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1.
N Engl J Med ; 381(6): 520-530, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31173679

RESUMO

BACKGROUND: Observational studies support an association between a low blood 25-hydroxyvitamin D level and the risk of type 2 diabetes. However, whether vitamin D supplementation lowers the risk of diabetes is unknown. METHODS: We randomly assigned adults who met at least two of three glycemic criteria for prediabetes (fasting plasma glucose level, 100 to 125 mg per deciliter; plasma glucose level 2 hours after a 75-g oral glucose load, 140 to 199 mg per deciliter; and glycated hemoglobin level, 5.7 to 6.4%) and no diagnostic criteria for diabetes to receive 4000 IU per day of vitamin D3 or placebo, regardless of the baseline serum 25-hydroxyvitamin D level. The primary outcome in this time-to-event analysis was new-onset diabetes, and the trial design was event-driven, with a target number of diabetes events of 508. RESULTS: A total of 2423 participants underwent randomization (1211 to the vitamin D group and 1212 to the placebo group). By month 24, the mean serum 25-hydroxyvitamin D level in the vitamin D group was 54.3 ng per milliliter (from 27.7 ng per milliliter at baseline), as compared with 28.8 ng per milliliter in the placebo group (from 28.2 ng per milliliter at baseline). After a median follow-up of 2.5 years, the primary outcome of diabetes occurred in 293 participants in the vitamin D group and 323 in the placebo group (9.39 and 10.66 events per 100 person-years, respectively). The hazard ratio for vitamin D as compared with placebo was 0.88 (95% confidence interval, 0.75 to 1.04; P = 0.12). The incidence of adverse events did not differ significantly between the two groups. CONCLUSIONS: Among persons at high risk for type 2 diabetes not selected for vitamin D insufficiency, vitamin D3 supplementation at a dose of 4000 IU per day did not result in a significantly lower risk of diabetes than placebo. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others; D2d ClinicalTrials.gov number, NCT01942694.).


Assuntos
Colecalciferol/uso terapêutico , Diabetes Mellitus Tipo 2/prevenção & controle , Suplementos Nutricionais , Estado Pré-Diabético/tratamento farmacológico , Vitaminas/uso terapêutico , Administração Oral , Idoso , Colecalciferol/administração & dosagem , Intervalo Livre de Doença , Método Duplo-Cego , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estado Pré-Diabético/sangue , Fatores de Risco , Falha de Tratamento , Vitamina D/análogos & derivados , Vitamina D/sangue , Vitaminas/administração & dosagem
2.
J Biopharm Stat ; 27(5): 797-808, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28166460

RESUMO

We evaluate properties of sample size re-estimation (SSR) designs similar to the promising zone design considered by Mehta and Pocock (2011). We evaluate these designs under the assumption of a true effect size of 1.1 down to 0.4 of the protocol-specified effect size by six measures: 1. The probability of a sample size increase, 2. The mean proportional increase in sample size given an increase; 3 and 4. The mean true conditional power with and without a sample size increase; 5 and 6. The expected increase in sample size and power due to the SSR procedure. These measures show the probability of a sample size increase and the cost/benefit for given true effect sizes, particularly when the SSR may either be pursuing a small effect size of little clinical importance or be unnecessary when the true effect size is close to the protocol-specified effect size. The results show the clear superiority of conducting the SSR late in the study and the inefficiency of a mid-study SSR. The results indicate that waiting until late in the study for the SSR yields a smaller, better targeted set of studies with a greater increase in overall power than a mid-study SSR.


Assuntos
Pesquisa Biomédica/estatística & dados numéricos , Tamanho da Amostra , Modificador do Efeito Epidemiológico , Humanos
3.
PLoS Med ; 13(6): e1002038, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27327774

RESUMO

BACKGROUND: Under-five mortality is declining in Ghana and many other countries. Very few studies have measured under-five mortality-and its social and environmental risk factors-at fine spatial resolutions, which is relevant for policy purposes. Our aim was to estimate under-five mortality and its social and environmental risk factors at the district level in Ghana. METHODS AND FINDINGS: We used 10% random samples of Ghana's 2000 and 2010 National Population and Housing Censuses. We applied indirect demographic methods and a Bayesian spatial model to the information on total number of children ever born and children surviving to estimate under-five mortality (probability of dying by 5 y of age, 5q0) for each of Ghana's 110 districts. We also used the census data to estimate the distributions of households or persons in each district in terms of fuel used for cooking, sanitation facility, drinking water source, and parental education. Median district 5q0 declined from 99 deaths per 1,000 live births in 2000 to 70 in 2010. The decline ranged from <5% in some northern districts, where 5q0 had been higher in 2000, to >40% in southern districts, where it had been lower in 2000, exacerbating existing inequalities. Primary education increased in men and women, and more households had access to improved water and sanitation and cleaner cooking fuels. Higher use of liquefied petroleum gas for cooking was associated with lower 5q0 in multivariate analysis. CONCLUSIONS: Under-five mortality has declined in all of Ghana's districts, but the cross-district inequality in mortality has increased. There is a need for additional data, including on healthcare, and additional environmental and socioeconomic measurements, to understand the reasons for the variations in mortality levels and trends.


Assuntos
Mortalidade da Criança , Mortalidade Infantil , Fatores Socioeconômicos , Teorema de Bayes , Censos , Pré-Escolar , Feminino , Geografia , Gana , Humanos , Lactente , Recém-Nascido , Masculino , Fatores de Risco
7.
Am J Ther ; 20(3): 235-46, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23615317

RESUMO

Smoking is a major modifiable risk factor for cardiovascular (CV) disease. Varenicline is a pharmacological aid for smoking cessation. To explore the CV safety of varenicline, we investigated the incidence of CV events in varenicline-treated subjects across all phase 2-4 randomized placebo-controlled clinical trials of ≥12-week treatment duration conducted in smokers aged ≥18 years and sponsored by the drug manufacturer. This manuscript reports a subject-level meta-analysis of time to major adverse cardiovascular events (MACE; defined as CV-related death, nonfatal myocardial infarction, nonfatal stroke) and time to MACE+ (defined as MACE plus worsening or any procedure for peripheral vascular disease, hospitalization for angina, or performance of coronary revascularization). All events were adjudicated by an independent adjudication committee, blind to treatment assignment. Events were assessed during treatment and up to 30 days after the last treatment dose. The primary analytical method was a stratified logrank time-to-event analysis; secondary analyses were meta-analyses of incidence rate ratios and rate differences. Overall, 7002 subjects were included (varenicline: 4190; placebo: 2812) from 15 studies. MACE were reported by 13 varenicline subjects (0.31%) and 6 placebo subjects (0.21%) [hazard ratio, 1.95; 95% confidence interval (CI): 0.79-4.82; P = 0.15; risk difference, 0.006 events per subject-year; 95% CI: -0.003, 0.015, P = 0.19]. MACE+ were reported by 26 varenicline subjects (0.62%) and 12 placebo subjects (0.43%) (hazard ratio, 1.74; 95% CI: 0.91-3.34, P = 0.10; risk difference, 0.010; 95% CI: -0.002, 0.022, P = 0.11). This subject-level meta-analysis of MACE or MACE+ up to 30 days posttreatment in placebo-controlled clinical trials of varenicline found a trend toward increased incidence of these events in varenicline-treated patients that did not reach statistical significance. The overall number of events was low and the absolute risk of CV events with varenicline was small.


Assuntos
Benzazepinas/efeitos adversos , Doenças Cardiovasculares/induzido quimicamente , Agonistas Nicotínicos/efeitos adversos , Quinoxalinas/efeitos adversos , Abandono do Hábito de Fumar/métodos , Angina Instável/induzido quimicamente , Angina Instável/epidemiologia , Angina Instável/terapia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/terapia , Método Duplo-Cego , Humanos , Incidência , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/epidemiologia , Doenças Vasculares Periféricas/induzido quimicamente , Doenças Vasculares Periféricas/epidemiologia , Doenças Vasculares Periféricas/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Acidente Vascular Cerebral/induzido quimicamente , Acidente Vascular Cerebral/epidemiologia , Resultado do Tratamento , Vareniclina
8.
Prev Sci ; 14(2): 111-20, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21562742

RESUMO

In the analysis of prevention and intervention studies, it is often important to investigate whether treatment effects vary among subgroups of patients defined by individual characteristics. These "subgroup analyses" can provide information about how best to use a new prevention or intervention program. However, subgroup analyses can be misleading if they test data-driven hypotheses, employ inappropriate statistical methods, or fail to account for multiple testing. These problems have led to a general suspicion of findings from subgroup analyses. This article discusses sound methods for conducting subgroup analyses to detect moderators. Multiple authors have argued that, to assess whether a treatment effect varies across subgroups defined by patient characteristics, analyses should be based on tests for interaction rather than treatment comparisons within the subgroups. We discuss the concept of heterogeneity and its dependence on the metric used to describe treatment effects. We discuss issues of multiple comparisons related to subgroup analyses and the importance of considering multiplicity in the interpretation of results. We also discuss the types of questions that would lead to subgroup analyses and how different scientific goals may affect the study at the design stage. Finally, we discuss subgroup analyses based on post-baseline factors and the complexity associated with this type of subgroup analysis.


Assuntos
Variações Dependentes do Observador , Serviços Preventivos de Saúde/organização & administração , Humanos
9.
J Pediatr ; 159(5): 743-749.e1-2, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21658712

RESUMO

OBJECTIVE: To measure the changes in whole blood fatty acid levels in premature infants and evaluate associations between these changes and neonatal morbidities. STUDY DESIGN: This was a retrospective cohort study of 88 infants born at <30 weeks' gestation. Serial fatty acid profiles during the first postnatal month and infant outcomes, including chronic lung disease (CLD), retinopathy of prematurity, and late-onset sepsis, were analyzed. Regression modeling was applied to determine the association between fatty acid levels and neonatal morbidities. RESULTS: Docosahexaenoic acid (DHA) and arachidonic acid levels declined rapidly in the first postnatal week, with a concomitant increase in linoleic acid levels. Decreased DHA level was associated with an increased risk of CLD (OR, 2.5; 95% CI, 1.3-5.0). Decreased arachidonic acid level was associated with an increased risk of late-onset sepsis (hazard ratio, 1.4; 95% CI, 1.1-1.7). The balance of fatty acids was also a predictor of CLD and late-onset sepsis. An increased linoleic acid:DHA ratio was associated with an increased risk of CLD (OR, 8.6; 95% CI, 1.4-53.1) and late-onset sepsis (hazard ratio, 4.6; 95% CI, 1.5-14.1). CONCLUSION: Altered postnatal fatty acid levels in premature infants are associated with an increased risk of CLD and late-onset sepsis.


Assuntos
Ácido Araquidônico/sangue , Ácidos Docosa-Hexaenoicos/sangue , Recém-Nascido Prematuro/sangue , Pneumopatias/sangue , Doença Crônica , Estudos de Coortes , Ácidos Graxos/sangue , Feminino , Humanos , Recém-Nascido , Pneumopatias/epidemiologia , Masculino , Oxigenoterapia , Modelos de Riscos Proporcionais , Retinopatia da Prematuridade/sangue , Retinopatia da Prematuridade/epidemiologia , Estudos Retrospectivos , Sepse/sangue , Sepse/epidemiologia
10.
Occup Environ Med ; 68(4): 279-85, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20935283

RESUMO

OBJECTIVES: Slips and falls are a leading cause of injury at work. Few studies, however, have systematically examined risk factors of slipping outside the laboratory environment. This study examined the association between floor surface characteristics, slip-resistant shoes, floor cleaning frequency and the risk of slipping in limited-service restaurant workers. METHODS: 475 workers from 36 limited-service restaurants from three major chains in six states in the USA were recruited to participate in a prospective cohort study of workplace slipping. Kitchen floor surface roughness and coefficient of friction (COF) were measured in eight working areas and then averaged within each restaurant. The use of slip-resistant shoes was determined by examining the participant's shoes and noting the presence of a 'slip-resistant' marking on the sole. Restaurant managers reported the frequency of daily kitchen floor cleaning. Participants reported their slip experience and work hours weekly for up to 12 weeks. The survey materials were made available in three languages: English, Spanish and Portuguese. The associations between rate of slipping and risk factors were assessed using a multivariable negative binomial generalised estimating equation model. RESULTS: The mean of individual slipping rate varied among the restaurants from 0.02 to 2.49 slips per 40 work hours. After adjusting for age, gender, BMI, education, primary language, job tenure and restaurant chain, the use of slip-resistant shoes was associated with a 54% reduction in the reported rate of slipping (95% CI 37% to 64%), and the rate of slipping decreased by 21% (95% CI 5% to 34%) for each 0.1 increase in the mean kitchen COF. Increasing floor cleaning frequency was significantly associated with a decreasing rate of slipping when considered in isolation but not after statistical adjustment for other factors. CONCLUSION: These results provide support for the use of slip-resistant shoes and measures to increase COF as preventive interventions to reduce slips, falls and injuries.


Assuntos
Acidentes por Quedas/prevenção & controle , Acidentes de Trabalho/prevenção & controle , Pisos e Cobertura de Pisos/estatística & dados numéricos , Restaurantes/estatística & dados numéricos , Sapatos , Acidentes por Quedas/estatística & dados numéricos , Acidentes de Trabalho/estatística & dados numéricos , Adolescente , Adulto , Idoso , Planejamento Ambiental , Feminino , Fricção , Humanos , Higiene , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Gestão da Segurança/métodos , Propriedades de Superfície , Estados Unidos , Adulto Jovem
11.
Occup Environ Med ; 68(8): 575-81, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21097951

RESUMO

OBJECTIVES: This nested case-crossover study examined the association between rushing, distraction and walking on a contaminated floor and the rate of slipping, and whether the effects varied according to weekly hours worked, job tenure and use of slip-resistant shoes. METHODS: At baseline, workers from 30 limited-service restaurants in the USA reported average work hours, average weekly duration of exposure to each transient risk factor and job tenure at the current location. Use of slip-resistant shoes was determined. During the following 12 weeks, participants reported weekly their slip experience and exposures to the three transient exposures at the time of slipping. The case-crossover design was used to estimate the rate ratios using the Mantel-Haenszel estimator for person-time data. RESULTS: Among 396 participants providing baseline information, 210 reported one or more slips with a total of 989 slips. Rate of slipping was 2.9 times higher when rushing as compared to working at a normal pace (95% CI 2.5 to 3.3). Rate of slipping was also significantly increased by distraction (rate ratio (RR) 1.7, 95% CI 1.5 to 2.0) and walking on a contaminated floor (RR 14.6, 95% CI 12.6 to 17.0). Use of slip-resistant shoes decreased the effects of rushing and walking on a contaminated floor. Rate ratios for all three transient factors decreased monotonically as job tenure increased. CONCLUSION: The results suggest the importance of these transient risk factors, particularly floor contamination, on rate of slipping in limited-service restaurant workers. Stable characteristics, such as slip-resistant shoes, reduced the effects of transient exposures.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Acidentes de Trabalho/estatística & dados numéricos , Restaurantes/estatística & dados numéricos , Adolescente , Adulto , Atenção , Métodos Epidemiológicos , Feminino , Pisos e Cobertura de Pisos , Humanos , Masculino , Pessoa de Meia-Idade , Admissão e Escalonamento de Pessoal/estatística & dados numéricos , Sapatos , Propriedades de Superfície , Estados Unidos/epidemiologia , Adulto Jovem
12.
Ann Neurol ; 65(4): 386-93, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19399887

RESUMO

OBJECTIVE: Randomized, blinded trial of intramuscular gene transfer using plasmid vascular endothelial growth factor (VEGF) to treat diabetic polyneuropathy. METHODS: Diabetic patients with polyneuropathy were randomized to receive a VEGF-to-placebo ratio of 3:1. Three sets of injections were given at eight standardized sites adjacent to the sciatic, peroneal, and tibial nerves of one leg. Primary outcomes were change in symptom score at 6 months and a prespecified overall clinical and electrophysiological improvement score. Secondary outcomes were differences in symptoms, examination scores, visual analog pain scale, nerve conduction, and quantitative sensory testing. RESULTS: Thirty-nine patients received plasmid VEGF and 11 received placebo. Mean symptom score improved in both legs at 6 months, favoring VEGF over placebo (-1.2 +/- 0.5 vs -0.9 +/- 0.5; p < 0.01 after adjustment for change in the untreated leg) and compared with the untreated leg (-0.7 +/- 0.5; p = 0.02). The region of sensory loss and visual analog pain scale improved in the treated group (-1.5 vs -0.5; p = 0.01). Twelve of 39 VEGF versus 2 of 11 placebo patients met criterion for overall improvement. Other measures including nerve conduction potentials did not improve. There were 84 adverse events in VEGF patients, and 22 were serious; there were 51 events in placebo patients, and 2 were serious. INTERPRETATION: Intramuscular plasmid VEGF gene transfer improved diabetic neuropathic symptoms, meeting primary end-point criteria for efficacy but not affecting most secondary measures. Treatment was associated with more serious adverse events that did not reach statistical significance. These results are not conclusive but may justify further clinical study.


Assuntos
Neuropatias Diabéticas/terapia , Técnicas de Transferência de Genes , Terapia Genética/métodos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Idoso , Estudos de Coortes , Neuropatias Diabéticas/metabolismo , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/genética , Medição da Dor , Nervos Periféricos/fisiopatologia , Índice de Gravidade de Doença , Resultado do Tratamento
13.
Respirology ; 15(6): 881-5; discussion 885-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20624253

RESUMO

There is controversy regarding the possibility that long-acting beta-agonists (LABA) may paradoxically contribute adversely to asthma mortality. While studies and meta-analyses indicate increased risk, epidemiological data indicate a slow fall in asthma mortality since the introduction of LABA. Advocates for LABA propose that mandatory simultaneous use of inhaled corticosteroids satisfactorily reduce any potential risk. In the face of lingering doubts, others propose that LABA should be withdrawn from use. In this pro-con article, Kazani et al. provide the rationale for a modified randomized controlled trial that would define the level of risk more clearly, and provide the basis for a clear judgment to be made. Sears argues that current knowledge about the risks associated with LABA, especially when prescribed as monotherapy, provides sufficient evidence for clinicians and licensing authorities alike, and that the logistics and likely outcomes for a large prospective study are unjustified.


Assuntos
Agonistas Adrenérgicos beta/efeitos adversos , Asma/tratamento farmacológico , Corticosteroides/uso terapêutico , Agonistas Adrenérgicos beta/uso terapêutico , Antiasmáticos/uso terapêutico , Asma/mortalidade , Humanos , Metanálise como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Eur Heart J ; 30(12): 1457-66, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19351691

RESUMO

AIMS: To evaluate the associations of myocardial infarction (MI) and major bleeding with 1-year mortality. Both MI and major bleeding predict 1-year mortality in patients presenting with acute coronary syndrome (ACS). However, the risk of each of these events on the magnitude and timing of mortality has not been well studied. METHODS AND RESULTS: A multivariable Cox regression model was developed relating 13 independent baseline predictors to 1-year mortality for 13 819 patients with moderate and high-risk ACS enrolled in the Acute Catheterization and Urgent Intervention Triage strategy trial. After adjustment for baseline predictors, Cox models with major bleeding and recurrent MI as time-updated covariates estimated the effect of these events on mortality hazard over time. Within 30 days of randomization, 705 patients (5.1%) had an MI, 645 (4.7%) had a major bleed; 524 (3.8%) died within a year. The occurrence of an MI was associated with a hazard ratio of 3.1 compared with patients not yet having an MI, after adjustment for baseline predictors. However, MI within 30 days markedly increased the mortality risk for the first 2 days after the event (adjusted hazard ratio of 17.6), but this risk declined rapidly post-infarct (hazard ratio of 1.4 beyond 1 month after the MI event). In contrast, major bleeding had a prolonged association with mortality risk (hazard ratio of 3.5) which remained fairly steady over time throughout 1 year. CONCLUSION: After accounting for baseline predictors of mortality, major bleeds and MI have similar overall strength of association with mortality in the first year after ACS. MI is correlated with a dramatic increase in short-term risk, whereas major bleeding correlates with a more prolonged mortality risk.


Assuntos
Síndrome Coronariana Aguda/mortalidade , Hemorragia/mortalidade , Infarto do Miocárdio/mortalidade , Síndrome Coronariana Aguda/tratamento farmacológico , Idoso , Angiografia Coronária , Creatina Quinase Forma MB/sangue , Métodos Epidemiológicos , Feminino , Hemorragia/complicações , Hemorragia/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/terapia , Terapia Trombolítica/métodos , Fatores de Tempo , Troponina/sangue
16.
N Engl J Med ; 355(21): 2203-16, 2006 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-17124018

RESUMO

BACKGROUND: Current guidelines for patients with moderate- or high-risk acute coronary syndromes recommend an early invasive approach with concomitant antithrombotic therapy, including aspirin, clopidogrel, unfractionated or low-molecular-weight heparin, and glycoprotein IIb/IIIa inhibitors. We evaluated the role of thrombin-specific anticoagulation with bivalirudin in such patients. METHODS: We assigned 13,819 patients with acute coronary syndromes to one of three antithrombotic regimens: unfractionated heparin or enoxaparin plus a glycoprotein IIb/IIIa inhibitor, bivalirudin plus a glycoprotein IIb/IIIa inhibitor, or bivalirudin alone. The primary end points were a composite ischemia end point (death, myocardial infarction, or unplanned revascularization for ischemia), major bleeding, and the net clinical outcome, defined as the combination of composite ischemia or major bleeding. RESULTS: Bivalirudin plus a glycoprotein IIb/IIIa inhibitor, as compared with heparin plus a glycoprotein IIb/IIIa inhibitor, was associated with noninferior 30-day rates of the composite ischemia end point (7.7% and 7.3%, respectively), major bleeding (5.3% and 5.7%), and the net clinical outcome end point (11.8% and 11.7%). Bivalirudin alone, as compared with heparin plus a glycoprotein IIb/IIIa inhibitor, was associated with a noninferior rate of the composite ischemia end point (7.8% and 7.3%, respectively; P=0.32; relative risk, 1.08; 95% confidence interval [CI], 0.93 to 1.24) and significantly reduced rates of major bleeding (3.0% vs. 5.7%; P<0.001; relative risk, 0.53; 95% CI, 0.43 to 0.65) and the net clinical outcome end point (10.1% vs. 11.7%; P=0.02; relative risk, 0.86; 95% CI, 0.77 to 0.97). CONCLUSIONS: In patients with moderate- or high-risk acute coronary syndromes who were undergoing invasive treatment with glycoprotein IIb/IIIa inhibitors, bivalirudin was associated with rates of ischemia and bleeding that were similar to those with heparin. Bivalirudin alone was associated with similar rates of ischemia and significantly lower rates of bleeding. (ClinicalTrials.gov number, NCT00093158 [ClinicalTrials.gov].).


Assuntos
Angina Instável/tratamento farmacológico , Anticoagulantes/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Angina Instável/terapia , Angioplastia Coronária com Balão , Anticoagulantes/efeitos adversos , Ponte de Artéria Coronária , Quimioterapia Combinada , Enoxaparina/uso terapêutico , Feminino , Hemorragia/induzido quimicamente , Heparina/uso terapêutico , Hirudinas/efeitos adversos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/epidemiologia , Fragmentos de Peptídeos/efeitos adversos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico
17.
Lancet ; 369(9565): 907-19, 2007 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-17368152

RESUMO

BACKGROUND: The aim of this study was to assess anticoagulation with the direct thrombin inhibitor bivalirudin during percutaneous coronary intervention in individuals with moderate and high-risk acute coronary syndromes. METHODS: 13,819 individuals in the Acute Catheterization and Urgent Intervention Triage strategy (ACUITY) trial were prospectively randomly assigned to receive heparin (unfractionated or enoxaparin) plus glycoprotein IIb/IIIa inhibitors, bivalirudin plus glycoprotein IIb/IIIa inhibitors, or bivalirudin alone. Of these individuals, 7789 underwent percutaneous coronary intervention after angiography. The effect of the three regimens on the primary 30-day endpoints of composite ischaemia (death, myocardial infarction, or unplanned revascularisation for ischaemia), major bleeding, and net clinical outcomes (composite ischaemia or major bleeding) was assessed in this subgroup. Analyses were done by intention to treat. This trial is registered with ClinicalTrials.gov, with the number NCT00093158. FINDINGS: Of the individuals who underwent percutaneous coronary intervention, 2561 received heparin plus glycoprotein IIb/IIIa inhibitors, 2609 received bivalirudin plus glycoprotein IIb/IIIa inhibitors, and 2619 received bivalirudin alone. 26 (0.3%) individuals dropped out or were lost to follow-up. There was no significant difference in the proportion of individuals with composite ischaemia, major bleeding, or net clinical outcomes at 30 days between those who received bivalirudin plus glycoprotein IIb/IIIa inhibitors and those who received heparin plus glycoprotein IIb/IIIa inhibitors (composite ischaemia: 243 [9%] patients vs 210 [8%] patients, p=0.16; major bleeding: 196 [8%] patients vs 174 [7%] patients, p=0.32; net clinical outcomes: 389 [15%] patients vs 341 [13%] patients, p=0.1). Rates of composite ischaemia were much the same in those who received bivalirudin alone and those who received heparin plus glycoprotein IIb/IIIa inhibitors (230 [9%] patients vs 210 [8%] patients, p=0.45); however, there were significantly fewer individuals who experienced major bleeding among those who received bivalirudin alone than among those who received heparin plus glycoprotein IIb/IIIa inhibitors (92 [4%] patients vs 174 [7%] patients, p<0.0001, relative risk 0.52, 95% CI 0.40-0.66), resulting in a trend towards better 30-day net clinical outcomes (303 [12%] patients vs 341 [13%] patients, p=0.057; 0.87, 0.75-1.00). INTERPRETATION: Substitution of unfractionated heparin or enoxaparin with bivalirudin results in comparable clinical outcomes in patients with moderate and high-risk acute coronary syndromes treated with glycoprotein IIb/IIIa inhibitors in whom percutaneous coronary intervention is done. Anticoagulation with bivalirudin alone suppresses adverse ischaemic events to a similar extent as does heparin plus glycoprotein IIb/IIIa inhibitors, while significantly lowering the risk of major haemorrhagic complications.


Assuntos
Angioplastia Coronária com Balão , Anticoagulantes/uso terapêutico , Isquemia Miocárdica/terapia , Fragmentos de Peptídeos/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada/métodos , Quimioterapia Combinada , Enoxaparina/uso terapêutico , Feminino , Heparina/uso terapêutico , Hirudinas , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico , Inibidores da Agregação Plaquetária/uso terapêutico , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento
18.
Cancer Causes Control ; 19(10): 1305-18, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18704721

RESUMO

OBJECTIVE: To test whether reported associations between race/ethnicity and breast cancer estrogen receptor (ER) status are inflated due to missing ER data, lack of socioeconomic data, and use of the odds ratio (OR) rather than the prevalence ratio (PR). METHODS: We geocoded and added census tract socioeconomic data to all cases of primary invasive breast cancer (n = 42,420) among women diagnosed between 1998 and 2002 in two California cancer registries (San Francisco Bay Area; Los Angeles County) and analyzed the data using log binomial regression. RESULTS: Adjusting for socioeconomic position and tumor characteristics, in models using the imputed data, reduced the PR for the black versus white excess risk of being ER--from 1.76 (95% CI: 1.66, 1.86; adjusted for age and catchment area) to 1.47 (95% CI: 1.38, 1.56). The latter parameter estimate was 16% greater (i.e., 1.56) in models excluding women with missing ER data, and was 43% greater when estimated using the OR (i.e., 1.82). CONCLUSION(S): Studies on race/ethnicity and ER status that fail to account for missing data and socioeconomic data and report the OR are likely to yield inflated estimates of racial/ethnic disparities in ER status.


Assuntos
Neoplasias da Mama/etnologia , Neoplasias da Mama/epidemiologia , Censos , Grupos Raciais/etnologia , Receptores de Estrogênio/metabolismo , Negro ou Afro-Americano/etnologia , Povo Asiático/etnologia , Neoplasias da Mama/diagnóstico , California/epidemiologia , California/etnologia , Área Programática de Saúde , Feminino , Hispânico ou Latino/etnologia , Humanos , Incidência , Havaiano Nativo ou Outro Ilhéu do Pacífico/etnologia , Invasividade Neoplásica , Razão de Chances , Pobreza , Prevalência , Sistema de Registros/estatística & dados numéricos , Análise de Regressão , Fatores Socioeconômicos , População Branca/etnologia
19.
J Biopharm Stat ; 18(6): 1184-96, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18991116

RESUMO

There is considerable interest in methods that use accumulated data to modify trial sample size. However, sample size re-estimation in group sequential designs has been controversial. We describe a method for sample size re-estimation at the penultimate stage of a group sequential design that achieves specified power against an alternative hypothesis corresponding to the current point estimate of the treatment effect.


Assuntos
Ensaios Clínicos como Assunto/estatística & dados numéricos , Interpretação Estatística de Dados , Modelos Estatísticos , Tamanho da Amostra , Simulação por Computador , Humanos , Cadeias de Markov , Fatores de Tempo , Resultado do Tratamento
20.
J Gen Intern Med ; 22(1): 92-7, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17351846

RESUMO

BACKGROUND: Alcohol misuse is a growing public health concern for older adults, particularly among primary care patients. OBJECTIVES: To determine alcohol consumption patterns and the characteristics associated with at-risk drinking in a large sample of elderly primary care patients. DESIGN: Cross-sectional analysis of multisite screening data from 6 VA Medical Centers, 2 hospital-based health care networks, and 3 Community Health Centers. PARTICIPANTS: Patients, 43,606, aged 65 to 103 years, with scheduled primary care appointments were approached for screening; 27,714 (63.6%) consented to be screened. The final sample of persons with completed screens comprised 24,863 patients. MEASUREMENTS: Quantity and frequency of alcohol use, demographics, social support measures, and measures of depression/anxiety. RESULTS: Of the 24,863 older adults screened, 70.0% reported no consumption of alcohol in the past year, 21.5% were moderate drinkers (1-7 drinks/week), 4.1% were at-risk drinkers (8-14 drinks/week), and 4.5% were heavy (>14 drinks/week) or binge drinkers. Heavy drinking showed significant positive association with depressive/anxiety symptoms [Odds ratio (OR) (95% CI): 1.79 (1.30, 2.45)] and less social support [OR (95% CI): 2.01 (1.14, 2.56)]. Heavy drinking combined with binging was similarly positively associated with depressive/anxiety symptoms [OR (95%): 1.70 (1.33, 2.17)] and perceived poor health [OR (95% CI): 1.27 (1.03, 1.57)], while at-risk drinking was not associated with any of these variables. CONCLUSIONS: The majority of participants were nondrinkers; among alcohol users, at-risk drinkers did not differ significantly from moderate drinkers in their characteristics or for the 3 health parameters evaluated. In contrast, heavy drinking was associated with depression and anxiety and less social support, and heavy drinking combined with binge drinking was associated with depressive/anxiety symptoms and perceived poor health.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas/psicologia , Ansiedade/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Feminino , Nível de Saúde , Humanos , Masculino , Atenção Primária à Saúde , Grupos Raciais/estatística & dados numéricos , Distribuição por Sexo , Fatores Sexuais , Apoio Social , Estados Unidos/epidemiologia
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