[Declaration of allergens on food labels: overview of Latin AmericaDeclaração de alergênicos na rotulagem de alimentos: panorama da América Latina]. / Declaración de alergenos en el etiquetado de alimentos: panorama latinoamericano.

Objective: Identify countries that have legislation on mandatory declarations of food allergens, irradiated foods, and transgenic foods on the nutritional labels of packaged foods. Methods: Exploratory study reviewing the health regulations and technical standards for foods in Latin American countries in order to gather information on declarations of allergens, trace allergens, irradiated foods, and transgenic foods. The information search was carried out through the countries' government web pages. Presentation of the results is descriptive and narrative. Results: Of the 19 countries reviewed, 89% require a declaration of allergens on their nutrition labeling, 76% have legislation that explicitly require a statement on trace allergens, and 82% follow Codex Alimentarius recommendations with some modifications of food categories. Conclusions: Three pending challenges in the Region are: requiring statements on allergens as a food safety measure; making progress toward improved labeling of trace allergens; and ensuring universal availability of epinephrine.

Objetivo: Identificar os países que têm legislação relacionada à declaração obrigatória de alimentos alergênicos, irradiados e transgênicos na rotulagem nutricional de alimentos embalados. Métodos: Estudo exploratório com revisão dos regulamentos sanitários ou normas técnicas de alimentos dos países da América Latina, a fim de coletar informações sobre a declaração de alimentos alergênicos, traços de alergênicos, alimentos irradiados e transgênicos na rotulagem nutricional. A busca de informações foi realizada por meio dos sites governamentais dos países. Os resultados são apresentados de forma descritiva e narrativa. Resultados: Dos 19 países analisados, 89% declaram alergênicos na rotulagem nutricional, 76% incorporam explicitamente a declaração de traços na legislação e 82% seguem as recomendações do Codex Alimentarius, com algumas modificações nas categorias de alimentos. Conclusões: Entre os desafios pendentes na Região estão a implementação da declaração de alergênicos como medida de segurança alimentar e a melhoria da rotulagem de traços de alergênicos e da disponibilidade universal de epinefrina.

Declaración de alergenos en el etiquetado de alimentos: panorama latinoamericano / Declaration of allergens on food labels: overview of Latin America / Declaração de alergênicos na rotulagem de alimentos: panorama da América Latina

RESUMEN Objetivo. Identificar los países que tienen legislación relacionada con la declaración obligatoria de alergenos alimentarios, alimentos irradiados y transgénicos en el etiquetado nutricional de alimentos envasados. Métodos. Estudio exploratorio en el cual se revisaron los reglamentos sanitarios o normas técnicas de los alimentos de los países de América Latina con el fin de recopilar información sobre la declaración de alergenos, trazas de alergenos, alimentos irradiados y transgénicos. La búsqueda de la información se realizó a través de páginas gubernamentales de los países. Los resultados se presentan de manera descriptiva y narrativa. Resultados. De los 19 países revisados, 89% declara alergenos en su etiquetado nutricional, 76% incorpora la declaración de trazas en su legislación de manera explícita y 82% sigue las recomendaciones del Codex Alimentarius con algunas modificaciones en las categorías de alimentos. Conclusiones. La declaración de alergenos como medida de seguridad alimentaria, así como avanzar en mejorar la rotulación de trazas de alergenos y la disponibilidad universal de epinefrina son los desafíos pendientes de la Región.

ABSTRACT Objective. Identify countries that have legislation on mandatory declarations of food allergens, irradiated foods, and transgenic foods on the nutritional labels of packaged foods. Methods. Exploratory study reviewing the health regulations and technical standards for foods in Latin American countries in order to gather information on declarations of allergens, trace allergens, irradiated foods, and transgenic foods. The information search was carried out through the countries' government web pages. Presentation of the results is descriptive and narrative. Results. Of the 19 countries reviewed, 89% require a declaration of allergens on their nutrition labeling, 76% have legislation that explicitly require a statement on trace allergens, and 82% follow Codex Alimentarius recommendations with some modifications of food categories. Conclusions. Three pending challenges in the Region are: requiring statements on allergens as a food safety measure; making progress toward improved labeling of trace allergens; and ensuring universal availability of epinephrine.

RESUMO Objetivo. Identificar os países que têm legislação relacionada à declaração obrigatória de alimentos alergênicos, irradiados e transgênicos na rotulagem nutricional de alimentos embalados. Métodos. Estudo exploratório com revisão dos regulamentos sanitários ou normas técnicas de alimentos dos países da América Latina, a fim de coletar informações sobre a declaração de alimentos alergênicos, traços de alergênicos, alimentos irradiados e transgênicos na rotulagem nutricional. A busca de informações foi realizada por meio dos sites governamentais dos países. Os resultados são apresentados de forma descritiva e narrativa. Resultados. Dos 19 países analisados, 89% declaram alergênicos na rotulagem nutricional, 76% incorporam explicitamente a declaração de traços na legislação e 82% seguem as recomendações do Codex Alimentarius, com algumas modificações nas categorias de alimentos. Conclusões. Entre os desafios pendentes na Região estão a implementação da declaração de alergênicos como medida de segurança alimentar e a melhoria da rotulagem de traços de alergênicos e da disponibilidade universal de epinefrina.

[Agreement between self-perception of body image and nutritional status in a Chilean population]. / Concordancia entre la autopercepción de la imagen corporal y el estado nutricional en la población chilena.

Introduction: Introduction: obesity is a public health problem. No significant decrease in the prevalence of obesity has been globally observed. A better understanding of the factors that can influence obesity is necessary, one of them being self-perception of body weight. Objective: to determine the agreement between self-perception of body image and nutritional status in a Chilean population. Methods: an analytical cross-sectional study was carried out based on the Chilean National Health Survey 2016-2017. Nutritional status was measured by body mass index (BMI) and self-perceived body weight. Agreement was estimated by the kappa index and weighted kappa index. These indices were specified according to sociodemographic variable. Results: the total number of participants was 5483, with 51 % (95 % CI: 48.7-53.5) corresponding to women. Mean age was 43.2 years (95 % CI: 42.4-44.0). The kappa index showed a low concordance (kappa, 0.194; 95 % CI: 0.177 to 0.211) among women, people from rural areas, and subjects with fewer years of education. The global weighted kappa was 0.325; 95 % CI (0.168-0.482). Conclusions: underestimation of nutritional status can lead to negation of the problem generated by excess body weight. Recognizing nutritional status is a critical stage to initiate behavior changes and start having healthy eating habits. More than half of Chileans present distortion of body image, prevailing underestimation of body weight.

Introducción: Introducción: la obesidad es un problema de salud pública. No se ha observado una disminución significativa de la prevalencia de la obesidad a nivel mundial. Es necesaria una mejor comprensión de los factores que pueden influir en la obesidad y uno de ellos es la autopercepción del peso corporal. Objetivo: determinar la concordancia entre la autopercepción de la imagen corporal y el estado nutricional real en la población chilena de 15 y más años. Métodos: se realizó un estudio transversal analítico basado en la Encuesta Nacional de Salud de Chile 2016-2017. Se midió el estado nutricional junto con la autopercepción del peso corporal. Se estimó el índice de concordancia kappa y el kappa ponderado. Estos índices se especificaron según la variable sociodemográfica. Resultados: un 51 % (IC 95 %: 48,7-53,5) corresponden a mujeres. La edad media fue de 43,2 años (IC 95 %: 42,4-44,0). El índice kappa mostró una baja concordancia (kappa: 0,194; IC 95 %: 0,177 a 0,211), siendo inferior en las mujeres, las personas de área rural y las de menos años de educación. El kappa ponderado global fue de 0,325; IC 95 % (0,168-0,482). Conclusiones: la subestimación del estado nutricional favorece la negación del problema que genera el exceso de peso corporal. Reconocer el estado nutricional que se tiene es una etapa crítica para iniciar un cambio de comportamiento; por lo tanto, evaluar incorrectamente el peso corporal impide iniciar hábitos de alimentación saludable. Más de la mitad de los chilenos presentan distorsión de la imagen corporal, prevaleciendo la subestimación del peso corporal.

[Most frequent themes in Editorials of Vertex journal (1990-2019) analyzed by graph theory]. / Temáticas más frecuentes en los Editoriales de Vertex Revista Argentina de Psiquiatría (1990-2019) analizadas mediante grafos.

BACKGROUND AND OBJECTIVE: The analysis of Editorials is a little explored topic, which can facilitate the understanding of historical processes and changes in Psychiatry. In the case of de Vertex Revista Argentina de Psiquiatría, the Editorials were written by the same person for 30 years. The most frequently used thematic areas were studied, using graph theory, to characterize the orientation of the editorial lines. This analysis was complemented with semi-structured interviews with the Editor. METHOD: The most significant words of the Editorials were determined and analyzed through a system of graph theory, divided by lustrums. RESULTS: The thematic areas of the journal were concentrated in five main themes that were reiterated in each lustrum: Ethics, History, Mental Health, Psychiatry and, in the last two, Politics. The editorials showed different degrees of complexity, being those of the first 15 years simpler than the last ones. The recurrence tendencies of the thematic areas of the Editorials were related to expressions arising from the interviews. CONCLUSION: The analysis with graph theory has made it possible to visualize aspects of the de Vertex Revista Argentina de Psiquiatría Editorials, their degree of thematic complexity and how some themes were reiterated over and over again throughout the 30 years of the journal.

Experience with ustekinumab in reservoir Crohn's disease.

Crohn's disease of the reservoir is a pathology of difficult diagnosis and complex approach due to the scarce documented evidence on it. Recently, studies have been published on the treatment strategies available for this entity. Based on the above, we have analyzed the experience of our center in the treatment of reservoir Crohn's disease with one of the new biologic agents, ustekinumab.

Medidas implementadas en Chile para garantizar el acceso a los alimentos durante pandemia COVID-19

RESUMEN Objetivo: Describir las medidas gubernamentales y no gubernamentales implementadas en Chile para garantizar las dimensiones de acceso y disponibilidad de la seguridad alimentaria durante la pandemia por COVID-19. Método: Se realizó un estudio cualitativo narrativo. La búsqueda de la información se realizó a través del Ministerio de Salud, Ministerio de Desarrollo Social y Familia (MIDESO), Ministerio de Agricultura y Junta Nacional de Auxilio Escolar y Becas JUNAEB además de reuniones con representantes de JUNAEB y MIDESO. Resultados: Las medidas gubernamentales se centraron en apoyar a las familias que vieron disminuido su ingreso económico y en menor medida, se enfocaron en mejorar la disponibilidad de alimentos. Las medidas no gubernamentales fueron principalmente entrega de alimentos y productos de higiene por la empresa privada. Conclusión: Es necesario evaluar el impacto de las medidas implementadas y monitorizar el efecto de la pandemia en la población con el fin de mejorar las medidas existentes o implementar otras nuevas.

ABSTRACT Objective: To describe governmental and non-governmental measures implemented in Chile to guarantee access and availability of food security during the COVID-19 pandemic. Methods: Qualitative narrative study. The information was sought in the Ministry of Health, Ministry of Social Development and Family (MIDESO), Ministry of Agriculture and the National Board of Scholarships for School Aid (JUNAEB), as well as meetings with representatives of JUNAEB and MIDESO. Results: Government measures focused on supporting families that saw their income decreased, to a lesser extent, they focused on improving food availability. The non-governmental measures were mainly the delivery of food and hygiene products by private companies. Conclusion: It is necessary to assess the impact and monitor the effects of programs implemented related to food security during the pandemic to improve existing ones or implement new ones.

[Maternal leave extension effect on breastfeeding according to poverty, Chile 2008-2018]. / Efecto de la extensión de licencia maternal en la lactancia materna según pobreza en Chile 2008-2018.

INTRODUCTION: In Chile in 2011, the postnatal leave was extended from 12 to 24 weeks. OBJECTIVE: To determine the effects of the extension of maternity leave on the prevalence of breastfeeding in Chile according to poverty groups. METHODS: Ecological study on the annual prevalence of exclusive breastfeeding at 1st month (EBF1m) and 6th month (EBF6m), and supplemented at 12th month (BF12m) in the public health system between 2008 and 2018, based on the monthly statistical records of primary care. The prevalence was calculated nationally and by region groups according to the poverty level reported by the National Socioeconomic Characterization Survey (CASEN). The variation in the time trend was determined through segmented Poisson regression models (joinpoint), estimating the Annual Percentage Change (APC). RESULTS: Nationally, since 2011, the prevalence of EBF6m and BF12m increased annually by 5.9% and 4.2%, reaching 58.9% and 40.2% in 2018, respectively. This pattern is repeated in the different regional poverty groups, showing a higher prevalence in the poorest group, reaching 61.7% at EBF6m and 51.6% at BF12m in 2018. The EBF1m decreased annually by 1.7% between 2008 and 2014 and then remained without changes, reaching 74.7% in 2018. CONCLUSIONS: The EBF6m prevalence increased significantly since 2011 due to the extension of the maternity leave. This effect occurs in all regional groups of poverty, narrowing the differen ces in prevalence.

Características y contenido de los programas de Magíster en Salud Pública en Chile / Features and contents of master programs in public health in Chile

Background: In Chile, public health training grew both in enrollment and in the number of universities offering programs on the subject. Aim: To compare the academic characteristics and the contents of the master's programs in public health offered by Chilean universities. Material and Methods: A search of all master's programs that include the word "public health " in their title was made, excluding those that did not declare current students in 2020. The academic characteristics and content of each program were compiled according to the information declared by each university. The contents were grouped according to the list of core competencies for the public health professional of the Association of Schools of Public Health in the European Region (ASPHER). Results: Eleven programs were included, most of them are carried out in face-to-face modality. The academic load is expressed in Transferable Credit System credits (62-71), credits (87-125) or teaching hours (1252-2048). All programs declare to have a graduation activity, with a heterogeneous academic load. All programs have basic subjects in epidemiology and more than 60% include introductory topics in public health, research methodology, and health services management. No program declares demography or food safety as compulsory subjects. Conclusions: There is heterogeneity in the academic load and the contents between the programs. It is necessary to establish common criteria in the training of future public health professionals, at least in the compulsory subjects and the minimum academic load.

[Features and contents of master programs in public health in Chile]. / Características y contenido de los programas de Magíster en Salud Pública en Chile.

BACKGROUND: In Chile, public health training grew both in enrollment and in the number of universities offering programs on the subject. AIM: To compare the academic characteristics and the contents of the master's programs in public health offered by Chilean universities. MATERIAL AND METHODS: A search of all master's programs that include the word "public health " in their title was made, excluding those that did not declare current students in 2020. The academic characteristics and content of each program were compiled according to the information declared by each university. The contents were grouped according to the list of core competencies for the public health professional of the Association of Schools of Public Health in the European Region (ASPHER). RESULTS: Eleven programs were included, most of them are carried out in face-to-face modality. The academic load is expressed in Transferable Credit System credits (62-71), credits (87-125) or teaching hours (1252-2048). All programs declare to have a graduation activity, with a heterogeneous academic load. All programs have basic subjects in epidemiology and more than 60% include introductory topics in public health, research methodology, and health services management. No program declares demography or food safety as compulsory subjects. CONCLUSIONS: There is heterogeneity in the academic load and the contents between the programs. It is necessary to establish common criteria in the training of future public health professionals, at least in the compulsory subjects and the minimum academic load.

Involvement of the food industry in nutrition conferences in Latin America and the Caribbean.

OBJECTIVE: Identify and characterise the food industry's involvement in nutrition and dietetics national and regional events in Latin America and the Caribbean. DESIGN: Between February and April 2020, we conducted desk-based searches for nutrition and dietetics events held in the region between January 2018 and December 2019. Online freely accessible, publicly available information was collected on the involvement of the food industry through: sponsorship of events; sponsorship of sessions; speakers from the food industry; scholarships, fellowship, grants, awards and other prizes and; exhibition space/booths. SETTING: Nutrition and dietetics events in Latin America and the Caribbean. RESULTS: Thirty-one events held in twenty countries of the region had information publicly available online at the period of data collection. There was a lack of transparency on the involvement of industry actors in these events. When information was publicly available, we found that a total of ninety-two food industry actors sponsored 88 % of these events. CONCLUSIONS: There is a mostly unreported, but likely extensive, involvement of food industry actors in nutrition and dietetics events in Latin America and the Caribbean.

Revisión narrativa Modelos predictivos sobre la evolución de la pandemia por COVID-19 / Narrative review: predictive models on the evolution of COVID-19 pandemic

La modelización matemática se utiliza desde hace más de 100 años para evaluar el impacto de las estrategias de intervención de salud pública y sugerir el curso de acción óptimo en la lucha contra las enfermedades infecciosas emergentes. La aparición del nuevo virus SARS-CoV-2 plantea un gran desafío para los planificadores y decisores en salud, que deben movilizar recursos finitos, reorganizar los sistemas de atención y tomar decisiones en un contexto de gran incertidumbre. Para afrontar la pandemia por COVID-19, muchos sistemas de salud incorporan información provista por modelos predictivos. Esto insta a revisar la evolución de los distintos tipos de modelos existentes, sus características, limitaciones y vinculación con la toma de decisiones en Argentina y otros países. Con ese objetivo, se realizó una búsqueda bibliográfica sobre los modelos publicados acerca de la evolución de la pandemia. Se analizó el número de proyectos conexos presentados a becas del Ministerio de Ciencia, Tecnología e Innovación. Se identificaron, clasificaron y describieron distintos tipos de modelos, como determinísticos y estocásticos, distintos modelos compartimentados, y se describió la teoría del umbral y características principales de los modelos, como el número reproductivo básico (R0). Se analizó la importancia de los supuestos de cada modelo y el abordaje de la incertidumbre. Se discutieron sus principales limitaciones y su vinculación con la toma de decisiones en provincias y regiones.

Mathematical modeling has been used for over a hundred years to assess the impact of public health intervention strategies and suggest the optimal course of action in the fight against emerging infectious diseases. The appearance of the new SARS-CoV-2 virus poses a great challenge for health planners and decision-makers, who must allocate finite resources, reorganize care systems, and make decisions in a context of great uncertainty. Many health systems incorporate information provided by predictive models in their decision-making process to face the COVID-19 pandemic. This makes it necessary to review the evolution of the different types of existing models, their characteristics, limitations and link with decision-making in Argentina and other countries. In order to fulfill this objective, a bibliographic search was carried out on the published models about the evolution of the pandemic. The number of related projects submitted for scholarships from the Ministry of Science, Technology and Innovation was analyzed. Different types of published models were identified, classified and described, such as deterministic and stochastic, different compartmentalized models, threshold theory and main characteristics of the models were described as the basic reproductive number (R0). The importance of the assumptions of each model and the approach to uncertainty were analyzed. Its main limitations and its link with decision-making in provinces and regions were discussed.

Involvement of the food industry in nutrition conferences in Latin America and the Caribbean

Objective: Identify and characterise the food industry's involvement in nutrition and dietetics national and regional events in Latin America and the Caribbean. Design: Between February and April 2020, we conducted desk-based searches for nutrition and dietetics events held in the region between January 2018 and December 2019. Online freely accessible, publicly available information was collected on the involvement of the food industry through: sponsorship of events; sponsorship of sessions; speakers from the food industry; scholarships, fellowship, grants, awards and other prizes and; exhibition space/booths. Setting: Nutrition and dietetics events in Latin America and the Caribbean. Results: Thirty-one events held in twenty countries of the region had information publicly available online at the period of data collection. There was a lack of transparency on the involvement of industry actors in these events. When information was publicly available, we found that a total of ninety-two food industry actors sponsored 88 % of these events. Conclusions: There is a mostly unreported, but likely extensive, involvement of food industry actors in nutrition and dietetics events in Latin America and the Caribbean.(AU)

Is neck circumference an appropriate tool to predict cardiovascular risk in clinical practice? A cross-sectional study in Chilean population.

OBJECTIVES: Neck circumference has emerged as a predictor of obesity and metabolic syndrome, but its clinical usefulness for different groups of population is not clearly defined. The aim is to evaluate the predictive capacity of neck circumference in order to detect cardiovascular risks (CVRs) on the Chilean population and to compare it with waist circumference performance. DESIGN: Cross-sectional study. SETTING: General Chilean population. PARTICIPANTS: Data of 4607 adults aged 18 and over from the Chilean National Health Survey 2009-2010 were analysed. PRIMARY AND SECONDARY OUTCOME MEASURES: Anthropometrics measures included neck and waist circumference, height and weight. CVR was identified according to the Framingham tables adapted for the Chilean population. Receiver operating characteristics curves and logistic regression models were made to evaluate the performance of neck circumference to predict a moderate/high CVR, comparing it to waist circumference. RESULTS: Almost 10% of the sample had a moderate or high CVR. The probability of having a moderate/high cardiovascular risk increase with cervical obesity (OR 1.95, 95% CI 1.04 to 3.68) and central obesity (OR 4.5, 95% CI 2.47 to 8.22). The area under the curves were high for cervical obesity (AUC 81.4%, 95% CI 78.8% to 84.0%) and central obesity (AUC 82.2%, 95% CI 79.7% to 84.7%) and not statistically different (p=0.152). CONCLUSIONS: Neck obesity has a high capacity to predict moderate/high CVR in the Chilean population. Its good performance appears as an opportunity to use it in clinical practice when waist circumference measurement is difficult to measure and eventually replace the waist circumference measurement as the technique is easier.

Microbial nitrate removal efficiency in groundwater polluted from agricultural activities with hybrid cork treatment wetlands.

Agricultural practices have raised the level of nutrients reaching aquifers. In Europe, nitrate pollution is considered as one of the main threats for the quality of groundwater in agricultural areas. Treatment wetlands (TWs), also known as Constructed Wetlands, are used for groundwater treatment in areas with an important concentration of nitrogen compounds; total nitrogen removal depends on the type and operation scheme. Cork by-product from the industry has shown clear adsorbent properties to remove organic pollutants. The work is focused on the characterization of microbial communities involved in the nitrate­nitrogen removal process in groundwater polluted from agricultural activities. The experimental design allowed the comparison of nitrate removal efficiency depending on the filter media material, cork by-product or gravel, used in two hybrid TWs (a vertical flow cell followed by a horizontal subsurface flow cell), installed in areas close to two irrigated agricultural plots at the Lleida plain area (Spain). Both physicochemical and microbial results were consistent and confirm the nitrate removal efficiency using cork as a filter media. A significant (p = 0.0025) higher removal in Bellvís TW using cork compared with the Vilanova de la Barca gravel system was observed, achieving a removal rate from 80 to 99% compared to the 5-46%, respectively. Regarding the community composition of the two different TWs, microorganisms were mainly related to the phylum Proteobacteria, and included members found to be key players in the nitrogen cycle, such as ammonia and nitrite oxidizers, as well as denitrifiers. Also, the group Bacteroidetes turns to be another abundant phylum from our bacterial dataset, whose members are suggested to be strongly involved in denitrification processes. Some groups showed to prevail depending on the type of media (cork or gravel); Firmicutes and Delta and Epsilonproteobacteria had a significant higher abundance in the TW with cork, while Acidobacteria and Planctomyces were prevalent in gravel. Therefore, cork could be an alternative material used by treatment wetlands to minimize the impact in the environment caused by nitrogen pollution in groundwater bodies.

[Trend of exclusive breastfeeding in Chile before and after the parental postnatal law]. / Tendencia de la lactancia materna exclusiva en Chile antes y después de la implementación de la Ley postnatal parental.

INTRODUCTION: To describe the trend of exclusive breastfeeding (EBF) until sixth month of life in Chile before and after the implementation of the parental postnatal law in children treated in the public health system. MATERIAL AND METHOD: An observational and population-based study, using the EBF data up to the sixth month obtained from monthly statistical records (MSR), available at the Department of Information and Statistics on Health of children treated in the public health system. Prevalence and weighted prevalence were determined by region and country. Cumulative percentage variation (PV) and annual percentage variation (APV) of prevalence were analyzed using a linear regression model in the period before (2008-2011) and after (2011-2013) of the implementation of the law. RESULTS: The highest prevalence of EBF was observed in 2008 (49.1%) and 2009 (45.1%) and the lowest in 2011 (41.1%). The Antofagasta (33.6%) and Atacama Region (31.6%) had the lowest weighted prevalence of the period. A negative APV was observed in the period 2008-2011 and a positive APV in the period 2011-2013 in all regions and in the country, except for the B. O'Higgins Region. CONCLUSIONS: The enactment of the law that increases EBF until 24 weeks of life reverses the decreasing tendency previosly observed until the sixth month. This could encourage other governments to invest resources and efforts in early childhood by providing equity and health.

Tendencia de la lactancia materna exclusiva en Chile antes y después de la implementación de la Ley postnatal parental / Trend of exclusive breastfeeding in Chile before and after the parental postnatal law

INTRODUCCIÓN: Dada la implementación de la ley postnatal parental en niños atendidos en sistema público de salud, el objetivo de este estudio es describir la tendencia de la lactancia materna exclusiva (LME) al sexto de mes de vida en Chile antes y después de la implementación de la ley postnatal parental. MATERIAL Y MÉTODO: Estudio observacional de tipo poblacional, a partir de los datos de LME hasta el sexto mes obtenidos de los registros estadísticos mensuales (REM), disponibles en el Departamento de Información y Estadísticas en Salud de niños atendidos en el sistema público de salud. Se determinó la prevalencia y la prevalencia ponderada por región y país. Se analizó la variación porcentual acumulada (VP) y variación porcentual anual (VPA) de la prevalencia utilizando un modelo de regresión lineal en el período antes (2008-2011) y después (2011-2013) de la implementación de la ley. RESULTADOS: La mayor prevalencia de LME se observó en los años 2008 (49,1%) y 2009 (45,1%) y la menor en el año 2011(41,1%). Las regiones de Antofagasta (33,6%) y Atacama (31,6%) presentaron la menor prevalencia ponderada del período 2008-2013. Se observó una VPA negativa en el período 2008-2011 y una VPA positiva en el período 2011-2013 en todas las regiones y en el país, con excepción de la región del Gral. Libertador B. O'Higgins. CONCLUSIONES: La promulgación de la ley que aumenta el postnatal de 12 a 24 semanas revierte la tendencia decreciente de la LME al sexto mes. Esto podría incentivar a otros gobiernos para invertir recursos y esfuerzos en la primera infancia aportando a la equidad y la salud.

INTRODUCTION: To describe the trend of exclusive breastfeeding (EBF) until sixth month of life in Chile before and after the implementation of the parental postnatal law in children treated in the public health system. MATERIAL AND METHOD: An observational and population-based study, using the EBF data up to the sixth month obtained from monthly statistical records (MSR), available at the Department of Information and Statistics on Health of children treated in the public health system. Prevalence and weighted prevalence were determined by region and country. Cumulative percentage variation (PV) and annual percentage variation (APV) of prevalence were analyzed using a linear regression model in the period before (2008-2011) and after (2011-2013) of the implementation of the law. RESULTS: The highest prevalence of EBF was observed in 2008 (49.1%) and 2009 (45.1%) and the lowest in 2011 (41.1%). The Antofagasta (33.6%) and Atacama Region (31.6%) had the lowest weighted prevalence of the period. A negative APV was observed in the period 2008-2011 and a positive APV in the period 2011-2013 in all regions and in the country, except for the B. O'Higgins Region. CONCLUSIONS: The enactment of the law that increases EBF until 24 weeks of life reverses the decreasing tendency previosly observed until the sixth month. This could encourage other governments to invest resources and efforts in early childhood by providing equity and health.