all standard fetal survey measurements generated from WHO Fetal Growth Curves fell below 50%, and negative mean Z scores were found for biparietal diameter (-0.95 ± 1.11) and femur length (-0.22 ± 1.10). Generalized linear modeling adjusting for gestational age and other covariates showed frequency of seafood consumption was positively associated with fetal biparietal diameter Z score (P = 0.005), beans and legumes positively associated with femur length (P = 0.006), and a negative association was found for soda consumption and fetal head circumference (P = 0.013). CONCLUSIONS: This pilot study demonstrated the feasibility of capturing images of nutrition-relevant fetal brain structures not part of the standard fetal survey in resource-limited settings using portable ultrasound. Our study revealed associations between anthropometry, brain structure size, and maternal diet demonstrating potential for prenatal nutrition research using ultrasound in the field.


Assuntos
Encéfalo/diagnóstico por imagem , Dieta/estatística & dados numéricos , Desenvolvimento Fetal , Feto/diagnóstico por imagem , Fenômenos Fisiológicos da Nutrição Materna , Ultrassonografia Pré-Natal , Adulto , Equador , Estudos de Viabilidade , Feminino , Humanos , Projetos Piloto , Gravidez , Adulto Jovem
20.
BMC Geriatr ; 21(1): 475, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34465287

RESUMO

BACKGROUND: Grip strength is an indicator of physical function with potential predictive value for health in ageing populations. We assessed whether trends in grip strength from midlife predicted later-life brain health and cognition. METHODS: 446 participants in an ongoing British birth cohort study, the National Survey of Health and Development (NSHD), had their maximum grip strength measured at ages 53, 60-64, and 69, and subsequently underwent neuroimaging as part of a neuroscience sub-study, referred to as "Insight 46", at age 69-71. A group-based trajectory model identified latent groups of individuals in the whole NSHD cohort with below- or above-average grip strength over time, plus a reference group. Group assignment, plus standardised grip strength levels and change from midlife were each related to measures of whole-brain volume (WBV) and white matter hyperintensity volume (WMHV), plus several cognitive tests. Models were adjusted for sex, body size, head size (where appropriate), sociodemographics, and behavioural and vascular risk factors. RESULTS: Lower grip strength from midlife was associated with smaller WBV and lower matrix reasoning scores at age 69-71, with findings consistent between analysis of individual time points and analysis of trajectory groups. There was little evidence of an association between grip strength and other cognitive test scores. Although greater declines in grip strength showed a weak association with higher WMHV at age 69-71, trends in the opposite direction were seen at individual time points with higher grip strength at ages 60-64, and 69 associated with higher WMHV. CONCLUSIONS: This study provides preliminary evidence that maximum grip strength may have value in predicting brain health. Future work should assess to what extent age-related declines in grip strength from midlife reflect concurrent changes in brain structure.


Assuntos
Encéfalo , Cognição , Idoso , Envelhecimento , Encéfalo/diagnóstico por imagem , Estudos de Coortes , Força da Mão , Humanos
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