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1.
Animal ; 18(3): 101100, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38452419

RESUMO

The need to integrate more clearly societal expectations on livestock farming has led the authors of this article to consider that livestock farming systems must be redesigned to position health and welfare at the heart of their objectives. This article proposes a vision of the advances in knowledge required at different scales to contribute to this transformation. After defining health and welfare of animals, the article emphasises the need to consider health in a broader perspective, to deepen the question of positive emotional experiences regarding welfare, and raises the question of how to assess these two elements on farms. The positive interactions between health and welfare are presented. Some possible tensions between them are also discussed, in particular when improving welfare by providing a more stimulating and richer environment such as access to outdoor increases the risk of infectious diseases. Jointly improving health and welfare of animals poses a number of questions at various scales, from the animal level to the production chain. At the animal level, the authors highlight the need to explore: the long-term links between better welfare and physiological balance, the role of microbiota, the psycho-neuro-endocrine mechanisms linking positive mental state and health, and the trade-off between the physiological functions of production, reproduction and immunity. At the farm level, in addition to studying the relationships at the group level between welfare, health and production, the paper supports the idea of co-constructing innovative systems with livestock farmers, as well as analysing the cost, acceptability and impact of improved systems on their working conditions and well-being. At the production chain or territory levels, various questions are raised. These include studying the best strategies to improve animal health and welfare while preserving economic viability, the labelling of products and the consumers' willingness to pay, the consequences of heterogeneity in animal traits on the processing of animal products, and the spatial distribution of livestock farming and the organisation of the production and value chain. At the level of the citizen and consumer, one of the challenges is to better inter-relate sanitary and health perspectives on the one hand, and welfare concerns on the other hand. There is also a need to improve citizens' knowledge on livestock farming, and to develop more intense and constructive exchanges between livestock farmers, the livestock industry and citizens. These difficult issues plead for interdisciplinary and transdisciplinary research involving various scientific disciplines and the different stakeholders, including public policy makers through participatory research.


Assuntos
Criação de Animais Domésticos , Gado , Animais , Humanos , Fazendas , Bem-Estar do Animal , Fazendeiros
2.
Int J Qual Health Care ; 34(4)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36299250

RESUMO

BACKGROUND: A dedicated operating team is defined as a surgical team consisting of the same group of people working together over time, optimally attuned in both technical and/or communicative aspects. This can be achieved through technical and/or communicative training in a team setting. A dedicated surgical team may contribute to the optimization of healthcare quality and patient safety within the perioperative period. METHOD: A systematic review was conducted to evaluate the effects of a dedicated surgical team on clinical and performance outcomes. MEDLINE and Embase were searched on 23 June 2022. Both randomized controlled trials (RCTs) and non-randomized studies (NRSs) were included. Primary outcomes were mortality, complications and readmissions. Secondary outcomes were costs and performance measures. RESULTS: Fourteen studies were included (RCTs n = 1; NRSs n = 13). Implementation of dedicated operating teams was associated with improvements in mortality, turnover time, teamwork, communication and costs. No significant differences were observed in readmission rates and length of hospital stay. Results regarding duration, glitch counts and complications of surgery were inconclusive. Limitations include study conduct and heterogeneity between studies. CONCLUSIONS: The institution of surgical teams who followed communicative and/or technical training appeared to have beneficial effects on several clinical outcome measures. Dedicated teams provide a feasible way of improving healthcare quality and patient safety. A dose-response effect of team training was reported, but also a relapse rate, suggesting that repetitive training is of major concern to high-quality patient care. Further studies are needed to confirm these findings, due to limited level of evidence in current literature. PROSPERO REGISTRATION NUMBER: CRD42020145288.


Assuntos
Comunicação , Equipe de Assistência ao Paciente , Humanos , Tempo de Internação , Qualidade da Assistência à Saúde , Segurança do Paciente
3.
PLoS One ; 17(7): e0270396, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35862384

RESUMO

BACKGROUND: Malnutrition is often present in vascular surgery patient during hospital admission. The present evidence of the consequence malnutrition has on morbidity and mortality is limited. AIM: The purpose of this study was to determine the effect of nutritional status on out-of-hospital mortality in vascular surgery patients. METHODS: An observational cohort study was performed, studying non-cardiac vascular surgery patients surviving hospital admission 18 years or older treated in Boston, Massachusetts, USA. The exposure of interest was nutritional status categorized as well nourished, at-risk for malnutrition, nonspecific malnutrition or protein-energy malnutrition. The all cause 90-day mortality following hospital discharge was the primary outcome. Adjusted odds ratios were estimated by multivariable logistic regression models. RESULTS: This cohort included 4432 patients comprised of 48% women and a mean age 61.7 years. After evaluation by a registered dietitian, 3819 patients were determined to be well nourished, 215 patients were at-risk for malnutrition, 351 had non-specific malnutrition and 47 patients had protein-energy malnutrition. After adjustment for age, sex, ethnicity, medical versus surgical Diagnosis Related Group type, Deyo-Charlson index, length of stay, and vascular Current Procedural Terminology code category, the 90-day post-discharge mortality odds ratio for patients with non-specific malnutrition OR 1.96 (95%CI 1.21, 3.17) and for protein-energy malnutrition OR 3.58 (95%CI 1.59, 8.06), all relative to patients without malnutrition. DISCUSSION: Nutritional status is a strong predictor of out-of-hospital mortality. This suggests that patient with vascular disease suffering from malnutrition could benefit from more intensified In-hospital and out-of-hospital dietary guidance and interventions.


Assuntos
Desnutrição , Desnutrição Proteico-Calórica , Assistência ao Convalescente , Estado Terminal , Feminino , Mortalidade Hospitalar , Humanos , Tempo de Internação , Masculino , Desnutrição/diagnóstico , Pessoa de Meia-Idade , Avaliação Nutricional , Estado Nutricional , Alta do Paciente , Fatores de Risco , Procedimentos Cirúrgicos Vasculares
4.
J Otol ; 16(4): 237-241, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34548870

RESUMO

BACKGROUND: Acute acoustic trauma (AAT) is an acute hearing impairment caused by intense noise-impact. The current management strategy for AAT with substantial hearing loss in the Dutch military is the combination therapy with corticosteroids and hyperbaric oxygen therapy (HBOT). In a previous study, early initiation of the combination therapy was associated with better outcomes. Therefore, we performed a new analysis to assess the difference in hearing outcome between patients in whom combination therapy was started within two days, versus after more than two days. METHODS: A retrospective analysis was performed on military patients diagnosed with AAT with substantial hearing loss who presented between February 2018 and March 2020. Absolute and relative hearing improvement between first and last audiograms were calculated for all affected frequencies (defined as loss of ≥20 dB on initial audiogram). We also determined the amount of patients who recovered to the level of Dutch military requirement, and performed speech discrimination tests. RESULTS: In this analysis, 30 male patients (49 ears) with AAT were included. The median age was 24.5 years (IQR 23-29). The median time to initiation of therapy with corticosteroids and HBOT were one and two days, respectively. HBOT was started within two days in 31 ears, and after more than two days in 18 ears. The mean absolute and relative hearing gains were 18.8 dB (SD 14.6) and 46.8% (SD 31.3) on all affected frequencies. The 100% discrimination/speech perception level improved from 64.0 dB to 51.7 dB (gain 12.3 dB ± 14.1). There was significantly more improvement in absolute and relative hearing improvement when HBOT was started in ≤2 days, compared to >2 days. CONCLUSION: Our analysis shows results in favor of early initiation (≤2 days) of the combination treatment of HBOT and corticosteroids in patients with AAT.

6.
Nutr Metab Cardiovasc Dis ; 29(8): 847-855, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31248714

RESUMO

BACKGROUND AND AIMS: Eosinopenia is a marker for acute inflammation. We hypothesized that eosinopenia at Intensive Care Unit (ICU) admission in vascular surgery patients who receive critical care, would be associated with increased mortality following hospital discharge. METHODS AND RESULTS: We performed a two-center observational cohort study of critically ill, non-cardiac adult vascular surgery patients who received treatment in Boston between 1997 and 2012 and survived hospital admission. The consecutive sample included 5083 patients (male 57%, white 82%, mean age [SD] 61.6 [17.4] years). The exposure was Absolute eosinophil count measured within 24 h of admission to the ICU and categorized as ≤10 cells/µL, 11-50 cells/µL, 51-100 cells/µL, 101-350 cells/µL (normal range), and >350 cells/µL. The primary outcome was all-cause mortality within 90 days of hospital discharge. The secondary outcome was discharge to home following hospitalization. 90-day post-discharge mortality was 6.7%, and 12.9% of patients were readmitted within 30 days. After multivariable adjustment, patients with eosinopenia (≤10 cells/µL) have a 90-day post-discharge mortality OR of 1.97 (95%CI 1.42, 2.73; P < 0.001) relative to patients with an absolute eosinophil count of 101-350 cells/µL. Further, after multivariable adjustment, patients with eosinopenia (≤10 cells/µL) have a 25% lower odds of discharge to home compared to patients with an absolute eosinophil count of 101-350 cells/µL [OR = 0.71 (CI 95% 0.59-0.85); P < 0.001]. CONCLUSION: Eosinopenia at ICU admission is a robust predictor of increased mortality and lower likelihood of discharge to home in vascular surgery patients treated with critical care who survive hospitalization.


Assuntos
Eosinófilos , Doenças Vasculares/cirurgia , Procedimentos Cirúrgicos Vasculares , Idoso , Idoso de 80 Anos ou mais , Boston , Estado Terminal , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Alta do Paciente , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Doenças Vasculares/sangue , Doenças Vasculares/diagnóstico , Doenças Vasculares/mortalidade , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Procedimentos Cirúrgicos Vasculares/mortalidade
8.
Eur J Vasc Endovasc Surg ; 53(2): 168-174, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27916478

RESUMO

OBJECTIVE: The decision whether or not to proceed with surgical intervention of a patient with a ruptured abdominal aortic aneurysm (rAAA) is very difficult in daily practice. The primary objective of the present study was to develop and to externally validate a new prediction model: the Dutch Aneurysm Score (DAS). METHODS: With a prospective cohort of 10 hospitals (n = 508) the DAS was developed using a multivariate logistic regression model. Two retrospective cohorts with rAAA patients from two hospitals (n = 373) were used for external validation. The primary outcome was the combined 30 day and in-hospital death rate. Discrimination (AUC), calibration plots, and the ability to identify high risk patients were compared with the more commonly used Glasgow Aneurysm Score (GAS). RESULTS: After multivariate logistic regression, four pre-operative variables were identified: age, lowest in hospital systolic blood pressure, cardiopulmonary resuscitation, and haemoglobin level. The area under the receiver operating curve (AUC) for the DAS was 0.77 (95% CI 0.72-0.82) compared with the GAS with an AUC of 0.72 (95% CI 0.67-0.77). The DAS showed a death rate in patients with a predicted death rate ≥80% of 83%. CONCLUSIONS: The present study shows that the DAS has a higher discriminative performance (AUC) compared with the GAS. All clinical variables used for the DAS are easy to obtain. Identification of low risk patients with the DAS can potentially reduce turndown rates. The DAS can reliably be used by clinicians to make a more informed decision in dialogue with the patient and their family whether or not to proceed with surgical intervention.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/cirurgia , Técnicas de Apoio para a Decisão , Procedimentos Cirúrgicos Vasculares/mortalidade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/diagnóstico , Aneurisma da Aorta Abdominal/mortalidade , Ruptura Aórtica/diagnóstico , Ruptura Aórtica/mortalidade , Área Sob a Curva , Biomarcadores/sangue , Pressão Sanguínea , Reanimação Cardiopulmonar/mortalidade , Feminino , Escala de Coma de Glasgow , Hemoglobinas/metabolismo , Mortalidade Hospitalar , Humanos , Modelos Logísticos , Masculino , Análise Multivariada , Países Baixos , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos
9.
Tijdschr Psychiatr ; 58(6): 471-5, 2016.
Artigo em Holandês | MEDLINE | ID: mdl-27320511

RESUMO

BACKGROUND: The reduction of coercive measures in psychiatry, particularly of seclusion, is considered to be a matter of some urgency. When policy changes with regard to coercive measures are being considered, the wishes and preferences of patients should be taken into account. Up till now, however, there have not been any studies that have examined how adolescent inpatients feel about coercive measures. AIM: To examine the way adolescent inpatients feel about seclusion and other forms of coercive measures. METHOD: Adolescent inpatients in a Dutch centre for orthopsychiatry (n = 34) were asked about their experiences with and their thoughts on coercive measures in general and on seclusion in particular. RESULTS: Thirty-two respondents took part. More than half of the 18 adolescents who had had prior experiences of coercive measures preferred seclusion to involuntary medication. CONCLUSION: Policy-makers who want to reduce coercive measures in psychiatry should not focus primarily on the reduction of seclusion. Patient preferences, which vary depending on the nature of the patient population, need to be considered carefully and taken into account.


Assuntos
Psiquiatria do Adolescente/métodos , Coerção , Pacientes Internados/psicologia , Isolamento Social/psicologia , Adolescente , Feminino , Humanos , Masculino , Países Baixos , Satisfação do Paciente , Guias de Prática Clínica como Assunto
10.
Animal ; 10(10): 1594-601, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27095244

RESUMO

Exposure of laying hens to chronic heat stress results in loss of egg production. It should be possible to improve hen resilience to chronic heat stress by genetic selection but measuring their sensitivity through internal temperature is time consuming and is not very precise. In this study we used infrared thermography to measure the hen's capacity to dissipate heat, in a commercial line of laying hens subjected to cycles of neutral (N, 19.6°C) or high (H, 28.4°C) ambient temperatures. Mean body temperatures (BT) were estimated from 9355 infrared images of wing, comb and shank taken from 1200 hens. Genetic parameters were estimated separately for N and H temperatures. Correlations between BT and plumage condition were also investigated. Wing temperature had low heritability (0.00 to 0.09), consistent with the fact that wing temperature mainly reflects the environmental temperature and is not a zone of heat dissipation. The heritability of comb temperature was higher, from 0.15 to 0.19 in N and H conditions, respectively. Finally, the shank temperature provided the highest heritability estimates, with values of 0.20 to 0.22 in H and N conditions, respectively. Taken together, these results show that heat dissipation is partly under genetic control. Interestingly, the genetic correlation between plumage condition and shank and comb temperatures indicated that birds with poor condition plumage also had the possibility to dissipate heat through featherless areas. Genetic correlations of temperature measurements with egg quality showed that temperatures were correlated with egg width and weight, yolk brightness and yellowness and Haugh units only under H conditions. In contrast, shell colour was correlated with leg temperature only at thermo-neutrality.


Assuntos
Temperatura Corporal/genética , Galinhas/genética , Ovos/normas , Plumas/fisiologia , Temperatura Alta , Termografia , Animais , Temperatura Corporal/fisiologia , Regulação da Temperatura Corporal/genética , Regulação da Temperatura Corporal/fisiologia , Feminino , Raios Infravermelhos , Oviposição/fisiologia , Óvulo/citologia , Asas de Animais/fisiologia
11.
Ultrasound Obstet Gynecol ; 48(2): 210-6, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26358663

RESUMO

OBJECTIVES: To investigate whether prenatal Doppler parameters in growth-restricted fetuses are correlated with neonatal circulatory changes. METHODS: In 43 cases of suspected fetal growth restriction (FGR), serial Doppler measurements of umbilical artery (UA) and middle cerebral artery (MCA) pulsatility index (PI) were performed. The last measurement, closest to delivery (< 1 week before birth), was used for analysis. Neonatal circulation was assessed for 2 h/day on Days 1-5, 8 and 15 by near-infrared spectroscopy (NIRS) of the cerebral, renal and splanchnic regions. We calculated fractional tissue oxygen extraction (FTOE) as: (arterial oxygen saturation - NIRS value)/arterial oxygen saturation. The following ratios were calculated: cerebroplacental ratio (CPR; MCA-PI/UA-PI), cerebrorenal ratio (CRR; cerebral/renal FTOE) and cerebrosplanchnic ratio (CSR; cerebral/splanchnic FTOE). Spearman's rank correlation coefficient (ρ) was calculated between prenatal Doppler parameters and neonatal NIRS variables. These analyses were carried out for the entire group, and separately for cases of early FGR (delivered < 34 weeks) and late FGR (≥ 34 weeks). RESULTS: Fetal Doppler parameters correlated with neonatal NIRS variables on Days 1-3: UA-PI correlated with renal FTOE (Day 1: ρ = 0.454, P < 0.01) and CRR (Day 1: ρ = -0.517, P < 0.001). MCA-PI correlated with cerebral FTOE on Day 2 (ρ = 0.469, P < 0.01), approached statistical significance on Day 3 but was not correlated on Day 1. CPR correlated with CRR (Day 1: ρ = 0.474, P < 0.01). Most associations lost their statistical significance when early and late FGR subgroups were considered separately. CONCLUSION: Low MCA-PI and low CPR, indicating brain sparing before birth, are associated with low CRR after birth, indicating relatively greater blood flow to the cerebrum than to the renal region. Based on the results of this study, it could be speculated that if brain sparing is present in the fetal circulation, it persists during the first 3 days after birth. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Retardo do Crescimento Fetal/diagnóstico por imagem , Retardo do Crescimento Fetal/fisiopatologia , Feto/irrigação sanguínea , Fluxometria por Laser-Doppler/métodos , Artéria Cerebral Média/fisiopatologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Artérias Umbilicais/fisiopatologia , Feminino , Humanos , Recém-Nascido , Masculino , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/embriologia , Gravidez , Estudos Prospectivos , Ultrassonografia Pré-Natal/métodos , Artérias Umbilicais/diagnóstico por imagem , Artérias Umbilicais/embriologia
12.
J Anim Sci ; 93(4): 1830-40, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26020204

RESUMO

Coccidiosis, a parasitic disease of the intestinal tract caused by members of the genera Eimeria and Isospora, is one of the most common and costly diseases in chicken. The aims of this study were to assess the effect of the challenge and level of variability of measured parameters in chickens during the challenge with Eimeria maxima. Furthermore, this study aimed to investigate which parameters are the most relevant indicators of the health status. Finally, the study also aimed to estimate accuracy of prediction for traits that cannot be measured on large scale (such as intestinal lesion score and fecal oocyst count) using parameters that can easily be measured on all animals. The study was performed in 2 parts: a pilot challenge on 240 animals followed by a large-scale challenge on 2,024 animals. In both experiments, animals were challenged with 50,000 Eimeria maxima oocysts at 16 d of age. In the pilot challenge, all animals were measured for BW gain, plasma coloration, hematocrit, and rectal temperature and, in addition, a subset of 48 animals was measured for oocyst count and the intestinal lesion score. All animals from the second challenge were measured for BW gain, plasma coloration, and hematocrit whereas a subset of 184 animals was measured for intestinal lesion score, fecal oocyst count, blood parameters, and plasma protein content and composition. Most of the parameters measured were significantly affected by the challenge. Lesion scores for duodenum and jejunum (P < 0.001), oocyst count (P < 0.05), plasma coloration for the optical density values between 450 and 490 nm (P < 0.001), albumin (P < 0.001), α1-globulin (P < 0.01), α2-globulin (P < 0.001), α3-globulin (P < 0.01), and ß2-globulin (P < 0.001) were the most strongly affected parameters and expressed the greatest levels of variation. Plasma protein profiles proved to be a new, reliable parameter for measuring response to Eimeria maxima. Prediction of intestinal lesion score and fecal oocyst count using the other parameters measured was not very precise (R2 < 0.7). The study was successfully performed in real raising conditions on a large scale. Finally, we observed a high variability in response to the challenge, suggesting that broilers' response to Eimeria maxima has a strong genetic determinism, which may be improved by genetic selection.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Eimeria/isolamento & purificação , Fezes/parasitologia , Intestinos/parasitologia , Doenças das Aves Domésticas/parasitologia , Animais , Proteínas Sanguíneas/metabolismo , Temperatura Corporal/fisiologia , Peso Corporal/fisiologia , Galinhas/sangue , Galinhas/fisiologia , Coccidiose/parasitologia , Feminino , Hematócrito , Masculino , Oocistos/parasitologia , Projetos Piloto , Distribuição Aleatória
13.
Soc Sci Med ; 113: 68-76, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24852657

RESUMO

Providing patients with more person-centred care without increasing costs is a key challenge in healthcare. A relevant but often ignored hindrance to delivering person-centred care is that the current segmentation of the population and the associated organization of healthcare supply are based on diseases. A person-centred segmentation, i.e., based on persons' own experienced difficulties in fulfilling needs, is an elementary but often overlooked first step in developing efficient demand-driven care. This paper describes a person-centred segmentation study of elderly, a large and increasing target group confronted with heterogeneous and often interrelated difficulties in their functioning. In twenty-five diverse healthcare and welfare organizations as well as elderly associations in the Netherlands, data were collected on the difficulties in biopsychosocial functioning experienced by 2019 older adults. Data were collected between March 2010 and January 2011 and sampling took place based on their (temporarily) living conditions. Factor Mixture Model was conducted to categorize the respondents into segments with relatively similar experienced difficulties concerning their functioning. First, the analyses show that older adults can be empirically categorized into five meaningful segments: feeling vital; difficulties with psychosocial coping; physical and mobility complaints; difficulties experienced in multiple domains; and feeling extremely frail. The categorization seems robust as it was replicated in two population-based samples in the Netherlands. The segmentation's usefulness is discussed and illustrated through an evaluation of the alignment between a segment's unfulfilled biopsychosocial needs and current healthcare utilization. The set of person-centred segmentation variables provides healthcare providers the option to perform a more comprehensive first triage step than only a disease-based one. The outcomes of this first step could guide a focused and, therefore, more efficient second triage step. On a local or regional level, this person-centred segmentation provides input information to policymakers and care providers for the demand-driven allocation of resources.


Assuntos
Atividades Cotidianas/psicologia , Eficiência Organizacional , Serviços de Saúde para Idosos/organização & administração , Avaliação das Necessidades , Assistência Centrada no Paciente/organização & administração , Idoso , Idoso de 80 Anos ou mais , Pesquisa Empírica , Feminino , Alocação de Recursos para a Atenção à Saúde , Reforma dos Serviços de Saúde , Serviços de Saúde para Idosos/estatística & dados numéricos , Humanos , Masculino , Países Baixos
15.
Scand Stat Theory Appl ; 41(1): 104-140, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30100663

RESUMO

This article is devoted to the construction and asymptotic study of adaptive group sequential covariate-adjusted randomized clinical trials analyzed through the prism of the semipara-metric methodology of targeted maximum likelihood estimation (TMLE). We show how to build, as the data accrue group-sequentially, a sampling design which targets a user-supplied optimal design. We also show how to carry out a sound TMLE statistical inference based on such an adaptive sampling scheme (therefore extending some results known in the i.i.d setting only so far), and how group-sequential testing applies on top of it. The procedure is robust (i.e., consistent even if the working model is misspecified). A simulation study confirms the theoretical results, and validates the conjecture that the procedure may also be efficient.

16.
J Nutr Health Aging ; 17(8): 666-73, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24097020

RESUMO

OBJECTIVE: This study quantifies the effects of leisure-time physical activity (LTPA) on walking speed independently of body composition in an elderly cohort, and in those elderly with metabolic derangements due to age, diabetes, and cardiovascular disease (CVD). METHODS: 1655 community-dwelling women and men >55 years were measured for body composition (lean mass : fat mass ratio, LNFAT) , based on estimated bioelectric impedance by using population-specific prediction equations derived from dual-energy x-ray absorptiometry. In addition to LNFAT, LTPA, diabetes, CVD, walking speed, and other covariates were measured biannually over an 8-year period. LTPA was categorized as <22.5 Mets/week, ≥ 22.5 Mets/week, based on public-health recommended guidelines, and LNFAT was dichotomized based on its sex-specific median. Direct effects of high vs. low LTPA on walking speed were estimated for fixed levels of LNFAT, which represented an intermediary variable in the analysis. Stratified estimates of effects were obtained using subject status (e.g., age≥75 years, diabetes, CVD) at each visit. RESULTS: Walking speed was significantly greater (0.74, 0.75 m/s in women and men, respectively) if subjects experienced LTPA ≥22.5 Mets/week and > median LNFAT, compared with <22.5 Mets/week and ≤ median LNFAT (0.68, 0.69 m/s). While direct effects of LTPA contributed to higher walking speed, none were significant in the overall, nor the stratified groups of subjects, of either sex. CONCLUSIONS: Walking speed increases with greater LTPA and LNFAT in the elderly, but there was no evidence to indicate that walking speed increases from LTPA independently of body composition and the metabolic processes it represents.


Assuntos
Exercício Físico/fisiologia , Atividades de Lazer , Esforço Físico/fisiologia , Aptidão Física/fisiologia , Idoso , Envelhecimento/metabolismo , Composição Corporal , Doenças Cardiovasculares/metabolismo , Estudos de Coortes , Diabetes Mellitus/metabolismo , Feminino , Avaliação Geriátrica , Humanos , Masculino , Equivalente Metabólico , Pessoa de Meia-Idade , Caminhada
17.
Br J Surg ; 100(11): 1405-13, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24037558

RESUMO

BACKGROUND: A substantial proportion of patients with a ruptured abdominal aortic aneurysm (rAAA) die outside hospital. The objective of this study was to estimate the total mortality, including prehospital deaths, of patients with rAAA. METHODS: This was a systematic review and meta-analysis following the MOOSE guidelines. The Embase, MEDLINE and Cochrane Library databases were searched. All population-based studies reporting both prehospital and in-hospital mortality in patients with rAAA were included. Studies were assessed for methodological quality and heterogeneity, and pooled estimates of mortality from rAAA were calculated using a random-effects model. RESULTS: From a total of 3667 studies, 24 retrospective cohort studies, published between 1977 and 2012, met the inclusion criteria. The quality of included studies varied, in particular the method of determining prehospital deaths from rAAA. The estimated pooled total mortality rate was 81 (95 per cent confidence interval 78 to 83) per cent. A decline in mortality was observed over time (P = 0·002); the pooled estimate of total mortality in high-quality studies before 1990 was 86 (83 to 89) per cent, compared with 74 (72 to 77) per cent since 1990. Some 32 (27 to 37) per cent of patients with rAAA died before reaching hospital. The in-hospital non-intervention rate was 40 (33 to 47) per cent, which also declined over the years. CONCLUSION: The pooled estimate of total mortality from rAAA is very high, although it has declined over the years. Most patients die outside hospital, and there is no surgical intervention in a considerable number of those who survive to reach hospital.


Assuntos
Aneurisma da Aorta Abdominal/mortalidade , Ruptura Aórtica/mortalidade , Idoso , Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/cirurgia , Serviços Médicos de Emergência/estatística & dados numéricos , Feminino , Humanos , Masculino , Assistência Perioperatória/mortalidade , Estudos Retrospectivos , Taxa de Sobrevida
19.
Biometrika ; 98(4): 845-860, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23049131

RESUMO

It is a challenge to evaluate experimental treatments where it is suspected that the treatment effect may only be strong for certain subpopulations, such as those having a high initial severity of disease, or those having a particular gene variant. Standard randomized controlled trials can have low power in such situations. They also are not optimized to distinguish which subpopulations benefit from a treatment. With the goal of overcoming these limitations, we consider randomized trial designs in which the criteria for patient enrollment may be changed, in a preplanned manner, based on interim analyses. Since such designs allow data-dependent changes to the population enrolled, care must be taken to ensure strong control of the familywise Type I error rate. Our main contribution is a general method for constructing randomized trial designs that allow changes to the population enrolled based on interim data using a prespecified decision rule, for which the asymptotic, familywise Type I error rate is strongly controlled at a specified level α. As a demonstration of our method, we prove new, sharp results for a simple, two-stage enrichment design. We then compare this design to fixed designs, focusing on each design's ability to determine the overall and subpopulation-specific treatment effects.

20.
Stat Med ; 28(1): 39-64, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-18985634

RESUMO

Covariate adjustment using linear models for continuous outcomes in randomized trials has been shown to increase efficiency and power over the unadjusted method in estimating the marginal effect of treatment. However, for binary outcomes, investigators generally rely on the unadjusted estimate as the literature indicates that covariate-adjusted estimates based on the logistic regression models are less efficient. The crucial step that has been missing when adjusting for covariates is that one must integrate/average the adjusted estimate over those covariates in order to obtain the marginal effect. We apply the method of targeted maximum likelihood estimation (tMLE) to obtain estimators for the marginal effect using covariate adjustment for binary outcomes. We show that the covariate adjustment in randomized trials using the logistic regression models can be mapped, by averaging over the covariate(s), to obtain a fully robust and efficient estimator of the marginal effect, which equals a targeted maximum likelihood estimator. This tMLE is obtained by simply adding a clever covariate to a fixed initial regression. We present simulation studies that demonstrate that this tMLE increases efficiency and power over the unadjusted method, particularly for smaller sample sizes, even when the regression model is mis-specified.


Assuntos
Funções Verossimilhança , Modelos Lineares , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Humanos , Resultado do Tratamento
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