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Prevalence of asthma symptoms in Latin America: the International Study of Asthma and Allergies in Childhood (ISAAC).(John Wiley & Sons, 2000-12-01)The prevalence of respiratory symptoms indicative of asthma in children from Latin America has been largely ignored. As part of the International Study of Asthma and Allergies in Childhood (ISAAC), 17 centers in 9 different Latin American countries participated in the study, and data from 52,549 written questionnaires (WQ) in children aged 13-14 years and from 36,264 WQ in 6-7 year olds are described here. In children aged 13-14 years, the prevalence of asthma ever ranged from 5.5-28%, and the prevalence of wheezing in the last 12 months from 6.6-27%. In children aged 6-7 years, the prevalence of asthma ever ranged from 4.1-26.9%, and the prevalence of wheezing in the last 12 months ranged from 8.6-32.1%. The lower prevalence in centers with higher levels of atmospheric pollution suggests that chronic inhalation of polluted air in children does not contribute to asthma. Furthermore, the high figures for asthma in a region with a high level of gastrointestinal parasite infestation, and a high burden of acute respiratory infections occurring early in life, suggest that these factors, considered as protective in other regions, do not have the same effect in this region. The present study indicates that the prevalence of asthma and related symptoms in Latin America is as high and variable as described in industrialized or developed regions of the world.Acceso restringido temporalmente
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Asthma control in Latin America: the Asthma Insights and Reality in Latin America (AIRLA) survey.(Pan American Health Organization, 2005-03-01)Objectives. The aims of this survey were (1) to assess the quality of asthma treatment and control in Latin America, (2) to determine how closely asthma management guidelines are being followed, and (3) to assess perception, knowledge and attitudes related to asthma in Latin America. Methods. We surveyed a household sample of 2 184 adults or parents of children with asthma in 2003 in 11 countries in Latin America. Respondents were asked about healthcare utilization, symptom severity, activity limitations and medication use. Results. Daytime asthma symptoms were reported by 56% of the respondents, and 51 % reported being awakened by their asthma at night. More than half of those surveyed had been hospitalized, attended a hospital emergency service or made unscheduled emergency visits to other healthcare facilities for asthma during the previous year. Patient perception of asthma control did not match symptom severity, even in patients with severe persistent asthma, 44.7% of whom regarded their disease as being well or completely controlled. Only 2.4% (2.3% adults and 2.6% children) met all criteria for asthma control. Although 37% reported treatment with prescription medications, only 6% were using inhaled corticosteroids. Most adults (79%) and children (68%) in this survey reported that asthma symptoms limited their activities. Absence from school and work was reported by 58% of the children and 31% of adults, respectively. Conclusions. Asthma control in Latin America falls short of goals in international guidelines, and in many aspects asthma care and control in Latin America suffer from the same shortcomings as in other areas of the world.Acceso abierto
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The International Study of Wheezing in Infants: questionnaire validation.(Karger AG, Basel, 2007-01-01)Background: There are no internationally validated questionnaires to investigate the prevalence of infant wheezing. This study was undertaken to validate a questionnaire for the International Study on the Prevalence of Wheezing in Infants (Estudio Internacional de Sibilancias en Lactantes, EISL). Material and Methods: Construct and criterion validity were tested for the question 'Has your baby had wheezing or whistling in the chest during his/her first 12 months of life?'. Construct validity (i.e. the ability of parents and doctors to refer to the same symptoms with the same words) was tested in a sample of 50 wheezing and 50 non-wheezy infants 12-15 months of age in each of 10 centres from 6 different Spanish- or Portuguese-speaking countries. Criterion validity (i.e. the ability of parents to correctly detect the symptom in the general population) was evaluated in 2 samples (Santiago, Chile and Cartagena, Spain) of 50 wheezing and 50 non-wheezing infants (according to parents) of the same age, randomly selected from the general population, who were later blindly diagnosed by a paediatric pulmonologist. Results: Construct validity was very high (κ test: 0.98-1) in all centres. According to Youden's index, criterion validity was good both in Cartagena (75.5%) and in Santiago (67.0%). Adding questions about asthma medication did not improve diagnosis accuracy. Conclusions: The EISL questionnaire significantly distinguished wheezy infants from healthy ones. This questionnaire has a strong validity and can be employed in large international multicentre studies on wheezing during infancy.Acceso restringido temporalmente
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Global variations in prevalence of eczema symptoms in children from ISAAC Phase Three.(Mosby Inc., 2009-12-01)Background: In 1999, The International Study of Asthma and Allergies in Childhood (ISAAC) Phase One reported the prevalence of eczema symptoms in 715,033 children from 154 centers in 56 countries by using standardized epidemiologic tools. Objective: To update the world map of eczema prevalence after 5 to 10 years (ISAAC Phase Three) and include additional data from over 100 new centers. Methods: Cross-sectional surveys using the ISAAC questionnaire on eczema symptoms were completed by adolescents 13 to 14 years old and by parents of children 6 to 7 years old. Current eczema was defined as an itchy flexural rash in the past 12 months and was considered severe eczema if associated with 1 or more nights per week of sleep disturbance. Results: For the age group 6 to 7 years, data on 385,853 participants from 143 centers in 60 countries showed that the prevalence of current eczema ranged from 0.9% in India to 22.5% in Ecuador, with new data showing high values in Asia and Latin America. For the age group 13 to 14 years, data on 663,256 participants from 230 centers in 96 countries showed prevalence values ranging from 0.2% in China to 24.6% in Columbia with the highest values in Africa and Latin America. Current eczema was lower for boys than girls (odds ratio, 0.94 and 0.72 at ages 6 to 7 years and 13 to 14 years, respectively). Conclusion:ISAAC Phase Three provides comprehensive global data on the prevalence of eczema symptoms that is essential for public health planning. New data reveal that eczema is a disease of developing as well as developed countries.Acceso restringido temporalmente
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The impact of the method of consent on response rates in the ISAAC time trends study.(nternational Union against Tubercul. and Lung Dis., 2010-08-01)BACKGROUND: Centres in Phases I and III of the International Study of Asthma and Allergies in Childhood (ISAAC) programme used the method of consent (passive or active) required by local ethics committees. METHODS: Retrospectively, relationships between achieved response rates and method of consent for 13-14 and 6-7-year-olds (adolescents and children, respectively), were examined between phases and between English and non-English language centres. RESULTS: Information was obtained for 113 of 115 centres for adolescents and 72/72 centres for children. Both age groups: most centres using passive consent achieved high response rates (>80% adolescents and >70% children). English language centres using active consent showed a larger decrease in response rate. Adolescents: seven centres changed from passive consent in Phase I to active consent in Phase III (median decrease of 13%), with five centres showing lower response rates (as low as 34%). Children: no centre changed consent method between phases. Centres using active consent had lower median response rates (lowest response rate 45%). CONCLUSION: The requirement for active consent for population school-based questionnaire studies can impact negatively on response rates, particularly English language centres, thus adversely affecting the validity of the data. Ethics committees need to consider this issue carefully.Acceso abierto
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Asthma and Rhinitis in South America: How Different They are From Other Parts of the World.(Korean Academy of Asthma, Allergy and Clinical Immunology and the Korean Academy of Pediatric Allergy and Respiratory Disease, 2012-03-01)Asthma and rhinitis epidemiology has wide variations around the world. The aim of this review was verify the prevalence of asthma and rhinitis in South America and report differences from other regions of the world. We reviewed studies with International Study of Asthma and Allergies in Childhood (ISAAC) methodology in South America, Phases I and III. In South America the ISAAC Phase I ranked four countries among top ten in prevalence of asthma and three countries among top ten in prevalence of rhinoconjunctivitis. ISAAC Phase III showed little changes in asthma and rhinitis prevalence in South American countries. The prevalence increases of asthma and rhinitis in South American centers indicate that the burden of both is continuing to rise, but the differences in prevalence are lessening.Acceso abierto
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Body mass index and vigorous physical activity in children and adolescents: an international cross-sectional study.(Blackwell Publishing Ltd, 2017-08-01)Aim: To examine the relationship between reported vigorous physical activity (VPA) and body mass index (BMI) in children (6–7 years) and adolescents (13–14 years). Methods: In the International Study of Asthma and Allergies in Childhood Phase Three, 75 895 children's parents and 199 502 adolescents answered questions relating to VPA, height and weight. The association between VPA and BMI was analysed using general linear models, adjusting for country gross national index. Results: Compared to children who undertook no VPA, those in the infrequent group (once or twice per week) and those in the frequent group (three or more times per week) had mean (95% CI) BMI values 0.07 kg/m 2 (0.03–0.11) and 0.09 kg/m 2 (0.03–0.15) greater, respectively (p = 0.001). Compared to adolescents reporting no VPA, those in the infrequent group had a BMI 0.19 kg/m 2 (0.15–0.23) greater while those in the frequent group had a BMI 0.01 kg/m 2 (−0.03–0.05) greater (p < 0.0001). Conclusion: Reported VPA is not associated with lower BMI among children and adolescents. Investigation of VPA and BMI may be best undertaken in conjunction with other variables in the energy expenditure equation. A focus on VPA alone may be an inefficient way to manage BMI.Acceso restringido temporalmente
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Association between Frequency of Consumption of Fruit, Vegetables, Nuts and Pulses and BMI: Analyses of the International Study of Asthma and Allergies in Childhood (ISAAC).(MDPI AG, 2018-03-07)Diets which emphasize intakes of plant-based foods are recommended to reduce disease risk and for promoting healthy weight. The aim of this study was to examine the association between fruit, vegetables, pulses and nut intake and body mass index (BMI) across countries in adolescents (13-14 years) and children (6-7 years). Data from the International Study of Asthma and Allergies in Childhood; 77,243 children's parents and 201,871 adolescents was used to examine the association between dietary intake (Food Frequency Questionnaire) and BMI using general linear models, adjusting for country gross national index. Adolescents who consumed fruit, vegetables, pulses and nuts three or more times a week had a lower BMI than the never or occasional group; eating nuts three or more times a week, was associated with a BMI value of 0.274 kg/m² lower than the never group (p < 0.001). Compared to children who never or occasionally reported eating vegetables, those reporting that they ate vegetables three or more times per week had a lower BMI of -0.079 kg/m². In this large global study, an inverse association was observed between BMI and the reported increasing intake of vegetables in 6-7 years old and fruit, vegetables, pulses and nuts in adolescents. This study supports current dietary recommendations which emphasize the consumption of vegetables, nut and pulses, although the effect sizes were small.Acceso abierto
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Are environmental risk factors for current wheeze in the International Study of Asthma and Allergies in Childhood (ISAAC) phase three due to reverse causation?(Blackwell Publishing Ltd, 2019-04-01)Background: Phase Three of the International Study of Asthma and Allergies in Childhood (ISAAC) measured the global prevalence of symptoms of asthma in children. We undertook comprehensive analyses addressing risk factors for asthma symptoms in combination, at both the individual and the school level, to explore the potential role of reverse causation due to selective avoidance or confounding by indication. Objective: To explore the role of reverse causation in risk factors of asthma symptoms. Methods: We compared two sets of multilevel logistic regression analyses, using (a) individual level exposure data and (b) school level average exposure (ie prevalence), in two different age groups. In individual level analyses, reverse causation is a possible concern if individual level exposure statuses were changed as a result of asthma symptoms or diagnosis. School level analyses may suffer from ecologic confounding, but reverse causation is less of a concern because individual changes in exposure status as a result of asthma symptoms would only have a small effect on overall school exposure levels. Results: There were 131 924 children aged 6-7 years (2428 schools, 25 countries) with complete exposure, outcome and confounder data. The strongest associations in individual level analyses (fully adjusted) were for current paracetamol use (odds ratio = 2.06; 95% confidence interval 1.97-2.16), early life antibiotic use (1.65; 1.58-1.73) and open fire cooking (1.44; 1.26-1.65). In school level analyses, these risk factors again showed increased risks. There were 238 586 adolescents aged 13-14 years (2072 schools, 42 countries) with complete exposure, outcome and confounder data. The strongest associations in individual level analyses (fully adjusted) were for current paracetamol use (1.80; 1.75-1.86), cooking on an open fire (1.32; 1.22-1.43) and maternal tobacco use (1.23; 1.18-1.27). In school level analyses, these risk factors again showed increased risks. Conclusions & clinical relevance: These analyses strengthen the potentially causal interpretation of previously reported individual level findings, by providing evidence against reverse causation.Acceso abierto
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Are Environmental Factors for Atopic Eczema in ISAAC Phase Three due to Reverse Causation?(Elsevier B.V., 2019-05-01)Some previously described environmental associations for atopic eczema may be due to reverse causation. We explored the role of reverse causation by comparing individual- and school-level results for multiple atopic eczema risk factors. The International Study of Asthma and Allergies in Childhood (i.e, ISAAC) Phase Three surveyed children in schools (the sampling unit) regarding atopic eczema symptoms and potential risk factors. We assessed the effect of these risk factors on atopic eczema symptoms using mixed-effect logistic regression models, first with individual-level exposure data and second with school-level exposure prevalence. Overall, 546,348 children from 53 countries were included. At ages 6–7 years, the strongest individual-level associations were with current paracetamol use (odds ratio [OR] = 1.45, 95% confidence interval [CI] = 1.37–1.54), which persisted at school-level (OR = 1.55, 95% CI = 1.10–2.21), early-life antibiotics (OR = 1.41, 95% CI = 1.34–1.48), and early-life paracetamol use (OR = 1.28, 95% CI = 1.21–1.36), with the former persisting at the school level, whereas the latter was no longer observed (OR = 1.35, 95% CI = 1.00–1.82 and OR = 0.94, 95% CI = 0.69–1.28, respectively). At ages 13–14 years, the strongest associations at the individual level were with current paracetamol use (OR = 1.57, 95% CI = 1.51–1.63) and open-fire cooking (OR = 1.46, 95% CI = 1.33–1.62); both were stronger at the school level (OR = 2.57, 95% CI = 1.84–3.59 and OR = 2.38, 95% CI = 1.52–3.73, respectively). Association with exposure to heavy traffic (OR = 1.31, 95% CI = 1.27–1.36) also persisted at the school level (OR = 1.40, 95% CI = 1.07–1.82). Most individual- and school-level effects were consistent, tending to exclude reverse causation.Acceso abierto
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Maternal post-natal tobacco use and current parental tobacco use is associated with higher body mass index in children and adolescents: an international cross-sectional study.(BioMed Central Ltd., 2015-12-24)Background: We investigated whether maternal smoking in the first year of life or any current parental smoking is associated with childhood or adolescent body mass index (BMI). Methods: Secondary analysis of data from a multi-centre, multi-country, cross-sectional study (ISAAC Phase Three). Parents/guardians of children aged 6-7 years completed questionnaires about their children's current height and weight, whether their mother smoked in the first year of the child's life and current smoking habits of both parents. Adolescents aged 13-14 years completed questionnaires about their height, weight and current parental smoking habits. A general linear mixed model was used to determine the association between BMI and parental smoking. Results: 77,192 children (18 countries) and 194 727 adolescents (35 countries) were included. The BMI of children exposed to maternal smoking during their first year of life was 0.11 kg/m 2 greater than those who were not (P = 0.0033). The BMI of children of currently smoking parents was greater than those with non-smoking parents (maternal smoking: +0.08 kg/m 2 (P = 0.0131), paternal smoking: +0.10 kg/m 2 (P < 0.0001)). The BMI of female adolescents exposed to maternal or paternal smoking was 0.23 kg/m 2 and 0.09 kg/m 2 greater respectively than those who were not exposed (P < 0.0001). The BMI of male adolescents was greater with maternal smoking exposure, but not paternal smoking (0.19 kg/m 2 , P < 0.0001 and 0.03 kg/m 2 , P = 0.14 respectively). Conclusion: Parental smoking is associated with higher BMI values in children and adolescents. Whether this is due to a direct effect of parental smoking or to confounding cannot be established from this observational study.Acceso abierto
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Over 675,000 lay people trained in cardiopulmonary resuscitation worldwide - The "World Restart a Heart (WRAH)" initiative 2018.(Elsevier Ireland Ltd, 2019-05-01)Cartas al editorAcceso restringido temporalmente
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Programa de mindfulness para la reducción de la ansiedad precompetitiva en deportistas de artes marciales(Federación Española de Asociaciones Docentes de Educación Física, 2019-01)El objetivo del presente estudio fue examinar el efecto de un programa de intervención con componente mindfulness para la reducción de la ansiedad precompetitiva, el cual fue adaptado de programas que han demostrado su eficacia. La intervención estuvo compuesta por 12 sesiones de 1 hora de duración. Participaron en el estudio 33 deportistas de artes marciales (M = 18.97 años, DE = 1.64; 69.7% hombres). La ansiedad precompetitiva fue evaluada con la versión revisada del Inventario de Ansiedad Estado Competitiva -2 (CSAI-2R; Cox, Martens y Rusell, 2003), antes y después del periodo de la intervención. De acuerdo al grado de participación en la intervención, la muestra fue dividida en 2 grupos: Grupo Control (GC, n = 16) y Grupo Experimental (GE, n = 17). Los resultados evidenciaron diferencias significativas con tamaños del efecto grandes en la medida post test del GE, revelando una disminución en los niveles de ansiedad somática y cognitiva, y un aumento en los niveles de autoconfianza. Mientras, en el GC, no se obtuvo diferencias significativas y los tamaños del efecto fueron irrelevantesAcceso abierto
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Postbuckling Analysis of Functionally Graded Beams(Institute of Physics Publishing, 2019-02-26)This paper studies the geometrically non-linear bending behavior of functionally graded beams subjected to buckling loads using the finite element method. The computational model is based on an improved first-order shear deformation theory for beams with five independent variables. The abstract finite element formulation is derived by means of the principle of virtual work. High-order nodal-spectral interpolation functions were utilized to approximate the field variables which minimizes the locking problem. The incremental/iterative solution technique of Newton's type is implemented to solve the nonlinear equations. The model is verified with benchmark problems available in the literature. The objective is to investigate the effect of volume fraction variation in the response of functionally graded beams made of ceramics and metals. As expected, the results show that transverse deflections vary significantly depending on the ceramic and metal combination.
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Relationship between stunting in children 6 to 36 months of age and maternal employment status in Peru: A sub-analysis of the Peruvian Demographic and Health Survey(Public Library of Science, 2019-04)Objectives This study aimed to determine the relationship between stunting in children 6 to 36 months old and maternal employment status in Peru. Methods A secondary data analysis was conducted using information from the Demographic and Health Survey (DHS) in Peru. We used a representative sample of 4637 mother-child binomials to determine the association between stunting in children 6 to 36 months of age and the employment status of their mothers. Results The prevalence of stunting among children was 15.9% (95% CI: 13.9–16.7). The prevalence of working mothers was 63.7%. No association was found between maternal employment status and the presence of stunting in children [prevalence ratio (PR) = 1.04; 95% confidence interval (95% CI): 0.9 to 1.2; p = 0.627). However, on multivariate analysis we found that the prevalence of stunting was significantly higher among children of mothers performing unpaid work (12.4%) (PR = 1.38; 95% CI: 1.2–1.6; p < 0.001) compared with those of paid working mothers. Conclusion No significant association was found between maternal employment status and the presence of stunting in children 6 to 36 months of age. However, children of mothers doing unpaid work are at higher risk of stunting. These findings support the implementation of educational programs and labour policies to reduce the prevalence of stunting among children. © 2019 Chávez-Zárate et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Acceso abierto
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Comments on the Study "The Sensitivity, Specificity and Accuracy of Warning Signs in Predicting Severe Dengue, the Severe Dengue Prevalence and Its Associated Factors"(NLM (Medline), 2019-03-14)Comments were made on the article “The Sensitivity, Specificity and Accuracy of Warning Signs in Predicting Severe Dengue, the Severe Dengue Prevalence and Its Associated Factors” found in the journal “International Journal of Environmental Research and Public Health” based on the CASP Checklist’s guide for the assessment of diagnostic tests.Acceso abierto
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Organically vs conventionally-grown dark and white chia seeds (salvia hispanica L.): Fatty acid composition, antioxidant activity and techno-functional properties(CSIC Consejo Superior de Investigaciones Cientificas, 2019-04-02)The effects of organic and conventional crop systems on chemical composition, antioxidant activity and functional properties were evaluated in white and dark chia (Salvia hispanica L.) seeds. The organic system reduced the total protein content, and increased the total carbohydrates but did not change polyunsaturated fatty acids, total phenolic or flavonoids. Organic white chia seeds showed the best techno-functional properties. The antioxidant capacity of chia extracts varied in relation to the chemical complexity and differential rate kinetics of different assays. Extractable total phenolic acids and antioxidant capacity were better in organic white chia seeds. In this first approach, we have demonstrated that the organic white chia seed has a better total antioxidant capacity measured by direct quencher approaches than its conventionally-grown counterpart. To summarize, we conclude that the organic white chia seed could be a dietary source of antioxidants with a potential to promote health benefits in systemic functions and/or microbiota and the use of its techno-functional properties for the food industry.Acceso abierto
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Nosocomial infections increase the length of hospital stay(Elsevier Ltd, 2019-04-30)Cartas al editorAcceso restringido temporalmente
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Social license to operate in the mining industry: the case of Peru(Taylor and Francis Ltd., 2019-03-15)Mining is an important industry in Peru, but local communities where mining takes place do not perceive its benefits. Mining corporations need to achieve legitimacy within these communities. The main objective of this study is to identify the factors that determine the provision of social licenses to operate in Peru’s mining regions. We conducted this research using a case study of two Peruvian mining companies. Our study concludes with the identification of four essential factors needed to achieve a social license to operate within these communities: a deep understanding of the socioeconomic environment, a strong commitment to the community, an active presence of Government, and effective communication between the actors involved in mining activities. The combination of these elements can result in improved trust levels between companies and society, enabling all agents to recognize the costs and benefits resulting from mining.Acceso abierto
