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1.
Int J Obes (Lond) ; 42(4): 662-670, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29093538

RESUMO

BACKGROUND: The National Child Measurement Programme (NCMP) records weight and height and assesses overweight-obesity patterns in English children using body mass index (BMI), which tends to underestimate body fatness in South Asian children and overestimate body fatness in Black children of presumed African ethnicity. Using BMI adjustments to ensure that adjusted BMI was similarly related to body fatness in South Asian, Black and White children, we reassessed population overweight and obesity patterns in these ethnic groups in NCMP. METHODS: Analyses were based on 2012-2013 NCMP data in 582 899 children aged 4-5 years and 485 362 children aged 10-11 years. Standard centile-based approaches defined weight status in each age group before and after applying BMI adjustments for English South Asian and Black children derived from previous studies using the deuterium dilution method. FINDINGS: Among White children, overweight-obesity prevalences (boys, girls) were 23% and 21%, respectively, in 4-5 year olds and 33% and 30%, respectively, in 10-11 year olds. Before adjustment, South Asian children had lower overweight-obesity prevalences at 4-5 years (19%, 19%) and slightly higher prevalences at 10-11 years (42%, 34%), whereas Black children had higher overweight-obesity prevalences both at 4-5 years (31%, 29%) and 10-11 years (42%, 45%). Following adjustment, overweight-obesity prevalences were markedly higher in South Asian children both at 4-5 years (39%, 35%) and at 10-11 years (52%, 44%), whereas Black children had lower prevalences at 4-5 years (11%, 12%); at 10-11 years, prevalences were slightly lower in boys (32%) but higher in girls (35%). INTERPRETATION: BMI adjustments revealed extremely high overweight-obesity prevalences among South Asian children in England, which were not apparent in unadjusted data. In contrast, after adjustment, Black children had lower overweight-obesity prevalences except among older girls. FUNDING: British Heart Foundation, NIHR CLAHRC (South London), NIHR CLAHRC (North Thames).


Assuntos
Povo Asiático/estatística & dados numéricos , População Negra/estatística & dados numéricos , Índice de Massa Corporal , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Tecido Adiposo/fisiologia , Povo Asiático/etnologia , População Negra/etnologia , Peso Corporal/etnologia , Peso Corporal/fisiologia , Criança , Pré-Escolar , Estudos de Coortes , Inglaterra/epidemiologia , Feminino , Humanos , Masculino , Sobrepeso/etnologia , Obesidade Infantil/etnologia
2.
Int J Obes (Lond) ; 41(7): 1048-1055, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28325931

RESUMO

BACKGROUND/OBJECTIVES: Body mass index (BMI) (weight per height2) is the most widely used marker of childhood obesity and total body fatness (BF). However, its validity is limited, especially in children of South Asian and Black African origins. We aimed to quantify BMI adjustments needed for UK children of Black African and South Asian origins so that adjusted BMI related to BF in the same way as for White European children. METHODS: We used data from four recent UK studies that made deuterium dilution BF measurements in UK children of White European, South Asian and Black African origins. A height-standardized fat mass index (FMI) was derived to represent BF. Linear regression models were then fitted, separately for boys and girls, to quantify ethnic differences in BMI-FMI relationships and to provide ethnic-specific BMI adjustments. RESULTS: We restricted analyses to 4-12 year olds, to whom a single consistent FMI (fat mass per height5) could be applied. BMI consistently underestimated BF in South Asians, requiring positive BMI adjustments of +1.12 kg m-2 (95% confidence interval (CI): 0.83, 1.41 kg m-2; P<0.0001) for boys and +1.07 kg m-2 (95% CI: 0.74, 1.39 kg m-2; P<0.0001) for girls of all age groups and FMI levels. BMI overestimated BF in Black Africans, requiring negative BMI adjustments for Black African children. However, these were complex because there were statistically significant interactions between Black African ethnicity and FMI (P=0.004 boys; P=0.003 girls) and also between FMI and age group (P<0.0001 for boys and girls). BMI adjustments therefore varied by age group and FMI level (and indirectly BMI); the largest adjustments were in younger children with higher unadjusted BMI and the smallest in older children with lower unadjusted BMI. CONCLUSIONS: BMI underestimated BF in South Asians and overestimated BF in Black Africans. Ethnic-specific adjustments, increasing BMI in South Asians and reducing BMI in Black Africans, can improve the accuracy of BF assessment in these children.


Assuntos
Tecido Adiposo , Adiposidade/etnologia , Povo Asiático , População Negra , Índice de Massa Corporal , Obesidade Infantil/prevenção & controle , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Obesidade Infantil/diagnóstico , Padrões de Referência , Reprodutibilidade dos Testes , Reino Unido
3.
Diabet Med ; 33(3): 307-15, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26498636

RESUMO

AIM: To examine whether low circulating vitamin C concentrations and low fruit and vegetable intakes were associated with insulin resistance and other Type 2 diabetes risk markers in childhood. METHODS: We conducted a cross-sectional, school-based study in 2025 UK children aged 9-10 years, predominantly of white European, South-Asian and black African origin. A 24-h dietary recall was used to assess fruit, vegetable and vitamin C intakes. Height, weight and fat mass were measured and a fasting blood sample collected to measure plasma vitamin C concentrations and Type 2 diabetes risk markers. RESULTS: In analyses adjusting for confounding variables (including socio-economic status), a one interquartile range higher plasma vitamin C concentration (30.9 µmol/l) was associated with a 9.6% (95% CI 6.5, 12.6%) lower homeostatic model assessment of insulin resistance value, 0.8% (95% CI 0.4, 1.2%) lower fasting glucose, 4.5% (95% CI 3.2, 5.9%) lower urate and 2.2% (95% CI 0.9, 3.4%) higher HDL cholesterol. HbA1c concentration was 0.6% (95% CI 0.2, 1.0%) higher. Dietary fruit, vegetable and total vitamin C intakes were not associated with any Type 2 diabetes risk markers. Lower plasma vitamin C concentrations in South-Asian and black African-Caribbean children could partly explain their higher insulin resistance. CONCLUSIONS: Lower plasma vitamin C concentrations are associated with insulin resistance and could partly explain ethnic differences in insulin resistance. Experimental studies are needed to establish whether increasing plasma vitamin C can help prevent Type 2 diabetes at an early stage.


Assuntos
Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Glicemia/metabolismo , Ingestão de Alimentos/fisiologia , Frutas , Resistência à Insulina , Verduras , Criança , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/etiologia , Dieta , Feminino , Humanos , Masculino , Fatores de Risco , Fatores Socioeconômicos , Reino Unido/epidemiologia
4.
Diabetologia ; 53(8): 1620-30, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20454952

RESUMO

AIMS/HYPOTHESIS: Physical inactivity is implicated in unfavourable patterns of obesity and cardiometabolic risk in childhood. However, few studies have quantified these associations using objective physical activity measurements in children from different ethnic groups. We examined these associations in UK children of South Asian, black African-Caribbean and white European origin. METHODS: This was a cross-sectional study of 2,049 primary school children in three UK cities, who had standardised anthropometric measurements, provided fasting blood samples and wore activity monitors for up to 7 days. Data were analysed using multilevel linear regression and allowing for measurement error. RESULTS: Overall physical activity levels showed strong inverse graded associations with adiposity markers (particularly sum of skinfold thicknesses), fasting insulin, HOMA insulin resistance, triacylglycerol and C-reactive protein; for an increase of 100 counts of physical activity per min of registered time, levels of these factors were 12.2% (95% CI 10.2-14.1%), 10.2% (95% CI 7.5-12.8%), 10.2% (95% CI 7.5-12.8%), 5.8% (95% CI 4.0-7.5%) and 19.2% (95% CI 13.9-24.2%) lower, respectively. Similar increments in physical activity levels were associated with lower diastolic blood pressure (1.0 mmHg, 95% CI 0.6-1.5 mmHg) and LDL-cholesterol (0.04 mmol/l, 95% CI 0.01-0.07 mmol/l), and higher HDL-cholesterol (0.02 mmol/l, 95% CI 0.01-0.04 mmol/l). Moreover, associations were broadly similar in strength in all ethnic groups. All associations between physical activity and cardiometabolic risk factors were reduced (albeit variably) after adjustment for adiposity. CONCLUSIONS/INTERPRETATION: Objectively measured physical activity correlates at least as well with obesity and cardiometabolic risk factors in South Asian and African-Caribbean children as in white European children, suggesting that efforts to increase activity levels in such groups would have equally beneficial effects.


Assuntos
Adiposidade/fisiologia , Atividade Motora/fisiologia , Obesidade/epidemiologia , Povo Asiático , População Negra , Doenças Cardiovasculares/fisiopatologia , Criança , Proteção da Criança , Estudos Transversais , Inglaterra/epidemiologia , Feminino , Humanos , Resistência à Insulina , Masculino , Obesidade/fisiopatologia , Risco , Fatores de Risco , Dobras Cutâneas , Classe Social , População Branca
5.
Br J Nutr ; 104(2): 276-85, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20230652

RESUMO

In the UK, South Asian adults have increased risks of CHD, type 2 diabetes and central obesity. Black African-Caribbeans, in contrast, have increased risks of type 2 diabetes and general obesity but lower CHD risk. There is growing evidence that these risk differences emerge in early life and that nutritional factors may be important. We have therefore examined the variations in nutritional composition of the diets of South Asian, black African-Caribbean and white European children, using 24 h recalls of dietary intake collected during a cross-sectional survey of cardiovascular health in eighty-five primary schools in London, Birmingham and Leicester. In all, 2209 children aged 9-10 years took part, including 558 of South Asian, 560 of black African-Caribbean and 543 of white European ethnicity. Compared with white Europeans, South Asian children reported higher mean total energy intake; their intakes of total fat, polyunsaturated fat and protein (both absolute and as proportions of total energy intake) were higher and their intakes of carbohydrate as a proportion of energy (particularly sugars), vitamin C and D, Ca and haem Fe were lower. These differences were especially marked for Bangladeshi children. Black African-Caribbean children had lower intakes of total and saturated fat (both absolute and as proportions of energy intake), NSP, vitamin D and Ca. The lower total and saturated fat intakes were particularly marked among black African children. Appreciable ethnic differences exist in the nutritional composition of children's diets, which may contribute to future differences in chronic disease risk.


Assuntos
População Negra , Dieta/etnologia , Comportamento Alimentar/etnologia , População Branca , Ásia Ocidental/etnologia , Região do Caribe/etnologia , Criança , Dieta/estatística & dados numéricos , Humanos , Avaliação Nutricional , Reino Unido
6.
Andrology ; 8(2): 323-331, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31380611

RESUMO

BACKGROUND: Relatively low sperm count was reported among young Spanish men in 2013. Several potential culprits have been suggested as explanations for reported trends in sperm counts in Western men, including lifestyles. Although controversial, some studies suggest that semen parameters, such as low sperm motility or abnormal morphology, may be associated with low serum vitamin D levels. OBJECTIVES: To evaluate associations between semen parameters and reproductive hormones and serum 25-hydroxyvitamin D (25OHD) status in young Spanish men and to examine these associations in relation to dietary intake of vitamin D. MATERIALS AND METHODS: This cross-sectional study includes 198 university students recruited in 2010-2011 in southern Spain, who provided samples of blood and semen and food frequencies. Semen quality was evaluated by measuring volume, concentration, sperm counts, motility, and morphology, according to the WHO guidelines. Serum samples were analyzed for total 25OHD and reproductive hormones, including FSH, LH, testosterone, inhibin B, and estradiol. Dietary vitamin D intake was assessed using a validated food frequency questionnaire. Associations with semen quality and reproductive hormones were examined using linear regression, adjusting for potential confounders. RESULTS: Almost all men had adequate levels of serum vitamin D - only three men (1.5%) were vitamin D deficient (<30 nmol/L) and 17% were insufficient (<50 nmol/L). However, dietary vitamin D intakes were relatively low (below recommended 600 IU/day in 99% of men). Neither dietary intake nor serum vitamin D levels were associated with any sperm parameter or any reproductive hormone (all p ≥ 0.09). DISCUSSION: We did not observe an association between vitamin D status and any reproductive parameter in our study population. CONCLUSIONS: Our results suggest that serum vitamin D levels are sustained in Spanish men despite low dietary intake and therefore low vitamin D does not explain the poor semen quality previously observed in these young Spanish men.


Assuntos
Dieta , Análise do Sêmen , Motilidade dos Espermatozoides/fisiologia , Vitamina D/análogos & derivados , Adolescente , Estudos Transversais , Humanos , Masculino , Espanha , Vitamina D/sangue , Adulto Jovem
7.
Thorax ; 64(8): 657-63, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19359266

RESUMO

BACKGROUND: The extent to which chronic exposure to outdoor air pollutants influences lung function in adults is unclear. The aim of this study was to measure the association between chronic exposure to outdoor air pollutants and adult lung function. METHODS: The relationship between measures of lung function (forced expiratory volume in 1 s (FEV(1)) and FEV(1) as a percentage of forced vital capacity (FVC)) and average exposure to particulate matter <10 microm in diameter, nitrogen dioxide, sulfur dioxide and ozone was examined in four representative cross-sectional surveys of the English population aged > or =16 in 1995, 1996, 1997 and 2001. Year-specific estimates were pooled using fixed effects meta-analysis. RESULTS: Greater exposure to particulate matter <10 microm in diameter, nitrogen dioxide and sulfur dioxide was associated with lower adult FEV(1). The size of the effect on population mean FEV(1) was about 3% for particulate matter <10 microm, and 0.7% for nitrogen dioxide and sulfur dioxide, for a 10 microg/m(3) increase in pollutant concentration. The effects were most marked in men, older adults and ex-smokers. FEV(1) was not associated with ozone concentration. No associations were found between the pollutants and FEV(1) as a percentage of FVC. CONCLUSIONS: Chronic exposure to outdoor air pollution is associated with modestly reduced FEV(1) in adults.


Assuntos
Poluentes Atmosféricos/análise , Exposição Ambiental/análise , Volume Expiratório Forçado/fisiologia , Pulmão/fisiologia , Capacidade Vital/fisiologia , Adolescente , Adulto , Idoso , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dióxido de Nitrogênio/análise , Ozônio/análise , Material Particulado/análise , Dióxido de Enxofre/análise , Adulto Jovem
8.
Int J Obes (Lond) ; 33(8): 866-77, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19506565

RESUMO

OBJECTIVE: Although obesity beginning early in life is becoming more common, its implications for coronary heart disease (CHD) risk in later life remain uncertain. We examined the relationship of body mass index (BMI) before 30 years of age to CHD risk in later life. DESIGN: Systematic review of published studies relating BMI between age 2 and 30 years to later CHD risk. Studies were identified using Medline (1950 onwards), Embase (1980 onwards) and Web of Science (1970 onwards) databases (to November 2007). MEASUREMENTS: Relative risks (RR) of CHD associated with a 1 standard deviation (s.d.) higher BMI (most based on a narrow age range at measurement) were extracted by two authors independently, and combined using random-effect models. RESULTS: A total of 15 studies provided 17 estimates (731 337 participants, 23 894 CHD events) of the association of early BMI to later CHD outcome. BMI in early childhood (2-6 years, 3 estimates) showed a weak inverse association with CHD risk (RR 0.94, 95% CI 0.82-1.07). BMI in later childhood (7 to <18 years, 7 estimates) and BMI in early adult life (18-30 years, 7 estimates) were both positively related to later CHD risk (RR 1.09, 95% CI 1.00-1.20; RR 1.19, 95% CI 1.11-1.29 respectively). However, there was considerable statistical heterogeneity between study estimates. Results were unaffected by adjustment for social class and/or cigarette smoking, blood pressure and/or total cholesterol, in studies with available data. Gender and year of birth (1900-1976) had little effect on the association. CONCLUSIONS: BMI is positively related to CHD risk from childhood onwards; the associations in young adults are consistent with those observed in middle age. Long-term control of BMI from childhood may be important to reduce the risk of CHD.


Assuntos
Índice de Massa Corporal , Doença das Coronárias/etiologia , Obesidade/complicações , Fumar/efeitos adversos , Adolescente , Adulto , Fatores Etários , Criança , Pré-Escolar , Medicina Baseada em Evidências , Feminino , Humanos , Masculino , Fatores de Risco , Reino Unido/epidemiologia , Adulto Jovem
9.
Eur Respir J ; 32(1): 77-84, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18321940

RESUMO

Recent research has suggested an association between circulating C-reactive protein (CRP) and adult asthma, confined to those without evidence of allergic predisposition. The current authors investigated the role of smoking and obesity as possible explanations for this relationship. At 44-45 yrs of age, members of the British 1958 birth cohort participated in a biomedical survey involving the measurement of the following: CRP; the specific immunoglobulin E to grass, cat and dust mite; standing height; and weight. Information on asthma and related symptoms was collected by computer-aided interview when the subjects were 42 yrs of age. Complete data were available for a total of 6,490 subjects. CRP levels were positively correlated with the body mass index (BMI) and were found to be higher among females when compared with males, and higher among heavy smokers (> or = 20 cigarettes x day(-1)) when compared with never-smokers. After adjustment for sex and region, the odds ratios, comparing asthma prevalence in subjects above the fourth CRP quartile with subjects below the first quartile, were 1.85 (95% confidence interval 1.15-2.99) for nonatopics and 0.94 (0.62-1.41) for atopics, changing to 1.36 (0.80-2.32) and 1.07 (0.67-1.69), respectively, when additionally adjusted for smoking and BMI. Any association between C-reactive protein and asthma prevalence confined to nonatopics may be due to confounding factors. Alternatively, it may reflect a more general association of C-reactive protein with smoking-related obstructive airways disease.


Assuntos
Asma/complicações , Proteína C-Reativa/análise , Hipersensibilidade/complicações , Obesidade/complicações , Fumar/efeitos adversos , Adulto , Asma/sangue , Asma/epidemiologia , Índice de Massa Corporal , Feminino , Humanos , Hipersensibilidade/sangue , Hipersensibilidade/epidemiologia , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/epidemiologia , Razão de Chances , Prevalência , Fumar/sangue , Reino Unido/epidemiologia
10.
Comput Biol Med ; 90: 23-32, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28917120

RESUMO

The morphometric characteristics of the retinal vasculature are associated with future risk of many systemic and vascular diseases. However, analysis of data from large population based studies is needed to help resolve uncertainties in some of these associations. This requires automated systems that extract quantitative measures of vessel morphology from large numbers of retinal images. Associations between retinal vessel morphology and disease precursors/outcomes may be similar or opposing for arterioles and venules. Therefore, the accurate detection of the vessel type is an important element in such automated systems. This paper presents a deep learning approach for the automatic classification of arterioles and venules across the entire retinal image, including vessels located at the optic disc. This comprises of a convolutional neural network whose architecture contains six learned layers: three convolutional and three fully-connected. Complex patterns are automatically learnt from the data, which avoids the use of hand crafted features. The method is developed and evaluated using 835,914 centreline pixels derived from 100 retinal images selected from the 135,867 retinal images obtained at the UK Biobank (large population-based cohort study of middle aged and older adults) baseline examination. This is a challenging dataset in respect to image quality and hence arteriole/venule classification is required to be highly robust. The method achieves a significant increase in accuracy of 8.1% when compared to the baseline method, resulting in an arteriole/venule classification accuracy of 86.97% (per pixel basis) over the entire retinal image.


Assuntos
Bancos de Espécimes Biológicos , Bases de Dados Factuais , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Disco Óptico , Vasos Retinianos/diagnóstico por imagem , Arteríolas/diagnóstico por imagem , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Disco Óptico/irrigação sanguínea , Disco Óptico/diagnóstico por imagem , Reino Unido , Vênulas/diagnóstico por imagem
11.
J Thromb Haemost ; 4(11): 2405-10, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17002654

RESUMO

BACKGROUND: As with 'conventional' risk factors such as cholesterol and smoking, there is a need for large, long-term prospective studies on hemostatic factors. OBJECTIVES: To investigate the prospective relationship of fibrinogen and factor VII clotting activity (FVIIc) with risk of coronary heart disease (CHD) and stroke in a study with a large number of outcomes over a period of 15 years. PATIENTS/METHODS: A cohort of 22 715 men aged 45-69 years was screened for participation in the Thrombosis Prevention Trial. Men were followed up for fatal and non-fatal CHD and stroke events. There were 1515 CHD events (933 CHD deaths) and 391 strokes (180 stroke deaths). Hazard ratios (HRs) and 95% confidence intervals are expressed per standardized increase in log fibrinogen and log FVIIc, adjusting for age, trial treatment group, conventional CHD risk factors and regression dilution bias. RESULTS: Hazard ratios for fibrinogen were 1.52 (1.37-1.70) for all CHD events, and 1.36 (1.09-1.69) for all strokes. Exclusion of events within the first 10 years showed a persistent association between CHD and fibrinogen, with an adjusted HR of 1.93 (1.42-2.64). The HRs for FVIIc, adjusting for age and trial treatment, were 1.07 (1.01-1.12) for all CHD events and 1.07 (0.97-1.20) for all strokes, and the fully adjusted HRs were, respectively, 0.97 (0.84-1.05) and 1.07 (0.85-1.33). CONCLUSIONS: The persisting association between fibrinogen and CHD beyond 10 years may imply a causal effect. There is a small effect of FVIIc on CHD, after adjustment for age and trial treatment, but no association independent of other risk factors.


Assuntos
Doença das Coronárias/sangue , Fator VII/análise , Fibrinogênio/análise , Acidente Vascular Cerebral/sangue , Fatores Etários , Idoso , Doença das Coronárias/mortalidade , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/mortalidade , Trombose/sangue , Trombose/prevenção & controle
12.
Comput Biol Med ; 71: 67-76, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26894596

RESUMO

Morphological changes in the retinal vascular network are associated with future risk of many systemic and vascular diseases. However, uncertainty over the presence and nature of some of these associations exists. Analysis of data from large population based studies will help to resolve these uncertainties. The QUARTZ (QUantitative Analysis of Retinal vessel Topology and siZe) retinal image analysis system allows automated processing of large numbers of retinal images. However, an image quality assessment module is needed to achieve full automation. In this paper, we propose such an algorithm, which uses the segmented vessel map to determine the suitability of retinal images for use in the creation of vessel morphometric data suitable for epidemiological studies. This includes an effective 3-dimensional feature set and support vector machine classification. A random subset of 800 retinal images from UK Biobank (a large prospective study of 500,000 middle aged adults; where 68,151 underwent retinal imaging) was used to examine the performance of the image quality algorithm. The algorithm achieved a sensitivity of 95.33% and a specificity of 91.13% for the detection of inadequate images. The strong performance of this image quality algorithm will make rapid automated analysis of vascular morphometry feasible on the entire UK Biobank dataset (and other large retinal datasets), with minimal operator involvement, and at low cost.


Assuntos
Algoritmos , Aumento da Imagem/métodos , Retina/patologia , Vasos Retinianos/patologia , Doenças Vasculares/patologia , Adulto , Idoso , Conjuntos de Dados como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distribuição Aleatória , Reino Unido
13.
BMJ Open ; 6(6): e011131, 2016 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-27324713

RESUMO

OBJECTIVE: Little is known about levels of physical fitness in children from different ethnic groups in the UK. We therefore studied physical fitness in UK children (aged 9-10 years) of South Asian, black African-Caribbean and white European origin. DESIGN: Cross-sectional study. SETTING: Primary schools in the UK. PARTICIPANTS: 1625 children (aged 9-10 years) of South Asian, black African-Caribbean and white European origin in the UK studied between 2006 and 2007. OUTCOME MEASURES: A step test assessed submaximal physical fitness from which estimated VO2 max was derived. Ethnic differences in estimated VO2 max were estimated using multilevel linear regression allowing for clustering at school level and adjusting for age, sex and month as fixed effects. RESULTS: The study response rate was 63%. In adjusted analyses, boys had higher levels of estimated VO2 max than girls (mean difference 3.06 mL O2/min/kg, 95% CI 2.66 to 3.47, p<0.0001). Levels of estimated VO2 max were lower in South Asians than those in white Europeans (mean difference -0.79 mL O2/min/kg, 95% CI -1.41 to -0.18, p=0.01); levels of estimated VO2 max in black African-Caribbeans were higher than those in white Europeans (mean difference 0.60 mL O2/min/kg, 95% CI 0.02 to 1.17, p=0.04); these patterns were similar in boys and girls. The lower estimated VO2 max in South Asians, compared to white Europeans, was consistent among Indian, Pakistani and Bangladeshi children and was attenuated by 78% after adjustment for objectively measured physical activity (average daily steps). CONCLUSIONS: South Asian children have lower levels of physical fitness than white Europeans and black African-Caribbeans in the UK. This ethnic difference in physical fitness is at least partly explained by ethnic differences in physical activity.


Assuntos
Povo Asiático/estatística & dados numéricos , População Negra/estatística & dados numéricos , Aptidão Física , População Branca/estatística & dados numéricos , Criança , Estudos Transversais , Inglaterra/etnologia , Teste de Esforço , Feminino , Humanos , Modelos Lineares , Masculino , Consumo de Oxigênio , Instituições Acadêmicas
14.
Semin Perinatol ; 29(4): 225-35, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16104673

RESUMO

BACKGROUND: Until the publication of the Serum Urine and Ultrasound Screening Study (SURUSS) report, it was difficult to compare the different antenatal screening tests for Down's Syndrome because of variations in study designs. We here present the main results from SURUSS, updated to take account of recent information on nuchal translucency in Down's Syndrome pregnancies, and discuss their implications. METHODS: SURUSS was a prospective study of 47,053 singleton pregnancies (including 101 pregnancies with Down's Syndrome) conducted in 25 maternity units. Nuchal translucency measurements were taken. Serum and urine samples collected between 9 and 13 weeks, and again between 14 and 20 weeks of pregnancy were stored. Samples from each affected pregnancy and five matched controls were tested for currently used or suggested biochemical Down's Syndrome screening markers. Pregnancies were followed up to determine the presence or absence of Down's Syndrome. For an 85% Down's Syndrome detection rate, the false-positive rate for the Integrated test (nuchal translucency and pregnancy associated plasma protein-A [PAPP-A] at 11 completed weeks of pregnancy, and alpha-fetoprotein, unconjugated oestriol [uE3], free beta or total human chorionic gonadotrophin (hCG) and inhibin-A in the early second trimester) was 0.9%, the Serum integrated test (without nuchal translucency) 2.7%, the Combined test (nuchal translucency with free beta-hCG and PAPP-A at 11 weeks) 4.3%, the Quadruple test (alpha-fetoprotein, uE3, free beta or total hCG and inhibin-A) 6.2%, and nuchal translucency at 11 weeks, 15.2%. All tests included maternal age. Using the Integrated test at an 85% detection rate, there would be six diagnostic procedure-related unaffected fetal losses following amniocentesis per 100,000 women screened compared with 35 using the Combined test or 45 with the Quadruple test. CONCLUSIONS: The Integrated test offers the most effective and safe method of screening for women who attend in the first trimester. The next best test is the Serum integrated test. The Quadruple test is the best test for women who first attend in the second trimester. There is no justification for retaining the Double (alpha-fetoprotein and hCG) or Triple (alpha-fetoprotein, uE3, and hCG) tests, or nuchal translucency alone (with or without maternal age) in antenatal screening for Down's Syndrome.


Assuntos
Síndrome de Down/diagnóstico , Doenças Fetais/diagnóstico , Segundo Trimestre da Gravidez , Diagnóstico Pré-Natal/métodos , Estudos de Casos e Controles , Gonadotropina Coriônica/sangue , Gonadotropina Coriônica/urina , Estudos de Coortes , Síndrome de Down/sangue , Síndrome de Down/diagnóstico por imagem , Síndrome de Down/urina , Estriol/sangue , Reações Falso-Positivas , Feminino , Doenças Fetais/sangue , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/urina , Humanos , Inibinas/sangue , Idade Materna , Medição da Translucência Nucal/métodos , Valor Preditivo dos Testes , Gravidez , Primeiro Trimestre da Gravidez , Proteína Plasmática A Associada à Gravidez/metabolismo , Estudos Prospectivos , alfa-Fetoproteínas/metabolismo
15.
Artigo em Inglês | MEDLINE | ID: mdl-26737473

RESUMO

The characteristics of the retinal vascular network have been prospectively associated with many systemic and vascular diseases. QUARTZ is a fully automated software that has been developed to localize and quantify the morphological characteristics of blood vessels in retinal images for use in epidemiological studies. This software was used to analyse a dataset containing 16,000 retinal images from the EPIC-Norfolk cohort study. The objective of this paper is to both assess the suitability of this dataset for computational analysis and to further evaluate the QUARTZ software.


Assuntos
Bases de Dados Factuais , Processamento de Imagem Assistida por Computador/métodos , Vasos Retinianos/anatomia & histologia , Software , Humanos
16.
Thromb Res ; 101(2): 1-11, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11342201

RESUMO

Protein S is a vitamin K-dependent protein with anticoagulant properties. Case series have reported reduced plasma concentrations in patients with arterial thromboses, while other studies have reported increased levels in patients with coronary heart disease (CHD). The present study sought to clarify the relation between free protein S and risk of CHD. A prospective survey was conducted of 3000 men aged 50 to 61 years, free of clinical CHD at baseline. Free protein S was measured by commercial immunoassay. End-points recorded were sudden coronary death, first nonfatal and fatal myocardial infarction (MI), surgical intervention for symptomatic, angiographically demonstrated CHD, and all-causes mortality. Statistical analysis employed univariate incidence rate ratios followed by Cox proportional hazards regression. There were 168 CHD events recorded during 21,000 person-years of risk. Mean free protein S concentration was 6% higher in those who developed CHD than in the remainder, the crude hazard ratio (HR) for a one standard deviation (S.D.) increase in free protein S being 1.25 (95% CI, 1.08-1.25). Free protein S was associated with cholesterol concentration and other conventional CHD risk factors. In multivariate regression analysis, after adjustment for conventional CHD risk factors a 1 S.D. increase in free protein S was associated with a HR of 1.15 (0.98-1.35) for CHD, of borderline conventional statistical significance. This association of free protein S with risk of CHD may reflect effects of plaque-destabilising inflammatory activity on protein S levels.


Assuntos
Doença das Coronárias/epidemiologia , Doença das Coronárias/etiologia , Proteína S/análise , Análise de Variância , Estudos de Coortes , Doença das Coronárias/sangue , Humanos , Imunoensaio , Incidência , Lipídeos/sangue , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
17.
Br J Ophthalmol ; 87(3): 312-7, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12598445

RESUMO

AIMS: To predict the burden of blindness, partial sight, and visual impairment (binocular visual acuity 6/18 or less) due to late stage age related macular degeneration (AMD) in the ageing population of the United Kingdom. METHODS: A systematic review, followed by a request for data, was used to establish a pooled prevalence of AMD and corresponding visual loss. Prevalence figures were applied to the UK population. Using UK population trends, the future burden of AMD over the coming decade was established. RESULTS: Pooled data from six studies showed that the prevalence of visual loss caused by AMD increased exponentially from the age of 70-85 years of age, with 3.5% (95% CI 3.0 to 4.1) having visual impairment beyond the age of 75 years. The authors estimate that there are currently 214 000 (95% CI 151 000 to 310 000) with visual impairment caused by AMD (suitable for registration). This number is expected to increase to 239 000 (95% CI 168 000 to 346 000) by the year 2011. Currently there are 172 000 (95% CI 106 000 to 279 000) and 245 000 (95% CI 163 000 to 364 000) with geographical and neovascular AMD, respectively. CONCLUSIONS: Estimates of visual impairment agree with official statistics for the number registered partially sighted or blind, caused by AMD, and are well below other figures often cited. Although these estimates are associated with wide confidence intervals (CI) and a number of caveats, they represent the best available data, which can be used to guide health and social care provision for older people in the UK setting. Implications for low vision services are outlined.


Assuntos
Degeneração Macular/epidemiologia , Transtornos da Visão/epidemiologia , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Cegueira/epidemiologia , Cegueira/etiologia , Feminino , Planejamento em Saúde/organização & administração , Humanos , Degeneração Macular/complicações , Masculino , Prevalência , Reino Unido/epidemiologia , Transtornos da Visão/etiologia , Acuidade Visual
18.
Br J Ophthalmol ; 82(6): 643-9, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9797665

RESUMO

AIMS: To compare methods available to correct the magnification of images that result from the optics of the eye and identify errors, and source of error, of the methods. METHODS: 11 methods were applied to ocular biometry data from three independent cohorts. Each method was compared with the method of Bennett, which uses most biometric data. The difference between each method and Bennett's is the "error" of the method. The relation between the error and axial length, ametropia, and keratometry was explored by linear regression analysis. RESULTS: Methods using axial length had the lowest mean (+0.5 to +2.6%) and standard deviation (0.6 to 1.2%) of errors. Of methods using keratometry and ametropia only, the lowest mean (-1.4% to +4.4%) and standard deviation (2.9 to 4.3%) of errors was found for a new method described in this paper, and that used by the Heidelberg retina tomograph (HRT). The highest mean error (+2.2 to +7.1%) was found for Littmann's method. Littmann's correction was larger than the HRT's by 3.5 to 3.7%. The mean difference between the new and HRT methods and the "abbreviated axial length" method of Bennett is -1.3 to +2.0%. The error of the "keratometry and ametropia" methods is related to axial length. CONCLUSIONS: Methods using axial length are most accurate. The abbreviated axial length method of Bennett differs little from more detailed calculations and is appreciably more accurate than methods using keratometry and ametropia alone. If axial length is unknown, the new and the HRT methods give results closest to the abbreviated axial length method.


Assuntos
Glaucoma/patologia , Hipertensão Ocular/patologia , Disco Óptico/patologia , Optometria/métodos , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oftalmologia/métodos , Óptica e Fotônica , Refração Ocular , Sensibilidade e Especificidade , Tonometria Ocular/métodos
19.
Folia Neuropathol ; 37(1): 43-51, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10337063

RESUMO

The spirochete Borrelia burgdorferi (B. burgdorferi) may cause severe meningoencephalomyelitis as the sole manifestation of Lyme borreliosis. We would like to present three such cases, where definite neuroborreliosis was clinically diagnosed in two cases and possible neuroborreliosis was recognized in one case. Alive spirochetes were isolated and cultured from blood and cerebrospinal fluid (CSF) in both definite cases. B. burgdorferi as the causative agent of the infection was confirmed in CSF by polymerase chain reaction (PCR) in one definite case. In the possible case spirochetes were cultured from blood and CSF. Alive spirochetes were not isolated, however anti-B. burgdorferi antibody value in serum was significantly elevated. On necropsy gross examination brain edema without focal changes was detected in two cases. Cerebral atrophy was seen in Case 3. Microscopically, lymphocytic infiltrates, microglial diffuse and nodular activation, spongiform changes, diffuse demyelination of the cerebral and cerebellar white matter, and diffuse astrocytosis, were characteristic pathological features in all presented cases. Multifocal, perivascular degenerative changes in the cerebral and cerebellar white matter were observed in the first case. Inflammatory changes in the nuclei and roots of cranial nerves were present in the third case.


Assuntos
Grupo Borrelia Burgdorferi/isolamento & purificação , Encefalomielite/patologia , Encefalomielite/parasitologia , Doença de Lyme/parasitologia , Adulto , Autopsia , Humanos , Masculino
20.
Przegl Epidemiol ; 47(3): 243-7, 1993.
Artigo em Polonês | MEDLINE | ID: mdl-8234841

RESUMO

This study presents the course of acute hepatitis B in 77 children. It has been recorded that the course of HBV infections in children is most often mild, and in children younger than 2 years of age it is usually inapparent. The most frequent markers of the infection are antigens HBs and HBe. ALAT in all children normalized 2 months at the longest, after the hospitalization had ended. The most considerable danger of carrier-state exists in children not older than 2 years of age; an increased danger of becoming a carrier exists during the time of pubescence. The main cause of HBV infections is hospital stay. There emerges a necessity of routine marking the HBs antigen in hospitalized children.


Assuntos
Hepatite B/diagnóstico , Adolescente , Biomarcadores/análise , Portador Sadio , Criança , Pré-Escolar , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/transmissão , Feminino , Hepatite B/etiologia , Antígenos da Hepatite B/análise , Humanos , Lactente , Masculino
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