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1.
Health Sci Rep ; 5(6): e905, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36310758

RESUMO

Background and Aims: Considering the opposite outcome-for example, survival instead of death-may affect conclusions about which subpopulation benefits more from a treatment or suffers more from an exposure. Methods: For case studies on death following COVID-19 and bankruptcy following melanoma, we compute and interpret the relative risk, odds ratio, and risk difference for different age groups. Since there is no established effect measure or outcome for either study, we redo these analyses for survival and solvency. Results: In a case study on COVID-19 that ignores confounding, the relative risk of death suggested that 40-49-year-old Mexicans with COVID-19 suffered more from their unprepared healthcare system, using Italy's system as a baseline, than their 60-69-year-old counterparts. The relative risk of survival and the risk difference suggested the opposite conclusion. A similar phenomenon occurred in a case study on bankruptcy following melanoma treatment. Conclusion: To increase transparency around this paradox, researchers reporting one outcome should note if considering the opposite outcome would yield different conclusions. When possible, researchers should also report or estimate underlying risks alongside effect measures.

2.
Surgery ; 170(1): 13-17, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33714616

RESUMO

BACKGROUND: Since the 1990s, the number of bariatric surgeries has dramatically increased, including the number of bariatric centers in the United States; no recent studies have yet assessed trends of bariatric surgery. This study aims to assess the trends of bariatric surgery and the change in utilization by the type of surgery, from 2006 to 2015, using real-world data. METHODS: A cross-sectional analysis of MarketScan databases of privately insured beneficiaries aged equal to or more than 18 years, to assess the annual incidence rate of bariatric surgery type of surgery from 2006 to 2015. Linear regression analysis was used to assess the significance of bariatric surgery changes over time. RESULTS: A gradual increase in overall bariatric surgery was observed from 43.5 per 100,000 in 2006 to 70.6 per 100,000 in 2009. This increasing trend plateaued from 2010 to 2015. Among all bariatric surgeries performed, the sleeve gastrectomy showed a significant increase from (n = 596) 11% in 2006 to (n = 15,425) 70% in 2015 (P < .001), whereas there was a decrease in Roux-en-Y from (n = 10,129) 45% in 2010 to (n = 5074) 24% in 2015 (P < .001). CONCLUSION: Utilization of bariatric surgery showed a gradual increase in the first 5 years, with steady rates in the last 5 years of the study period. Sleeve gastrectomy and Roux-en-Y remain the most performed bariatric procedures. Laparoscopic surgery continues to dominate bariatric surgery compared with open surgery.


Assuntos
Cirurgia Bariátrica/tendências , Obesidade/cirurgia , Adolescente , Adulto , Idoso , Cirurgia Bariátrica/métodos , Cirurgia Bariátrica/estatística & dados numéricos , Estudos Transversais , Bases de Dados Factuais/estatística & dados numéricos , Bases de Dados Factuais/tendências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Estados Unidos/epidemiologia , Adulto Jovem
3.
Crit Care Explor ; 2(12): e0278, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33251517

RESUMO

Obtaining informed consent for commonly performed ICU procedures is often compromised by variability in communication styles and inadequate verbal descriptions of anatomic concepts. The objective of this study was to evaluate the efficacy of an audiovisual module in improving the baseline knowledge of ICU procedures among patients and their caregivers. DESIGN: Prospective, observational study. SETTING: Forty-eight-bed adult surgical ICU at a tertiary care center. SUBJECTS: Critically ill surgical patients and their legally authorized representatives. INTERVENTIONS: An audiovisual module describing eight commonly performed ICU procedures. MEASUREMENTS AND MAIN RESULTS: Fifty-nine subjects were enrolled and completed an 11-question pre- and postvideo test of knowledge regarding commonly performed ICU procedures and a brief satisfaction survey. Twenty-nine percent had a healthcare background. High school was the highest level of education for 37% percent of all subjects. Out of 11 questions on the ICU procedure knowledge test, subjects scored an average 8.0 ± 1.9 correct on the pretest and 8.4 ± 2.0 correct on the posttest (p = 0.055). On univariate logistic regression, having a healthcare background was a negative predictor of improved knowledge (odds ratio, 0.185; 95% CI, 0.045-0.765), indicating that those with a health background had a lower probability of improving their score on the posttest. Among subjects who did not have a healthcare background, scores increased from 7.7 ± 1.9 to 8.3 ± 2.1 (p = 0.019). Seventy-five percent of all subjects indicated that the video was easy to understand, and 70% believed that the video improved their understanding of ICU procedures. CONCLUSIONS: Audiovisual modules may improve knowledge and comprehension of commonly performed ICU procedures among critically ill patients and caregivers who have no healthcare background.

4.
Front Immunol ; 11: 1289, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670283

RESUMO

Older adults have significantly worse morbidity and mortality after severe trauma than younger cohorts. The competency of the innate immune response decreases with advancing age, especially after an inflammatory insult. Subsequent poor outcomes after trauma are caused in part by dysfunctional leukocytes derived from the host's hematopoietic stem and progenitor cells (HSPCs). Our objective was to analyze the bone marrow (BM) HSPC transcriptomic [mRNA and microRNA (miR)] responses to trauma in older and younger adults. BM was collected intraoperatively <9 days after initial injury from trauma patients with non-mild injury [ISS ≥ 9] or with shock (lactate ≥ 2, base deficit ≥ 5, MAP ≤ 65) who underwent operative fixation of a pelvic or long bone fracture. Samples were also analyzed based on age (<55 years and ≥55 years), ISS score and transfusion in the first 24 h, and compared to age/sex-matched controls from non-cancer elective hip replacement or purchased healthy younger adult human BM aspirates. mRNA and miR expression patterns were calculated from lineage-negative enriched HSPCs. 924 genes were differentially expressed in older trauma subjects vs. age/sex-matched controls, while 654 genes were differentially expressed in younger subjects vs. age/sex-matched control. Only 68 transcriptomic changes were shared between the two groups. Subsequent analysis revealed upregulation of transcriptomic pathways related to quantity, function, differentiation, and proliferation of HSPCs in only the younger cohort. miR expression differences were also identified, many of which were associated with cell cycle regulation. In summary, differences in the BM HSPC mRNA and miR expression were identified between older and younger adult trauma subjects. These differences in gene and miR expression were related to pathways involved in HSPC production and differentiation. These differences could potentially explain why older adult patients have a suboptimal hematopoietic response to trauma. Although immunomodulation of HSPCs may be a necessary consideration to promote host protective immunity after host injury, the age related differences further highlight that patients may require an age-defined medical approach with interventions that are specific to their transcriptomic and biologic response. Also, targeting the older adult miRs may be possible for interventions in this patient population.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , MicroRNAs/genética , RNA Mensageiro/genética , Transcriptoma , Ferimentos e Lesões/genética , Fatores Etários , Idoso , Biologia Computacional/métodos , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Genômica/métodos , Hematopoese , Humanos , Masculino , Pessoa de Meia-Idade , Interferência de RNA
6.
J Trauma Acute Care Surg ; 86(2): 260-267, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30489504

RESUMO

BACKGROUND: Associations among inflammatory cytokines, erythropoietin (EPO), and anemia in critically ill septic patients remain unclear. This study tested the hypothesis that elevated inflammatory cytokines and decreased EPO would be associated with iron-restricted anemia while accounting for operative blood loss, phlebotomy blood loss, and red blood cell (RBC) transfusion volume. METHODS: Prospective observational cohort study of 42 critically ill septic patients was conducted. Hemoglobin (Hb) at sepsis onset and hospital discharge were used to calculate ΔHb. Operative blood loss, phlebotomy blood loss, and RBC transfusion volume were used to calculate adjusted ΔHb (AdjΔHb) assuming that 300 mL RBC is equal to 1 g/dL Hb. Patients with AdjΔHb of greater than 0 (positive AdjΔHb, n = 18) were compared with patients with AdjΔHb of less than or equal to 0 (negative AdjΔHb, n = 24). RESULTS: Plasma tumor necrosis factor α, granulocyte colony-stimulating factor, interleukin (IL)-6, IL-8, EPO, erythrocyte mean corpuscular volume, and serum transferrin receptor were measured on days 0, 1, 4, 7, and 14. Patients with negative AdjΔHb had significantly higher day 14 levels of IL-6 (37.4 vs. 15.2 pg/mL, p < 0.05), IL-8 (39.1 vs. 18.2 pg/mL, p = 0.01), and granulocyte colony-stimulating factor (101.3 vs. 60.5 pg/mL, p = 0.01), but not EPO. On linear regression analysis, lower AdjΔHb was associated with higher day 14 levels of IL-6 (r = 0.22, p < 0.01), IL-8 (r = 0.10, p = 0.04), stromal cell-derived factor 1 (r = 0.14, p = 0.02), and tumor necrosis factor α (r = 0.13, p = 0.02), but not EPO. Patients with negative AdjΔHb had significantly lower mean corpuscular volume on days 4 (89.6 vs. 93.2 fL/cell, p = 0.04), 7 (92.3 vs. 94.9 fL/cell, p = 0.04), and 14 (92.1 vs. 96.0 fL/cell, p = 0.03) but similar serum transferrin receptor levels. CONCLUSION: Persistent elevation of inflammatory cytokines was associated with iron-restricted anemia among critically ill septic patients, occurring in the absence of systemic iron deficiency, independent of endogenous EPO. LEVEL OF EVIDENCE: Prognostic study, level II.


Assuntos
Anemia/metabolismo , Citocinas/metabolismo , Eritropoetina/metabolismo , Inflamação/metabolismo , Sepse/metabolismo , Idoso , Estado Terminal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
7.
J Trauma Acute Care Surg ; 85(2): 247-255, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29613958

RESUMO

BACKGROUND: Advancing age is a strong risk factor for adverse outcomes across multiple disease processes. However, septic surgical and trauma patients are unique in that they incur two or more inflammatory insults. The effects of advanced age on sepsis pathophysiology and outcomes remain unclear. METHODS: We performed a single-center, prospective observational cohort study of surgical intensive care unit patients with severe sepsis/septic shock. Peripheral blood was collected for genomic, cytokine, and biomarker analysis at 0.5 day, 1 day, 4 days, 7 days, 14 days, 21 days, and 28 days after sepsis onset. Based on sensitivity analysis, cohorts were defined as "young" (<55 years) and "aged" (≥55 years). We compared age-defined cohorts to determine differences in patient characteristics, biomarker profiles, and clinical outcomes. RESULTS: The cohort included 173 patients with severe sepsis (n = 93; 53.8%) or septic shock (n = 80; 46.2%), with a mean age of 60.9 (±14.5) years. Intra-abdominal sepsis was the leading source (n = 81; 46.8%), followed by necrotizing soft tissue infection (n = 33, 19.1%) and pneumonia (n = 30; 17.3%). Aged patients had a higher comorbidity burden, but were otherwise similar to the young cohort. The aged cohort had a higher severity of early physiologic derangement (median APACHE II, 23 vs. 18; p = 0.002), greater incidence of multiple organ failure (64.3% vs. 40.4%, p = 0.006), and hospital mortality (15.9% vs. 2.1%; p = 0.016). Six-month mortality was significantly higher in the aged cohort as compared with young cohort (31% vs. 9%; p = 0.003). Aged septic patients biomarker trajectories suggestive of persistent immunosuppression (absolute lymphocyte count, soluble programed death ligand-1) and catabolism (Urine 3MH-Cr ratio, insulin growth factor, IGF1BP3, albumin) out to 28 days after sepsis. CONCLUSION: Aged, critically ill surgical patients have greater organ dysfunction and incidence of adverse clinical outcomes after sepsis. Biomarker profiles suggest an immunophenotype of persistent immunosuppression and catabolism. Advanced age may necessitate novel therapeutic strategies to promote multisystem organ recovery and improve survival after sepsis. LEVEL OF EVIDENCE: Prognostic, level II.


Assuntos
Fatores Etários , Mortalidade Hospitalar , Imunidade Inata , Insuficiência de Múltiplos Órgãos/imunologia , Insuficiência de Múltiplos Órgãos/mortalidade , Choque Séptico/imunologia , Choque Séptico/mortalidade , APACHE , Adulto , Idoso , Biomarcadores/análise , Feminino , Florida , Humanos , Incidência , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
8.
J Trauma Acute Care Surg ; 84(2): 342-349, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29251709

RESUMO

BACKGROUND: A growing number of patients survive sepsis but remain chronically critically ill. We sought to define clinical outcomes and incidence of chronic critical illness (CCI) after sepsis and to determine whether selected biomarkers of inflammation, immunosuppression, and catabolism differ between these patients and those that rapidly recover (RAP). METHODS: This 3-year prospective observational cohort study (NCT02276417) evaluated 145 surgical intensive care unit patients with sepsis for the development of CCI (≥14 days of intensive care unit resource utilization with persistent organ dysfunction). Patient clinical demographics, outcomes, and serial serum/urine samples were collected for plasma protein and urinary metabolite analyses. RESULTS: Of 145 sepsis patients enrolled, 19 (13%) died during their hospitalization and 71 (49%) developed CCI. The CCI patients were significantly older (mean, 63 ± 15 vs. 58 ± 13 years, p = 0.006) and more likely to be discharged to long-term acute care facilities (32% vs. 3%, p < 0.0001), whereas those with RAP were more often discharged to home or a rehabilitation facility. Six-month mortality was significantly higher in CCI as compared with RAP cohort (37% vs. 2%; p < 0.01). Multivariate logistic regression modeling revealed delayed onset sepsis (>48 hours after admission; odds ratio [OR], 10.93; 95% confidence interval [CI], 4.15-28.82]), interfacility transfer (OR, 3.58; 95% CI, 1.43-8.96), vasopressor-dependent septic shock (OR, 3.75; 95% CI, 1.47-9.54), and Sequential Organ Failure Assessment score of 5 or greater at 72 hours (OR, 5.03; 95% CI, 2.00-12.62) as independent risk factors for the development of CCI. The CCI patients also demonstrated greater elevations in inflammatory cytokines (IL-6, IL-8, IL-10), and biomarker profiles are consistent with persistent immunosuppression (absolute lymphocyte count and soluble programmed death ligand 1) and catabolism (plasma insulin-like growth factor binding protein 3 and urinary 3-methylhistidine excretion). CONCLUSION: The development of CCI has become the predominant clinical trajectory in critically ill surgical patients with sepsis. These patients exhibit biomarker profiles consistent with an immunocatabolic phenotype of persistent inflammation, immunosuppression, and catabolism. LEVEL OF EVIDENCE: Prognostic, level II.


Assuntos
Benchmarking/métodos , Estado Terminal/epidemiologia , Unidades de Terapia Intensiva , Complicações Pós-Operatórias/epidemiologia , Sepse/epidemiologia , Doença Crônica , Feminino , Seguimentos , Humanos , Tolerância Imunológica , Incidência , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/imunologia , Prognóstico , Estudos Prospectivos , Fatores de Risco , Sepse/imunologia , Taxa de Sobrevida/tendências , Fatores de Tempo , Estados Unidos/epidemiologia
9.
BMJ Open ; 7(7): e015136, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28765125

RESUMO

INTRODUCTION: Sepsis is a common, costly and morbid cause of critical illness in trauma and surgical patients. Ongoing advances in sepsis resuscitation and critical care support strategies have led to improved in-hospital mortality. However, these patients now survive to enter state of chronic critical illness (CCI), persistent low-grade organ dysfunction and poor long-term outcomes driven by the persistent inflammation, immunosuppression and catabolism syndrome (PICS). The Sepsis and Critical Illness Research Center (SCIRC) was created to provide a platform by which the prevalence and pathogenesis of CCI and PICS may be understood at a mechanistic level across multiple medical disciplines, leading to the development of novel management strategies and targeted therapies. METHODS: Here, we describe the design, study cohort and standard operating procedures used in the prospective study of human sepsis at a level 1 trauma centre and tertiary care hospital providing care for over 2600 critically ill patients annually. These procedures include implementation of an automated sepsis surveillance initiative, augmentation of clinical decisions with a computerised sepsis protocol, strategies for direct exportation of quality-filtered data from the electronic medical record to a research database and robust long-term follow-up. ETHICS AND DISSEMINATION: This study has been registered at ClinicalTrials.gov, approved by the University of Florida Institutional Review Board and is actively enrolling subjects. Dissemination of results is forthcoming.


Assuntos
Cuidados Críticos/métodos , Estado Terminal , Complicações Pós-Operatórias/terapia , Sepse/terapia , Adulto , Idoso , Doença Crônica , Bases de Dados Factuais , Registros Eletrônicos de Saúde , Feminino , Instalações de Saúde , Humanos , Tolerância Imunológica , Inflamação/etiologia , Masculino , Metabolismo , Pessoa de Meia-Idade , Estudos Prospectivos , Projetos de Pesquisa , Sepse/complicações , Universidades
10.
Ann Surg ; 265(4): 827-834, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27163951

RESUMO

OBJECTIVE: We hypothesized that after sepsis in humans, MDSCs will be persistently increased, functionally immunosuppressive, and associated with adverse clinical outcomes. BACKGROUND: Cancer and sepsis have surprisingly similar immunologic responses and equally dismal long term consequences. In cancer, increased myeloid-derived suppressor cells (MDSCs) induce detrimental immunosuppression, but little is known about the role of MDSCs after sepsis. METHODS: Blood was obtained from 74 patients within 12 hours of severe sepsis/septic shock (SS/SS), and at set intervals out to 28 days, and also in 18 healthy controls. MDSCs were phenotyped for cell surface receptor expression and enriched by cell sorting. Functional and genome-wide expression analyses were performed. Multiple logistic regression analysis was conducted to determine if increased MDSC appearance was associated with in-hospital and long-term outcomes. RESULTS: After SS/SS, CD33CD11bHLA-DR MDSCs were dramatically increased out to 28 days (P < 0.05). When co-cultured with MDSCs from SS/SS patients, antigen-driven T-cell proliferation and TH1/TH2 cytokine production were suppressed (P < 0.05). Additionally, septic MDSCs had suppressed HLA gene expression and up-regulated ARG1 expression (P < 0.05). Finally, SS/SS patients with persistent increased percentages of blood MDSCs had increased nosocomial infections, prolonged intensive care unit stays, and poor functional status at discharge (P < 0.05). CONCLUSIONS: After SS/SS in humans, circulating MDSCs are persistently increased, functionally immunosuppressive, and associated with adverse outcomes. This novel observation warrants further studies. As observed in cancer immunotherapy, MDSCs could be a novel component in multimodality immunotherapy targeting detrimental inflammation and immunosuppression after SS/SS to improve currently observed dismal long-term outcomes.


Assuntos
Infecção Hospitalar/imunologia , Células Supressoras Mieloides/imunologia , Sepse/imunologia , Sepse/mortalidade , Adulto , Idoso , Estudos de Casos e Controles , Doença Crônica , Estudos de Coortes , Infecção Hospitalar/mortalidade , Feminino , Mortalidade Hospitalar/tendências , Humanos , Terapia de Imunossupressão , Masculino , Pessoa de Meia-Idade , Alta do Paciente/estatística & dados numéricos , Prognóstico , Medição de Risco , Sepse/fisiopatologia , Choque Séptico/imunologia , Choque Séptico/mortalidade , Choque Séptico/fisiopatologia , Análise de Sobrevida
12.
Am J Epidemiol ; 179(10): 1255-63, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24723000

RESUMO

Reasons for health disparities may include neighborhood-level factors, such as availability of health services, social norms, and environmental determinants, as well as individual-level factors. Investigating health inequalities using nationally or locally representative data often requires an approach that can accommodate a complex sampling design, in which individuals have unequal probabilities of selection into the study. The goal of the present article is to review and compare methods of estimating or accounting for neighborhood influences with complex survey data. We considered 3 types of methods, each generalized for use with complex survey data: ordinary regression, conditional likelihood regression, and generalized linear mixed-model regression. The relative strengths and weaknesses of each method differ from one study to another; we provide an overview of the advantages and disadvantages of each method theoretically, in terms of the nature of the estimable associations and the plausibility of the assumptions required for validity, and also practically, via a simulation study and 2 epidemiologic data analyses. The first analysis addresses determinants of repeat mammography screening use using data from the 2005 National Health Interview Survey. The second analysis addresses disparities in preventive oral health care using data from the 2008 Florida Behavioral Risk Factor Surveillance System Survey.


Assuntos
Simulação por Computador , Disparidades nos Níveis de Saúde , Modelos Estatísticos , Saúde Bucal/estatística & dados numéricos , Características de Residência/estatística & dados numéricos , Idoso , Feminino , Comportamentos Relacionados com a Saúde , Nível de Saúde , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , Estados Unidos/epidemiologia
13.
Cancer Epidemiol Biomarkers Prev ; 20(11): 2331-44, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21914839

RESUMO

BACKGROUND: Despite a considerable number of studies describing the relationship between area-level socioeconomic conditions and mammography screening, definitive conclusions have yet to be drawn. The aim of this study was to examine the relationship between area-level socioeconomic position (SEP) and repeat mammography screening, using nationwide U.S. census SEP data linked to a nationally representative sample of women who participated in the 2005 National Health Interview Survey (NHIS). METHODS: An area-level SEP index using 2000 U.S. census tract data was constructed and categorized into quartiles, including information on unemployment, poverty, housing values, annual family income, education, and occupation. Repeat mammography utilization (dichotomous variable) was defined as having three mammograms over the course of 6 years (24-month interval), which must have included a recent mammogram (in past 2 years). Results were obtained by ordinary multivariable logistic regression for survey data. Women ages 46 to 79 years (n = 7,352) were included in the analysis. RESULTS: In a model adjusted for sociodemographics, health care factors, and known correlates of mammography screening, women living in more disadvantaged areas had lower odds of engaging in repeat mammography than women living in the most advantaged areas [OR comparing quartile 4 (most disadvantaged) to quartile 1 (most advantaged) = 0.63; 95% confidence interval, 0.50-0.80]. CONCLUSION: The results of this nationwide study support the hypothesis that area-level SEP is independently associated with mammography utilization. IMPACT: These findings underscore the importance of addressing area-level social inequalities, if uptake of mammography screening guidelines is to be realized across all social strata.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/economia , Mamografia/economia , Mamografia/estatística & dados numéricos , Idoso , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/prevenção & controle , Detecção Precoce de Câncer/economia , Detecção Precoce de Câncer/estatística & dados numéricos , Feminino , Inquéritos Epidemiológicos , Humanos , Modelos Logísticos , Programas de Rastreamento/economia , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Cooperação do Paciente , Fatores Socioeconômicos
14.
Stat Med ; 29(18): 1890-9, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20680982

RESUMO

In social epidemiology, one often considers neighborhood or contextual effects on health outcomes, in addition to effects of individual exposures. This paper is concerned with the estimation of an individual exposure effect in the presence of confounding by neighborhood effects, motivated by an analysis of National Health Interview Survey (NHIS) data. In the analysis, we operationalize neighborhood as the secondary sampling unit of the survey, which consists of small groups of neighboring census blocks. Thus the neighborhoods are sampled with unequal probabilities, as are individuals within neighborhoods. We develop and compare several approaches for the analysis of the effect of dichotomized individual-level education on the receipt of adequate mammography screening. In the analysis, neighborhood effects are likely to confound the individual effects, due to such factors as differential availability of health services and differential neighborhood culture. The approaches can be grouped into three broad classes: ordinary logistic regression for survey data, with either no effect or a fixed effect for each cluster; conditional logistic regression extended for survey data; and generalized linear mixed model (GLMM) regression for survey data. Standard use of GLMMs with small clusters fails to adjust for confounding by cluster (e.g. neighborhood); this motivated us to develop an adaptation. We use theory, simulation, and analyses of the NHIS data to compare and contrast all of these methods. One conclusion is that all of the methods perform poorly when the sampling bias is strong; more research and new methods are clearly needed.


Assuntos
Fatores de Confusão Epidemiológicos , Inquéritos Epidemiológicos/estatística & dados numéricos , Modelos Logísticos , Humanos , Modelos Lineares , Características de Residência
15.
J Clin Oncol ; 28(24): 3808-15, 2010 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-20660830

RESUMO

PURPOSE: Single-agent topotecan (TOPO) and combination topotecan and cyclophosphamide (TOPO/CTX) were compared in a phase II randomized trial in relapsed/refractory neuroblastoma. Because responders often underwent further therapies, novel statistical methods were required to compare the long-term outcome of the two treatments. PATIENTS AND METHODS: Children with refractory/recurrent neuroblastoma (only one prior aggressive chemotherapy regimen) were randomly assigned to daily 5-day topotecan (2 mg/m(2)) or combination topotecan (0.75 mg/m(2)) and cyclophosphamide (250 mg/m(2)). A randomized two-stage group sequential design enrolled 119 eligible patients. Toxicity and response were estimated. Long-term outcome of protocol therapy was assessed using novel methods-causal inference-which allowed adjustment for the confounding effect of off-study therapies. RESULTS: Seven more responses were observed for TOPO/CTX (complete response [CR] plus partial response [PR], 18 [32%] of 57) than TOPO (CR+PR, 11 [19%] of 59;P = .081); toxicity was similar. At 3 years, progression-free survival (PFS) and overall survival (OS) were 4% +/- 2% and 15% +/- 4%, respectively. PFS was significantly better for TOPO/CTX (P = .029); there was no difference in OS. Older age at diagnosis and lack of MYCN amplification predicted increased OS (P < .05). Adjusting for randomized treatment effect and subsequent autologous stem-cell transplantation, there was no difference between TOPO and TOPO/CTX in terms of the proportion alive at 2 years. CONCLUSION: TOPO/CTX was superior to TOPO in terms of PFS, but there was no OS difference. After adjustment for subsequent therapies, no difference was detected in the proportion alive at 2 years. Causal inference methods for assessing long-term outcomes of phase II therapies after subsequent treatment can elucidate effects of initial therapies.


Assuntos
Antineoplásicos/uso terapêutico , Ciclofosfamida/administração & dosagem , Modelos Estatísticos , Neuroblastoma/tratamento farmacológico , Topotecan/administração & dosagem , Adolescente , Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Causalidade , Criança , Pré-Escolar , Fatores de Confusão Epidemiológicos , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Prognóstico , Recidiva , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
16.
Clin Cancer Res ; 13(11): 3191-7, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17545522

RESUMO

PURPOSE: Epigenetic aberrations have been shown to play an important role in the pathogenesis of most cancers. To investigate the clinical significance of epigenetic changes in neuroblastoma, we evaluated the relationship between clinicopathologic variables and the pattern of gene methylation in neuroblastoma cell lines and tumors. EXPERIMENTAL DESIGN: Methylation-specific PCR was used to evaluate the gene methylation status of 19 genes in 14 neuroblastoma cell lines and 8 genes in 70 primary neuroblastoma tumors. Associations between gene methylation, established prognostic factors, and outcome were evaluated. Log-rank tests were used to identify the number of methylated genes that was most predictive of overall survival. RESULTS: Epigenetic changes were detected in the neuroblastoma cell lines and primary tumors, although the pattern of methylation varied. Eight of the 19 genes analyzed were methylated in >70% of the cell lines. Epigenetic changes of four genes were detected in only small numbers of cell lines. None of the cell lines had methylation of the other seven genes analyzed. In primary neuroblastoma tumors, high-risk disease and poor outcome were associated with methylation of DCR2, CASP8, and HIN-1 individually. Although methylation of the other five individual genes was not predictive of poor outcome, a trend toward decreased survival was seen in patients with a methylation phenotype, defined as > or =4 methylated genes (P = 0.055). CONCLUSION: Our study indicates that clinically aggressive neuroblastoma tumors have aberrant methylation of multiple genes and provides a rationale for exploring treatment strategies that include demethylating agents.


Assuntos
Caspase 8/biossíntese , Citocinas/biossíntese , Regulação Neoplásica da Expressão Gênica , Metilação , Neuroblastoma/metabolismo , Receptores Chamariz do Fator de Necrose Tumoral/biossíntese , Proteínas Supressoras de Tumor/biossíntese , Caspase 8/genética , Linhagem Celular Tumoral , Estudos de Coortes , Citocinas/genética , Epigênese Genética , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Resultado do Tratamento , Receptores Chamariz do Fator de Necrose Tumoral/genética , Proteínas Supressoras de Tumor/genética
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