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1.
Gynecol Oncol ; 186: 26-34, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38555766

RESUMEN

OBJECTIVES: Alterations in the tumor suppressor TP53 gene are the most common mutations in high grade serous ovarian carcinoma. The impact of TP53 mutations on clinical outcomes and platinum resistance is controversial. We sought to evaluate the genomic profile of high grade serous ovarian carcinoma and explore the association of TP53 mutations with platinum resistance. METHODS: Next generation sequencing data was obtained from our institutional database for patients with high grade serous ovarian carcinoma undergoing primary treatment. Sequencing data, demographic, and clinical information was reviewed. The primary outcome analyzed was time to recurrence or refractory diagnosis. Associations between the primary outcome and different classification schemes for TP53 mutations (structural, functional, hot spot, pathogenicity scores, immunohistochemical staining patterns) were performed. RESULTS: 209 patients met inclusion criteria. TP53 mutations were the most common mutation. There were no differences in platinum response with TP53 hotspot mutations or high pathogenicity scores. Presence of TP53 gain-of-function mutations or measure of TP53 gain-of function activity were not associated with platinum resistance. Immunohistochemical staining patterns correlated with expected TP53 protein function and were not associated with platinum resistance. CONCLUSIONS: TP53 hotspot mutations or high pathogenicity scores were not associated with platinum resistance or refractory disease. Contrary to prior studies, TP53 gain-of-function mutations were not associated with platinum resistance. Estimation of TP53 gain-of-function effect using missense mutation phenotype scores was not associated with platinum resistance. The polymorphic nature of TP53 mutations may be too complex to demonstrate effect using simple models, or response to platinum therapy may be independent of initiating TP53 mutation.


Asunto(s)
Cistadenocarcinoma Seroso , Resistencia a Antineoplásicos , Mutación , Neoplasias Ováricas , Proteína p53 Supresora de Tumor , Humanos , Femenino , Neoplasias Ováricas/genética , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología , Resistencia a Antineoplásicos/genética , Proteína p53 Supresora de Tumor/genética , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/patología , Cistadenocarcinoma Seroso/tratamiento farmacológico , Persona de Mediana Edad , Anciano , Adulto , Clasificación del Tumor , Anciano de 80 o más Años , Mutación con Ganancia de Función , Estudios Retrospectivos
2.
Alzheimers Dement ; 20(5): 3305-3321, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38539269

RESUMEN

INTRODUCTION: Published norms are typically cross-sectional and often are not sensitive to preclinical cognitive changes due to dementia. We developed and validated demographically adjusted cross-sectional and longitudinal normative standards using harmonized outcomes from two Alzheimer's disease (AD) risk-enriched cohorts. METHODS: Data from the Wisconsin Registry for Alzheimer's Prevention and the Wisconsin Alzheimer's Disease Research Center were combined. Quantile regression was used to develop unconditional (cross-sectional) and conditional (longitudinal) normative standards for 18 outcomes using data from cognitively unimpaired participants (N = 1390; mean follow-up = 9.25 years). Validity analyses (N = 2456) examined relationships between percentile scores (centiles), consensus-based cognitive statuses, and AD biomarker levels. RESULTS: Unconditional and conditional centiles were lower in those with consensus-based impairment or biomarker positivity. Similarly, quantitative biomarker levels were higher in those whose centiles suggested decline. DISCUSSION: This study presents normative standards for cognitive measures sensitive to pre-clinical changes. Future directions will investigate potential clinical applications of longitudinal normative standards. HIGHLIGHTS: Quantile regression was used to construct longitudinal norms for cognitive tests. Poorer percentile scores were related to concurrent diagnosis and Alzheimer's disease biomarkers. A ShinyApp was built to display test scores and norms and flag low performance.


Asunto(s)
Enfermedad de Alzheimer , Biomarcadores , Pruebas Neuropsicológicas , Humanos , Enfermedad de Alzheimer/diagnóstico , Masculino , Anciano , Femenino , Pruebas Neuropsicológicas/normas , Pruebas Neuropsicológicas/estadística & datos numéricos , Estudios Longitudinales , Wisconsin , Estudios Transversales , Disfunción Cognitiva/diagnóstico , Estudios de Cohortes , Cognición/fisiología , Anciano de 80 o más Años , Persona de Mediana Edad
3.
Cytotherapy ; 25(11): 1139-1144, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37589639

RESUMEN

BACKGROUND AIMS: Xerostomia, or the feeling of dry mouth, is a significant side effect of radiation therapy for patients with head and neck cancer (HNC). Preliminary data suggest that mesenchymal stromal/stem cells (MSCs) can improve salivary function. We performed a first-in-human pilot study of interferon gamma (IFNγ)-stimulated autologous bone marrow-derived MSCs, or MSC(M), for the treatment of radiation-induced xerostomia (RIX). Here we present the primary safety and secondary efficacy endpoints. METHODS: A single-center pilot clinical trial was conducted investigating the safety and tolerability of autologous IFNγ-stimulated MSC(M). The study was conducted under an approved Food and Drug Administration Investigational New Drug application using an institutional review board-approved protocol (NCT04489732). Patients underwent iliac crest bone marrow aspirate and MSC(M) were isolated, cultured, stimulated with IFNγ and cryopreserved for later use. Banked cells were thawed and allowed to recover in culture before patients received a single injection of 10 × 106 MSC(M) into the right submandibular gland under ultrasound guidance. The primary objective was determination of safety and tolerability by evaluating dose-limiting toxicity (DLT). A DLT was defined as submandibular pain >5 on a standard 10-point pain scale or any serious adverse event (SAE) within 1 month after injection. Secondary objectives included analysis of efficacy as measured by salivary quantification and using three validated quality of life instruments. Quantitative results are reported as mean and standard deviation. RESULTS: Six patients with radiation-induced xerostomia who had completed radiation at least 2 years previously (average 7.8 years previously) were enrolled in the pilot study. The median age was 71 (61-74) years. Five (83%) patients were male. Five patients (83%) were treated with chemoradiation and one patient (17%) with radiation alone. Grade 1 pain was seen in 50% of patients after submandibular gland injection; all pain resolved within 4 days. No patients reported pain 1 month after injection, with no SAE or other DLTs reported 1 month after injection. The analysis of secondary endpoints demonstrated a trend of increased salivary production. Three patients (50%) had an increase in unstimulated saliva at 1 and 3 months after MSC(M) injection. Quality of life surveys also showed a trend toward improvement. CONCLUSIONS: Injection of autologous IFNγ-stimulated MSC(M) into a singular submandibular gland of patients with RIX is safe and well tolerated in this pilot study. A trend toward an improvement in secondary endpoints of salivary quantity and quality of life was observed. This first-in-human study provides support for further investigation into IFNγ-stimulated MSC(M) injected in both submandibular glands as an innovative approach to treat RIX and improve quality of life for patients with HNC.


Asunto(s)
Neoplasias de Cabeza y Cuello , Células Madre Mesenquimatosas , Traumatismos por Radiación , Xerostomía , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Médula Ósea , Interferón gamma , Dolor , Proyectos Piloto , Calidad de Vida , Traumatismos por Radiación/etiología , Traumatismos por Radiación/terapia , Humedales , Xerostomía/etiología , Xerostomía/terapia
4.
Stat Med ; 42(15): 2590-2599, 2023 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-37002550

RESUMEN

Window mean survival time (WMST), a simple extension of restricted mean survival time (RMST), allows for clinicians to evaluate the mean survival difference between treatment groups in specific windows of time during the follow-up period of a trial. The advantages of WMST are numerous. Not only does it produce estimates of treatment effect that can be meaningfully interpreted, but also has power advantages over competing methods when hazards are non-proportional (NPH). WMST, like RMST, is currently underutilized due to clinicians' lack of familiarity with tests comparing mean survival times and the lack of tools to facilitate trial design with this endpoint. The aim of this article is to provide investigators with insights and software to design trials with WMST as the primary endpoint. Functions for performing power and sample size calculations are provided in the survWMST package in R available on GitHub.


Asunto(s)
Proyectos de Investigación , Humanos , Modelos de Riesgos Proporcionales , Tasa de Supervivencia , Tamaño de la Muestra , Factores de Tiempo , Análisis de Supervivencia
5.
Alzheimer Dis Assoc Disord ; 37(4): 310-314, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37698523

RESUMEN

AIM: To determine whether exposure to neurotoxins in midlife is associated with changes in blood-based biomarkers of neurodegeneration and Alzheimer disease pathology. METHODS: Blood cadmium, lead, neurofilament light (NfL) chain, total tau (TTau), and amyloid beta (Aß) 40 and Aß42 concentrations were measured in 1516 participants in the Beaver Dam Offspring Study. Linear mixed-effect models were used to determine associations between baseline cadmium and lead levels and baseline NfL, TTau, and Aß42/Aß40, and 10-year change in concentrations using repeated measures of these biomarkers as the outcome. RESULTS: In women, higher cadmium and lead levels were associated with higher baseline TTau concentrations. A higher baseline cadmium level was associated with lower baseline Aß42/Aß40 in both men and women. In age-sex-adjusted models, a doubling in baseline cadmium level was associated with a 0.2% (95% CI: 0.0, 0.3) higher increase per year in NfL concentrations. In men, a doubling of baseline lead level was associated with a 0.9% (95% CI: 0.1, 1.7) higher increase per year in TTau concentration. CONCLUSIONS: Participants with relatively higher levels of cadmium and lead had blood biomarker concentrations consistent with more neuronal damage and Alzheimer disease pathology. Environmental exposure to neurotoxins may contribute to neurodegeneration.


Asunto(s)
Enfermedad de Alzheimer , Masculino , Humanos , Femenino , Enfermedad de Alzheimer/patología , Plomo , Péptidos beta-Amiloides , Neurotoxinas , Cadmio , Proteínas tau , Biomarcadores
6.
Cytotherapy ; 24(5): 534-543, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35183442

RESUMEN

BACKGROUND: Xerostomia, or dry mouth, is a common side effect of head and neck radiation. Current treatment options for radiation-induced xerostomia are generally supportive in nature. Adult stem cells are the ultimate source for replenishment of salivary gland tissue. Bone marrow-derived mesenchymal stromal cells (BM-MSCs) are a viable cell-based therapy for xerostomia. We have undertaken studies enabling U.S. Food and Drug Administration Investigational New Drug status, demonstrating the normal phenotype, intact functionality, and pro-growth secretome of interferon-γ (IFNγ)-stimulated BM-MSCs taken from patients with head and neck cancer who have undergone radiation ± chemotherapy. Here we present the protocol of MARSH, a first-in-human clinical trial of bone marrow-derived, IFNγ-activated BM-MSCs for the treatment of radiation-induced xerostomia. METHODS: This single-center phase 1 dose-escalation with expansion cohort, non-placebo-controlled study will assess the safety and tolerability of BM-MSCs for the treatment of radiation-induced xerostomia in patients who had head and neck cancer. The phase 1 dose-escalation study will be a 3 + 3 design with staggered enrollment. A total of 21 to 30 subjects (9 to 18 in phase 1 study, 12 in expansion cohort) will be enrolled. The primary endpoint is determining the recommended phase 2 dose (RP2D) of IFNγ-stimulated BM-MSCs to enable further studies on the efficacy of BM-MSCs. Patients' bone marrow will be aspirated, and BM-MSCs will be expanded, stimulated with IFNγ, and injected into the submandibular gland. The RP2D will be determined by dose-limiting toxicities occurring within 1 month of BM-MSC injection. Secondary outcomes of saliva amounts and composition, ultrasound of salivary glands, and quality of life surveys will be taken at 3-, 6-, 12-, and 24-month visits. DISCUSSION: Autotransplantation of IFNγ-stimulated BM-MSCs in salivary glands after radiation therapy or chemoradiation therapy may provide an innovative remedy to treat xerostomia and restore quality of life. This is the first therapy for radiation-induced xerostomia that may be curative. TRIAL REGISTRATION: World Health Organization International Clinical Trials Registry Platform: NCT04489732.


Asunto(s)
Neoplasias de Cabeza y Cuello , Células Madre Mesenquimatosas , Traumatismos por Radiación , Xerostomía , Médula Ósea , Ensayos Clínicos Fase I como Asunto , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Calidad de Vida , Traumatismos por Radiación/terapia , Trasplante Autólogo , Humedales , Xerostomía/etiología , Xerostomía/terapia
7.
Stat Med ; 41(19): 3720-3736, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-35611993

RESUMEN

Window mean survival time (WMST) evaluates the mean survival between a lower time horizon, τ 0 $$ {\tau}_0 $$ , and an upper time horizon, τ 1 $$ {\tau}_1 $$ . As a flexible extension of restricted mean survival time, specific clinically relevant windows of time can be assessed for survival difference accompanied by a communicable interpretation of estimates and tests. In its original application, WMST required the pre-specification of a window through the selection of appropriate window bounds, τ 0 $$ {\tau}_0 $$ and τ 1 $$ {\tau}_1 $$ . In the instance of severe window misspecification of τ 0 $$ {\tau}_0 $$ and τ 1 $$ {\tau}_1 $$ , the analysis may suffer from low power and a less meaningful interpretation. In this article, we introduce versatile tests whose procedures are based on the simultaneous use of multiple WMST test statistics that are asymptotically normal under the null hypothesis of no difference between two groups. Simulations are performed to examine the power of the tests in moderate sample sizes when the data are uncensored to heavily censored with a ramp-up enrollment period. The survival scenarios chosen for simulation are intended to imitate those which are commonly encountered in oncology, especially in trials involving immunotherapies. Implementation of the procedures is discussed in two real data examples for illustration. Functions for performing versatile WMST tests are provided in the survWMST package in R.


Asunto(s)
Análisis de Supervivencia , Simulación por Computador , Humanos , Modelos de Riesgos Proporcionales , Tamaño de la Muestra , Tasa de Supervivencia
8.
J Neurophysiol ; 125(1): 184-198, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33206577

RESUMEN

Small alterations in extracellular H+ can profoundly alter neurotransmitter release by neurons. We examined mechanisms by which extracellular ATP induces an extracellular H+ flux from Müller glial cells, which surround synaptic connections throughout the vertebrate retina. Müller glia were isolated from tiger salamander retinae and H+ fluxes examined using self-referencing H+-selective microelectrodes. Experiments were performed in 1 mM HEPES with no bicarbonate present. Replacement of extracellular sodium by choline decreased H+ efflux induced by 10 µM ATP by 75%. ATP-induced H+ efflux was also reduced by Na+/H+ exchange inhibitors. Amiloride reduced H+ efflux initiated by 10 µM ATP by 60%, while 10 µM cariporide decreased H+ flux by 37%, and 25 µM zoniporide reduced H+ flux by 32%. ATP-induced H+ fluxes were not significantly altered by the K+/H+ pump blockers SCH28080 or TAK438, and replacement of all extracellular chloride with gluconate was without effect on H+ fluxes. Recordings of ATP-induced H+ efflux from cells that were simultaneously whole cell voltage clamped revealed no effect of membrane potential from -70 mV to 0 mV. Restoration of extracellular potassium after cells were bathed in 0 mM potassium produced a transient alteration in ATP-dependent H+ efflux. The transient response to extracellular potassium occurred only when extracellular sodium was present and was abolished by 1 mM ouabain, suggesting that alterations in sodium gradients were mediated by Na+/K+-ATPase activity. Our data indicate that the majority of H+ efflux elicited by extracellular ATP from isolated Müller cells is mediated by Na+/H+ exchange.NEW & NOTEWORTHY Glial cells are known to regulate neuronal activity, but the exact mechanism(s) whereby these "support" cells modulate synaptic transmission remains unclear. Small changes in extracellular levels of acidity are known to be particularly powerful regulators of neurotransmitter release. Here, we show that extracellular ATP, known to be a potent activator of glial cells, induces H+ efflux from retinal Müller (glial) cells and that the bulk of the H+ efflux is mediated by Na+/H+ exchange.


Asunto(s)
Adenosina Trifosfato/metabolismo , Células Ependimogliales/metabolismo , Protones , Intercambiadores de Sodio-Hidrógeno/metabolismo , Potenciales de Acción , Animales , Células Cultivadas , Células Ependimogliales/fisiología , Imidazoles/farmacología , Transporte Iónico , Pirroles/farmacología , Intercambiadores de Sodio-Hidrógeno/antagonistas & inhibidores , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Sulfonamidas/farmacología , Urodelos
9.
Radiology ; 299(3): 583-594, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33787334

RESUMEN

Background Although CT, endoscopic US, and PET are critical in determining the appropriate management of esophageal carcinoma (squamous cell carcinoma and adenocarcinoma), previous reports show that staging accuracy remains low, particularly for nodal involvement sensitivity. Purpose To perform a systematic review and meta-analysis to determine the diagnostic performance of MRI for multiple staging thresholds in patients with biopsy-proven esophageal carcinoma (differentiation of stage T0 disease from stage T1 or higher disease, differentiation of stage T2 or lower disease from stage T3 or higher disease, and differentiation of stage N0 disease from stage N1 or higher disease [where T refers to tumor stage and N refers to nodal stage]). Materials and Methods Studies of the diagnostic performance of MRI in determining the stage of esophageal carcinoma in patients before esophagectomy and pathologic staging between 2000 and 2019 were searched in PubMed, Scopus, Web of Science, and Cochrane Library by a librarian and radiation oncologist. Pooled diagnostic performance of MRI was calculated with a bivariate random effects model. Bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies (version 2) tool. Results Twenty studies with a total of 984 patients were included in the analysis. Pooled accuracy for stage T0 versus stage T1 or higher had a sensitivity of 92% (95% CI: 82, 96) and a specificity of 67% (95% CI: 51, 81). Pooled accuracy for stage T2 or lower versus stage T3 or higher had a sensitivity of 86% (95% CI: 76, 92) and a specificity of 86% (95% CI: 75, 93). Pooled accuracy for stage N0 versus stage N1 or higher had a sensitivity of 71% (95% CI: 60, 80) and a specificity of 72% (95% CI: 64, 79). The concern for applicability was low for the patient selection, index test, and reference test domains, except for 10% of studies (two of 20) that had unclear concern for patient selection applicability. Conclusion MRI has high sensitivity but low specificity for the detection of esophageal carcinoma, which shows promise for determining neoadjuvant therapy response and for detecting locally advanced disease for potential trimodality therapy. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Leeflang in this issue.


Asunto(s)
Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/patología , Imagen por Resonancia Magnética/métodos , Biopsia , Humanos , Estadificación de Neoplasias
10.
Stat Med ; 40(25): 5521-5533, 2021 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-34258772

RESUMEN

We propose a class of alternative estimates and tests to restricted mean survival time (RMST) which improves power in numerous survival scenarios while maintaining a level of interpretability. The industry standards for interpretable hypothesis tests in survival analysis, RMST and logrank tests (LRTs), can suffer from low power in cases where the proportional hazards assumption fails. In particular, when late differences occur between survival curves, our proposed estimate and class of tests, window mean survival time (WMST), outperforms both RMST and LRT without sacrificing interpretability, unlike weighted rank tests (WRTs). WMST has the added advantage of maintaining high power when the proportional hazards assumption is met, while WRTs do not. With testing methods often being chosen in advance of data collection, WMST can ensure adequate power without distributional assumptions and is robust to the choice of its restriction parameters. Functions for performing WMST analysis are provided in the survWM2 package in R.


Asunto(s)
Proyectos de Investigación , Humanos , Modelos de Riesgos Proporcionales , Análisis de Supervivencia , Tasa de Supervivencia
11.
J Int Neuropsychol Soc ; 27(5): 412-425, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33012297

RESUMEN

OBJECTIVE: This study investigated the latent factor structure of the NIH Toolbox Cognition Battery (NIHTB-CB) and its measurement invariance across clinical diagnosis and key demographic variables including sex, race/ethnicity, age, and education for a typical Alzheimer's disease (AD) research sample. METHOD: The NIHTB-CB iPad English version, consisting of 7 tests, was administered to 411 participants aged 45-94 with clinical diagnosis of cognitively unimpaired, dementia, mild cognitive impairment (MCI), or impaired not MCI. The factor structure of the whole sample was first examined with exploratory factor analysis (EFA) and further refined using confirmatory factor analysis (CFA). Two groups were classified for each variable (diagnosis or demographic factors). The confirmed factor model was next tested for each group with CFA. If the factor structure was the same between the groups, measurement invariance was then tested using a hierarchical series of nested two-group CFA models. RESULTS: A two-factor model capturing fluid cognition (executive function, processing speed, and memory) versus crystalized cognition (language) fit well for the whole sample and each group except for those with age < 65. This model generally had measurement invariance across sex, race/ethnicity, and education, and partial invariance across diagnosis. For individuals with age < 65, the language factor remained intact while the fluid cognition was separated into two factors: (1) executive function/processing speed and (2) memory. CONCLUSIONS: The findings mostly supported the utility of the battery in AD research, yet revealed challenges in measuring memory for AD participants and longitudinal change in fluid cognition.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/diagnóstico , Cognición , Función Ejecutiva , Análisis Factorial , Humanos , Pruebas Neuropsicológicas
12.
J Appl Philos ; 38(3): 479-496, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33821073

RESUMEN

We explore the ethics of deliberately exposing consenting adults to SARS-CoV-2 to induce immunity to the virus ('DEI' for short). We explain what a responsible DEI program might look like. We explore a consequentialist argument for DEI according to which DEI is a viable harm-reduction strategy. Then we consider a nonconsequentialist argument for DEI that draws on the moral significance of consent. Additionally, we consider arguments for the view that DEI is unethical on the grounds that, given that large-scale DEI would be highly likely to result in some severe illnesses and deaths, DEI amounts to a form of killing. Our thesis is that incorporating a DEI program alongside the status quo 'calibrate the curve' responses could have significant advantages at the early stages of pandemics. These potential advantages mean that, at a minimum, research into DEI would have been justified early in the COVID-19 pandemic and that DEI programs should be explored as potential additions to our overall approach to emerging pandemics in the future.

13.
Alzheimer Dis Assoc Disord ; 34(1): 31-39, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31385821

RESUMEN

BACKGROUND: Relationships between brain-derived neurotrophic factor (BDNF), insulin-like growth factor (IGF-1), aldosterone, and cognition in aging were evaluated in the population-based Epidemiology of Hearing Loss Study (1993 to present). METHODS: Beginning in 1998 to 2000, cognitive impairment was assessed by report of physician diagnoses and the Mini-Mental State Examination. In 2009 to 2010 and 2013 to 2016, information was collected on diagnosis of mild cognitive impairment/dementia. Decline in cognitive function was assessed by principal component analysis from additional tests administered during 2009 to 2010 and 2013 to 2016. BDNF, IGF-1, and aldosterone were measured in serum collected in 1998 to 2000. RESULTS: There were 1970 participants (mean age=66.9 y; 59.1% female) without cognitive impairment at baseline. Among women, low BDNF was associated with 16-year incident cognitive impairment [hazard ratio=1.76; 95% confidence interval (CI)=1.04, 2.98]. Among men, increasing IGF-1 was associated with decreased risk [per SD: relative risk (RR)=0.57; 95% CI=0.35, 0.92], whereas increasing aldosterone levels were associated with increased risk (per SD: RR=1.28; 95% CI=1.01, 1.62) for 5-year incident mild cognitive impairment/dementia. Overall, low BDNF was associated with increased risk (RR=1.52; 95% CI=1.02, 2.26) for 5-year cognitive decline. CONCLUSION: Low levels of serum BDNF and IGF-1 were associated with poorer cognition during aging. There may be differential biomarker effects by sex.


Asunto(s)
Envejecimiento/fisiología , Biomarcadores/sangre , Cognición/fisiología , Disfunción Cognitiva/diagnóstico , Factores Protectores , Anciano , Aldosterona/análisis , Aldosterona/sangre , Factor Neurotrófico Derivado del Encéfalo/análisis , Factor Neurotrófico Derivado del Encéfalo/sangre , Femenino , Humanos , Factor I del Crecimiento Similar a la Insulina/análisis , Estudios Longitudinales , Masculino , Pruebas Neuropsicológicas/estadística & datos numéricos , Estudios Prospectivos , Estados Unidos
14.
Clin Trials ; 17(5): 507-521, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32594788

RESUMEN

BACKGROUND: In randomized clinical trials with censored time-to-event outcomes, the logrank test is known to have substantial statistical power under the proportional hazards assumption and is widely adopted as a tool to compare two survival distributions. However, the proportional hazards assumption is impossible to validate in practice until the data are unblinded. However, the statistical analysis plan of a randomized clinical trial and in particular its primary analysis method must be pre-specified before any unblinded information may be reviewed. PURPOSE: The purpose of this article is to guide applied biostatisticians in the prespecification of a desired primary analysis method when a treatment effect with nonproportional hazards is anticipated. While articles proposing alternate statistical tests are aplenty, to the best of our knowledge, there is no article available that attempts to simplify the choice and prespecification of a primary statistical test under specific expected patterns on nonproportional hazards. We provide such guidance by reviewing various tests proposed as more powerful alternatives to the standard logrank test under nonproportional hazards and simultaneously comparing their performance under a wide variety of nonproportional hazards scenarios to elucidate their advantages and disadvantages. METHOD: In order to select the most preferable test for detecting specific differences between survival distributions of interest while controlling false positive rates, we review and assess the performance of weighted and adaptively weighted logrank tests, weighted and adaptively weighted Kaplan-Meier tests and versatile tests under various patterns of nonproportional hazards treatment effects through simulation. CONCLUSION: We validate some of the claimed properties of the proposed extensions and identify tests that may be more preferable under specific expected pattern of nonproportional hazards when such knowledge is available. We show that versatile tests, while achieving robustness to departures from proportional hazards, may lose interpretation of directionality (superiority or inferiority) and can only be seen to test departures from equality. Detailed summary and discussion of the performance of each test in terms of type I error rate and power are provided to formulate specific guidance about their applicability and use.


Asunto(s)
Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Análisis de Supervivencia , Simulación por Computador , Humanos , Estimación de Kaplan-Meier , Modelos de Riesgos Proporcionales , Tamaño de la Muestra
15.
J Int Neuropsychol Soc ; 25(1): 1-14, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30482257

RESUMEN

OBJECTIVES: A major challenge in cognitive aging is differentiating preclinical disease-related cognitive decline from changes associated with normal aging. Neuropsychological test authors typically publish single time-point norms, referred to here as unconditional reference values. However, detecting significant change requires longitudinal, or conditional reference values, created by modeling cognition as a function of prior performance. Our objectives were to create, depict, and examine preliminary validity of unconditional and conditional reference values for ages 40-75 years on neuropsychological tests. METHOD: We used quantile regression to create growth-curve-like models of performance on tests of memory and executive function using participants from the Wisconsin Registry for Alzheimer's Prevention. Unconditional and conditional models accounted for age, sex, education, and verbal ability/literacy; conditional models also included past performance on and number of prior exposures to the test. Models were then used to estimate individuals' unconditional and conditional percentile ranks for each test. We examined how low performance on each test (operationalized as <7th percentile) related to consensus-conference-determined cognitive statuses and subjective impairment. RESULTS: Participants with low performance were more likely to receive an abnormal cognitive diagnosis at the current visit (but not later visits). Low performance was also linked to subjective and informant reports of worsening memory function. CONCLUSIONS: The percentile-based methods and single-test results described here show potential for detecting troublesome within-person cognitive change. Development of reference values for additional cognitive measures, investigation of alternative thresholds for abnormality (including multi-test criteria), and validation in samples with more clinical endpoints are needed. (JINS, 2019, 25, 1-14).


Asunto(s)
Enfermedad de Alzheimer/prevención & control , Envejecimiento Cognitivo/fisiología , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/fisiopatología , Pruebas Neuropsicológicas , Sistema de Registros , Adulto , Anciano , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Valores de Referencia , Wisconsin
16.
J Int Neuropsychol Soc ; 25(2): 119-133, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30522545

RESUMEN

OBJECTIVES: Prior research has identified numerous genetic (including sex), education, health, and lifestyle factors that predict cognitive decline. Traditional model selection approaches (e.g., backward or stepwise selection) attempt to find one model that best fits the observed data, risking interpretations that only the selected predictors are important. In reality, several predictor combinations may fit similarly well but result in different conclusions (e.g., about size and significance of parameter estimates). In this study, we describe an alternative method, Information-Theoretic (IT) model averaging, and apply it to characterize a set of complex interactions in a longitudinal study on cognitive decline. METHODS: Here, we used longitudinal cognitive data from 1256 late-middle aged adults from the Wisconsin Registry for Alzheimer's Prevention study to examine the effects of sex, apolipoprotein E (APOE) ɛ4 allele (non-modifiable factors), and literacy achievement (modifiable) on cognitive decline. For each outcome, we applied IT model averaging to a set of models with different combinations of interactions among sex, APOE, literacy, and age. RESULTS: For a list-learning test, model-averaged results showed better performance for women versus men, with faster decline among men; increased literacy was associated with better performance, particularly among men. APOE had less of an association with cognitive performance in this age range (∼40-70 years). CONCLUSIONS: These results illustrate the utility of the IT approach and point to literacy as a potential modifier of cognitive decline. Whether the protective effect of literacy is due to educational attainment or intrinsic verbal intellectual ability is the topic of ongoing work. (JINS, 2019, 25, 119-133).


Asunto(s)
Disfunción Cognitiva/epidemiología , Alfabetización/estadística & datos numéricos , Modelos Teóricos , Sistema de Registros , Adulto , Anciano , Enfermedad de Alzheimer/prevención & control , Apolipoproteína E4/genética , Disfunción Cognitiva/genética , Escolaridad , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Factores Protectores , Factores Sexuales , Wisconsin/epidemiología
17.
Int J Gynecol Cancer ; 29(1): 102-107, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30640690

RESUMEN

OBJECTIVES: To determine if linear measurements of adiposity from pre-operative imaging can improve anticipation of surgical difficulty among endometrial cancer patients. METHODS: Eighty patients with newly diagnosed endometrial cancer were enrolled. Routine pre-operative imaging (MRI or CT) was performed. Radiologic linear measurements of the following were obtained: anterior-to-posterior skin distance; anterior skin to anterior edge of L5 distance (total anterior); anterior peritoneum to anterior edge of L5 distance (visceral obesity); and posterior edge of L5 to posterior skin distance (total posterior). Surgeons completed questionnaires quantifying preoperative anticipated operative difficulty and postoperative reported operative difficulty. The primary objective was to assess for a correlation between linear measurements of visceral fat and reported operative difficulty. RESULTS: Seventy-nine patients had questionnaires completed, preoperative imaging obtained, and surgery performed. Univariate analysis showed all four linear measurements, body mass index, weight, and anticipated operative difficulty were associated with increased reported operative difficulty (P< 0.05). Multivariate analysis demonstrated that body mass index and linear measurements visceral obesity and total posterior were independently associated with increased reported operative difficulty (P< 0.05). Compared with body mass index, the visceral obesity measurement was more sensitive and specific for predicting increased reported operative difficulty (visceral obesity; sensitivity 54%, specificity 91 %; body mass index; sensitivity 38%, specificity 89%). A difficulty risk model combining body mass index, visceral obesity, and total posterior demonstrated better predictive performance than any individual preoperative variable. CONCLUSIONS: Simple linear measurements of visceral fat obtained from preoperative imaging are more predictive than body mass index alone in anticipating surgeon-reported operative difficulty. These easily obtained measurements may assist in preoperative decision making in this challenging patient population.


Asunto(s)
Carcinosarcoma/diagnóstico por imagen , Cistadenocarcinoma Seroso/diagnóstico por imagen , Neoplasias Endometriales/diagnóstico por imagen , Grasa Intraabdominal/diagnóstico por imagen , Obesidad/complicaciones , Complicaciones Posoperatorias , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Carcinosarcoma/cirugía , Cistadenocarcinoma Seroso/cirugía , Neoplasias Endometriales/cirugía , Femenino , Estudios de Seguimiento , Humanos , Laparoscopía/métodos , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos
18.
Int Urogynecol J ; 29(7): 1051-1060, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29574484

RESUMEN

INTRODUCTION AND HYPOTHESIS: To determine the effectiveness of the muscarinic receptor antagonist solifenacin (VESIcare®) in the treatment of postvoid dribbling (PVD). METHODS: We carried out a multicenter, 12-week, double-blind, randomized, placebo-controlled, parallel design study. Between 2012 and 2015, a total of 118 women (age 18-89 years) with PVD at least twice/weekly, were randomized to receive solifenacin (5 mg; n = 58) or placebo (n = 60) once daily. The primary outcome was the percentage reduction in PVD episodes. Secondary outcomes included the percentage of patients with ≥50% reduction in PVD episodes and changes in quality of life. RESULTS: There were no differences in either the primary or secondary outcome variables. Subgroup analysis, based on those with more severe disease (>10 PVD episodes/week), showed a greater and significant percentage reduction in the frequency of PVD episodes per day (60.3% vs 32.1%; p = 0.035) and a higher percentage of patients showing ≥50% reduction in the frequency of PVD episodes with solifenacin (68.1% vs 45.8%; p = 0.0476). A significant solifenacin effect occurred at week 2 and continued through week 12 for the subgroup. For solifenacin, PVD reduction was the same for the entire cohort and subgroup, whereas for placebo, it was 10% lower in the subgroup, declining from 42% to 32%. CONCLUSION: There were no differences in PVD outcomes between the solifenacin and placebo groups. Solifenacin may play a role in treating women with the most severe symptoms. Because of the powerful placebo response seen in this study, behavior-based interventions may be useful for treating PVD.


Asunto(s)
Antagonistas Muscarínicos/uso terapéutico , Calidad de Vida/psicología , Succinato de Solifenacina/uso terapéutico , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Micción/efectos de los fármacos , Niño , Método Doble Ciego , Femenino , Humanos , Quinuclidinas , Resultado del Tratamiento , Vejiga Urinaria Hiperactiva/diagnóstico , Vejiga Urinaria Hiperactiva/psicología
19.
Bioethics ; 30(8): 597-600, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27369470

RESUMEN

Is it ethical to pay patients for selecting cheaper medical treatments? The healthcare system in the United States is notoriously profligate, at least in part because when insurers foot the bill, patients have little incentive to avoid wasteful treatments. One familiar means for dealing with this problem is for insurers to offer reduced co-pays to patients who select cheaper treatments. Would it be ethical to take this one step further, beyond the zero bound, sharing the savings of cheaper treatments by positively paying the patients who select them? Schmidt & Emanuel recently proposed this policy of 'Inclusive Shared Savings' (ISS). This article examines various ethical objections to the idea.


Asunto(s)
Ahorro de Costo , Ética Médica , Cobertura del Seguro , Seguro de Salud , Motivación , Pacientes/psicología , Conducta de Elección , Humanos , Estados Unidos
20.
Bioethics ; 30(3): 159-64, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26132886

RESUMEN

Bioethicists often present 'saving lives' as a goal distinct from, and competing with, that of extending lives by as much as possible. I argue that this usage of the term is misleading, and provides unwarranted rhetorical support for neglecting the magnitudes of the harms and benefits at stake in medical allocation decisions, often to the detriment of the young. Equal concern for all persons requires weighting equal interests equally, but not all individuals have an equal interest in 'life-saving' treatment.


Asunto(s)
Teoría Ética , Asignación de Recursos para la Atención de Salud/ética , Esperanza de Vida , Selección de Paciente/ética , Calidad de Vida , Años de Vida Ajustados por Calidad de Vida , Valor de la Vida , Beneficencia , Análisis Ético , Humanos , Valor de la Vida/economía
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