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1.
Artigo em Inglês | MEDLINE | ID: mdl-38912813

RESUMO

CONTEXT: Early age at menarche (AAM) is a risk factor for type 2 diabetes later in life, but the pathogenic pathways that confer increased risk remain unknown. OBJECTIVE: We examined the associations between AAM and inflammatory and glucose metabolism biomarkers among U.S. adult women who were free of diabetes. METHODS: Using the National Health and Nutrition Examination Survey (NHANES) 1999-2018, 19,228 women over 20 years old who were free of self-reported cancer and diabetes were included in this cross-sectional analysis. AAM was the self-reported age at first menstruation. CRP, fasting glucose, fasting insulin, and ferritin levels were measured as biomarkers of inflammation and glucose metabolism in adult blood samples using latex-enhanced nephelometry, enzymatic, and immunoassay methods. Multiple linear regression was used to relate AAM to the biomarkers. RESULTS: The median age at the time of blood sample collection was 44 years (IQR, 33-62). After age adjustment, there was an association between a lower AAM and higher CRP (P-trend=0.006); fasting glucose (P-trend<0.0001); fasting insulin (P-trend <0.0001); and ferritin (p-trend<0.0001). These remained significant after additional adjustment for demographic, reproductive, lifestyle, and adiposity variables, except for ferritin. Smoking modified the effect of AAM on CRP (p-interaction = 0.014), fasting insulin (p-interaction <0.001), and fasting glucose (p-interaction<0.001). In stratified analysis, the observed associations became more pronounced in non-smokers, while they were attenuated to non-significance in active smokers. CONCLUSION: Earlier age at menarche is associated with an unfavorable inflammatory and glucose metabolic biomarker profile in a nationally representative sample of adult women free of diabetes, especially among non-smokers.

2.
J Magn Reson Imaging ; 59(3): 1070-1073, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37246446

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is a leading cause of end-stage liver disease. NAFLD diagnosis and follow-up relies on a combination of clinical data, liver imaging, and/or liver biopsy. However, intersite imaging differences impede diagnostic consistency and reduce the repeatability of the multisite clinical trials necessary to develop effective treatments. PURPOSE/HYPOTHESIS: The goal of this pilot study was to harmonize commercially available 3 T magnetic resonance imaging (MRI) measurements of liver fat and stiffness in human participants across academic sites and MRI vendors. STUDY TYPE: Cohort. SUBJECTS: Four community-dwelling adults with obesity. FIELD STRENGTH/SEQUENCE: 1.5 and 3 T, multiecho 3D imaging, PRESS, and GRE. ASSESSMENT: Harmonized proton density fat fraction (PDFF) and magnetic resonance spectroscopy (MRS) protocols were used to quantify the FF of synthetic phantoms and human participants with obesity using standard acquisition parameters at four sites that had four different 3 T MRI instruments. In addition, a harmonized magnetic resonance elastography (MRE) protocol was used to quantify liver stiffness among participants at two different sites at 1.5 and 3 T field strengths. Data were sent to a single data coordinating site for postprocessing. STATISTICAL TESTS: Linear regression in MATLAB, ICC analyses using SAS 9.4, one-sided 95% confidence intervals for the ICC. RESULTS: PDFF and MRS FF measurements were highly repeatable among sites in both humans and phantoms. MRE measurements of liver stiffness in three individuals at two sites using one 1.5 T and one 3 T instrument showed repeatability that was high although lower than that of MRS and PDFF. CONCLUSIONS: We demonstrated harmonization of PDFF, MRS, and MRE-based quantification of liver fat and stiffness through synthetic phantoms, traveling participants, and standardization of postprocessing analysis. Multisite MRI harmonization could contribute to multisite clinical trials assessing the efficacy of interventions and therapy for NAFLD. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 2.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Adulto , Humanos , Hepatopatia Gordurosa não Alcoólica/patologia , Projetos Piloto , Reprodutibilidade dos Testes , Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Obesidade/patologia
3.
Mech Ageing Dev ; 218: 111898, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38159613

RESUMO

INTRODUCTION: We present the rationale and design of a double-blind placebo-controlled feasibility trial combining intranasal insulin (INI) with semaglutide, a GLP-1 receptor agonist, to improve cognition in older adults with metabolic syndrome (MetS) and mild cognitive impairment (MCI). Since both INI and dulaglutide have beneficial effects on the cerebrovascular disease (CVD), we anticipate that improved CVD will underlie the hypothesized cognitive benefits. METHODS: This 12-months trial will include 80 older adults aged > 60 with MetS and MCI, randomized to 4 groups: INI/oral semaglutide, intranasal placebo/oral semaglutide, INI/oral placebo, and intranasal placebo/oral placebo. Feasibility of combining INI with semaglutide will be tested by examining the ease of use of INI (20IU, twice/day) with semaglutide (14 once daily), adherence, and safety profile are the efficacy of combination therapy on global cognition and neurobiological markers: cerebral blood flow, cerebral glucose utilization, white matter hyperintensities, Alzheimer's related blood biomarkers and expression of insulin signaling proteins measured in brain-derived exosomes. Efficacy will be assessed for the intent-to-treat sample. DISCUSSION: This feasibility study is anticipated to provide the basis for a multi-center large-scale randomized clinical trial (RCT) of the cognitive benefits of the combination of INI with semaglutide in individuals enriched for CVD and at high dementia risk.


Assuntos
Doenças Cardiovasculares , Demência , Diabetes Mellitus Tipo 2 , Peptídeos Semelhantes ao Glucagon , Síndrome Metabólica , Humanos , Idoso , Insulina , Estudos de Viabilidade , Síndrome Metabólica/tratamento farmacológico , Cognição , Hipoglicemiantes/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Método Duplo-Cego
4.
J Alzheimers Dis ; 94(1): 101-113, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37212094

RESUMO

BACKGROUND: Individuals with Alzheimer's disease (AD) often present with coexisting vascular pathology that is expressed to different degrees and can lead to clinical heterogeneity. OBJECTIVE: To examine the utility of unsupervised statistical clustering approaches in identifying neuropsychological (NP) test performance subtypes that closely correlate with carotid intima-media thickness (cIMT) in midlife. METHODS: A hierarchical agglomerative and k-means clustering analysis based on NP scores (standardized for age, sex, and race) was conducted among 1,203 participants (age 48±5.3 years) from the Bogalusa Heart Study. Regression models assessed the association between cIMT ≥50th percentile and NP profiles, and global cognitive score (GCS) tertiles for sensitivity analysis. RESULTS: Three NP profiles were identified: Mixed-low performance [16%, n = 192], scores ≥1 SD below the mean on immediate, delayed free recall, recognition verbal memory, and information processing; Average [59%, n = 704]; and Optimal [26%, n = 307] NP performance. Participants with greater cIMT were more likely to have a Mixed-low profile [OR = 3.10, 95% CI (2.13, 4.53), p < 0.001] compared to Optimal. After adjusting for education and cardiovascular (CV) risks, results remained. The association with GCS tertiles was more attenuated [lowest (34%, n = 407) versus highest (33%, n = 403) tertile: adjusted OR = 1.66, 95% CI (1.07, 2.60), p = 0.024]. CONCLUSION: As early as midlife, individuals with higher subclinical atherosclerosis were more likely to be in the Mixed-low profile, underscoring the potential malignancy of CV risk as related to NP test performance, suggesting that classification approaches may aid in identifying those at risk for AD/vascular dementia spectrum illness.


Assuntos
Doença de Alzheimer , Aterosclerose , Transtornos Cognitivos , Humanos , Espessura Intima-Media Carotídea , Fatores de Risco , Transtornos Cognitivos/psicologia , Estudos Longitudinais , Aterosclerose/complicações , Doença de Alzheimer/complicações
5.
Obesity (Silver Spring) ; 30(9): 1863-1874, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35920161

RESUMO

OBJECTIVE: The 10-year intensive lifestyle intervention (ILI) of the Look AHEAD study left a legacy of relative deficits in cognitive function among participants who entered the clinical trial with obesity or a history of cardiovascular disease. We hypothesized that altered levels of two weight-sensitive proangiogenic cytokines, leptin and vascular endothelial growth factor (VEGF), accounted for this concerning finding. METHODS: Serum leptin and VEGF concentrations were determined in 1,279 Look AHEAD participants at baseline, proximal to cessation of the interventions (Epoch 1), and an average of 4 years later (Epoch 2). Up to four standardized assessments of attention, executive function, and memory were collected during follow-up. Mixed effects models were used to assess relative differences in leptin and VEGF concentrations between intervention groups and whether these accounted for changes in cognitive composite scores. RESULTS: ILI and diabetes support and education differences in VEGF, but not leptin, concentrations varied depending on baseline history of cardiovascular disease and obesity, but neither leptin nor VEGF concentrations accounted for the relative decrements in cognitive function in participants assigned to ILI. CONCLUSIONS: Alterations in two weight-sensitive proangiogenic cytokines did not account for the long-term adverse effects of ILI on cognitive function among adults with diabetes and either obesity or cardiovascular disease.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Doenças Cardiovasculares/complicações , Cognição , Citocinas , Diabetes Mellitus Tipo 2/complicações , Humanos , Estilo de Vida , Obesidade/complicações , Sobrepeso/complicações , Fator A de Crescimento do Endotélio Vascular , Redução de Peso
6.
Hum Brain Mapp ; 42(1): 24-35, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32910516

RESUMO

Declining estrogen levels before, during, and after menopause can affect memory and risk for Alzheimer's disease. Undesirable side effects of hormone variations emphasize a role for hormone therapy (HT) where possible benefits include a delay in the onset of dementia-yet findings are inconsistent. Effects of HT may be mediated by estrogen receptors found throughout the brain. Effects may also depend on lifestyle factors, timing of use, and genetic risk. We studied the impact of self-reported HT use on brain volume in 562 elderly women (71-94 years) with mixed cognitive status while adjusting for aforementioned factors. Covariate-adjusted voxelwise linear regression analyses using a model with 16 predictors showed HT use as positively associated with regional brain volumes, regardless of cognitive status. Examinations of other factors related to menopause, oophorectomy and hysterectomy status independently yielded positive effects on brain volume when added to our model. One interaction term, HTxBMI, out of several examined, revealed significant negative association with overall brain volume, suggesting a greater reduction in brain volume than BMI alone. Our main findings relating HT to regional brain volume were as hypothesized, but some exploratory analyses were not in line with existing hypotheses. Studies suggest lower levels of estrogen resulting from oophorectomy and hysterectomy affect brain volume negatively, and the addition of HT modifies the relation between BMI and brain volume positively. Effects of HT may depend on the age range assessed, motivating studies with a wider age range as well as a randomized design.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/efeitos dos fármacos , Cognição/fisiologia , Terapia de Reposição de Estrogênios , Estrogênios/metabolismo , Estrogênios/farmacologia , Pós-Menopausa/fisiologia , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Histerectomia/efeitos adversos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Ovariectomia/efeitos adversos , Pós-Menopausa/metabolismo
7.
Int J Behav Nutr Phys Act ; 17(1): 108, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32831103

RESUMO

BACKGROUND: High levels of sedentary behavior and low physical activity are associated with poor health, and the cognitive determinants of these behaviors in children and adolescents are not well understood. To address this gap, we developed a novel, non-verbal, computer-based assessment to quantify the degree to which youth prefer to be sedentary relative to physically active in their leisure time. METHODS: The Activity Preference Assessment (APA) uses a forced-choice paradigm to understand implicit decision-making processes when presented with common sedentary and physical activities. The APA bias score ranges from - 100 to + 100, with positive scores indicating a relative preference for sedentary activities, and negative scores representing a preference for physical activities. In 60 children ages 8-17 years, we assessed the validity of this behavioral task against a free-choice play observation, accelerometry-measured activity, anthropometrics and body composition, and cardiorespiratory fitness. We explored neighborhood, family, and individual-level factors that may influence implicit activity preferences. Test-retest reliability was assessed over one week. RESULTS: The majority of children (67%) preferred sedentary relative to physical activities. APA bias scores were positively associated with sedentary time during free-choice play. In girls, bias scores were negatively associated with average daily MVPA. APA bias scores were positively associated with body fat and negatively associated with cardiorespiratory fitness. These findings were independent of age, sex, and race/ethnicity. Neighborhood access to physical activity spaces, the number of people in the home, perceived physical self-competence (e.g., coordination, strength), and self-reported depressive symptoms were associated with activity preferences. The intra-class correlation for test-retest reliability was r = 0.59. CONCLUSIONS: The APA shows promise as a novel tool for quantifying children's relative preference for sedentary versus physical activities. Implicit bias scores from the APA are clinically meaningful, as shown by significant associations with adiposity and cardiorespiratory fitness. Future longitudinal studies should examine the directionality of the association between preferences and health markers, and the degree to which implicit activity preferences are modifiable. Importantly, the task only takes an average of 10 min to complete, highlighting a potential role as an efficient screening tool for the propensity to be sedentary versus physically active. TRIAL REGISTRATION: ClinicalTrials.gov NCT03624582 .


Assuntos
Comportamento do Adolescente , Comportamento Infantil , Tomada de Decisões , Exercício Físico , Atividades de Lazer , Comportamento Sedentário , Inquéritos e Questionários , Acelerometria , Adiposidade , Adolescente , Composição Corporal , Aptidão Cardiorrespiratória , Criança , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Obesidade , Psicometria , Reprodutibilidade dos Testes , Características de Residência , Autorrelato
8.
J Gerontol A Biol Sci Med Sci ; 73(11): 1560-1567, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-29846553

RESUMO

Background: Lifestyle interventions to reduce weight and increase activity may preserve higher-order cognitive abilities in overweight/obese adults with type 2 diabetes (T2D). Methods: Adults (N = 5,084) with T2D who enrolled in a randomized clinical trial of a 10-year intensive lifestyle intervention (ILI) compared with diabetes support and education were queried at baseline and repeatedly during follow-up for complaints about difficulties in memory, problem-solving, and decision-making abilities. Results: For those without baseline complaints, assignment to ILI was associated with lower odds that complaints would emerge during follow-up for decision-making ability (odds ratio [OR]=0.851, [95% CI, 0.748,0.967], p=0.014), and, among individuals who were not obese, lower odds that complaints would emerge about problem-solving ability (OR=0.694 [0.510,0.946]). No cognitive benefits from ILI were seen for individuals with baseline complaints about cognitive abilities. ILI may have exacerbated the severity of complaints about problem-solving ability during follow-up among individuals with baseline complaints and cardiovascular disease (OR=2.949 [1.378,6.311]). Conclusions: A long-term multidomain ILI may reduce the likelihood that complaints about difficulties in higher-order cognitive abilities will emerge in T2D adults without pre-existing complaints. Among those with pre-existing complaints, the ILI did not prevent increases in complaint severity.


Assuntos
Tomada de Decisões , Diabetes Mellitus Tipo 2/terapia , Estilo de Vida , Memória , Resolução de Problemas , Restrição Calórica , Cognição , Diabetes Mellitus Tipo 2/epidemiologia , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Inquéritos e Questionários , Programas de Redução de Peso
9.
Nat Commun ; 8: 13624, 2017 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-28098162

RESUMO

The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal volume, four of them novel. Of the novel loci, three lie within genes (ASTN2, DPP4 and MAST4) and one is found 200 kb upstream of SHH. A hippocampal subfield analysis shows that a locus within the MSRB3 gene shows evidence of a localized effect along the dentate gyrus, subiculum, CA1 and fissure. Further, we show that genetic variants associated with decreased hippocampal volume are also associated with increased risk for Alzheimer's disease (rg=-0.155). Our findings suggest novel biological pathways through which human genetic variation influences hippocampal volume and risk for neuropsychiatric illness.


Assuntos
Hipocampo/crescimento & desenvolvimento , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Criança , Estudos de Coortes , Dipeptidil Peptidase 4/genética , Feminino , Loci Gênicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Glicoproteínas/genética , Humanos , Masculino , Metionina Sulfóxido Redutases/genética , Proteínas Associadas aos Microtúbulos/genética , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Tamanho do Órgão , Proteínas Serina-Treonina Quinases/genética , Adulto Jovem
10.
Medicine (Baltimore) ; 96(50): e9233, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29390353

RESUMO

The mechanisms linking short stature with an increase in cardiovascular and cerebrovascular disease risk remain elusive. This study tested the hypothesis that significant associations are present between height and blood pressure in a representative sample of the US adult population.Participants were 12,988 men and women from a multiethnic sample (age ≥ 18 years) evaluated in the 1999 to 2006 National Health and Nutrition Examination Survey who were not taking antihypertensive medications and who had complete height, weight, % body fat, and systolic and diastolic arterial blood pressure (SBP and DBP) measurements; mean arterial blood pressure and pulse pressure (MBP and PP) were calculated. Multiple regression models for men and women were developed with each blood pressure as dependent variable and height, age, race/ethnicity, body mass index, % body fat, socioeconomic status, activity level, and smoking history as potential independent variables.Greater height was associated with significantly lower SBP and PP, and higher DBP (all P < .001) in combined race/ethnic-sex group models beginning in the 4th decade. Predicted blood pressure differences between people who are short and tall increased thereafter with greater age except for MBP. Socioeconomic status, activity level, and smoking history did not consistently contribute to blood pressure prediction models.Height-associated blood pressure effects were present in US adults who appeared in the 4th decade and increased in magnitude with greater age thereafter. These observations, in the largest and most diverse population sample evaluated to date, provide support for postulated mechanisms linking adult stature with cardiovascular and cerebrovascular disease risk.


Assuntos
Pressão Sanguínea/fisiologia , Estatura , Adulto , Fatores Etários , Antropometria , Diástole , Etnicidade , Feminino , Humanos , Masculino , Inquéritos Nutricionais , Fatores de Risco , Sístole , Estados Unidos
11.
Nat Neurosci ; 19(12): 1569-1582, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27694991

RESUMO

Intracranial volume reflects the maximally attained brain size during development, and remains stable with loss of tissue in late life. It is highly heritable, but the underlying genes remain largely undetermined. In a genome-wide association study of 32,438 adults, we discovered five previously unknown loci for intracranial volume and confirmed two known signals. Four of the loci were also associated with adult human stature, but these remained associated with intracranial volume after adjusting for height. We found a high genetic correlation with child head circumference (ρgenetic = 0.748), which indicates a similar genetic background and allowed us to identify four additional loci through meta-analysis (Ncombined = 37,345). Variants for intracranial volume were also related to childhood and adult cognitive function, and Parkinson's disease, and were enriched near genes involved in growth pathways, including PI3K-AKT signaling. These findings identify the biological underpinnings of intracranial volume and their link to physiological and pathological traits.


Assuntos
Cognição/fisiologia , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único/genética , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Loci Gênicos/genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Proteína Oncogênica v-akt/genética , Doença de Parkinson/genética , Fenótipo , Fosfatidilinositol 3-Quinases/genética , População Branca
12.
J Alzheimers Dis ; 44(1): 319-28, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25213770

RESUMO

Cerebral white matter lesions (WMLs) are considered a reflection of cerebral and systemic small vessel disease (SVD), and are associated with reductions in brain volume. Like the brain, the kidney is also sensitive to factors that affect vasculature. Glomerular dysfunction due to renal vascular damage can be measured with different biochemical parameters, such as creatinine or cystatin C, although cystatin C is considered to be more accurate than creatinine in the elderly. The purpose of the study was to determine whether manifestations of SVD in the kidney can predict SVD-based damage to the brain. We examined the relationship between glomerular dysfunction as a measure of SVD on WMLs, gray matter (GM) volume, and cognition in 735 cognitively normal participants from the Cardiovascular Health Study Cognition Study. The multivariate analyses controlled for demographic characteristics, hypertension, heart disease, diabetes, Apolipoprotein 4 allele, C reactive protein, lipids, physical activity, smoking, and body mass index (BMI). Elevated cystatin C levels were associated with lower neuropsychological test scores, the presence of MRI-identified brain infarcts, the severity of WMLs, and GM atrophy five years later. In adjusted models, GM volume was significantly associated with cystatin-C only until BMI and severity of WMLs were added to the model, meaning that the effect of SVD on GM volume is mediated by these two variables. These findings suggest that age-related SVD is a process that leads to altered brain structure, and creates a vulnerability state for cognitive decline.


Assuntos
Encéfalo/patologia , Transtornos Cerebrovasculares/patologia , Imageamento por Ressonância Magnética , Doenças Vasculares Periféricas/patologia , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Modelos Logísticos , Masculino , Testes Neuropsicológicos , Valor Preditivo dos Testes , Estudos Retrospectivos , Substância Branca/patologia
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