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1.
Alzheimers Dement ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38808676

RESUMO

INTRODUCTION: We examined whether hypertension (HTN) was associated with Alzheimer's disease-related biomarkers in cerebrospinal fluid (CSF) and how changes in blood pressure (BP) related to changes in CSF biomarkers over time. METHODS: A longitudinal observation of cognitively healthy normotensive subjects (n = 134, BP < 140/90, with no antihypertensive medication), controlled HTN (n = 36, BP < 140/90, taking antihypertensive medication), and 35 subjects with uncontrolled HTN (BP ≥ 140/90). The follow-up range was 0.5to15.6 years. RESULTS: Total tau (T-tau) and phospho-tau181 (P-tau 181) increased in all but controlled HTN subjects (group×time interaction: p < 0.05 for both), but no significant Aß42 changes were seen. Significant BP reduction was observed in uncontrolled HTN, and it was related to increase in T-tau (p = 0.001) and P-tau 181 (p < 0.001). DISCUSSION: Longitudinal increases in T-tau and P-tau 181 were observed in most subjects; however, only uncontrolled HTN had both markers increase alongside BP reductions. We speculate cumulative vascular injury renders the brain susceptible to relative hypoperfusion with BP reduction. HIGHLIGHTS: Over the course of the study, participants with uncontrolled HTN at baseline showed greater accumulation of CSF total tau and phospho-tau181 (P-tau 181) than subjects with normal BP or with controlled HTN. In the group with uncontrolled HTN, increases in total tau and P-tau 181 coincided with reduction in BP. We believe this highlights the role of HTN in vascular injury and suggests decline in cerebral perfusion resulting in increased biomarker concentrations in CSF. Medication use was the main factor differentiating controlled from uncontrolled HTN, indicating that earlier treatment was beneficial for preventing accumulations of pathology.

2.
Sci Rep ; 13(1): 15089, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37699966

RESUMO

Abnormal cognitive ageing, including dementia, poses serious challenges to health and social systems in ageing populations. As such, characterizing factors associated with abnormal cognitive ageing and developing needed preventive measures are of great importance. The ε4 allele of the Apolipoprotein E gene (APOE4) is a well-known genetic risk factor for late-onset Alzheimer's disease. APOE4 carriers are also at elevated risk of cardiovascular diseases which are associated with increased risk of cognitive impairment. On the other hand, APOE4 is known to be associated with reduced risk of multiple common types of cancer-a major age-related disease and leading cause of mortality. We conducted the first-ever study of APOE4's opposing effects on cognitive decline and mortality using competing risk models considering two types of death-death with high-amounts versus low-amounts of autopsy-assessed Alzheimer's neuropathology. We observed that APOE4 was associated with decreased mortality risk in people who died with low amounts of Alzheimer's-type neuropathology, but APOE4 was associated with increased mortality risk in people who died with high amounts of Alzheimer's-type neuropathology, a major risk factor of cognitive impairment. Possible preventive measures of abnormal cognitive ageing are also discussed.


Assuntos
Doença de Alzheimer , Apolipoproteína E4 , Humanos , Envelhecimento/genética , Doença de Alzheimer/genética , Apolipoproteína E4/genética , Cognição , Transtornos de Início Tardio , Fatores de Risco
3.
Fluids Barriers CNS ; 19(1): 21, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35287702

RESUMO

BACKGROUND: In sporadic Alzheimer's disease (AD), brain amyloid-beta (Aß) deposition is believed to be a consequence of impaired Aß clearance, but this relationship is not well established in living humans. CSF clearance, a major feature of brain glymphatic clearance (BGC), has been shown to be abnormal in AD murine models. MRI phase contrast and intrathecally delivered contrast studies have reported reduced CSF flow in AD. Using PET and tau tracer 18F-THK5117, we previously reported that the ventricular CSF clearance of the PET tracer was reduced in AD and associated with elevated brain Aß levels. METHODS: In the present study, we use two PET tracers, 18F-THK5351 and 11C-PiB to estimate CSF clearance calculated from early dynamic PET frames in 9 normal controls and 15 AD participants. RESULTS: we observed that the ventricular CSF clearance measures were correlated (r = 0.66, p < 0.01), with reductions in AD of 18 and 27%, respectively. We also replicated a significant relationship between ventricular CSF clearance (18F-THK5351) and brain Aß load (r = - 0.64, n = 24, p < 0.01). With a larger sample size, we extended our observations to show that reduced CSF clearance is associated with reductions in cortical thickness and cognitive performance. CONCLUSIONS: Overall, the findings support the hypothesis that failed CSF clearance is a feature of AD that is related to Aß deposition and to the pathology of AD. Longitudinal studies are needed to determine whether failed CSF clearance is a predictor of progressive amyloidosis or its consequence.


Assuntos
Doença de Alzheimer , Amiloidose , Doença de Alzheimer/complicações , Peptídeos beta-Amiloides , Amiloidose/complicações , Amiloidose/patologia , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Humanos , Imageamento por Ressonância Magnética , Camundongos
4.
Pediatr Diabetes ; 22(5): 816-822, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33909322

RESUMO

OBJECTIVE: This study evaluated costs and healthcare utilization associated with a culturally-sensitive, medical and education program for pediatric Latino patients with type 1 diabetes. RESEARCH DESIGN AND METHODS: Program participants included Latino children ages 1-20 years old diagnosed with type 1 diabetes (n = 57). Control subjects with type 1 diabetes were matched by age, sex, and zip code to intervention participants from the Colorado All Payer Claims Database. Data included emergency department (ED) visits, hospitalizations, demographic information, and health insurance claims data 180 days prior to program start/index date through 1 year after program start/index date. We tracked program staff time and estimated costs for healthcare utilization using data from the scientific literature. Generalized Estimating Equation (GEE) models with logit link were used to estimate group differences in probabilities of ED visits and hospitalizations over 6-month periods pre/post-study, accounting for correlation of within-subject data across time points. Sensitivity analyses modeled longer-term cost differences under different assumptions. RESULTS: The intervention group had fewer hospitalizations, 2% versus 12% of controls (p = 0.047,OR = 0.13;95%CI: 0.02-0.97) for 6 months following start date. The intervention group had fewer ED visits, 19% versus 32% in controls (n.s.; p = 0.079,OR = 0.52;95%CI:0.25-1.08) and significantly fewer hospitalizations, 4% versus 15% of controls (p = 0.039,OR = 0.21;95%CI: 0.05-0.93) 6-12 months post-start date. One-year per-patient program costs of $633 and healthcare cost savings of $2710 yielded total per-patient savings of $2077, or a 5-year cost savings of $14,106. CONCLUSION: This unique type 1 diabetes management program altered health service utilization of program participants, reducing major healthcare cost drivers, ED visits, and hospitalizations.


Assuntos
Competência Cultural , Diabetes Mellitus Tipo 1 , Custos de Cuidados de Saúde/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Consultas Médicas Compartilhadas , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Colorado/epidemiologia , Análise Custo-Benefício , Diabetes Mellitus Tipo 1/economia , Diabetes Mellitus Tipo 1/etnologia , Diabetes Mellitus Tipo 1/terapia , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Lactente , Masculino , Modelos Econômicos , Consultas Médicas Compartilhadas/economia , Consultas Médicas Compartilhadas/estatística & dados numéricos , Adulto Jovem
5.
Clin Diabetes ; 38(3): 291-294, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32699479

RESUMO

Quality Improvement Success Stories are published by the American Diabetes Association in collaboration with the American College of Physicians, Inc., and the National Diabetes Education Program. This series is intended to highlight best practices and strategies from programs and clinics that have successfully improved the quality of care for people with diabetes or related conditions. Each article in the series is reviewed and follows a standard format developed by the editors of Clinical Diabetes. The following article describes the establishment of a Diabetes Prevention Clinic for veterans with prediabetes.

6.
Headache ; 60(2): 441-456, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31981227

RESUMO

BACKGROUND: Relaxation, biofeedback, and cognitive behavioral therapy are evidence-based behavioral therapies for migraine. Despite such efficacy, research shows that only about half of patients initiate behavioral therapy recommended by their headache specialists. OBJECTIVE: Motivational interviewing (MI) is a widely used method to help patients explore and overcome ambivalence to enact positive life changes. We tested the hypothesis that telephone-based MI would improve initiation, scheduling, and attending behavioral therapy for migraine. METHODS: Single-blind randomized controlled trial comparing telephone-based MI to treatment as usual (TAU). Participants were recruited during their appointments with headache specialists at two sites of a New York City medical center. INCLUSION CRITERIA: ages from 16 to 80, migraine diagnosis by United Council of Neurologic Subspecialty fellowship trained and/or certified headache specialist, and referral for behavioral therapy for prevention in the appointment of recruitment. EXCLUSION CRITERIA: having done behavioral therapy for migraine in the past year. Participants in the MI group received up to 5 MI calls. TAU participants were called after 3 months for general follow-up data. The prespecified primary outcome was scheduling a behavioral therapy appointment, and secondary outcomes were initiating and attending a behavioral therapy appointment. RESULTS: 76 patients were enrolled and randomized (MI = 36, TAU = 40). At baseline, the mean number of headache days was 12.0 ± 9.0. Self-reported anxiety was present for 36/52 (69.2%) and depression for 30/52 (57.7%). Follow-up assessments were completed for 77.6% (59/76, MI = 32, TAU = 27). The mean number of MI calls per participant was 2.69 ± 1.56 [0 to 5]. There was a greater likelihood of those in the MI group to initiating an appointment (22/32, 68.8% vs 11/27, 40.7%, P = .0309). There were no differences in appointment scheduling or attendance. Reasons stated for not initiating behavioral therapy were lack of time, lack of insurance/funding, prioritizing other treatments, and travel plans. CONCLUSIONS: Brief telephone-based MI may improve rates of initiation of behavioral therapy for migraine, but other barriers appear to lessen the impact on scheduling and attending behavioral therapy appointments.


Assuntos
Terapia Comportamental , Transtornos de Enxaqueca/terapia , Entrevista Motivacional , Avaliação de Resultados em Cuidados de Saúde , Aceitação pelo Paciente de Cuidados de Saúde , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Projetos Piloto , Método Simples-Cego , Telemedicina , Telefone , Adulto Jovem
7.
Ann Surg Oncol ; 26(13): 4302-4309, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31529311

RESUMO

INTRODUCTION: Ductal carcinoma in situ (DCIS) with foci of invasion measuring ≤ 1 mm (DCISM), represents < 1% of all invasive breast cancers. Sentinel lymph node biopsy (SLNB) has been a standard component of surgery for patients with invasive carcinoma or extensive DCIS. We hypothesize that selective performance of SLNB may be appropriate given the low incidence of sentinel node (SN) metastasis for DCISM. We investigated the clinicopathologic predictors for SN positivity in DCISM, to identify which patients might benefit from SLNB. METHODS: A retrospective review of the National Cancer Database was performed for cases from 2012 to 2015. Clinical and tumor characteristics, including SN results, were evaluated, and Pearson's Chi square tests and logistic regression were performed. RESULTS: Of 7803 patients with DCISM, 306 (4%) had at least one positive SN. Patients with positive SNs were younger, more often of Black race, had higher-grade histology and larger tumor size, and were more likely to have lymphovascular invasion (LVI; all p < 0.001). In an adjusted model, the presence of LVI was associated with the highest odds ratio (OR) for node positivity (OR 8.80, 95% confidence interval 4.56-16.96). CONCLUSIONS: Among women with DCISM, only 4% had a positive SN. Node positivity was associated with more extensive and higher-grade DCIS, and the presence of LVI was strongly correlated with node positivity. Our data suggest that LVI is the most important factor in determining which patients with DCISM will benefit from SN biopsy.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/secundário , Nomogramas , Linfonodo Sentinela/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Invasividade Neoplásica , Valor Preditivo dos Testes , Estudos Retrospectivos , Adulto Jovem
8.
Alzheimers Dement (Amst) ; 11: 483-492, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31334328

RESUMO

INTRODUCTION: Plasma tau may be an accessible biomarker for Alzheimer's disease (AD), but the correlation between plasma and cerebrospinal fluid (CSF) tau and the value of combining plasma tau with CSF tau and phospho-tau (P-tau) are still unclear. METHODS: Plasma-tau, CSF-tau, and P-tau were measured in 97 subjects, including elderly cognitively normal controls (n = 68) and patients with AD (n = 29) recruited at the NYU Center for Brain Health, with comprehensive neuropsychological and magnetic resonance imaging evaluations. RESULTS: Plasma tau was higher in patients with AD than cognitively normal controls (P < .001, area under the receiver operating characteristic curve = 0.79) similarly to CSF tau and CSF P-tau and was negatively correlated with cognition in AD. Plasma and CSF tau measures were poorly correlated. Adding plasma tau to CSF tau or CSF P-tau significantly increased the areas under the receiver operating characteristic curve from 0.80 and 0.82 to 0.87 and 0.88, respectively. DISCUSSION: Plasma tau is higher in AD independently from CSF-tau. Importantly, adding plasma tau to CSF tau or P-tau improves diagnostic accuracy, suggesting that plasma tau may represent a useful biomarker for AD, especially when added to CSF tau measures.

9.
Ann Surg Oncol ; 26(10): 3337-3343, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31240590

RESUMO

BACKGROUND: Growing evidence suggests that the tumor immune microenvironment influences breast cancer development and prognosis. Density of tumor-infiltrating lymphocytes (TILs) within invasive breast cancer is correlated with response to therapy, especially in triple-negative disease. The clinical relevance and outcomes of TILs within ductal carcinoma in situ (DCIS) are less understood. METHODS: Our institutional database of 668 patients with pure DCIS from 2010 to 2018 was queried. TILs were evaluated by International TILs Working Group guidelines. Percentage of TILs was assessed from the densest focus (hotspot) in one high-power field of stroma touching the basement membrane. Statistical methods included cluster analyses (to define sparse versus dense TILs), logistic, and Cox regression models. RESULTS: Sixty-nine patients with DCIS and TILs were evaluated, of whom 54 (78%) were treated by breast-conserving surgery. Thirteen (19%) patients had ipsilateral recurrence. Each recurrence (n = 13) was matched to four controls (n = 56) based on date of surgery. Median follow-up was 6.7 years. TILs were defined as sparse (< 45%) or dense (≥ 45%). Dense TILs were associated with younger age (p = 0.045), larger tumor size (p < 0.001), high nuclear grade (p = 0.010), comedo histology (p = 0.033), necrosis (p = 0.027), estrogen receptor (ER) negativity (p = 0.037), and ipsilateral recurrence (p = 0.001). Nine patients with dense TILs had mean time to recurrence of 73.5 months compared with four patients with sparse TILs with mean time to recurrence of 97.9 months (p = 0.003). CONCLUSIONS: Dense TILs were significantly associated with age, tumor size, nuclear grade, comedo histology, necrosis, and ER status and was a significant predictor of recurrence in patients with pure DCIS.


Assuntos
Neoplasias da Mama/imunologia , Carcinoma Ductal de Mama/imunologia , Carcinoma Intraductal não Infiltrante/imunologia , Linfócitos do Interstício Tumoral/imunologia , Mastectomia Segmentar/métodos , Recidiva Local de Neoplasia/imunologia , Microambiente Tumoral/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/cirurgia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Prognóstico
11.
Sleep ; 42(6)2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-30794315

RESUMO

STUDY OBJECTIVES: To determine the effect of self-reported clinical diagnosis of obstructive sleep apnea (OSA) on longitudinal changes in brain amyloid PET and CSF biomarkers (Aß42, T-tau, and P-tau) in cognitively normal (NL), mild cognitive impairment (MCI), and Alzheimer's disease (AD) elderly. METHODS: Longitudinal study with mean follow-up time of 2.52 ± 0.51 years. Data were obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. Participants included 516 NL, 798 MCI, and 325 AD elderly. Main outcomes were annual rate of change in brain amyloid burden (i.e. longitudinal increases in florbetapir PET uptake or decreases in CSF Aß42 levels); and tau protein aggregation (i.e. longitudinal increases in CSF total tau [T-tau] and phosphorylated tau [P-tau]). Adjusted multilevel mixed effects linear regression models with randomly varying intercepts and slopes was used to test whether the rate of biomarker change differed between participants with and without OSA. RESULTS: In NL and MCI groups, OSA+ subjects experienced faster annual increase in florbetapir uptake (B = .06, 95% CI = .02, .11 and B = .08, 95% CI = .05, .12, respectively) and decrease in CSF Aß42 levels (B = -2.71, 95% CI = -3.11, -2.35 and B = -2.62, 95% CI = -3.23, -2.03, respectively); as well as increases in CSF T-tau (B = 3.68, 95% CI = 3.31, 4.07 and B = 2.21, 95% CI = 1.58, 2.86, respectively) and P-tau (B = 1.221, 95% CI = 1.02, 1.42 and B = 1.74, 95% CI = 1.22, 2.27, respectively); compared with OSA- participants. No significant variations in the biomarker changes over time were seen in the AD group. CONCLUSIONS: In both NL and MCI, elderly, clinical interventions aimed to treat OSA are needed to test if OSA treatment may affect the progression of cognitive impairment due to AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/análise , Disfunção Cognitiva/fisiopatologia , Apneia Obstrutiva do Sono/fisiopatologia , Proteínas tau/análise , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Encéfalo/fisiopatologia , Cognição/fisiologia , Progressão da Doença , Feminino , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino , Fosforilação
12.
Hypertension ; 73(1): 197-205, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30571554

RESUMO

Although there is an increasing agreement that hypertension is associated with cerebrovascular compromise, relationships between blood pressure (BP) and cerebral blood flow are not fully understood. It is not known what BP level, and consequently what therapeutic goal, is optimal for brain perfusion. Moreover, there is limited data on how BP affects hippocampal perfusion, a structure critically involved in memory. We conducted a cross-sectional (n=445) and longitudinal (n=185) study of adults and elderly without dementia or clinically apparent stroke, who underwent clinical examination and brain perfusion assessment (age 69.2±7.5 years, 62% women, 45% hypertensive). Linear models were used to test baseline BP-blood flow relationship and to examine how changes in BP influence changes in perfusion. In the entire group, systolic BP (SBP) was negatively related to cortical (ß=-0.13, P=0.005) and hippocampal blood flow (ß=-0.12, P=0.01). Notably, this negative relationship was apparent already in subjects without hypertension. Hypertensive subjects showed a quadratic relationship between SBP and hippocampal blood flow (ß=-1.55, P=0.03): Perfusion was the highest in subjects with mid-range SBP around 125 mm Hg. Longitudinally, in hypertensive subjects perfusion increased with increased SBP at low baseline SBP but increased with decreased SBP at high baseline SBP. Cortical and hippocampal perfusion decrease with increasing SBP across the entire BP spectrum. However, in hypertension, there seems to be a window of mid-range SBP which maximizes perfusion.


Assuntos
Pressão Sanguínea/fisiologia , Córtex Cerebral , Circulação Cerebrovascular/fisiologia , Hipocampo/irrigação sanguínea , Hipertensão , Idoso , Anti-Hipertensivos/uso terapêutico , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/diagnóstico por imagem , Correlação de Dados , Estudos Transversais , Feminino , Hipocampo/diagnóstico por imagem , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , New York , Fluxo Sanguíneo Regional
13.
Eur J Nucl Med Mol Imaging ; 45(9): 1596-1604, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29704038

RESUMO

PURPOSE: Off-target binding in the reference region is a challenge for recent tau tracers 18F-AV-1451 and 18F-THK5351. The conventional standardized uptake value ratio (SUVR) method relies on the average uptake from an unaffected tissue sample, and therefore is susceptible to biases from off-target binding as well as variability among individuals in the reference region. We propose a new method, standardized uptake value peak-alignment (SUVP), to reduce the bias of the SUVR, and improve the quantitative assessment of tau deposition. METHODS: The SUVP normalizes uptake values by their mode and standard deviation. Instead of using a reference region, the SUVP derives the contrast from unaffected voxels over the whole brain. Using SUVP and SUVR methods, we evaluated the global and regional tau binding of 18F-THK5351 and 18F-AV-1451 on two independent cohorts (N = 18 and 32, respectively), each with cognitively normal (NL) subjects and Alzheimer's disease (AD) subjects. RESULTS: Both tracers showed significantly increased binding for AD in the targeted cortical areas. In the temporal cortex, SUVP had a higher classification success rate (CSR) than SUVR (0.96 vs 0.89 for 18F-THK5351; 0.86 vs 0.75 for 18F-AV-1451), as well as higher specificity under fixed sensitivity around 0.80 (0.70 vs 0.45 specificity for 18F-THK5351; 1.00 vs 0.78 for 18F-AV-1451). In the cerebellar cortex, an AD-NL group difference with effect size (Cohen's d) of 0.62 was observed for AV-1451, confirming the limitation of the SUVR approach using this region as a reference. A smaller cerebellar effect size (0.09) was observed for THK5351. CONCLUSION: The SUVP method reduces the bias of the reference region and improves the NL-AD classification compared to the SUVR approach.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Aminopiridinas/farmacocinética , Carbolinas/farmacocinética , Tomografia por Emissão de Pósitrons , Quinolinas/farmacocinética , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Neurobiol Aging ; 65: 201-205, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29499501

RESUMO

Alzheimer's disease (AD) is known to be associated with loss of cholinergic neurons in the nucleus basalis of Meynert, located in the posterior basal forebrain. Structural changes of septal nuclei, located in the anterior basal forebrain, have not been well studied in AD. Using a validated algorithm, we manually traced septal nuclei on high-resolution coronal magnetic resonance imaging (MRI) in 40 subjects with mild cognitive impairment (MCI) or AD, 89 healthy controls, and 18 subjects who were cognitively normal at the time of MRI but went on to develop AD an average of 2.8 years later. We found that cognitively normal subjects destined to develop AD in the future had enlarged septal nuclei as compared to both healthy controls and patients with current MCI or AD. To our knowledge, this is the first time a brain structure has been found to be enlarged in association with risk of AD. Further research is needed to determine if septal enlargement reflects neuroplastic compensation, amyloid deposition, inflammation, or another process and to determine whether it can serve as an early MRI biomarker of AD.


Assuntos
Doença de Alzheimer/etiologia , Doença de Alzheimer/patologia , Prosencéfalo Basal/patologia , Voluntários Saudáveis , Núcleos Septais/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Prosencéfalo Basal/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Feminino , Humanos , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Risco , Núcleos Septais/diagnóstico por imagem , Fatores de Tempo
15.
PLoS One ; 13(2): e0191240, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29415068

RESUMO

Cerebrospinal fluid (CSF) studies consistently show that CSF levels of amyloid-beta 1-42 (Aß42) are reduced and tau levels increased prior to the onset of cognitive decline related to Alzheimer's disease (AD). However, the preclinical prediction accuracy for low CSF Aß42 levels, a surrogate for brain Aß42 deposits, is not high. Moreover, the pathology data suggests a course initiated by tauopathy contradicting the contemporary clinical view of an Aß initiated cascade. CSF Aß42 and tau data from 3 normal aging cohorts (45-90 years) were combined to test both cross-sectional (n = 766) and longitudinal (n = 651) hypotheses: 1) that the relationship between CSF levels of Aß42 and tau are not linear over the adult life-span; and 2) that non-linear models improve the prediction of cognitive decline. Supporting the hypotheses, the results showed that a u-shaped quadratic fit (Aß2) best describes the relationship for CSF Aß42 with CSF tau levels. Furthermore we found that the relationship between Aß42 and tau changes with age-between 45 and 70 years there is a positive linear association, whereas between 71 and 90 years there is a negative linear association between Aß42 and tau. The quadratic effect appears to be unique to Aß42, as Aß38 and Aß40 showed only positive linear relationships with age and CSF tau. Importantly, we observed the prediction of cognitive decline was improved by considering both high and low levels of Aß42. Overall, these data suggest an earlier preclinical stage than currently appreciated, marked by CSF elevations in tau and accompanied by either elevations or reductions in Aß42. Future studies are needed to examine potential mechanisms such as failing CSF clearance as a common factor elevating CSF Aßxx analyte levels prior to Aß42 deposition in brain.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Fragmentos de Peptídeos/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano , Adulto , Fatores Etários , Idoso , Doença de Alzheimer/patologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dinâmica não Linear , Punção Espinal
16.
Am J Respir Crit Care Med ; 197(7): 933-943, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29125327

RESUMO

RATIONALE: Recent evidence suggests that obstructive sleep apnea (OSA) may be a risk factor for developing mild cognitive impairment and Alzheimer's disease. However, how sleep apnea affects longitudinal risk for Alzheimer's disease is less well understood. OBJECTIVES: To test the hypothesis that there is an association between severity of OSA and longitudinal increase in amyloid burden in cognitively normal elderly. METHODS: Data were derived from a 2-year prospective longitudinal study that sampled community-dwelling healthy cognitively normal elderly. Subjects were healthy volunteers between the ages of 55 and 90, were nondepressed, and had a consensus clinical diagnosis of cognitively normal. Cerebrospinal fluid amyloid ß was measured using ELISA. Subjects received Pittsburgh compound B positron emission tomography scans following standardized procedures. Monitoring of OSA was completed using a home sleep recording device. MEASUREMENTS AND MAIN RESULTS: We found that severity of OSA indices (AHIall [F1,88 = 4.26; P < 0.05] and AHI4% [F1,87 = 4.36; P < 0.05]) were associated with annual rate of change of cerebrospinal fluid amyloid ß42 using linear regression after adjusting for age, sex, body mass index, and apolipoprotein E4 status. AHIall and AHI4% were not associated with increases in ADPiB-mask (Alzheimer's disease vulnerable regions of interest Pittsburg compound B positron emission tomography mask) most likely because of the small sample size, although there was a trend for AHIall (F1,28 = 2.96, P = 0.09; and F1,28 = 2.32, not significant, respectively). CONCLUSIONS: In a sample of cognitively normal elderly, OSA was associated with markers of increased amyloid burden over the 2-year follow-up. Sleep fragmentation and/or intermittent hypoxia from OSA are likely candidate mechanisms. If confirmed, clinical interventions for OSA may be useful in preventing amyloid build-up in cognitively normal elderly.


Assuntos
Peptídeos beta-Amiloides/líquido cefalorraquidiano , Apneia Obstrutiva do Sono/metabolismo , Idoso , Idoso de 80 Anos ou mais , Encéfalo/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Estudos Prospectivos , Índice de Gravidade de Doença
17.
J Nucl Med ; 58(9): 1471-1476, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28302766

RESUMO

Evidence supporting the hypothesis that reduced cerebrospinal fluid (CSF) clearance is involved in the pathophysiology of Alzheimer disease (AD) comes primarily from rodent models. However, unlike rodents, in which predominant extracranial CSF egress is via olfactory nerves traversing the cribriform plate, human CSF clearance pathways are not well characterized. Dynamic PET with 18F-THK5117, a tracer for tau pathology, was used to estimate the ventricular CSF time-activity as a biomarker for CSF clearance. We tested 3 hypotheses: extracranial CSF is detected at the superior turbinates; CSF clearance is reduced in AD; and CSF clearance is inversely associated with amyloid deposition. Methods: Fifteen subjects, 8 with AD and 7 normal control volunteers, were examined with 18F-THK5117. Ten subjects additionally underwent 11C-Pittsburgh compound B (11C-PiB) PET scanning, and 8 were 11C-PiB-positive. Ventricular time-activity curves of 18F-THK5117 were used to identify highly correlated time-activity curves from extracranial voxels. Results: For all subjects, the greatest density of CSF-positive extracranial voxels was in the nasal turbinates. Tracer concentration analyses validated the superior nasal turbinate CSF signal intensity. AD patients showed ventricular tracer clearance reduced by 23% and 66% fewer superior turbinate CSF egress sites. Ventricular CSF clearance was inversely associated with amyloid deposition. Conclusion: The human nasal turbinate is part of the CSF clearance system. Lateral ventricle and superior nasal turbinate CSF clearance abnormalities are found in AD. Ventricular CSF clearance reductions are associated with increased brain amyloid depositions. These data suggest that PET-measured CSF clearance is a biomarker of potential interest in AD and other neurodegenerative diseases.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Compostos de Anilina/líquido cefalorraquidiano , Compostos de Anilina/farmacocinética , Benzotiazóis/líquido cefalorraquidiano , Benzotiazóis/farmacocinética , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Quinolinas/líquido cefalorraquidiano , Quinolinas/farmacocinética , Tiazóis
18.
Neurology ; 87(18): 1907-1915, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27708129

RESUMO

OBJECTIVE: To assess whether multifocal, high-frequency repetitive transcranial magnetic stimulation (rTMS) of motor and prefrontal cortex benefits motor and mood symptoms in patients with Parkinson disease (PD). METHODS: Patients with PD and depression were enrolled in this multicenter, double-blind, sham-controlled, parallel-group study of real or realistic (electric) sham rTMS. Patients were randomized to 1 of 4 groups: bilateral M1 ( + sham dorsolateral prefrontal cortex [DLPFC]), DLPFC ( + sham M1), M1 + DLPFC, or double sham. The TMS course consisted of 10 daily sessions of 2,000 stimuli for the left DLPFC and 1,000 stimuli for each M1 (50 × 4-second trains of 40 stimuli at 10 Hz). Patients were evaluated at baseline, at 1 week, and at 1, 3, and 6 months after treatment. Primary endpoints were changes in motor function assessed with the Unified Parkinson's Disease Rating Scale-III and in mood with the Hamilton Depression Rating Scale at 1 month. RESULTS: Of the 160 patients planned for recruitment, 85 were screened, 61 were randomized, and 50 completed all study visits. Real M1 rTMS resulted in greater improvement in motor function than sham at the primary endpoint (p < 0.05). There was no improvement in mood in the DLPFC group compared to the double-sham group, as well as no benefit to combining M1 and DLPFC stimulation for either motor or mood symptoms. CONCLUSIONS: In patients with PD with depression, M1 rTMS is an effective treatment of motor symptoms, while mood benefit after 2 weeks of DLPFC rTMS is not better than sham. Targeting both M1 and DLPFC in each rTMS session showed no evidence of synergistic effects. CLINICALTRIALSGOV IDENTIFIER: NCT01080794. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that in patients with PD with depression, M1 rTMS leads to improvement in motor function while DLPFC rTMS does not lead to improvement in depression compared to sham rTMS.


Assuntos
Transtornos do Humor/etiologia , Transtornos do Humor/terapia , Doença de Parkinson/complicações , Córtex Pré-Frontal/fisiologia , Idoso , Análise de Variância , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/terapia , Escalas de Graduação Psiquiátrica , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento
19.
Sleep ; 39(11): 2041-2048, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27568802

RESUMO

STUDY OBJECTIVES: Emerging evidence suggests a role for sleep in contributing to the progression of Alzheimer disease (AD). Slow wave sleep (SWS) is the stage during which synaptic activity is minimal and clearance of neuronal metabolites is high, making it an ideal state to regulate levels of amyloid beta (Aß). We thus aimed to examine relationships between concentrations of Aß42 in the cerebrospinal fluid (CSF) and measures of SWS in cognitively normal elderly subjects. METHODS: Thirty-six subjects underwent a clinical and cognitive assessment, a structural MRI, a morning to early afternoon lumbar puncture, and nocturnal polysomnography. Correlations and linear regression analyses were used to assess for associations between CSF Aß42 levels and measures of SWS controlling for potential confounders. Resulting models were compared to each other using ordinary least squared linear regression analysis. Additionally, the participant sample was dichotomized into "high" and "low" Aß42 groups to compare SWS bout length using survival analyses. RESULTS: A significant inverse correlation was found between CSF Aß42 levels, SWS duration and other SWS characteristics. Collectively, total SWA in the frontal lead was the best predictor of reduced CSF Aß42 levels when controlling for age and ApoE status. Total sleep time, time spent in NREM1, NREM2, or REM sleep were not correlated with CSF Aß42. CONCLUSIONS: In cognitively normal elderly, reduced and fragmented SWS is associated with increases in CSF Aß42, suggesting that disturbed sleep might drive an increase in soluble brain Aß levels prior to amyloid deposition.


Assuntos
Peptídeos beta-Amiloides/líquido cefalorraquidiano , Fragmentos de Peptídeos/líquido cefalorraquidiano , Fases do Sono/fisiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/fisiopatologia , Biomarcadores/líquido cefalorraquidiano , Cognição/fisiologia , Feminino , Humanos , Modelos Lineares , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Polissonografia
20.
Alzheimers Dement (Amst) ; 2: 95-104, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27239540

RESUMO

INTRODUCTION: Hypertension, hypercholesterolemia, and obesity increase the risk of dementia. Although their detection is commonly followed by an introduction of treatment, little is known about how medications frequently used to treat vascular risk affect amyloid deposition. METHODS: A cross-sectional study of 156 subjects who underwent positron emission tomography with PiB. Using linear regression, we tested whether blood pressure, cholesterol, overweight/obese status, angiotensin receptor blockers (ARBs), beta-blockers, diuretics, angiotensin converting enzyme inhibitors, and statins predicted amyloid deposition. RESULTS: The use of ARBs (ß = -.15, P = .044) and diuretics (ß = -.20, P = .006) predicted less amyloid accumulation; older age (ß = .29, P < .001) and statins (ß = .23, P = .004) were related to greater amyloid deposition. Overweight and/or obese women had more cortical amyloid than their peers. DISCUSSION: Prospective studies should confirm effects of drugs and increased body weight on amyloid accumulation and establish whether they translate into measurable clinical outcomes. Women may be more susceptible to harmful effects of obesity.

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