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1.
J Alzheimers Dis ; 96(4): 1767-1780, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38007645

RESUMO

BACKGROUND: Alzheimer's disease and related dementias (ADRD) involve biological processes that begin years to decades before onset of clinical symptoms. The plasma proteome can offer insight into brain aging and risk of incident dementia among cognitively healthy adults. OBJECTIVE: To identify biomarkers and biological pathways associated with neuroimaging measures and incident dementia in two large community-based cohorts by applying a correlation-based network analysis to the plasma proteome. METHODS: Weighted co-expression network analysis of 1,305 plasma proteins identified four modules of co-expressed proteins, which were related to MRI brain volumes and risk of incident dementia over a median 20-year follow-up in Framingham Heart Study (FHS) Offspring cohort participants (n = 1,861). Analyses were replicated in the Cardiovascular Health Study (CHS) (n = 2,117, mean 6-year follow-up). RESULTS: Two proteomic modules, one related to protein clearance and synaptic maintenance (M2) and a second to inflammation (M4), were associated with total brain volume in FHS (M2: p = 0.014; M4: p = 4.2×10-5). These modules were not significantly associated with hippocampal volume, white matter hyperintensities, or incident all-cause or AD dementia. Associations with TCBV did not replicate in CHS, an older cohort with a greater burden of comorbidities. CONCLUSIONS: Proteome networks implicate an early role for biological pathways involving inflammation and synaptic function in preclinical brain atrophy, with implications for clinical dementia.


Assuntos
Doença de Alzheimer , Demência , Humanos , Demência/diagnóstico por imagem , Proteoma , Proteômica , Encéfalo/diagnóstico por imagem , Envelhecimento , Biomarcadores , Imageamento por Ressonância Magnética , Inflamação
2.
medRxiv ; 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37662354

RESUMO

Background: The Dietary Inflammatory Index (DII), has been specifically designed to capture the inflammatory content of diet and has shown association with neurodegenerative disease related outcomes. But literature is limited on the role of diet-driven inflammation measured by the DII on incident all-cause dementia and Alzheimer's disease dementia (AD). Objective: We evaluated whether higher DII scores were associated with increased incidence of all-cause dementia and AD over 22.3 years of follow-up in the community-based Framingham Heart Study (FHS) Offspring cohort. Design Setting and Participants: Observational longitudinal study in the FHS Offspring cohort. Dementia surveillance for present study: until 2020. Data were analyzed from December 2020 to June 2022. Participants completed a validated 126-item food frequency questionnaires (FFQ), administered at FHS examination cycle 7 (1998-2001) and examination cycle 5 (1991-1995), and/or 6 (1995-1998). Individuals aged <60 years, with prevalent dementia, no dementia follow-up, other relevant neurological diseases, and/or no FFQ data were excluded. Exposure: A DII score (based on the published method by Shivappa et al. 2014) was created based on previous studies linking individual dietary factors to six inflammatory markers (i.e. C-reactive protein, interleukin (IL)-1ß, IL-4, IL-6, IL-10, and tumor necrosis factor-alpha), consisting of 36 components. A cumulative DII score was calculated by averaging across a maximum of three FFQs. Main outcomes and measures: Incident all-cause dementia and AD. Results: We included 1487 participants (mean±SD, age in years 69 ± 6; 53·2% women; 31·6% college graduates]). 246 participants developed all-cause dementia (including AD n=187) over a median follow up time of 13·1 years. Higher DII scores were associated with an increased incidence of all-cause dementia and AD following adjustment for age and sex (Hazard ratio (HR) 1·16, 95% confidence interval (CI) 1·07 to 1·25, p<.001; HR 1·16, 95% CI 1·06 to 1·26, p=.001). The relationships remained after additional adjustment for demographic, lifestyle, and clinical covariates (HR 1·21, 95% CI 1·10 to 1·33, p<0.001; HR1·20, 95% CI1·07 to 1·35, p=.001). Conclusion and relevance: Higher DII scores were associated with a higher risk of incident all-cause dementia and AD. Although these promising findings need to be replicated and further validated, our results suggest that diets which correlate with low DII scores may prevent late-life dementia.

3.
Microbiome ; 11(1): 131, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37312147

RESUMO

BACKGROUND: Characterization of microbial activity is essential to the understanding of the basic biology of microbial communities, as the function of a microbiome is defined by its biochemically active ("viable") community members. Current sequence-based technologies can rarely differentiate microbial activity, due to their inability to distinguish live and dead sourced DNA. As a result, our understanding of microbial community structures and the potential mechanisms of transmission between humans and our surrounding environments remains incomplete. As a potential solution, 16S rRNA transcript-based amplicon sequencing (16S-RNA-seq) has been proposed as a reliable methodology to characterize the active components of a microbiome, but its efficacy has not been evaluated systematically. Here, we present our work to benchmark RNA-based amplicon sequencing for activity assessment in synthetic and environmentally sourced microbial communities. RESULTS: In synthetic mixtures of living and heat-killed Escherichia coli and Streptococcus sanguinis, 16S-RNA-seq successfully reconstructed the active compositions of the communities. However, in the realistic environmental samples, no significant compositional differences were observed in RNA ("actively transcribed - active") vs. DNA ("whole" communities) spiked with E. coli controls, suggesting that this methodology is not appropriate for activity assessment in complex communities. The results were slightly different when validated in environmental samples of similar origins (i.e., from Boston subway systems), where samples were differentiated both by environment type as well as by library type, though compositional dissimilarities between DNA and RNA samples remained low (Bray-Curtis distance median: 0.34-0.49). To improve the interpretation of 16S-RNA-seq results, we compared our results with previous studies and found that 16S-RNA-seq suggests taxon-wise viability trends (i.e., specific taxa are universally more or less likely to be viable compared to others) in samples of similar origins. CONCLUSIONS: This study provides a comprehensive evaluation of 16S-RNA-seq for viability assessment in synthetic and complex microbial communities. The results found that while 16S-RNA-seq was able to semi-quantify microbial viability in relatively simple communities, it only suggests a taxon-dependent "relative" viability in realistic communities.  Video Abstract.


Assuntos
Escherichia coli , Microbiota , Humanos , Escherichia coli/genética , RNA Ribossômico 16S/genética , Biblioteca Gênica , Temperatura Alta , Microbiota/genética
4.
Sci Rep ; 13(1): 5786, 2023 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-37031215

RESUMO

The drivers of sexual dimorphism in heart failure phenotypes are currently poorly understood. Divergent phenotypes may result from differences in heritability and genetic versus environmental influences on the interplay of cardiac structure and function. To assess sex-specific heritability and genetic versus environmental contributions to variation and inter-relations between echocardiography traits in a large community-based cohort. We studied Framingham Heart Study participants of Offspring Cohort examination 8 (2005-2008) and Third Generation Cohort examination 1 (2002-2005). Five cardiac traits and six functional traits were measured using standardized echocardiography. Sequential Oligogenic Linkage Analysis Routines (SOLAR) software was used to perform singular and bivariate quantitative trait linkage analysis. In our study of 5674 participants (age 49 ± 15 years; 54% women), heritability for all traits was significant for both men and women. There were no significant differences in traits between men and women. Within inter-trait correlations, there were two genetic, and four environmental trait pairs with sex-based differences. Within both significant genetic trait pairs, men had a positive relation, and women had no significant relation. We observed significant sex-based differences in inter-trait genetic and environmental correlations between cardiac structure and function. These findings highlight potential pathways of sex-based divergent heart failure phenotypes.


Assuntos
Insuficiência Cardíaca , Característica Quantitativa Herdável , Masculino , Feminino , Humanos , Caracteres Sexuais , Fenótipo , Variação Biológica da População , Ecocardiografia , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/genética , Variação Genética
5.
Alzheimers Dement ; 19(2): 621-631, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35522830

RESUMO

INTRODUCTION: We investigated cross-sectional associations between the Dietary Inflammatory Index (DII) and measures of brain volume and cerebral small vessel disease among participants of the Framingham Heart Study Offspring cohort. METHODS: A total of 1897 participants (mean ± standard deviation, age 62±9) completed Food Frequency Questionnaires and brain magnetic resonance imaging (MRI). RESULTS: Higher (pro-inflammatory) DII scores, averaged across a maximum of three time points, were associated with smaller total brain volume (beta ± standard error: -0.16 ± 0.03; P < .0001) after adjustment for demographic, clinical, and lifestyle covariates. In addition, higher DII scores were associated with smaller total gray matter volume (-0.08 ± 0.03; P = .003) and larger lateral ventricular volume (0.04 ± 0.02; P = .03). No associations were observed with other brain MRI measures. DISCUSSION: Our findings showed associations between higher DII scores and global brain MRI measures. As we are one of the first groups to report on the associations between higher DII scores and brain volume, replication is needed to confirm our findings.


Assuntos
Envelhecimento , Encéfalo , Humanos , Pessoa de Meia-Idade , Idoso , Estudos Transversais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Inflamação
6.
Alzheimers Dement (Amst) ; 14(1): e12298, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35356487

RESUMO

Introduction: The clinical translation of biofluid markers for dementia requires validation in diverse cohorts. The study goal was to evaluate if blood biomarkers reflecting diverse pathophysiological processes predict disease progression in Mexican American adults. Methods: Mexican American adults (n = 745), 50 years of age and older, completed annual assessments over a mean of 4 years. Serum collected at baseline was assayed for total tau, neurofilament light (NFL), ubiquitin carboxyl-terminal hydrolase LI, glial fibrillary acidic protein (GFAP), soluble cluster of differentiation 14 (sCD14), and chitinase-3-like protein 1 (YKL-40). Results: Higher GFAP and NFL were associated with global cognitive decline. Only GFAP was associated with increased incident dementia risk (hazard ratio: 1.611 (95% confidence interval: 1.204-2.155)) and inclusion of additional biomarkers did not improve model fit. Discussion: Among a panel of six blood biomarkers previously associated with neurodegenerative disease, only GFAP predicted incident dementia in our cohort. The findings suggest that blood GFAP levels may aid dementia-risk prediction among Mexican American adults.

7.
Alzheimers Dement (N Y) ; 7(1): e12164, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33860071

RESUMO

INTRODUCTION: The study evaluated if blood markers reflecting diverse biological pathways differentiate clinical diagnostic groups among Hispanic and non-Hispanic White adults. METHODS: Within Hispanic (n = 1193) and non-Hispanic White (n = 650) participants, serum total tau (t-tau), neurofilament light (NfL), ubiquitin carboxyl-terminal hydrolase LI, glial fibrillary acidic protein (GFAP), soluble cluster of differentiation-14, and chitinase-3-like protein 1 (YKL-40) were quantified. Mixed-effects partial proportional odds ordinal logistic regression and linear mixed-effects models were used to evaluate the association of biomarkers with diagnostic group and cognition, adjusting for age, sex, ethnicity, apolipoprotein E ε4, education, and site. RESULTS: T-tau, NfL, GFAP, and YKL-40 discriminated between diagnostic groups (receiver operating curve: 0.647-0.873). Higher t-tau (odds ratio [OR] = 1.671, 95% confidence interval [CI] = 1.457-1.917, P < .001), NfL (OR = 2.150, 95% CI = 1.819-2.542, P < .001), GFAP (OR = 2.283, 95% CI = 1.915-2.722, P < .001), and YKL-40 (OR = 1.288, 95% CI = 1.125-1.475, P < .001) were associated with increased likelihood of dementia relative to cognitively unimpaired and mild cognitive impairment groups. Higher NfL was associated with poorer global cognition (ß = -0.455, standard error [SE] = 0.083, P < .001), semantic fluency (ß = -0.410, SE = 0.133, P = .002), attention/processing speed (ß = 2.880, SE = 0.801, P < .001), and executive function (ß = 5.965, SE = 2.037, P = .003). Higher GFAP was associated with poorer global cognition (ß = -0.345, SE = 0.092, P = .001), learning (ß = -1.426, SE = 0.359, P < .001), and memory (ß = -0.890, SE = 0.266, P < .001). Higher YKL-40 (ß = -0.537, SE = 0.186, P = .004) was associated with lower memory scores. Interactions with ethnicity were observed for learning (NfL, GFAP, YKL-40), memory (NfL, GFAP), and semantic fluency (NfL; interaction terms P < .008), which were generally no longer significant in a demographically matched subset of Hispanic and non-Hispanic White participants. DISCUSSION: Blood biomarkers of neuronal/axonal and glial injury differentiated between clinical diagnostic groups in a bi-ethnic cohort of Hispanic and non-Hispanic Whites. Our results add to the growing literature indicating that blood biomarkers may be viable tools for detecting neurodegenerative conditions and highlight the importance of validation in diverse cohorts.

9.
BMC Microbiol ; 21(1): 26, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33446094

RESUMO

BACKGROUND: Studies of the gut microbiome are becoming increasingly important. Such studies require stool collections that can be processed or frozen in a timely manner so as not to alter the microbial content. Due to the logistical difficulties of home-based stool collection, there has been a challenge in selecting the appropriate sample collection technique and comparing results from different microbiome studies. Thus, we compared stool collection and two alternative clinic-based fecal microbiome collection techniques, including a newer glove-based collection method. RESULTS: We prospectively enrolled 22 adult men from our prostate cancer screening cohort SABOR (San Antonio Biomarkers of Risk for prostate cancer) in San Antonio, TX, from 8/2018 to 4/2019. A rectal swab and glove tip sample were collected from each participant during a one-time visit to our clinics. A single stool sample was collected at the participant's home. DNA was isolated from the fecal material and 16 s rRNA sequencing of the V1-V2 and V3-V4 regions was performed. We found the gut microbiome to be similar in richness and evenness, noting no differences in alpha diversity among the collection methods. The stool collection method, which remains the gold-standard method for the gut microbiome, proved to have different community composition compared to swab and glove tip techniques (p< 0.001) as measured by Bray-Curtis and unifrac distances. There were no significant differences in between the swab and glove tip samples with regard to beta diversity (p> 0.05). Despite differences between home-based stool and office-based fecal collection methods, we noted that the distance metrics for the three methods cluster by participant indicating within-person similarities. Additionally, no taxa differed among the methods in a Linear Discriminant Analysis Effect Size (LEfSe) analysis comparing all-against-all sampling methods. CONCLUSION: The glove tip method provides similar gut microbiome results as rectal swab and stool microbiome collection techniques. The addition of a new office-based collection technique could help easy and practical implementation of gut microbiome research studies and clinical practice.


Assuntos
Bactérias/classificação , Fezes/microbiologia , Luvas Cirúrgicas/microbiologia , RNA Ribossômico 16S/genética , Reto/microbiologia , Manejo de Espécimes/instrumentação , Idoso , Idoso de 80 Anos ou mais , Bactérias/genética , Bactérias/isolamento & purificação , DNA Bacteriano/genética , DNA Ribossômico/genética , Microbioma Gastrointestinal , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Filogenia , Estudos Prospectivos , Análise de Sequência de DNA/métodos , Manejo de Espécimes/métodos
10.
Circ Heart Fail ; 13(5): e006749, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32408813

RESUMO

BACKGROUND: We used a large-scale, high-throughput DNA aptamer-based discovery proteomic platform to identify circulating biomarkers of cardiac remodeling and incident heart failure (HF) in community-dwelling individuals. METHODS: We evaluated 1895 FHS (Framingham Heart Study) participants (age 55±10 years, 54% women) who underwent proteomic profiling and echocardiography. Plasma levels of 1305 proteins were related to echocardiographic traits and to incident HF using multivariable regression. Statistically significant protein-HF associations were replicated in the HUNT (Nord-Trøndelag Health) study (n=2497, age 63±10 years, 43% women), and results were meta-analyzed. Genetic variants associated with circulating protein levels (pQTLs) were related to echocardiographic traits in the EchoGen (n=30 201) and to incident HF in the CHARGE (n=20 926) consortia. RESULTS: Seventeen proteins associated with echocardiographic traits in cross-sectional analyses (false discovery rate <0.10), and 8 of these proteins had pQTLs associated with echocardiographic traits in EchoGen (P<0.0007). In Cox models adjusted for clinical risk factors, 29 proteins demonstrated associations with incident HF in FHS (174 HF events, mean follow-up 19 [limits, 0.2-23.7] years). In meta-analyses of FHS and HUNT, 6 of these proteins were associated with incident HF (P<3.8×10-5; 3 with higher risk: NT-proBNP [N-terminal proB-type natriuretic peptide], TSP2 [thrombospondin-2], MBL [mannose-binding lectin]; and 3 with lower risk: ErbB1 [epidermal growth factor receptor], GDF-11/8 [growth differentiation factor-11/8], and RGMC [hemojuvelin]). For 5 of the 6 proteins, pQTLs were associated with echocardiographic traits (P<0.0006) in EchoGen, and for RGMC, a protein quantitative trait loci was associated with incident HF (P=0.001). CONCLUSIONS: A large-scale proteomics approach identified new predictors of cardiac remodeling and incident HF. Future studies are warranted to elucidate how biological pathways represented by these proteins may mediate cardiac remodeling and HF risk and to assess if these proteins can improve HF risk prediction.


Assuntos
Aptâmeros de Nucleotídeos , Proteínas Sanguíneas/análise , Ecocardiografia , Variação Genética , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico por imagem , Proteômica , Idoso , Biomarcadores/sangue , Proteínas Sanguíneas/genética , Estudos Transversais , Feminino , Predisposição Genética para Doença , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/genética , Ensaios de Triagem em Larga Escala , Humanos , Incidência , Masculino , Massachusetts/epidemiologia , Pessoa de Meia-Idade , Noruega/epidemiologia , Fenótipo , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Remodelação Ventricular/genética
11.
PLoS One ; 15(4): e0231254, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32275698

RESUMO

BACKGROUND: Heart failure (HF) is a clinical syndrome where diagnostic certainty varies. The prognosis of individuals with some clinical features of HF, but without the fully overt syndrome, is unclear. Therefore, we sought to evaluate their natural history. METHODS AND RESULTS: Between 1990 and 2009, all suspected HF cases in the Framingham Heart Study were adjudicated into 3 groups reflecting varying diagnostic certainty: definite (meeting HF diagnostic criteria; n = 479), possible (meeting HF criteria but with an alternative explanation for findings; n = 135), and probable (insufficient criteria for definite HF; n = 121) HF. Age-and-sex-matched individuals (n = 1112) without HF or cardiovascular disease (CVD) were controls. Using multivariable-adjusted Cox regression, we compared the possible/probable HF groups with controls regarding risk of incident definite HF, coronary heart disease (CHD), other CVD or death; and with definite HF regarding risk of latter three outcomes. During follow-up (mean 8.6 years), ~90% of individuals with possible, probable and definite HF experienced CVD events or died. Compared with controls, those with possible or probable HF experienced higher hazards for definite HF, CHD, other CVD and death (hazards ratios [HR] 1.35-9.31; p<0.05). The possible/probable groups did not differ from the definite HF group for risk of any outcome. Compared with the possible HF group, the probable HF group had a higher propensity for definite HF (HR 1.64, with a higher proportion of ischemic HF) but lower risk of death (HR 0.69). CONCLUSIONS: Individuals meeting partial criteria for HF are at a substantial risk for progression to HF, CVD, and mortality.


Assuntos
Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/patologia , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Insuficiência Cardíaca/epidemiologia , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Fenótipo , Prognóstico , Fatores de Risco , Incerteza
12.
JAMA Cardiol ; 5(5): 549-556, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32159731

RESUMO

Importance: The American Heart Association ideal cardiovascular health (CVH) score is associated with the risk of cardiovascular disease (CVD) and mortality. However, it is unclear whether the number of years spent in ideal CVH is associated with morbidity or with mortality. Objective: To evaluate whether living longer with a higher CVH score in midlife is associated with lower risk of hypertension, diabetes, chronic kidney disease, CVD and its subtypes (coronary heart disease, stroke, congestive heart failure, and peripheral artery disease), or all-cause mortality in later life. Design, Setting, and Participants: This prospective cohort study used data from 1445 participants from 1991 to 2015 who participated in the community-based Framingham Heart Study Offspring investigation conducted in Massachusetts. The CVH scores of participants were assessed at examination cycles 5, 6, and 7 (1991-1995; 1995-1998; and 1998-2001, respectively). Individuals were excluded from analyses of the association between duration of CVH score and outcomes if they had the outcome of interest at the seventh examination. The median follow-up was approximately 16 years. Data were analyzed from April 2018 to October 2019. The CVH score categories were poor for scores 0 to 7, intermediate for scores 8 to 11, and ideal for scores 12 to 14. A composite score was derived based on smoking status, diet, physical activity, resting blood pressure levels, body mass index, fasting blood glucose levels, and total serum cholesterol levels. Main Outcomes and Measures: Number of events and number at risk for each main outcome, including incident hypertension, diabetes, chronic kidney disease, CVD, and all-cause mortality, after the seventh examination. Results: Of 1445 eligible participants, the mean (SD) age was 60 (9) years, and 751 (52%) were women. Number of events/number at risk for each main outcome after the seventh examination were 348/795 for incident hypertension, 104/1304 for diabetes, 198/918 for chronic kidney disease, 210/1285 for CVD, and 300/1445 for all-cause mortality. At the seventh examination, participants mostly had poor (568 [39%]) or intermediate (782 [54%]) CVH scores. For each antecedent (before examination cycle 7) 5-year duration that participants had intermediate or ideal CVH, they were less likely to develop adverse outcomes (hazards ratios of 0.67 [95% CI, 0.56-0.80] for incident hypertension, 0.73 [95% CI, 0.57-0.93] for diabetes, 0.75 [95% CI, 0.63-0.89] for chronic kidney disease, 0.73 [95% CI, 0.63-0.85] for CVD, and 0.86 [95% CI, 0.76-0.97] for all-cause mortality) relative to living the same amount of time in poor CVH (referent group). No effect modification was observed by age or by sex. Conclusions and Relevance: These results suggest that more time spent in better CVH in midlife may have salutary cardiometabolic benefits and may be associated with lower mortality later in life.


Assuntos
Pressão Sanguínea/fisiologia , Doenças Cardiovasculares/epidemiologia , Exercício Físico/fisiologia , Nível de Saúde , Medição de Risco/métodos , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Doenças Cardiovasculares/fisiopatologia , Feminino , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Estados Unidos/epidemiologia
13.
Stat Methods Med Res ; 29(1): 111-121, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30672389

RESUMO

Estimating the precision of a single proportion via a 100(1-α)% confidence interval in the presence of clustered data is an important statistical problem. It is necessary to account for possible over-dispersion, for instance, in animal-based teratology studies with within-litter correlation, epidemiological studies that involve clustered sampling, and clinical trial designs with multiple measurements per subject. Several asymptotic confidence interval methods have been developed, which have been found to have inadequate coverage of the true proportion for small-to-moderate sample sizes. In addition, many of the best-performing of these intervals have not been directly compared with regard to the operational characteristics of coverage probability and empirical length. This study uses Monte Carlo simulations to calculate coverage probabilities and empirical lengths of five existing confidence intervals for clustered data across various true correlations, true probabilities of interest, and sample sizes. In addition, we introduce a new score-based confidence interval method, which we find to have better coverage than existing intervals for small sample sizes under a wide range of scenarios.


Assuntos
Modelos Estatísticos , Análise por Conglomerados , Intervalos de Confiança , Humanos , Método de Monte Carlo , Prevalência , Probabilidade , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Tamanho da Amostra , Irmãos
14.
J Am Soc Echocardiogr ; 33(1): 72-81.e6, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31624026

RESUMO

BACKGROUND: In recent decades, novel echocardiographic measures have constantly emerged. It is still unclear which echocardiographic measures have the most significant prognostic value in the general population. Accordingly, the aim of this study was to compare the prognostic value of a large panel of echocardiographic measures to identify the most promising measures. METHODS: A total of 1,497 Framingham study participants (mean age, 65 years; 55.4% women) who underwent echocardiographic measurements of left ventricular ejection fraction, left ventricular mass index, global longitudinal strain, global circumferential strain, mitral annular plane systolic excursion, mitral E/e' ratio, maximum and minimum left atrial (LA) volume index, LA emptying fraction, and left ventricular longitudinal synchrony were evaluated. These measures were related to the incidence of two composite outcomes: cardiovascular disease (CVD) or death and atrial fibrillation (AF) or congestive heart failure (CHF). RESULTS: On follow-up (mean, 8.3 years), there were 241 CVD events or deaths and 139 AF or CHF events. In multivariate-adjusted Cox models, higher LA emptying fraction was associated with a lower risk (hazard ratios per SD, 0.80 and 0.70 for CVD or death and AF or CHF, respectively; P ≤ .001 for both) while higher minimum LA volume index (hazard ratios per SD, 1.32 and 1.70 for CVD or death and AF or CHF, respectively; P ≤ .001 for both) and maximum LA volume index (hazard ratios per SD, 1.26 and 1.54 for CVD or death and AF or CHF, respectively; P ≤ .002 for both) were associated with a higher risk for both composite outcomes. CONCLUSIONS: In this community-based sample, LA volumes and function were the best echocardiographic predictors of clinical outcomes. Therefore, these values should be considered for inclusion in standard echocardiographic assessments for the purpose of risk stratification.


Assuntos
Doenças Cardiovasculares/diagnóstico , Ecocardiografia/métodos , Medição de Risco/métodos , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Remodelação Ventricular/fisiologia , Idoso , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Prevalência , Prognóstico , Fatores de Tempo , Estados Unidos/epidemiologia
15.
J Am Heart Assoc ; 8(14): e012141, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31303106

RESUMO

Background Excess transmission of pressure pulsatility caused by increased arterial stiffness may incur microcirculatory damage in end organs (target organ damage [TOD] ) and, in turn, elevate risk for cardiovascular disease ( CVD ) events. Methods and Results We related arterial stiffness measures (carotid-femoral pulse wave velocity, mean arterial pressure, central pulse pressure) to the prevalence and incidence of TOD (defined as albuminuria and/or echocardiographic left ventricular hypertrophy) in up to 6203 Framingham Study participants (mean age 50±15 years, 54% women). We then related presence of TOD to incident CVD in multivariable Cox regression models without and with adjustment for arterial stiffness measures. Cross-sectionally, greater arterial stiffness was associated with a higher prevalence of TOD (adjusted odds ratios ranging from 1.23 to 1.54 per SD increment in arterial stiffness measure, P<0.01). Prospectively, increased carotid-femoral pulse wave velocity was associated with incident albuminuria (odds ratio per SD 1.28, 95% CI, 1.02-1.61; P<0.05), whereas higher mean arterial pressure and central pulse pressure were associated with incident left ventricular hypertrophy (odds ratio per SD 1.37 and 1.45, respectively; P<0.01). On follow-up, 297 of 5803 participants experienced a first CVD event. Presence of TOD was associated with a 33% greater hazard of incident CVD (95% CI , 0-77%; P<0.05), which was attenuated upon adjustment for baseline arterial stiffness measures by 5-21%. Conclusions Elevated arterial stiffness is associated with presence of TOD and may partially mediate the relations of TOD with incident CVD . Our observations in a large community-based sample suggest that mitigating arterial stiffness may lower the burden of TOD and, in turn, clinical CVD .


Assuntos
Albuminúria/epidemiologia , Doenças Cardiovasculares/epidemiologia , Hipertrofia Ventricular Esquerda/epidemiologia , Rigidez Vascular/fisiologia , Adulto , Idoso , Angina Pectoris/epidemiologia , Angina Instável/epidemiologia , Pressão Arterial/fisiologia , Doenças Cardiovasculares/mortalidade , Velocidade da Onda de Pulso Carótido-Femoral , Estudos de Coortes , Ecocardiografia , Feminino , Insuficiência Cardíaca/epidemiologia , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Incidência , Claudicação Intermitente/epidemiologia , Ataque Isquêmico Transitório/epidemiologia , Estudos Longitudinais , Masculino , Manometria , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/mortalidade , Estudos Prospectivos , Acidente Vascular Cerebral/epidemiologia
16.
J Clin Endocrinol Metab ; 104(3): 738-752, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30339231

RESUMO

Context: The natural histories of obesity subphenotypes are incompletely delineated. Objectives: To investigate dynamic changes in obesity subphenotypes and associations with outcomes. Design, Setting, Participants, and Measurements: Framingham Offspring Cohort participants (n = 4291) who attended the examination cycles 2 (1979 to 1983) to 7 (1998 to 2001), which included 26,508 participant observations. Obesity subphenotypes [metabolically healthy nonobese (MHNO), metabolically healthy obese (MHO), metabolically unhealthy nonobese (MUNO), and metabolically unhealthy obese (MUO)] were ascertained based on metabolic health (<2 Adult Treatment Panel III criteria). The outcomes were subclinical cardiovascular disease (CVD), incident diseases [diabetes, hypertension, chronic kidney disease (CKD), CVD], and all-cause mortality. Results: At baseline, 4% and 31% of participants exhibited the MHO and MUNO subphenotypes, respectively. Four-year probability of MHO participants becoming MUO was 43% in women and 46% in men. Compared with MHNO, MHO participants had 1.28-fold (95% CI, 0.85 to 1.93) and 1.92-fold (95% CI, 1.38 to 2.68) higher odds of subclinical CVD and coronary artery calcification, respectively; corresponding values for MUNO were 1.95 (1.54 to 2.47) and 1.92 (1.38 to 2.68). During follow-up (median of 14 years), 231 participants developed diabetes, 784 hypertension, 423 CKD, 639 CVD, and 1296 died. Compared with MHNO, MHO conferred higher risks of diabetes [hazard ratio (HR), 4.69; 95% CI, 2.21 to 9.96] and hypertension (HR, 2.21; 95% CI, 1.66 to 2.94). Compared with MUO, MHO conferred lower risks of diabetes (0.21; 0.12 to 0.39), CVD (0.64; 0.43 to 0.95), and CKD (0.44; 0.27 to 0.73), but similar hypertension, cardiovascular mortality, and overall mortality risks. Conclusion: Over time, most MHO participants developed metabolic abnormalities and clinical disease. The MHO subphenotype is a harbinger of future risk.


Assuntos
Síndrome Metabólica/complicações , Obesidade/complicações , Adulto , Aterosclerose/epidemiologia , Aterosclerose/etiologia , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/etiologia , Feminino , Seguimentos , Humanos , Hipertensão/epidemiologia , Hipertensão/etiologia , Masculino , Massachusetts/epidemiologia , Síndrome Metabólica/mortalidade , Pessoa de Meia-Idade , Obesidade/mortalidade , Prevalência , Prognóstico , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/etiologia , Medição de Risco
17.
J Am Heart Assoc ; 7(13)2018 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-29929991

RESUMO

BACKGROUND: Adipokines mediate cardiometabolic risk associated with obesity but their role in the pathogenesis of obesity-associated heart failure remains uncertain. We investigated the associations between circulating adipokine concentrations and echocardiographic measures in a community-based sample. METHODS AND RESULTS: We evaluated 3514 Framingham Heart Study participants (mean age 40 years, 53.8% women) who underwent routine echocardiography and had select circulating adipokines measured, ie, leptin, soluble leptin receptor, fatty acid-binding protein 4, retinol-binding protein 4, fetuin-A, and adiponectin. We used multivariable linear regression, adjusting for known correlates (including weight), to relate adipokine concentrations (independent variables) to the following echocardiographic measures (dependent variables): left ventricular mass index, left atrial diameter in end systole, fractional shortening, and E/e'. In multivariable-adjusted analysis, left ventricular mass index was inversely related to circulating leptin and fatty acid-binding protein 4 concentrations but positively related to retinol-binding protein 4 and leptin receptor levels (P≤0.002 for all). Left atrial end-systolic dimension was inversely related to leptin but positively related to retinol-binding protein 4 concentrations (P≤0.0001). E/e' was inversely related to leptin receptor levels (P=0.0002). We observed effect modification by body weight for select associations (leptin receptor and fatty acid-binding protein 4 with left ventricular mass index, and leptin with left atrial diameter in end systole; P<0.05 for interactions). Fractional shortening was not associated with any of the adipokines. No echocardiographic trait was associated with fetuin-A or adiponectin concentrations. CONCLUSIONS: In our cross-sectional study of a large, young to middle-aged, relatively healthy community-based sample, key indices of subclinical cardiac remodeling were associated with higher or lower circulating concentrations of prohypertrophic and antihypertrophic adipokines in a context-specific manner. These observations may offer insights into the pathogenesis of the cardiomyopathy of obesity.


Assuntos
Adipocinas/sangue , Tecido Adiposo/metabolismo , Cardiomegalia/diagnóstico por imagem , Ecocardiografia Doppler , Coração/diagnóstico por imagem , Tecido Adiposo/fisiopatologia , Adiposidade , Adulto , Doenças Assintomáticas , Biomarcadores/sangue , Cardiomegalia/sangue , Cardiomegalia/fisiopatologia , Estudos Transversais , Feminino , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Remodelação Ventricular
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