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1.
Ecol Appl ; 32(4): e2545, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35084804

RESUMO

Medicinal plants contribute substantially to the well-being of people in large parts of the world, providing traditional medicine and supporting livelihoods from trading plant parts, which is especially significant for women in low-income communities. However, the availability of wild medicinal plants is increasingly threatened; for example, the Natal Lily (Clivia miniata), which is one of the most widely traded plants in informal medicine markets in South Africa, lost over 40% of individuals over the last 90 years. Understanding the species' response to individual and multiple pressures is essential for prioritizing and planning conservation actions. To gain this understanding, we simulated the future range and abundance of C. miniata by coupling Species Distribution Models with a metapopulation model (RAMAS-GIS). We contrasted scenarios of climate change (RCP2.6 vs. RCP8.5), land cover change (intensification vs. expansion), and harvesting (only juveniles vs. all life-stages). All our scenarios pointed to continuing declines in suitable habitat and abundance by the 2050s. When acting independently, climate change, land cover change, and harvesting each reduced the projected abundance substantially, with land cover change causing the most pronounced declines. Harvesting individuals from all life stages affected the projected metapopulation size more negatively than extracting only juveniles. When the three pressures acted together, declines of suitable habitat and abundance accelerated but uncertainties were too large to identify whether pressures acted synergistically, additively, or antagonistically. Our results suggest that conservation should prioritize the protection of suitable habitat and ensure sustainable harvesting to support a viable metapopulation under realistic levels of climate change. Inadequate management of C. miniata populations in the wild will likely have negative consequences for the well-being of people relying on this ecosystem service, and we expect there may be comparable consequences relating to other medicinal plants in different parts of the world.


Assuntos
Amaryllidaceae/fisiologia , Mudança Climática , Plantas Medicinais/fisiologia , Amaryllidaceae/crescimento & desenvolvimento , Conservação dos Recursos Naturais , Ecossistema , Feminino , Humanos , Medicina Tradicional/métodos , Plantas Medicinais/crescimento & desenvolvimento , Pobreza , África do Sul
2.
Eur J Public Health ; 30(5): 922-928, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31576400

RESUMO

BACKGROUND: In this review article, we detail a small but growing literature in the field of health geography that uses longitudinal data to determine a life course component to the neighbourhood effects thesis. For too long, there has been reliance on cross-sectional data to test the hypothesis that where you live has an effect on your health and well-being over and above your individual circumstances. METHODS: We identified 53 articles that demonstrate how neighbourhood deprivation measured at least 15 years prior affects health and well-being later in life using the databases Scopus and Web of Science. RESULTS: We find a bias towards US studies, the most common being the Panel Study of Income Dynamics. Definition of neighbourhood and operationalization of neighbourhood deprivation across most of the included articles relied on data availability rather than a priori hypothesis. CONCLUSIONS: To further progress neighbourhood effects research, we suggest that more data linkage to longitudinal datasets is required beyond the narrow list identified in this review. The limited literature published to date suggests an accumulation of exposure to neighbourhood deprivation over the life course is damaging to later life health, which indicates improving neighbourhoods as early in life as possible would have the greatest public health improvement.


Assuntos
Características de Residência , Estudos Transversais , Humanos , Fatores Socioeconômicos
3.
Lancet ; 383(9925): 1305-1312, 2014 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-24461715

RESUMO

BACKGROUND: International research for acute myocardial infarction lacks comparisons of whole health systems. We assessed time trends for care and outcomes in Sweden and the UK. METHODS: We used data from national registries on consecutive patients registered between 2004 and 2010 in all hospitals providing care for acute coronary syndrome in Sweden and the UK. The primary outcome was all-cause mortality 30 days after admission. We compared effectiveness of treatment by indirect casemix standardisation. This study is registered with ClinicalTrials.gov, number NCT01359033. FINDINGS: We assessed data for 119,786 patients in Sweden and 391,077 in the UK. 30-day mortality was 7·6% (95% CI 7·4-7·7) in Sweden and 10·5% (10·4-10·6) in the UK. Mortality was higher in the UK in clinically relevant subgroups defined by troponin concentration, ST-segment elevation, age, sex, heart rate, systolic blood pressure, diabetes mellitus status, and smoking status. In Sweden, compared with the UK, there was earlier and more extensive uptake of primary percutaneous coronary intervention (59% vs 22%) and more frequent use of ß blockers at discharge (89% vs 78%). After casemix standardisation the 30-day mortality ratio for UK versus Sweden was 1·37 (95% CI 1·30-1·45), which corresponds to 11,263 (95% CI 9620-12,827) excess deaths, but did decline over time (from 1·47, 95% CI 1·38-1·58 in 2004 to 1·20, 1·12-1·29 in 2010; p=0·01). INTERPRETATION: We found clinically important differences between countries in acute myocardial infarction care and outcomes. International comparisons research might help to improve health systems and prevent deaths. FUNDING: Seventh Framework Programme for Research, National Institute for Health Research, Wellcome Trust (UK), Swedish Association of Local Authorities and Regions, Swedish Heart-Lung Foundation.


Assuntos
Infarto do Miocárdio/mortalidade , Idoso , Feminino , Humanos , Masculino , Infarto do Miocárdio/terapia , Sistema de Registros , Fatores de Risco , Análise de Sobrevida , Suécia/epidemiologia , Reino Unido/epidemiologia
4.
Eur Heart J ; 35(13): 844-52, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24353280

RESUMO

AIMS: The population with stable coronary artery disease (SCAD) is growing but validated models to guide their clinical management are lacking. We developed and validated prognostic models for all-cause mortality and non-fatal myocardial infarction (MI) or coronary death in SCAD. METHODS AND RESULTS: Models were developed in a linked electronic health records cohort of 102 023 SCAD patients from the CALIBER programme, with mean follow-up of 4.4 (SD 2.8) years during which 20 817 deaths and 8856 coronary outcomes were observed. The Kaplan-Meier 5-year risk was 20.6% (95% CI, 20.3, 20.9) for mortality and 9.7% (95% CI, 9.4, 9.9) for non-fatal MI or coronary death. The predictors in the models were age, sex, CAD diagnosis, deprivation, smoking, hypertension, diabetes, lipids, heart failure, peripheral arterial disease, atrial fibrillation, stroke, chronic kidney disease, chronic pulmonary disease, liver disease, cancer, depression, anxiety, heart rate, creatinine, white cell count, and haemoglobin. The models had good calibration and discrimination in internal (external) validation with C-index 0.811 (0.735) for all-cause mortality and 0.778 (0.718) for non-fatal MI or coronary death. Using these models to identify patients at high risk (defined by guidelines as 3% annual mortality) and support a management decision associated with hazard ratio 0.8 could save an additional 13-16 life years or 15-18 coronary event-free years per 1000 patients screened, compared with models with just age, sex, and deprivation. CONCLUSION: These validated prognostic models could be used in clinical practice to support risk stratification as recommended in clinical guidelines.


Assuntos
Doença da Artéria Coronariana/mortalidade , Idoso , Morte Súbita Cardíaca/epidemiologia , Registros Eletrônicos de Saúde , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Infarto do Miocárdio/mortalidade , Prognóstico , Medição de Risco
5.
Am J Epidemiol ; 179(6): 764-74, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24589914

RESUMO

Multivariate imputation by chained equations (MICE) is commonly used for imputing missing data in epidemiologic research. The "true" imputation model may contain nonlinearities which are not included in default imputation models. Random forest imputation is a machine learning technique which can accommodate nonlinearities and interactions and does not require a particular regression model to be specified. We compared parametric MICE with a random forest-based MICE algorithm in 2 simulation studies. The first study used 1,000 random samples of 2,000 persons drawn from the 10,128 stable angina patients in the CALIBER database (Cardiovascular Disease Research using Linked Bespoke Studies and Electronic Records; 2001-2010) with complete data on all covariates. Variables were artificially made "missing at random," and the bias and efficiency of parameter estimates obtained using different imputation methods were compared. Both MICE methods produced unbiased estimates of (log) hazard ratios, but random forest was more efficient and produced narrower confidence intervals. The second study used simulated data in which the partially observed variable depended on the fully observed variables in a nonlinear way. Parameter estimates were less biased using random forest MICE, and confidence interval coverage was better. This suggests that random forest imputation may be useful for imputing complex epidemiologic data sets in which some patients have missing data.


Assuntos
Inteligência Artificial , Simulação por Computador , Métodos Epidemiológicos , Fatores Etários , Angina Estável/epidemiologia , Viés , Intervalos de Confiança , Comportamentos Relacionados com a Saúde , Nível de Saúde , Humanos , Modelos de Riscos Proporcionais , Distribuição Aleatória , Fatores Sexuais
6.
Afr Health Sci ; 22(4): 168-177, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37092075

RESUMO

Background: Bertolotti syndrome is a differential diagnosis in back pain. We know little about it in Uganda. This study aimed to describe the prevalence, clinical and radiological patterns of Bertolotti syndrome and functional disability associated with it. Methods: We did a descriptive cross-sectional study at the spine outpatients' clinic of Mulago National Referral Hospital. We screened patients with chronic low back pain for lumbosacral transitional vertebrae over four months and classified them according to Castellvi. We collected demographics, clinical symptoms, and functional disability data and summarized it descriptively. Results: Out of 385 patients, we identified 39 with Bertolotti syndrome. The prevalence and the median age were at 10.1% and 49 years respectively, with most patients being females (66.7%) in the age range of (36 to 50) years, the pain started during the age range of 31-40. The commonest and least were type IIA (20.5%) and type IV (10.3%), respectively. Most patients (66.3%) had radicular symptoms, mainly the toe extension nerve root. The average visual analog scale was 6.3. However, most patients suffered from mild- to moderate disability (66.7%). Conclusion: Bertolotti syndrome is common and functionally debilitating. We should consider it in the differential diagnosis of chronic low back pain.


Assuntos
Dor Lombar , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Masculino , Dor Lombar/epidemiologia , Estudos Transversais , Prevalência , Medição da Dor , Uganda/epidemiologia
7.
Wellcome Open Res ; 7: 147, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38504774

RESUMO

Background: A shift toward human diets that include more fruit and vegetables, and less meat is a potential pathway to improve public health and reduce food system-related greenhouse gas emissions. Associated changes in land use could include conversion of grazing land into horticulture, which makes more efficient use of land per unit of dietary energy and frees-up land for other uses. Methods: Here we use Great Britain as a case study to estimate potential impacts on biodiversity from converting grazing land to a mixture of horticulture and natural land covers by fitting species distribution models for over 800 species, including pollinating insects and species of conservation priority. Results: Across several land use scenarios that consider the current ratio of domestic fruit and vegetable production to imports, our statistical models suggest a potential for gains to biodiversity, including a tendency for more species to gain habitable area than to lose habitable area. Moreover, the models suggest that climate change impacts on biodiversity could be mitigated to a degree by land use changes associated with dietary shifts. Conclusions: Our analysis demonstrates that options exist for changing agricultural land uses in a way that can generate win-win-win outcomes for biodiversity, adaptation to climate change and public health.

8.
Radiother Oncol ; 172: 32-41, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35513132

RESUMO

PURPOSE: To compare dose distributions and robustness in treatment plans from eight European centres in preparation for the European randomized phase-III PROTECT-trial investigating the effect of proton therapy (PT) versus photon therapy (XT) for oesophageal cancer. MATERIALS AND METHODS: All centres optimized one PT and one XT nominal plan using delineated 4DCT scans for four patients receiving 50.4 Gy (RBE) in 28 fractions. Target volume receiving 95% of prescribed dose (V95%iCTVtotal) should be >99%. Robustness towards setup, range, and respiration was evaluated. The plans were recalculated on a surveillance 4DCT (sCT) acquired at fraction ten and robustness evaluation was performed to evaluate the effect of respiration and inter-fractional anatomical changes. RESULTS: All PT and XT plans complied with V95%iCTVtotal >99% for the nominal plan and V95%iCTVtotal >97% for all respiratory and robustness scenarios. Lung and heart dose varied considerably between centres for both modalities. The difference in mean lung dose and mean heart dose between each pair of XT and PT plans was in median [range] 4.8 Gy [1.1;7.6] and 8.4 Gy [1.9;24.5], respectively. Patients B and C showed large inter-fractional anatomical changes on sCT. For patient B, the minimum V95%iCTVtotal in the worst-case robustness scenario was 45% and 94% for XT and PT, respectively. For patient C, the minimum V95%iCTVtotal was 57% and 72% for XT and PT, respectively. Patient A and D showed minor inter-fractional changes and the minimum V95%iCTVtotal was >85%. CONCLUSION: Large variability in dose to the lungs and heart was observed for both modalities. Inter-fractional anatomical changes led to larger target dose deterioration for XT than PT plans.


Assuntos
Neoplasias Esofágicas , Terapia com Prótons , Radioterapia de Intensidade Modulada , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/radioterapia , Humanos , Terapia com Prótons/métodos , Prótons , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos
9.
PLoS Med ; 8(5): e1000439, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21655315

RESUMO

BACKGROUND: Low haemoglobin concentration has been associated with adverse prognosis in patients with angina and myocardial infarction (MI), but the strength and shape of the association and the presence of any threshold has not been precisely evaluated. METHODS AND FINDINGS: A retrospective cohort study was carried out using the UK General Practice Research Database. 20,131 people with a new diagnosis of stable angina and no previous acute coronary syndrome, and 14,171 people with first MI who survived for at least 7 days were followed up for a mean of 3.2 years. Using semi-parametric Cox regression and multiple adjustment, there was evidence of threshold haemoglobin values below which mortality increased in a graded continuous fashion. For men with MI, the threshold value was 13.5 g/dl (95% confidence interval [CI] 13.2-13.9); the 29.5% of patients with haemoglobin below this threshold had an associated hazard ratio for mortality of 2.00 (95% CI 1.76-2.29) compared to those with haemoglobin values in the lowest risk range. Women tended to have lower threshold haemoglobin values (e.g, for MI 12.8 g/dl; 95% CI 12.1-13.5) but the shape and strength of association did not differ between the genders, nor between patients with angina and MI. We did a systematic review and meta-analysis that identified ten previously published studies, reporting a total of only 1,127 endpoints, but none evaluated thresholds of risk. CONCLUSIONS: There is an association between low haemoglobin concentration and increased mortality. A large proportion of patients with coronary disease have haemoglobin concentrations below the thresholds of risk defined here. Intervention trials would clarify whether increasing the haemoglobin concentration reduces mortality.


Assuntos
Angina Pectoris/mortalidade , Hemoglobinas/análise , Infarto do Miocárdio/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Angina Pectoris/epidemiologia , Estudos de Coortes , Registros Eletrônicos de Saúde , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Reino Unido/epidemiologia
10.
Artigo em Inglês | MEDLINE | ID: mdl-34639611

RESUMO

There is an overreliance on concurrent neighbourhood deprivation as a determinant of health. Only a small section of the literature focuses on the cumulative exposure of neighbourhood deprivation over the life course. This paper uses data from the 1958 National Child Development Study, a British birth cohort study, linked to 1971-2011 Census data at the neighbourhood level to longitudinally model self-rated health between ages 23 and 55 by Townsend deprivation score between ages 16 and 55. Change in self-rated health is analysed using ordinal multilevel models to test the strength of association with neighbourhood deprivation at age 16, concurrently and cumulatively. The results show that greater neighbourhood deprivation at age 16 predicts worsening self-rated health between ages 33 and 50. The association with concurrent neighbourhood deprivation is shown to be stronger compared with the measurement at age 16 when both are adjusted in the model. The concurrent association with change in self-rated health is explained by cumulative neighbourhood deprivation. These findings suggest that neglecting exposure to neighbourhood deprivation over the life course will underestimate the neighbourhood effect. They also have potential implications for public policy suggesting that neighbourhood socioeconomic equality may bring about better population health.


Assuntos
Características de Residência , Adolescente , Adulto , Criança , Estudos de Coortes , Humanos , Pessoa de Meia-Idade , Análise Multinível , Fatores Socioeconômicos , Adulto Jovem
11.
Artigo em Inglês | MEDLINE | ID: mdl-34444095

RESUMO

Neighborhood effects research is plagued by the inability to circumvent selection effects -the process of people sorting into neighborhoods. Data from two British Birth Cohorts, 1958 (ages 16, 23, 33, 42, 55) and 1970 (ages 16, 24, 34, 42), and structural equation modelling, were used to investigate life course relationships between body mass index (BMI) and area deprivation (addresses at each age linked to the closest census 1971-2011 Townsend score [TOWN], re-calculated to reflect consistent 2011 lower super output area boundaries). Initially, models were examined for: (1) area deprivation only, (2) health selection only and (3) both. In the best-fitting model, all relationships were then tested for effect modification by residential mobility by inclusion of interaction terms. For both cohorts, both BMI and area deprivation strongly tracked across the life course. Health selection, or higher BMI associated with higher area deprivation at the next study wave, was apparent at three intervals: 1958 cohort, BMI at age 23 y and TOWN at age 33 y and BMI at age 33 y and TOWN at age 42 y; 1970 cohort, BMI at age 34 y and TOWN at age 42 y, while paths between area deprivation and BMI at the next interval were seen in both cohorts, over all intervals, except for the association between TOWN at age 23 y and BMI at age 33 y in the 1958 cohort. None of the associations varied by moving status. In conclusion, for BMI, selective migration does not appear to account for associations between area deprivation and BMI across the life course.


Assuntos
Características de Residência , População Branca , Adolescente , Adulto , Índice de Massa Corporal , Estudos de Coortes , Humanos , Adulto Jovem
12.
Am J Prev Cardiol ; 7: 100220, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34611646

RESUMO

OBJECTIVES: Adverse childhood experience is thought to be associated with risk of coronary heart disease, but it is not clear which experiences are cardiotoxic, and whether risk increases with the accumulation of adverse childhood experiences. METHODS: Participants were 5149 adults (72.6% men) in the Whitehall II cohort study. Parental death was recorded at phase 1 (median age in years 44.3), and 13 other adverse childhood experiences at phase 5 (55.3). We applied Cox proportional hazards regression with person-time from phase 5 to examine associations of adverse childhood experiences with incident coronary heart disease. We predicted hazard ratios according to count of the experiences, and examined dose-response effect. We finally estimated reduction of coronary heart disease in a hypothetical scenario, the absence of adverse childhood experiences. RESULTS: Among study participants, 62.9% had at least one adversity, with "financial problems" having the highest prevalence (26.1%). There were 509 first episodes of coronary heart disease during an average 12.9 years follow-up. Among 14 adverse childhood experiences in a multiply adjusted model, "parental unemployment" showed the highest hazard of coronary heart disease incidence (hazard ratio; 95% confidence interval: 1.53; 1.16 to 2.02). No dose-response effect was observed (constant for proportionality in hazard ratio: 1.05, 0.99 to 1.11). Based on the estimates of final model, in the absence of childhood adversities, we estimated a 6.0% reduction in coronary heart disease (0.94; 0.87 to 1.01), but the confidence interval includes one. CONCLUSION: Although individual adverse childhood experiences show some association with coronary heart disease, there is no clear relationship with the number of adverse experiences. Further research is required to quantify effects of multiple and combinations of adverse childhood experiences considering timing, duration, and severity.

13.
Patient ; 14(5): 545-553, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33355918

RESUMO

BACKGROUND: Neoadjuvant chemoradiotherapy for oesophageal cancer significantly improves overall survival but is associated with severe post-operative complications. Proton beam therapy may reduce these toxicities by sparing normal tissues compared with standard radiotherapy. ProtOeus is a proposed randomised phase II study of neoadjuvant chemoradiotherapy in oesophageal cancer that compares proton beam therapy to standard radiotherapy techniques. As proton beam therapy services are often centralised in academic centres in major cities, proton beam therapy trials raise distinct challenges including patient acceptance of travelling for proton beam therapy, coordination of treatments with local centres and ensuring equity of access for patients. METHODS: Focus groups were held early in the trial development process to establish patients' views on the trial proposal. Topics discussed include perception of proton beam therapy, patient acceptability of the trial pathway and design, patient-facing materials, and common clinical scenarios. Focus groups were led by the investigators and facilitated by patient involvement teams from the institutions who are involved in this research. Responses for each topic were analysed, and fed back to the trial's development group. RESULTS: Three focus groups were held in separate locations in the UK (Manchester, Cardiff, Wigan). Proton beam therapy was perceived as superior to standard radiotherapy making the trial attractive. Patients felt strongly that travel costs should be reimbursed to ensure equity of access to proton beam therapy. They were very supportive of a shorter treatment schedule and felt that toxicity reduction was the most important endpoint. DISCUSSION AND CONCLUSIONS: Incorporating patient views early in the trial development process resulted in significant trial design refinements including travel/accommodation provisions, choice of primary endpoint, randomisation ratio and fractionation schedule. Focus groups are a reproducible and efficient method of incorporating the patient and public voice into research.


Assuntos
Neoplasias Esofágicas , Terapia com Prótons , Neoplasias Esofágicas/radioterapia , Humanos
14.
Am J Clin Nutr ; 114(2): 530-539, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-33871601

RESUMO

BACKGROUND: Fruit and vegetable consumption in the United Kingdom is currently well below recommended levels, with a significant associated public health burden. The United Kingdom has committed to reducing its carbon emissions to net zero by 2050, and this transition will require shifts towards plant-based diets. OBJECTIVE: The aim was to quantify the health effects, environmental footprints, and cost associated with 4 different pathways to meeting the United Kingdom's "5-a-day" recommendation for fruit and vegetable consumption. METHODS: Dietary data based on 18,006 food diaries from 4528 individuals participating in the UK National Diet and Nutrition Survey (2012/13-2016/17) constituted the baseline diet. Linear programming was used to model the hypothetical adoption of the 5-a-day (400 g) recommendation, which was assessed according to 4 pathways differing in their prioritization of fruits versus vegetables and UK-produced versus imported varieties. Increases in fruit and vegetable consumption were substituted for consumption of sweet snacks and meat, respectively. Changes in life expectancy were assessed using the IOMLIFET life table model. Greenhouse gas emissions (GHGEs), blue water footprint (WF), and total diet cost were quantified for each 5-a-day diet. RESULTS: Achieving the 5-a-day target in the United Kingdom could increase average life expectancy at birth by 7-8 mo and reduce diet-related GHGEs by 6.1 to 12.2 Mt carbon dioxide equivalents/y; blue WFs would change by -0.14 to +0.07 km3/y. Greater reductions in GHGEs were achieved by prioritizing increased vegetable consumption over fruit, whereas the greatest reduction in WF was obtained by prioritizing vegetable varieties produced in the United Kingdom. All consumption pathways increased diet cost (£0.34-£0.46/d). CONCLUSIONS: Benefits to both population and environmental health could be expected from consumption pathways that meet the United Kingdom's 5-a-day target for fruit and vegetables. Our analysis identifies cross-sectoral trade-offs and opportunities for national policy to promote fruit and vegetable consumption in the United Kingdom.


Assuntos
Inquéritos sobre Dietas , Dieta/normas , Meio Ambiente , Frutas , Gases de Efeito Estufa , Verduras , Alimentos/economia , Humanos , Longevidade , Reino Unido
15.
Radiother Oncol ; 156: 102-112, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33285194

RESUMO

PURPOSE: To define instructions for delineation of target volumes in the neoadjuvant setting in oesophageal cancer. MATERIALS AND METHODS: Radiation oncologists of five European centres participated in the following consensus process: [1] revision of published (MEDLINE) and national/institutional delineation guidelines; [2] first delineation round of five cases (patient 1-5) according to national/institutional guidelines; [3] consensus meeting to discuss the results of step 1 and 2, followed by a target volume delineation proposal; [4] circulation of proposed instructions for target volume delineation and atlas for feedback; [5] second delineation round of five new cases (patient 6-10) to peer review and validate (two additional centres) the agreed delineation guidelines and atlas; [6] final consensus on the delineation guidelines depicted in an atlas. Target volumes of the delineation rounds were compared between centres by Dice similarity coefficient (DSC) and maximum/mean undirected Hausdorff distances (Hmax/Hmean). RESULTS: In the first delineation round, the consistency between centres was moderate (CTVtotal: DSC = 0.59-0.88; Hmean = 0.2-0.4 cm). Delineations in the second round were much more consistent. Lowest variability was obtained between centres participating in the consensus meeting (CTVtotal: DSC: p < 0.050 between rounds for patients 6/7/8/10; Hmean: p < 0.050 for patients 7/8/10), compared to validation centres (CTVtotal: DSC: p < 0.050 between validation and consensus meeting centres for patients 6/7/8; Hmean: p < 0.050 for patients 7/10). A proposal for delineation of target volumes and an atlas were generated. CONCLUSION: We proposed instructions for target volume delineation and an atlas for the neoadjuvant radiation treatment in oesophageal cancer. These will enable a more uniform delineation of patients in clinical practice and clinical trials.


Assuntos
Neoplasias Esofágicas , Terapia Neoadjuvante , Consenso , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/radioterapia , Humanos , Variações Dependentes do Observador , Radio-Oncologistas , Planejamento da Radioterapia Assistida por Computador
16.
J Epidemiol Community Health ; 74(10): 824-830, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32586986

RESUMO

BACKGROUND: Attrition, the loss of participants as a study progresses, is a considerable challenge in longitudinal studies. This study examined whether two forms of attrition, 'withdrawal' (formal discontinued participation) and 'non-response' (non-response among participants continuing in the study), have different associations with mortality and whether these associations differed across time in a multi-wave longitudinal study. METHODS: Participants were 10 012 civil servants who participated at the baseline of the Whitehall II cohort study with 11 data waves over an average follow-up of 28 years. We performed competing-risks analyses to estimate sub-distribution HRs and 95% CIs, and likelihood ratio tests to examine whether hazards differed between the two forms of attrition. We then applied linear regression to examine any trend of hazards against time. RESULTS: Attrition rate at data collections ranged between 13% and 34%. There were 495 deaths recorded from cardiovascular disease and 1367 deaths from other causes. Study participants lost due to attrition had 1.55 (95% CI 1.26 to 1.89) and 1.56 (1.39 to 1.76) times higher hazard of cardiovascular and non-cardiovascular mortality than responders, respectively. Hazards for withdrawal and non-response did not differ for either cardiovascular (p value =0.28) or non-cardiovascular mortality (p value =0.38). There was no linear trend in hazards over the 11 waves (cardiovascular mortality p value =0.11, non-cardiovascular mortality p value =0.61). CONCLUSION: Attrition can be a problem in longitudinal studies resulting in selection bias. Researchers should examine the possibility of selection bias and consider applying statistical approaches that minimise this bias.


Assuntos
Doenças Cardiovasculares , Mortalidade , Adulto , Viés , Doenças Cardiovasculares/mortalidade , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Reino Unido
17.
Environ Res Lett ; 152020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33850516

RESUMO

Cereals are an important component of the Indian diet, providing 47% of the daily dietary energy intake. Dwindling groundwater reserves in India especially in major cereal-growing regions are an increasing challenge to national food supply. An improved understanding of interstate cereal trade can help to identify potential risks to national food security. Here, we quantify the trade between Indian states of five major cereals and the associated trade in virtual (or embedded) water. To do this, we modelled interstate trade of cereals using Indian government data on supply and demand; calculated virtual water use of domestic cereal production using state- and product-specific water footprints and state-level data on irrigation source; and incorporated virtual water used in the production of internationally-imported cereals using country-specific water footprints. We estimate that 40% (94 million tonnes) of total cereal food supply was traded between Indian states in 2011-12, corresponding to a trade of 54.0 km3 of embedded blue water, and 99.4 km3 of embedded green water. Of the cereals traded within India, 41% were produced in states with over-exploited groundwater reserves (defined according to the Central Ground Water Board) and a further 21% in states with critically depleting groundwater reserves. Our analysis indicates a high dependency of Indian cereal consumption on production in states with stressed groundwater reserves. Substantial changes in agricultural practices and land use may be required to secure future production, trade and availability of cereals in India. Diversifying production systems could increase the resilience of India's food system.

18.
Health Place ; 57: 147-156, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31051326

RESUMO

Since the turn of the century there has been an explosion in the number of epidemiological studies that have analysed neighbourhood effects on health and wellbeing. The vast majority of these studies are cross-sectional in nature and assume that a contemporaneous place of residence captures a meaningful neighbourhood effect. Over the same time frame, social epidemiology has focussed increasingly on life course effects. This paper aims to bring these two areas of study together and tests whether there a certain ages during the life course when neighbourhoods are more important for our health and wellbeing than others. We use two British birth cohort studies (1958 National Child Development Study and British Cohort Study 1970) each comprising approximately 6,000 sample members at midlife linked to historic census measures used to derived Townsend neighbourhood deprivation scores over the life course. We find little evidence to support our hypothesis that adolescence is a key period of neighbourhood effect, rather we find late-early-adulthood neighbourhood deprivation and midlife neighbourhood deprivation are more strongly related to mid-life health and wellbeing. We are not able to conclude whether these effects are causal and encourage further investigation of selection mechanisms into neighbourhoods and mediation throughout the life course using our newly created dataset.


Assuntos
Disparidades nos Níveis de Saúde , Acontecimentos que Mudam a Vida , Características de Residência , Fatores Socioeconômicos , Adolescente , Adulto , Envelhecimento , Criança , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Apoio Social , Reino Unido
19.
J Am Coll Cardiol ; 69(9): 1160-1169, 2017 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-28254179

RESUMO

BACKGROUND: Neutrophil counts are a ubiquitous measure of inflammation, but previous studies on their association with cardiovascular disease (CVD) were limited by small numbers of patients or a narrow range of endpoints. OBJECTIVES: This study investigated associations of clinically recorded neutrophil counts with initial presentation for a range of CVDs. METHODS: We used linked primary care, hospitalization, disease registry, and mortality data in England. We included people 30 years or older with complete blood counts performed in usual clinical care and no history of CVD. We used Cox models to estimate cause-specific hazard ratios (HRs) for 12 CVDs, adjusted for cardiovascular risk factors and acute conditions affecting neutrophil counts (such as infections and cancer). RESULTS: Among 775,231 individuals in the cohort, 154,179 had complete blood counts performed under acute conditions and 621,052 when they were stable. Over a median 3.8 years of follow-up, 55,004 individuals developed CVD. Adjusted HRs comparing neutrophil counts 6 to 7 versus 2 to 3 × 109/l (both within the 'normal' range) showed strong associations with heart failure (HR: 2.04; 95% confidence interval [CI]: 1.82 to 2.29), peripheral arterial disease (HR: 1.95; 95% CI: 1.72 to 2.21), unheralded coronary death (HR: 1.78; 95% CI: 1.51 to 2.10), abdominal aortic aneurysm (HR: 1.72; 95% CI: 1.34 to 2.21), and nonfatal myocardial infarction (HR: 1.58; 95% CI: 1.42 to 1.76). These associations were linear, with greater risk even among individuals with neutrophil counts of 3 to 4 versus 2 to 3 × 109/l. There was a weak association with ischemic stroke (HR: 1.36; 95% CI: 1.17 to 1.57), but no association with stable angina or intracerebral hemorrhage. CONCLUSIONS: Neutrophil counts were strongly associated with the incidence of some CVDs, but not others, even within the normal range, consistent with underlying disease mechanisms differing across CVDs. (White Blood Cell Counts and Onset of Cardiovascular Diseases: a CALIBER Study [CALIBER]; NCT02014610).


Assuntos
Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Contagem de Leucócitos , Neutrófilos , Adulto , Idoso , Estudos de Coortes , Inglaterra/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais
20.
Artigo em Inglês | MEDLINE | ID: mdl-28320707

RESUMO

BACKGROUND: The relationship between procedural volume and prognosis after percutaneous coronary intervention (PCI) remains uncertain, with some studies finding in favor of an inverse association and some against. This UK study provides a contemporary reassessment in one of the few countries in the world with a nationally representative PCI registry. METHODS AND RESULTS: A nationwide cohort study was performed using the national British Cardiovascular Intervention Society registry. All adult patients undergoing PCI in 93 English and Welsh NHS hospitals between 2007 and 2013 were analyzed using hierarchical modeling with adjustment for patient risk. Of 427 467 procedures (22.0% primary PCI) in 93 hospitals, 30-day mortality was 1.9% (4.8% primary PCI). 87.1% of centers undertook between 200 and 2000 procedures annually. Case mix varied with center volume. In centers with 200 to 399 PCI cases per year, a smaller proportion were PCI for ST-segment-elevation myocardial infarction (8.4%) than in centers with 1500 to 1999 PCI cases per year (24.2%), but proportionally more were for ST-segment-elevation myocardial infarction with cardiogenic shock (8.4% versus 4.3%). For the overall PCI cohort, after risk adjustment, there was no significant evidence of worse, or better, outcomes in lower volume centers from our own study, or in combination with results from other studies. For primary PCI, there was also no evidence for increased or decreased mortality in lower volume centers. CONCLUSIONS: After adjustment for differences in case mix and clinical presentation, this study supports the conclusion of no trend for increased mortality in lower volume centers for PCI in the UK healthcare system. CLINICAL TRIAL REGISTRATION: https://www.clinicaltrials.gov. Unique identifier: NCT02184949.


Assuntos
Doença da Artéria Coronariana/terapia , Hospitais com Alto Volume de Atendimentos , Hospitais com Baixo Volume de Atendimentos , Intervenção Coronária Percutânea/mortalidade , Avaliação de Processos em Cuidados de Saúde , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Choque Cardiogênico/terapia , Idoso , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/mortalidade , Feminino , Hospitais com Alto Volume de Atendimentos/tendências , Hospitais com Baixo Volume de Atendimentos/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/tendências , Avaliação de Processos em Cuidados de Saúde/tendências , Sistema de Registros , Medição de Risco , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/mortalidade , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/mortalidade , Fatores de Tempo , Resultado do Tratamento , Reino Unido
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