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BACKGROUND: Cardiovascular disease (CVD), including elevated blood pressure (BP), is known to promote Alzheimer's disease (AD) risk. Although brain amyloid load is a recognized hallmark of pre-symptomatic AD, its relationship to increased BP is less known. The objective of this study was to examine the relationship of BP to brain estimates of amyloid-ß (Aß) and standard uptake ratio (SUVr). We hypothesized that increased BP is associated with increased SUVr. METHODS: Using data from the Alzheimer's Disease Neuroimaging Initiative (ADNI), we stratified BP according to the Seventh Joint National Committee (JNC) on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure Classification (JNC VII). Florbetapir (AV-45) SUVr was derived from the averaged frontal, anterior cingulate, precuneus, and parietal cortex relative to the cerebellum. A linear mixed-effects model enabled the elucidation of amyloid SUVr relationships to BP. The model discounted the effects of demographics, biologics, and diagnosis at baseline within APOE genotype groups. The least squares means procedure was used to estimate the fixed-effect means. All analyses were performed using the Statistical Analysis System (SAS). RESULTS: In non-É4 carrier MCI subjects, escalating JNC categories of BP was associated with increasing mean SUVr using JNC-4 as a reference point (low-normal (JNC1) p = 0.018; normal (JNC-1) p = 0.039; JNC-2 p = 0.018 and JNC-3 p = 0.04). A significantly higher brain SUVr was associated with increasing BP despite adjustment for demographics and biological variables in non-É4 carriers but not in É4-carriers. This observation supports the view that CVD risk may promote increased brain amyloid load, and potentially, amyloid-mediated cognitive decline. CONCLUSION: Increasing levels of JNC classification of BP is dynamically associated with significant changes in brain amyloid burden in non-É4 carriers but not in É4-carrier MCI subjects. Though not statistically significant, amyloid burden tended to decrease with increasing BP in É4 homozygote, perhaps motivated by increased vascular resistance and the need for higher brain perfusion pressure.
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Enfermedad de Alzheimer , Enfermedades Cardiovasculares , Disfunción Cognitiva , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/psicología , Presión Sanguínea , Tomografía de Emisión de Positrones/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Disfunción Cognitiva/psicología , Péptidos beta-Amiloides , Neuroimagen , Amiloide/metabolismoRESUMEN
Between 2018 and 2019, multiple clinical trials ended earlier than planned, resulting in calls to improve communication with and support for participants and their study partners ("dyads"). The multidisciplinary Participant Follow-Up Improvement in Research Studies and Trials (Participant FIRST) Work Group met throughout 2021. Its goals were to identify best practices for communicating with and supporting dyads affected by early trial stoppage. The Participant FIRST Work Group identified 17 key recommendations spanning the pre-trial, mid-trial, and post-trial periods. These focus on prospectively allocating sufficient resources for orderly closeout; developing dyad-centered communication plans; helping dyads build and maintain support networks; and, if a trial stops, informing dyads rapidly. Participants and study partners invest time, effort, and hope in their research participation. The research community should take intentional steps toward better communicating with and supporting participants when clinical trials end early. The Participant FIRST recommendations are a practical guide for embarking on that journey.
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Comunicación , HumanosRESUMEN
PurposeTelephone disclosure of genetic test results can improve access to services. To date, studies of its impact have focused on return of Mendelian risk information, principally hereditary cancer syndromes.MethodsIn a multisite trial of Alzheimer disease genetic risk disclosure, asymptomatic adults were randomized to receive test results in person or via telephone. Primary analyses examined patient outcomes 12 months after disclosure.ResultsData from 257 participants showed that telephone disclosure occurred 7.4 days sooner and was 30% shorter, on average, than in-person disclosure (both P < 0.001). Anxiety and depression scores were well below cutoffs for clinical concern across protocols. Comparing telephone and in-person disclosure protocols, 99% confidence intervals of mean differences were within noninferiority margins on scales assessing anxiety, depression, and test-related distress, but inconclusive about positive impact. No differences were observed on measures of recall and subjective impact. Subanalyses supported noninferiority on all outcomes among apolipoprotein E (APOE) É4-negative participants. Subanalyses were inconclusive for APOE É4-positive participants, although mean anxiety and depression scores were still well below cutoffs for clinical concern.ConclusionTelephone disclosure of APOE results and risk for Alzheimer disease is generally safe and helps providers meet demands for services, even when results identify an increased risk for disease.
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Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/genética , Revelación , Asesoramiento Genético , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Teléfono , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo , Factores de Riesgo , Adulto JovenRESUMEN
BACKGROUND: It is increasingly evident that high blood pressure can promote reduction in global and regional brain volumes. While these effects may preferentially affect the hippocampus, reports are inconsistent. METHODS: Using data from the Alzheimer's Disease Neuroimaging Initiative (ADNI), we examined the relationships of hippocampal volume to pulse pressure (PPR) and systolic (SBP) and diastolic (DBP) blood pressure according to apolipoprotein (APOE) É4 positivity and cognitive status. The ADNI data included 1,308 participants: Alzheimer disease (AD = 237), late mild cognitive impairment (LMCI = 454), early mild cognitive impairment (EMCI = 254), and cognitively normal (CN = 365), with up to 24 months of follow-up. RESULTS: Higher quartiles of PPR were significantly associated with lower hippocampal volumes (Q1 vs. Q4, p = 0.034) in the CN and AD groups, but with increasing hippocampal volume (Q1, p = 0.008; Q2, p = 0.020; Q3, p = 0.017; Q4 = reference) in the MCI groups. In adjusted stratified analyses among non-APOE É4 carriers, the effects in the CN (Q1 vs. Q4, p = 0.006) and EMCI groups (Q1, p = 0.002; Q2, p = 0.013; Q3, p = 0.002; Q4 = reference) remained statistically significant. Also, higher DBP was significantly associated with higher hippocampal volume (p = 0.002) while higher SBP was significantly associated with decreasing hippocampal volume in the EMCI group (p = 0.015). CONCLUSION: Changes in PPR, SBP, and DBP differentially influenced hippocampal volumes depending on the cognitive and APOE genotypic categories.
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Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/psicología , Apolipoproteínas E/genética , Presión Sanguínea , Cognición , Frecuencia Cardíaca , Hipocampo/patología , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Disfunción Cognitiva/genética , Disfunción Cognitiva/patología , Disfunción Cognitiva/psicología , Femenino , Genotipo , Humanos , Imagen por Resonancia Magnética , Masculino , Neuroimagen , Pruebas Neuropsicológicas , Síntomas ProdrómicosRESUMEN
Neuroinflammation and reactive oxygen species are thought to mediate the pathogenesis of Alzheimer's disease (AD), suggesting that mild cognitive impairment (MCI), a prodromal stage of AD, may be driven by similar insults. Several studies document that hypoxia-inducible factor 1 (HIF-1) is neuroprotective in the setting of neuronal insults, since this transcription factor drives the expression of critical genes that diminish neuronal cell death. HIF-1 facilitates glycolysis and glucose metabolism, thus helping to generate reductive equivalents of NADH/NADPH that counter oxidative stress. HIF-1 also improves cerebral blood flow which opposes the toxicity of hypoxia. Increased HIF-1 activity and/or expression of HIF-1 target genes, such as those involved in glycolysis or vascular flow, may be an early adaptation to the oxidative stressors that characterize MCI pathology. The molecular events that constitute this early adaptation are likely neuroprotective, and might mitigate cognitive decline or the onset of full-blown AD. On the other hand, prolonged or overwhelming stressors can convert HIF-1 into an activator of cell death through agents such as Bnip3, an event that is more likely to occur in late MCI or advanced Alzheimer's dementia.
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Disfunción Cognitiva/metabolismo , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/fisiopatología , Animales , Apoptosis , Circulación Cerebrovascular , Disfunción Cognitiva/patología , Disfunción Cognitiva/fisiopatología , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , MemoriaRESUMEN
BACKGROUND: Increasing use of genetic testing raises questions about disclosing secondary findings, including pleiotropic information. OBJECTIVE: To determine the safety and behavioral effect of disclosing modest associations between apolipoprotein E (APOE) genotype and coronary artery disease (CAD) risk during APOE-based genetic risk assessments for Alzheimer disease (AD). DESIGN: Randomized, multicenter equivalence clinical trial. (ClinicalTrials.gov: NCT00462917). SETTING: 4 teaching hospitals. PARTICIPANTS: 257 asymptomatic adults were enrolled, 69% of whom had 1 AD-affected first-degree relative. INTERVENTION: Disclosure of genetic risk information about AD and CAD (AD+CAD) or AD only (AD-only). MEASUREMENTS: Primary outcomes were Beck Anxiety Inventory (BAI) and Center for Epidemiologic Studies Depression Scale (CES-D) scores at 12 months. Secondary outcomes were all measures at 6 weeks and 6 months and test-related distress and health behavior changes at 12 months. RESULTS: At 12 months, mean BAI scores were 3.5 in both the AD-only and AD+CAD groups (difference, 0.0 [95% CI, -1.0 to 1.0]), and mean CES-D scores were 6.4 and 7.1 in the AD-only and AD+CAD groups, respectively (difference, 0.7 [CI, -1.0 to 2.4]). Both confidence bounds fell within the equivalence margin of ±5 points. Among carriers of the APOE ε4 allele, distress was lower in the AD+CAD groups (difference, -4.8 [CI, -8.6 to -1.0]) (P = 0.031 for the interaction between group and APOE genotype). Participants in the AD+CAD groups also reported more health behavior changes, regardless of APOE genotype. LIMITATIONS: Outcomes were self-reported by volunteers without severe anxiety, severe depression, or cognitive problems. Analyses omitted 33 randomly assigned participants. CONCLUSION: Disclosure of pleiotropic information did not increase anxiety or depression and may have decreased distress among persons at increased risk for 2 conditions. Providing risk modification information about CAD improved health behaviors. Findings highlight the potential benefits of disclosure of secondary genetic findings when options exist for decreasing risk. PRIMARY FUNDING SOURCE: National Human Genome Research Institute.
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Enfermedad de Alzheimer/genética , Enfermedad de la Arteria Coronaria/genética , Predisposición Genética a la Enfermedad , Medición de Riesgo , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/psicología , Ansiedad/etiología , Apolipoproteína E4/genética , Enfermedad de la Arteria Coronaria/psicología , Depresión/etiología , Femenino , Genotipo , Conductas Relacionadas con la Salud , Humanos , Masculino , Persona de Mediana Edad , Estrés Psicológico/etiología , Adulto JovenRESUMEN
INTRODUCTION: African-American (AA) individuals have a higher risk for late-onset Alzheimer's disease (LOAD) than Americans of primarily European ancestry (EA). Recently, the largest genome-wide association study in AAs to date confirmed that six of the Alzheimer's disease (AD)-related genetic variants originally discovered in EA cohorts are also risk variants in AA; however, the risk attributable to many of the loci (e.g., APOE, ABCA7) differed substantially from previous studies in EA. There likely are risk variants of higher frequency in AAs that have not been discovered. METHODS: We performed a comprehensive analysis of genetically determined local and global ancestry in AAs with regard to LOAD status. RESULTS: Compared to controls, LOAD cases showed higher levels of African ancestry, both globally and at several LOAD relevant loci, which explained risk for AD beyond global differences. DISCUSSION: Exploratory post hoc analyses highlight regions with greatest differences in ancestry as potential candidate regions for future genetic analyses.
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Enfermedad de Alzheimer/etnología , Enfermedad de Alzheimer/genética , Predisposición Genética a la Enfermedad/genética , Transportadoras de Casetes de Unión a ATP/genética , Negro o Afroamericano/genética , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/epidemiología , Apolipoproteínas E/genética , Distribución de Chi-Cuadrado , Aberraciones Cromosómicas , Estudios de Cohortes , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Polimorfismo de Nucleótido Simple/genética , Lectina 3 Similar a Ig de Unión al Ácido Siálico/genéticaRESUMEN
INTRODUCTION: Conventional multisession genetic counseling is currently recommended when disclosing apolipoprotein E (APOE) genotype for the risk of Alzheimer's disease (AD) in cognitively normal individuals. The objective of this study was to evaluate the safety of brief disclosure protocols for disclosing APOE genotype for the risk of AD. METHODS: A randomized, multicenter noninferiority trial was conducted at four sites. Participants were asymptomatic adults having a first-degree relative with AD. A standard disclosure protocol by genetic counselors (SP-GC) was compared with condensed protocols, with disclosures by genetic counselors (CP-GC) and by physicians (CP-MD). Preplanned co-primary outcomes were anxiety and depression scales 12 months after disclosure. RESULTS: Three hundred and forty-three adults (mean age 58.3, range 33-86 years, 71% female, 23% African American) were randomly assigned to the SP-GC protocol (n = 115), CP-GC protocol (n = 116), or CP-MD protocol (n = 112). Mean postdisclosure scores on all outcomes were well below cut-offs for clinical concern across protocols. Comparing CP-GC with SP-GC, the 97.5% upper confidence limits at 12 months after disclosure on co-primary outcomes of anxiety and depression ranged from a difference of 1.2 to 2.0 in means (all P < .001 on noninferiority tests), establishing noninferiority for condensed protocols. Results were similar between European Americans and African Americans. CONCLUSIONS: These data support the safety of condensed protocols for APOE disclosure for those free of severe anxiety or depression who are actively seeking such information.
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Enfermedad de Alzheimer/genética , Apolipoproteínas E/genética , Revelación , Asesoramiento Genético , Predisposición Genética a la Enfermedad , Adulto , Negro o Afroamericano/genética , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/psicología , Ansiedad , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Población Blanca/genética , Adulto JovenRESUMEN
IMPORTANCE: Genetic variants associated with susceptibility to late-onset Alzheimer disease are known for individuals of European ancestry, but whether the same or different variants account for the genetic risk of Alzheimer disease in African American individuals is unknown. Identification of disease-associated variants helps identify targets for genetic testing, prevention, and treatment. OBJECTIVE: To identify genetic loci associated with late-onset Alzheimer disease in African Americans. DESIGN, SETTING, AND PARTICIPANTS: The Alzheimer Disease Genetics Consortium (ADGC) assembled multiple data sets representing a total of 5896 African Americans (1968 case participants, 3928 control participants) 60 years or older that were collected between 1989 and 2011 at multiple sites. The association of Alzheimer disease with genotyped and imputed single-nucleotide polymorphisms (SNPs) was assessed in case-control and in family-based data sets. Results from individual data sets were combined to perform an inverse variance-weighted meta-analysis, first with genome-wide analyses and subsequently with gene-based tests for previously reported loci. MAIN OUTCOMES AND MEASURES: Presence of Alzheimer disease according to standardized criteria. RESULTS: Genome-wide significance in fully adjusted models (sex, age, APOE genotype, population stratification) was observed for a SNP in ABCA7 (rs115550680, allele = G; frequency, 0.09 cases and 0.06 controls; odds ratio [OR], 1.79 [95% CI, 1.47-2.12]; P = 2.2 × 10(-9)), which is in linkage disequilibrium with SNPs previously associated with Alzheimer disease in Europeans (0.8 < D' < 0.9). The effect size for the SNP in ABCA7 was comparable with that of the APOE ϵ4-determining SNP rs429358 (allele = C; frequency, 0.30 cases and 0.18 controls; OR, 2.31 [95% CI, 2.19-2.42]; P = 5.5 × 10(-47)). Several loci previously associated with Alzheimer disease but not reaching significance in genome-wide analyses were replicated in gene-based analyses accounting for linkage disequilibrium between markers and correcting for number of tests performed per gene (CR1, BIN1, EPHA1, CD33; 0.0005 < empirical P < .001). CONCLUSIONS AND RELEVANCE: In this meta-analysis of data from African American participants, Alzheimer disease was significantly associated with variants in ABCA7 and with other genes that have been associated with Alzheimer disease in individuals of European ancestry. Replication and functional validation of this finding is needed before this information is used in clinical settings.
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Transportadoras de Casetes de Unión a ATP/genética , Enfermedad de Alzheimer/etnología , Enfermedad de Alzheimer/genética , Apolipoproteína E4/genética , Negro o Afroamericano/genética , Estudio de Asociación del Genoma Completo , Edad de Inicio , Anciano , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Variación Genética , Genotipo , Humanos , Desequilibrio de Ligamiento , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , RiesgoRESUMEN
Implications for practice and research: Clinicians should have heightened awareness and inquire about feelings of loneliness when providing care for older adults. More studies are needed to further elucidate gender-based differences on the relationship between loneliness and mortality.
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Accumulating evidence suggests that α-synuclein plays a role in the pathophysiology of Alzheimer's disease (AD). This study examined whether α-synuclein level in cerebrospinal fluid (CSF) was associated with cognitive functioning among older adults. We also explored whether this relationship was mediated by proinflammatory cytokines TNF-α and IL-6, along with sIL-6R and vascular endothelial growth factor (VEGF). Using a cross-sectional Alzheimer's Disease Neuroimaging Initiative (ADNI; Nâ =â 148) sample, we examined the relationship between α-synuclein and participants' performance on Mini-Mental State Examination (MMSE) and Alzheimer's Disease Assessment Scale Cognitive Subscale (ADAS-Cog 13) at baseline. Mediation analyses were utilized, adjusting for age, education, APOEe4, and Geriatric Depression Scale scores. All biological markers were measured in CSF. Participants in the current sample were 58.3% males, 41.7% females, and Caucasian (95.5%); their average education and age were 15.5 (standard deviation [SD]â =â 2.97) and 74.4 (SDâ =â 7.51) years, respectively. Higher accumulation of α-synuclein was associated with poorer MMSE scores (ßâ =â -0.41, standard error [SE]â =â 1.54, pâ <â .001). This relationship appeared to be mediated by VEGF (ßâ =â 0.27, SEâ =â 2.15, pâ =â .025) and IL-6r (ßâ =â 0.22, SEâ =â 1.66, pâ <â .026). In addition, α-synuclein was associated with poorer performance on the ADAS-Cog 13 (ßâ =â 0.34, pâ =â .005) and mediated by VEGF (ßâ =â -0.19, SEâ =â 4.13, pâ =â .025) after adjusting for age, education, APOEe4, and depressive symptoms. α-Synuclein may serve as an additional biomarker for determining poor cognitive functioning. VEGF and IL-6 soluble receptors were significant mediators of the relationship between α-synuclein and cognitive functioning. If confirmed in prospective analyses, these findings can further inform the pathologic cascade and early diagnosis of AD.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Masculino , Femenino , Humanos , Anciano , Enfermedad de Alzheimer/diagnóstico , alfa-Sinucleína/líquido cefalorraquídeo , Factor A de Crecimiento Endotelial Vascular , Disfunción Cognitiva/diagnóstico , Estudios Transversales , Interleucina-6 , Estudios Prospectivos , Cognición , Biomarcadores/líquido cefalorraquídeo , Inflamación , Pruebas NeuropsicológicasRESUMEN
BACKGROUND: Understanding the factors driving recruitment and enrollment of African Americans (AA)s in clinical translational research will assure that underrepresented populations benefit from scientific progress and new developments in the diagnosis and treatment of Alzheimer's disease and related disorders. While transportation is pivotal to volunteers' ability to participate in research, its contribution to enrollment in exercise studies on AD is yet to be elucidated. Thus, this research focuses on identifying factors that influence the recruitment and enrollment of African Americans in biomedical studies and determining whether the availability of transportation motivates participation in time-demanding exercise studies on AD. METHODS: We analyzed recruitment data collected from 567 volunteers ages 55 and older screened through various recruitment sources and considered for enrollment in our exercise and memory study. To determine whether transportation influenced the enrollment of African Americans (AA)s in biomedical studies, multiple logistic regression analysis was performed to identify significant factors that drive enrollment. Furthermore, the association of race and demographic factors on the availability of transportation was assessed. RESULTS: Demographic factors, age at screening, education, gender, and cognitive scores were not significantly different among those enrolled compared to control (not-enrolled). In the relationship of enrollment to transportation, enrolled participants were more likely to have access to transportation (79.12%) than not-enrolled participants who had less access to transportation (71.6%); however, the association was not statistically significant. However, race differentially influenced the likelihood of enrollment, with elderly AAs being significantly less likely to have transportation (p = 0.020) than the Whites but more likely than "others" to have transportation. CONCLUSION: Our findings suggest that access to transportation may be a key factor motivating enrollment in an exercise and memory study in a predominantly AA sample. Notably, AAs in our sample were less likely to have transportation than Whites. Other demographic factors and cognitive scores did not significantly influence enrollment in our sample. A larger sample and more detailed assessment of transportation are needed to further discern the role of transportation in clinical trials.
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Negro o Afroamericano , Ensayos Clínicos como Asunto , Participación del Paciente , Transporte de Pacientes , Blanco , Anciano , Humanos , Escolaridad , Accesibilidad a los Servicios de Salud , Persona de Mediana Edad , Memoria , Ejercicio FísicoRESUMEN
An efficient approach to certain types of biomedical research requires a scale that precludes involvement of all critical contributors in all aspects of experimental design, execution, and as well as writing of most, if not all, derived works. Guarantors of both the integrity of the data and of its subsequent analyses are required. When separate groups are responsible for each of these activities, each should be readily identifiable both in the primary publication and in all subsequent citations. We describe the publication policy of the Alzheimer Disease Neuroimaging Initiative (ADNI), its origins and its acceptance by the editorial and scientific communities.
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Edición/normas , AutoriaRESUMEN
BACKGROUND: Magnitudes, geographic and racial variation in trends in coronary heart disease (CHD) mortality within the US require updating for health services and health disparities research. Therefore the aim of this study is to present data on these trends through 2007. METHODS: Data for CHD were analyzed using the US mortality files for 1999-2007 obtained from the US Centers for Disease Control and Prevention. Age-adjusted annual death rates were computed for non-Hispanic African Americans (AA) and European Americans (EA) aged 35-84 years. The direct method was used to standardize rates by age, using the 2000 US standard population. Joinpoint regression models were used to evaluate trends, expressed as annual percent change (APC). RESULTS: For both AA men and women the magnitude in CHD mortality is higher compared to EA men and women, respectively. Between 1999 and 2007 the rate declined both in AA and in EA of both sexes in every geographic division; however, relative declines varied. For example, among men, relative average annual declines ranged from 3.2% to 4.7% in AA and from 4.4% to 5.5% in EA among geographic divisions. In women, rates declined more in later years of the decade and in women over 54 years. In 2007, age-adjusted death rate per 100,000 for CHD ranged from 93 in EA women in New England to 345 in AA men in the East North Central division. In EA, areas near the Ohio and lower Mississippi Rivers had above average rates. Disparities in trends by urbanization level were also found. For AA in the East North Central division, the APC was similar in large central metro (-4.2), large fringe metro (-4.3), medium metro urbanization strata (-4.4), and small metro (-3.9). APC was somewhat higher in the micropolitan/non-metro (-5.3), and especially the non-core/non-metro (-6.5). For EA in the East South Central division, the APC was higher in large central metro (-5.3), large fringe metro (-4.3) and medium metro urbanization strata (-5.1) than in small metro (-3.8), micropolitan/non-metro (-4.0), and non-core/non-metro (-3.3) urbanization strata. CONCLUSIONS: Between 1999 and 2007, the level and rate of decline in CHD mortality displayed persistent disparities. Declines were greater in EA than AA racial groups. Rates were greater in the Ohio and Mississippi River than other geographic regions.
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Negro o Afroamericano/estadística & datos numéricos , Enfermedad Coronaria/etnología , Enfermedad Coronaria/mortalidad , Disparidades en el Estado de Salud , Población Blanca/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Geografía Médica , Humanos , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND AND PURPOSE: Magnitude, geographic, and ethnic variation in trends in stroke within the United States require updating for health services and health disparities research. METHODS: Data for stroke were analyzed from the US mortality files for 1999 to 2007. Age-adjusted death rates were computed for non-Hispanic African Americans and European Americans aged ≥45 years. RESULTS: Between 1999 and 2007, the age-adjusted death rate per 100,000 for stroke declined both in African Americans and in European Americans of both genders. Among African American females, European American females, and European American males, rates declined by at least 2% annually in every division. Among African American males, rates declined little in the East and West South Central divisions where disparities in trends by urbanization level were found. CONCLUSIONS: Between 1999 and 2007, the rate of decline in stroke mortality varied by geographic region and ethnic group.
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Negro o Afroamericano/etnología , Accidente Cerebrovascular/etnología , Accidente Cerebrovascular/mortalidad , Población Blanca/etnología , Etnicidad/etnología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Estados Unidos/epidemiologíaRESUMEN
Low levels of both high density lipoprotein cholesterol (HDL) and cognitive function are associated with increased mortality risk. HDL plays an important role in brain metabolism. We test the hypotheses that the relative protective effect of high HDL level as related to mortality is greater in persons with impaired cognitive function than in others. Data were analyzed from a longitudinal mortality follow-up study of 4911 American men and women aged 60 years and over examined in 1988-1994 followed an average 8.5 yr. Measurements at baseline included HDL, a short index of cognitive function (SICF), socio-demographics, health status, and self-reported leisure-time physical activity. In proportional hazards regression analysis, no significant interaction of HDL with cognitive function was found (p = 0.08); there was a significant age-SICF interaction. After stratifying by age and adjusting for confounding by multiple variables, independent associations of HDL and SICF score with survival were strongest among the oldest persons. Consistent with its association with HDL, cognitive function and survival, controlling in addition for physical activity reduced the associations. In a nationwide cohort of older Americans, analyses demonstrated a lower risk of death independent of confounders among those high HDL and SICF scores, strongest among the oldest persons.
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HDL-Colesterol/sangre , Cognición , Anciano , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Modelos de Riesgos Proporcionales , Análisis de SupervivenciaRESUMEN
Genetic susceptibility testing for common diseases is expanding, but little is known about race group differences in test perceptions. The purpose of this study was to examine differences between African Americans and Whites in knowledge, attitudes, and motivations regarding genetic susceptibility testing for Alzheimer's disease (AD). Before enrolling in an AD genetic testing research trial, 313 first-degree relatives of AD patients (20% African American; 71% female; mean age = 58 years) were surveyed regarding: (1) knowledge about genetics and AD risk; (2) concerns about developing AD; and (3) reasons for seeking testing. In comparison to Whites, African Americans were less knowledgeable about genetics and AD risk (p < .01) and less concerned about developing AD (p < .05), with lower levels of perceived disease risk (p = .04). The results suggest that African Americans and Whites differ notably in their knowledge, beliefs, and attitudes regarding genetic testing for AD. Additional research with more representative samples is needed to better understand these differences.
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Enfermedad de Alzheimer/diagnóstico , Población Negra , Pruebas Genéticas/estadística & datos numéricos , Conocimientos, Actitudes y Práctica en Salud , Población Blanca , Adulto , Enfermedad de Alzheimer/genética , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
The ubiquitin proteasome system (UPS) and FOXOs transcription factors play a pivotal role in cellular clearance and minimizing the accumulation of Aß in neurodegeneration (ND). In African Americans (AAs) with mild cognitive impairment (MCI), the role of components of UPS and FOXOs; and whether they are amenable to exercise effects is unknown. We hypothesized that exercise can enhance cellular clearance systems during aging and ND by increasing expressions of FBXO32 and FOXO1. To test this hypothesis, we used TaqMan gene expression analysis in peripheral blood (PB) to investigate the component of UPS and FOXOs; and provide mechanistic insight at baseline, during exercise, and in both genders. At baseline, levels of FBXO32 were higher in women than in men. In our attempt to discern gender-specific exercise-related changes, we observed that levels of FBXO32 increased in men but not in women. Similarly, levels of FOXO1 increased in men only. These data suggest that a graded dose of FBXO32 and FOXO1 may be beneficial when PB cells carrying FBXO32 and FOXO1 summon into the brain in response to Alzheimer's disease (AD) perturbation (docking station PB cells). Our observation is consistent with emerging studies that exercise allows the trafficking of blood factors. Given the significance of FBXO32 and FOXO1 to ND and associated muscle integrity, our findings may explain, at least in part, the benefits of exercise on memory, associated gait, and balance perturbation acknowledged to herald the emergence of MCI.
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OBJECTIVE: This study evaluated human Blood Oxygen Level-Dependent (BOLD) responses in primary and higher-order olfactory regions of older adults, using odor memory and odor identification tasks. The goal was to determine which olfactory and memory regions of interest are more strongly engaged in older populations comparing these two odor training tasks. METHODS: Twelve adults 55-75 years old (75% females) without intranasal or major neurological disorders performed repetitive odor memory and identification tasks using a 3-tesla magnetic resonance scanner. Odors were presented intermittently at 10-second bursts separated by 20-second intervals of odorless air. Paired t-tests were used to compare differences in the degree of activation between odor identification and odor memory tasks within individuals. An FDR cluster-level correction of p<0.05 was used for multiplicity of tests (with a cluster-defining threshold set at p<0.01 and 10 voxels). RESULTS: Odor identification compared to memory (ie, odor identification > odor memory) contrasts had several areas of significant activation, including many of the classical olfactory brain regions as well as the hippocampus. The opposite contrast (odor memory > odor identification) included the piriform cortex, though this was not significant. Both tasks equally activated the piriform cortex, and thus when the two tasks are compared to each other this area of activation appears to be either absent (OI > OM) or only weakly observed (OM > OI). CONCLUSION: These findings from a predominantly African American sample suggest that odor identification tasks may be more potent than memory tasks in targeted olfactory engagement in older populations. Furthermore, repetitive odor identification significantly engaged the hippocampus - a region relevant to Alzheimer's disease - more significantly than did the odor memory task. If validated in larger studies, this result could have important implications in the design of olfactory training paradigms.
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BACKGROUND: DNA methylation at CpG sites is a vital epigenetic modification of the human genome affecting gene expression, and potentially, health outcomes. However, evidence is just budding on the effects of aerobic exercise-induced adaptation on DNA methylation in older mild cognitively impaired (MCI) elderly African American (AAs). Therefore, we examined the effects of a 6-month aerobic exercise-intervention on genome-wide DNA methylation in elderly AA MCI volunteers. DESIGN: Elderly AA volunteers confirmed MCI assigned into a 6-month program of aerobic exercise (eleven participants) underwent a 40-min supervised-training 3-times/week and controls (eight participants) performed stretch training. Participants had maximal oxygen consumption (VO2max) test and Genome-wide methylation levels at CpG sites using the Infinium HumanMethylation450 BeadChip assay at baseline and after a 6-month exercise program. We computed false discovery rates (FDR) using Sidak to account for multiplicity of tests and performed quantitative real-time polymerase chain-reaction (qRT-PCR) to confirm the effects of DNA methylations on expression levels of the top 5 genes among the aerobic participants. CpG sites identified from aerobic-exercise participants were similarly analyzed by the stretch group to quantify the effects of exercise-induced methylation changes among the group of stretch participants. RESULTS: Eleven MCI participants (aerobic: 73% females; mean age 72.3 ± 6.6 years) and eight MCI participants (stretch: 75% female; mean age 70.6 ± 6.7 years) completed the training. Aerobic exercise-training was associated with increases in VO2max and with global hypo- and hypermethylation changes. The most notable finding was CpG hypomethylation within the body of the VPS52 gene (P = 5.4 × 10-26), a Golgi-associated protein, involved in intracellular protein trafficking including amyloid precursor protein. qRT-PCR confirmed a nearly twofold increased expression of VPS52. Other top findings with FDR q-value < 10-5, include hypomethylations of SCARB1 (8.8 × 10-25), ARTN (6.1 × 10-25), NR1H2 (2.1 × 10-18) and PPP2R5D (9.8 × 10-18). CONCLUSION: We conclude that genome-wide DNA methylation patterns is associated with exercise training-induced methylation changes. Identification of methylation changes around genes previously shown to interact with amyloid biology, intracellular protein trafficking, and lipoprotein regulations provide further support to the likely protective effect of exercise in MCI. Future studies in larger samples are needed to confirm our findings.