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Resumen Introducción: La enfermedad respiratoria crónica determina alta morbimortalidad y frecuencia de comorbilidades cardiometabólicas. Evaluamos la asociación entre flujo espiratorio máximo (FEM) y algunas condiciones cardiometabólicas en adultos de una zona semirural, en la medición basal de la cohorte MAUCO (MAUle COhort). Material y Método: Estudio transversal (3.465 adultos, 40-74 años). Se midió el flujo espiratorio máximo (FEM) (mini-Wright, estándar ATS) utilizándose valores de Gregg y Nunn (FEM deteriorado ≤ 80% del teórico). Se obtuvo autorreporte/mediciones de hipertensión arterial (HTA), enfermedad cerebrovascular (ECV), infarto al miocardio (IAM), diabetes mellitus 2 (DM2), presión arterial, glicemia, colesterol, peso y talla. Actividad física y tabaquismo se evaluaron por encuesta, previa aprobación Ética. Se calcularon medidas de asociación, prevalencia y Odds Ratio (OR). Resultados: Muestra de 63,9% de mujeres edad media 55 (± 9) años, escolaridad media 9 (± 4) años. 84,7% tuvo exceso de peso, 81,5% inactividad física 29,4% fumadores actuales. Prevalencia de FEM bajo: 50,6% (IC 95% 48,9-52,3). El autorreporte fue: ACV 2,2% IAM 3,3, sospecha de hipertensión 24% y DM2 2,7%. Los OR crudos fueron significativos en mujeres que autorreportaron HTA, ECV, IAM y autorreporte/sospecha de DM2, y en hombres con autorreporte de ECV, sospecha de DM2 y autorreporte/sospecha de HTA. La asociación se mantuvo post-ajuste en mujeres para autorreporte de IAM y deterioro moderado (OR = 2,49) y severo del FEM (OR = 2,60) y en hombres para sospecha de DM2 y deterioro leve (OR = 5,24) y severo del FEM (OR = 6,19). Conclusiones: FEM resultó significativamente asociado con las enfermedades cardiometabólicas seleccionadas, con efecto sexo- específico para IAM (mujeres) y sospecha de DM2 (hombres). Se constata alta prevalencia de FEM alterado, y de enfermedades cardiometabólicas crónicas en la población estudiada. Introduction: Chronic respiratory diseases determine high morbimortality and cardiometabolic comorbidities. We evaluated the association between peak expiratory flow (PEF) and cardiometabolic conditions in adults in a semi-rural area, in the baseline of MAUCO cohort (MAUle COhort). Material and Method: Cross-sectional study (3,465 adults, 40-74 years). Peak expiratory flow (PEF) (mini-Wright, ATS standard) was measured (Gregg & Nunn; impaired PEF ≤ 80% predicted). Self-reported/measured hypertension (HT), cerebrovascular disease (CVD), myocardial infarction (AMI), diabetes mellitus 2 (DM2), blood pressure, glycemia, cholesterol, weight and height were obtained. Physical activity and smoking were surveyed, after Ethical approval. Association's measures, prevalence and Odds Ratio (OR) were calculated. Results: Sample of 63.9% of women, mean age 55 (± 9) years, schooling 9 (± 4) years. 84.7% had overweight, 81.5%physical inactivity 29.4% smokers. Low PEF: 50.6% (48.9-52.3). Self-reported was: CVD 2.2% AMI 3.3%, suspicion of hypertension 24% and DM2 2.7%. Crude OR`s were significant for women by self-reported hypertension, stroke, AMI and self-reported/suspicion DM2; in men for self-reported CVD, suspected DM2 and self-reported/suspected hypertension. The association remained post-adjusted in women self-reported AMI -moderate deterioration (OR = 2.49) and severe PEF (OR = 2.60) and in men suspected DM2 and mild (OR = 5.24) and severe deteriorated PEF (OR = 6.19). Conclusions: PEF was significantly associated with cardiometabolic diseases; sex- specific findings for AMI (women) and suspicion of DM2 (men). High prevalence of altered PEF and chronic cardiometabolic diseases were detected among the studied population.

Resumen Introducción: Las enfermedades respiratorias crónicas tienen alta prevalencia en países en desarrollo, en poblaciones rurales y deprivadas. El flujo espiratorio máximo (FEM) obtenido mediante espiración forzada tiene uso clínico y de investigación. Describimos valores de medición del FEM en la medición basal de un estudio de cohorte en curso (Cohorte del Maule-MAUCO). Material y Método: Diseño transversal en 3.465 adultos (40-74 años) con registros de FEM (ATS). (Flujómetro Mini-Wright), usando valores de Gregg y Nunn. Valores < 80% del predicho se consideraron disminuidos. Se obtuvo sexo, edad, nivel educacional, actividad física y tabaquismo; se calculó índice de masa corporal (IMC) usando mediciones antropométricas. Resultados: La muestra tuvo 63,9% de mujeres; edad media de 55 (± 9) años, escolaridad de 9 (± 4) años; sobrepeso y obesidad fueron 43,1% y 41,5%: 81,5% fueron inactivos y 29,4% fumadores actuales. El valor medio de FEM fue 330 (± 80) L/min (mujeres) y 460 (± 119) L/min (hombres): el FEM disminuido alcanzó el 50,6% ([48,9-52,3]) con diferencias según edad, educación, IMC y actividad física. Conclusiones: Se observó alta prevalencia de FEM disminuido con variaciones según sexo, edad, escolaridad, IMC e inactividad física. Como otros estudios latinoamericanos, los valores bajos también fueron altamente prevalentes, sugiriendo sobreestimación de valores predichos al usar valores de Gregg & Nunn. Estos resultados sugieren la conveniencia de estudiar factores ambientales locales. Introduction: Chronic respiratory (CRD) diseases show high prevalence in developing countries, rural and deprived populations. Peak expiratory flow rate (PEFR) is a functional measurement obtained through forced expiratory used for clinical and research purposes. We described PEFR in a rural setting in an ongoing cohort study (Maule Cohort-MAUCO). Material and Method: Cross-sectional design in 3,465 adults (40-74 years) with PEFR ATS standard records (Mini-Wright flowmeter) using Gregg and Nunn values. PEFR ≤ 80% predicted were considered decreased. Sex, age, educational level, physical activity and tobacco smoking were obtained. Body mass index (BMI) was calculated based on anthropometrical measurements. Main Results: Sample had 63.9% of women; mean age of 55 (± 9) years, schooling of 9 (± 4) years. Overweight and obesity were 43.1% and 41.5%. Physical inactivity was 81.5% and 29.4% were current smokers. PEFR mean value was 330 (± 80) L/min (women) and 460 (± 119) L/min (men): Decreased PEFR was 50.6% ([48.9-52.3]) with significant differences by age, schooling, BMI and physical activity. Conclusions: High prevalence of decreased PEFR was observed: PEFR showed variations according to sex, age, schooling, BMI and physical activity. As other Latin-American studies show, low values were also highly prevalent, suggesting that Gregg & Nunn overestimated PEFR values. These results suggests the convenience of studying local environmental factors.

Resumen Hay varias razones que respaldan la persistencia de altas cifras sobre consumo de tabaco en Chile. Entre los principales impulsores podemos destacar la fuerte influencia de la industria tabacalera y la debilidad de las Políticas Nacionales de Salud en la prevención, control y regulación del consume de tabaco a nivel poblacional. Uno de los principales resultados de salud derivados del consumo de tabaco es la dependencia de la nicotina, la principal barrera clínica y psicológica para que los fumadores dejen de fumar. Las actualizaciones de la legislación chilena aún muestran un efecto limitado a nivel de población adulta, según datos proporcionados por la Encuesta Nacional de Salud 2010, pero promisorios a nivel adolescentes según investigación local e internacional sobre población escolar (SENDA) y recientemente por la Encuesta Global de Jóvenes por el Tabaco (EMTJ 2016) La provision de acciones estructurales dirigidas a población general necesita ser complementada, con el fin de alentar y apoyar a los fumadores a dejar de fumar, considerando su rol fundamental en el control de la epidemia del tabaco, debido a la persistencia del consumo de tabaco en la población general. Consideramos que el abandono del tabaco debe ser un objetivo estratégico de prevención secundaria a considerar que permita aumentar el espectro de acciones propuestas por el Convenio Marco para el Control del Tabaco en Chile There are several reasons supporting the persistence of high figures on tobacco smoking in Chile. Among the main drivers we can highlight the strong influence of the tobacco industry and the weakness of National Health Policies on the prevention, control and regulation of tobacco consumption at the population level. One of the main health outcomes derived for smoking consumption is nicotine dependence, the main clinical and psychological barrier for smokers to quit tobacco smoking. Even the Chilean legislation updates still show limited effect at adult population level, according to data provided from National Health Survey 2010, but promissory information from local and international research on scholar population (SENDA) and recently by the Global Youth for Tobacco Survey (EMTJ 2016). The provision of structural actions directed to general populations need to be complemented for other, in order to encourage and support smokers to quit, considering their sensitive cornerstone role controlling the tobacco epidemics due the persistence of tobacco consumption in the general population. We consider that smoking cessation should be a strategic secondary prevention target to be considered that allow to increase the spectrum of actions proposed by the Framework Convention on Tobacco control in Chile

Background: In Chile, gastric cancer (GC) is a major cause of cancer related deaths. The current screening strategy consists of an upper gastrointestinal endoscopy (UGE) for people aged 40 years or more with epigastric pain. Aim: To evaluate the diagnostic coverage of the use of UGE for early detection of GC in Chile. Material and Methods: As part of the digestive module of the 2009-10 National Health Survey, 5293 adults over 15 years were asked about the presence of epigastric pain, possible upper gastrointestinal bleeding (PUGB), use of proton pump inhibitors (PPIs) or histamine H2-receptor antagonists (H2RAs), family history of GC and having performed an UGE. Results: Persistent epigastric pain was observed in 3.4% of the population. PUGB signs were observed in 3.3% of the population. The prevalence of PPIs and H2RAs use was 4.3% and 2.2% respectively, reaching 21.6% in people aged 70 years and older. Life span prevalence of UGE was 18.3%, with differences by region, health insurance and educational level. UGE coverage in people aged 40 years or older with and without persistent epigastric pain was 14.4% and 3.2% respectively (Odds ratio 4.8, p < 0.01). The prevalence of UGE was similar among people with or without PUGB or family history of CG. Conclusions: The estimated coverage of the current GC prevention strategy in Chile is 14.4%, evaluated at a population level. Further studies are required to determine the impact of this strategy on early GC diagnosis and mortality.

Background: In Chile, gallbladder cancer (GBC) is one of the most important causes of death and gallstone disease (GSD) is its main risk factor. Abdominal ultrasonography (AU) is used for the diagnosis of GSD and cholecystectomy is used to prevent it. Aim: To estimate GSD prevalence in the general population and to assess the diagnostic and therapeutic coverage of GSD as a preventive strategy for GBC in Chile. Material and Methods: A standardized digestive symptoms questionnaire of the 2009-2010 Chilean National Health Survey was answered by 5412 adults over 15 years old. Self-reports of AU, GBD and cholecystectomies were recorded. Results: The prevalence of biliary-type pain was 7.1%. During the last five years, the prevalence of AU was 16%. GSD was reported in 20% of these tests and 84% of them were asymptomatic. The prevalence of AU was significantly lower in Araucanía region and among people with less than 12 years of education. Life cholecystectomy prevalence was 11% and reached 40% in people aged over 60 years. Women accounted for 75% of total cholecystectomies. Twenty-one percent of individuals who referred biliary-type pain, were studied with an AU. Only 60% of people with GSD confirmed by AU underwent a cholecystectomy. Conclusions: GSD affects at least 27% of the Chilean adult population. Important deficits and inequities in GSD diagnostic and therapeutic coverage were identified.

Background: To correctly interpret spirometric results, reference values should come from the same population. Current spirometric reference equations have been under scrutiny due to deficiencies to fit adequately for Chilean population, specially, for those aged over 65 years old. Aim: To develop new spirometric reference values for Chilean adults, based on national studies in which spirometries were performed in healthy non-smoker adults. Material and Methods: A standardized database of spirometric values was developed combining spirometric data collected from five population-based studies, in which healthy nonsmoker adults participated. Spirometries from 448 males aged 19 to 84 years and from 726 females aged 19 to 94 years, obtained according to guidelines from the American Thoracic and European Respiratory Societies, were analyzed. Using multiple regression models, which included height, gender, and age, the theoretical value and inferior limits of normality were calculated for 1st second (FEV1), forced vital capacity (FVC), FEV1/FVC, and forced mid-expiratory flow rate (FEF25-75). Results: Reference values and lower limits of normality (LLN) were constructed for Chilean adults of both genders. The new proposed set of equations had a better fit, when compared with the current reference values used in Chile. Conclusions: The new spirometric references values derived from this study, fit better than currently used ones. Therefore, they should be used as new references values for Chilean adults.

Más de 700.000 casos y alrededor de 6.000 muertes se produjeron en la última epidemia de cólera registrada en América Latina, ocurrida en 1991. Esta se inició en el Perú y se propagó de país en país, afectando a la mayor parte de la región, incluyendo Chile. Comparado al Perú, la epidemia en Chile tuvo consecuencias menores debido a las medidas adoptadas por el Sistema Nacional de Servicios de Salud, en conjunto con otras entidades del Estado. Dentro de estas medidas destacan el establecimiento del Consejo Nacional de Salud, la planificación estratégica de los Servicios de Salud, el fortalecimiento de los Sistemas de Vigilancia Epidemiológica y de Laboratorios Clínicos y Ambientales, la educación de la población y las estrategias de prevención. La mantención de las medidas de sanidad ambiental y la colaboración de la población son fundamentales para evitar la aparición futura de la enfermedad. During the latest Latin American epidemic of cholera (1991), more than 70,000 cases were identified and over 6,000 deaths occurred. Cholera started in Peru and expanded to the rest of Latin American countries, including Chile. Compared to Peru, the epidemic in Chile had minor consequences due to the strategies adopted by the National System of Health Services, together with other public institutions. These strategies included the establishment of a National Committee for Cholera, strategic planning of health services, strengthening of epidemiologic surveillance systems and of clinical and environmental laboratories, education of the population, and preventive strategies, among others. Maintenance of environmental health measures and the population’s collaboration are essential to avoid future emergence of this disease.

El objetivo de la comunicación fue evaluar la asociación entre contaminación intradomiciliaria (CID) y la presencia de síntomas respiratorios crónicos (SRC) y Enfermedad Pulmonar Obstructiva Crónica (EPOC). Se analizó información del estudio de prevalencia Platino en base a una muestra de población general de 1.208 sujetos de 40 y más años de Santiago, Chile. Se analizó la CID derivada del uso de combustibles sólidos, exposición a humo ambiental (EHAT) y el reporte de exposición previa a polvo de origen ocupacional calculando Odds Ratio de Prevalencia (ORP) crudos y ajustados por potenciales variables confundentes. Las variables que determinan mayor riesgo de EPOC fueron edad mayor 60 años (ORP 3,9; IC95% 2,9-5,4; p < 0,01) y sexo masculino (OR 2,08; IC95% 1,5-2,8; p < 0,01). La CID derivada de carbón se asoció con síntomas respiratorios crónicos (ORP 1,4; IC95% 1,05-1,89; p = 0,024), al igual que el antecedente de exposición a humo de leña (ORP 1,4, IC95% 1,04-1,9; p = 0,029) y EHAT (ORP 2,1, IC95% 1,2-3,7; p = 0,006). La exposición a carbón, leña y EHAT constituyen factores de riesgo independientes para presentar SRC. No se encontró asociación entre CID y EPOC. The aim of this study is to report the association between indoor pollution (IP), chronic respiratory symptoms (CRS) and chronic obstructive pulmonary disease (COPD). Data provided from PLATINO study considering a sample of 1.208 subjects 40 and over years old population in Santiago, Chile. Analyses regarding indoor air pollution variables, smoking, environmental tobacco smoke (ETS) and lifetime exposure to occupational dust and CRS and COPD as main outcomes was performed. Crude and adjusted prevalence odds ratios (POR) were calculated using logistic regression, adjusting for potential confounders. Variables explaining higher COPD risk were age > 60 years (POR 3.94, CI95% 2.87-5.41, p < 0.01) and males (POR 2.08, CI95% 1.53-2.83, p < 0.01). Exposure to coal IP was associated with CRS (POR 1.41, CI95% 1.05-1.89; p = 0.024), as well as exposure to fi rewood IP (POR 1.42, CI95% 1.04-1.93; p = 0.029) and ETS (POR 2.15, CI95% 1.24-3.73, p = 0.006). Exposure to coal, firewood and ETS are independent risk factors for CRS. Association between exposure to IP and COPD was not observed.

La actual disponibilidad de programas de detección y tratamiento de enfermedades respiratorias en Chile ha determinado una mayor utilización de la espirometría en el diagnóstico de dichas enfermedades. La adecuada interpretación de los resultados de la espirometría requiere disponer de patrones de referencia idealmente originados en la misma población en la cual se utilizarán. Para facilitar el uso y aplicación de nuevas ecuaciones de referencia espirométricas recientemente modeladas en población adulta chilena, se presentan nomogramas diseñados para cada uno de los parámetros en base al género, edad y talla para sujetos entre 19 y 50 años y en mayores de 51 años. Estas ecuaciones derivan de 5 estudios nacionales que incluyeron población que cumplió criterios universales para determinar valores de referencia, (1.174 sujetos, 19 a 94 años), que efectuaron espirometrías siguiendo recomendaciones internacionales (ATS). As a result of the availability of programmes to detect and treat respiratory disease in Chile there has been a greater use of spirometry in diagnosis. To be able to correctly interpret spirometry results there must be reference patterns which, ideally come from the same population in which they will be used. In order to facilitate the use and application of new spirometric reference equations recently calculated for the adult population, there follows a series of nomograms. These nomograms have been designed for each of the following parameters: gender, age, and size of subjects between 19 and 50 years old and also for subjects over 51 years old. These equations are taken from 5 national studies. These studies included a population which complied with universal criteria to determine reference values ( 1.174 subjects, between 19 and 94 years old), spirometries were carried out on this population following international recommendations (ATS).

Background: Asthma prevalence is increasing worldwide, especially in developing countries. Aim: To determine the prevalence of asthma diagnosis and related symptoms in children, its changes during a 6-year period and the iníluence exerted by socioeconomic status. Materials and methods: Cross-sectional study conducted among school children of Santiago. A sample of 4,561 children aged 6-7 and 13-14 years attending public schools (central district, medium-low and low socioeconomic status) and prívate schools (eastern distrícts, high socioecomic status) were surveyed. Dependent variables were asthma diagnosis (AD), wheezing duríng the last 12 months (WHE12) and frequency of episodes of wheezing (FEW). Prevalence odds ratios were calculated using regression models, adjusted for several confounding variables. Results: AD prevalence for the group as a whole was higher in boys than in girls (13.2% and 10.8%, respectively p =0.016). Prevalence rate of AD was also higher for children aged 13-14 than 6-7 years (13.8% and 10.1%, respectively p

Para la comunidad científica mundial, el aumento progresivo de la temperatura del clima planetario es un hecho inequívoco, proyectándose para el año 2100 un incremento de la temperatura promedio de 1,0 °C - 3,5 °C. Las consecuencias pronosticadas son muy diversas, siendo en su mayoría adversas para la salud humana, entre las cuales se incluyen el establecimiento de escenarios epidemiológicos propicios para la emergencia y reemergencia de enfermedades infecciosas. El presente artículo sintetiza la evidencia disponible en torno a los mecanismos generadores del cambio climático, sus efectos medioambientales y sus consecuencias sobre la salud humana. Para ello, se describen cambios ya objetivados en la dinámica de enfermedades zoonóticas y vectoriales y de enfermedades transmitidas por agua y alimentos. Se comenta la posición de Chile en el concierto internacional y sus múltiples desafíos pendientes, destacándose la importancia de incorporar al debate nacional a profesionales que trabajan en el sector salud. For the international scientific community, it is undoubted that planetary temperature is increasing, being projected an average raise of 1.0 °C-3.5 °C by the year 2100. Forecasted consequences are diverse, most of them adverse for human health, including the establishment of favorable epidemiological scenarios for the emergence and reemergence of infectious diseases. The present article summarizes the available evidence regarding the mechanisms that promote climate change, its environmental effects and its consequences on human health. In order to accomplish this objective, demonstrated changes in the dynamics of zoonotic, vectorial, food and water-borne diseases are described. The position of Chile in the international community is commented, as well as múltiple pending challenges, among which outstands the importance of incorporating professionals that work in the health sector to the national debate.

Cystic fibrosis (CF) is the most common lethal autosomic recessive disease among Caucasians. In Chile, its incidence is estimated in 1/4,000 newborns and it is possibly underestimated. Aim: To analyze CF mortality in Chile during the period 1997-2003. Material and methods: Demographic and CF mortality data reported by the National Institute of Statistics during the period 1997-2003 were recorded, according to sex and age. Overall mortality rate for each year was estimated, as well as the average mortality rate during the same period in patients younger than 1 year, 1-4 years, 5-9 years, 10-14 years and older than 15 years. Results: One hundred and three deaths (56 females) due to CF occurred during 1997-2003. Sixty-eight deaths corresponded to patients younger than 15years (66.0%). Overall mortality rate ranged from 0.82 to 1.33 per 10(6) inhabitants in 1997 and 1999, respectively. Average mortality rate ranged from 0.46 to 9.81 per ^inhabitants among patients older than 15 years and younger than 1 year, respectively. Conclusions: Most CF deaths occurred in the pediatric age group

John Snow (1813-1858) fue un brillante médico inglés. Desde temprana edad destacó por su agudo sentido de observación, razonamiento lógico y perseverancia, primero en el ámbito de la anestesia y posteriormente en epidemiología. Los sucesivos brotes de cólera que afectaron a la ciudad de Londres, lo motivaron a estudiar esta enfermedad desde un punto de vista poblacional, relacionando la incidencia de casos al consumo de aguas contaminadas por una "materia mórbida", responsable de la diarrea aguda con deshidratación que la caracteriza. En forma valerosa, Snow se opuso a las teorías vigentes de su época, sacrificando su prestigio. Fue pionero en el uso de metodologías de investigación epidemiológica moderna, por ejemplo, la implementación de encuestas y la epidemiología espacial. Con justa razón, hoy en día es considerado por la comunidad científica como el padre de la epidemiología moderna John Snow (1813-1858) was a brilliant British physician. Since young he stood out for his acute observation capacity, logical thinking and perseverance, first in anesthetics and later in epidemiology. The successive outbreaks of cholera that affected London, motivated him to study this disease from a populational point of view. He related the appearance of cases to the consumption of "morbid matter", responsible for the acute diarrhea with dehydration that characterizes this disease. Bravely, Snow opposed to certain theories present at his time, sacrificing his own prestige. He was a pioneer in the use of modern epidemiological investigation methodologies such as conducting surveys and spatial epidemiology. Fairly, he is considered nowadays as father of modern epidemiology by the scientific community

Background: Approximately one-third of vertebral fractures can be clinically diagnosed. Aim: To study the frequency of vertebral fractures in postmenopausal women. Patients and methods: We recruited 555 postmenopausal women from Santiago, Chile, aged 55-84 years, who manifested interest in their bone health. All were healthy by self-declaration and by general clinical and laboratory tests and had not taken any bone-active therapy. They all underwent a spine and femoral neck (FN) densitometry and a digital lateral spine X-ray from T4 to L4 was obtained. PTH, calcidiol, and other parameters of calcium metabolism were also measured. Results: Overall, 142 of 478 patients with a complete study (29.7%) had at least one vertebral fracture. The proportion of women with fractures increased with age. A T score below -2.5 in the spine and hip was found in 32% and 14% of women, respectively. The proportion of women with spinal opeoporosis doubled between ages 55-70 and remained constant afterwards. In contrast, at the femoral neck, this proportion increased progressively reaching 53.3% at age 80-85. However, 56% of patients with vertebral fractures did not have densitometric osteoporosis in any location. Calcidiol levels were 16.8±6.8 ng/mL. With a cutoff point of 17 ng/mL, 47.5% of the patients had hypovitaminosis D. There was no association between calcidiol levels and vertebral fractures or bone density at the spine or femoral neck. Patients with fractures differed from those without fractures in that they had significantly lower bone density at the spine and hip and were older (p

The model of epidemiological transition proposed by Omram explains the changes in disease patterns in communities. In societies with a high level of development this model has been complemented with the study of the post transition process. In this context, the emergence of allergic diseases, asthma and subsequently, of autoimmune diseases, has reached worrisome proportions in some countries, and no model can explain these changes. The hygiene theory supported by Strachan gives a reasonable explanation to this phenomenon. It postulates that the reduction of early exposure to biological agents, along with an improvement of sanitation conditions, immunizations and medical therapies, causes an asymmetrical immunological response, favoring the expression of Th2 response. The hygiene theory does not fully explain by itself what is happening in developed countries and it is not universally accepted. Chile is experiencing an epidemiological transition from a high burden of infectious diseases to a growing prevalence of non communicable diseases. In a previous similar setting in developed countries, there is some evidence to suspect that asthma, allergic and autoimmune diseases are becoming part of the epidemiological situation of Chile

The model of epidemiological transition proposed by Omram explains the changes in disease patterns in communities. In societies with a high level of development this model has been complemented with the study of the post transition process. In this context, the emergence of allergic diseases, asthma and subsequently, of autoimmune diseases, has reached worrisome proportions in some countries, and no model can explain these changes. The hygiene theory supported by Strachan gives a reasonable explanation to this phenomenon. It postulates that the reduction of early exposure to biological agents, along with an improvement of sanitation conditions, immunizations and medical therapies, causes an asymmetrical immunological response, favoring the expression of Th2 response. The hygiene theory does not fully explain by itself what is happening in developed countries and it is not universally accepted. Chile is experiencing an epidemiological transition from a high burden of infectious diseases to a growing prevalence of non communicable diseases. In a previous similar setting in developed countries, there is some evidence to suspect that asthma, allergic and autoimmune diseases are becoming part of the epidemiological situation of Chile

Background: The prevalence of asthma and allergic rhinitis experienced a steady increase in the last years, probably associated to changes in lifestyles. Aim: To assess the prevalence of allergic rhinitis, to evaluate changes over time (1994-2000), and to describe risk factors. Material and Methods: The International Study of Asthma and Allergies in Childhood (ISAAC) core questionnaire, with questions added about socioeconomic status (SES), was applied to 4594 children between 6-7 years old and 13-14 years old during october-december 2000. Attendance to public or private schools was also used a SES proxy. The results were compared with those of a similar survey in 5281 children, performed in 1994. Rhinitis symptoms (ever) (SR), rhinitis symptoms within last 12 months (SR12) and medical diagnosis of rhinitis (DR) were assessed. Results: There was a significant increase in the prevalence of SR, SR 12 and DR in both age groups in 2000, compared to 1994. SR older children showed a higher prevalence of SR compared with the youngest group (p=0.003). No age differences were observed in the prevalence of SR12 and DR. Both SR and SR12 were more prevalent at schools of medium and low-medium SES (p=0.003 and p=0.002 respectively). DR was significantly more prevalent among children of high SES. A better mother educational level was associated to higher prevalence of SR and SR12 (p=0.03 and p=0.04). Father educational level was associated to DR (p=0.007). The prevalence of SR12 was higher in households with carpets (p=0.017). The prevalence of DR was higher in houses with smokers (p=0.03) and gas heating (p=0.005). None of the three variables were related to gender. Conclusions: The prevalence of SR, SR12 and DR increased significantly in a short time period (6 years). Our results support a positive association between DR and high SES

La espirometría es el examen más utilizado para evaluar la función pulmonar y ocasionalmente se usa en estudios epidemiológicos. Evaluamos si las variables: sexo, edad, nivel socioeconómico, escolaridad, IMC, cursar concomitantemente con resfrío, tabaquismo, fecha del examen, haberse efectuado espirometría anteriormente y técnico responsable, se asociaban con la probabilidad de espirometrías insatisfactorias en una primera sesión. Quince enfermeras y una matrona que recibieron capacitación realizaron las espirometrías en 1.168 sujetos empleando un espirómetro Easy One NDD. En la primera sesión 1.037 individuos (88,8%) efectuaron una espirometría satisfactoria fracasando 131 (11,2%). Se identificaron dos variables predictoras del fracaso: edad y años de instrucción. Las causas más frecuentes de espirometrías insatisfactorias fueron: 1) No cumplir con criterios de aceptabilidad (77,1 %); 2) Falta de reproducibilidad (67,9%); 3) Caída de CVF post broncodilatador sin cambio en el VEF1 (36,6 %). De los 131 sujetos cuya espirometría fue insatisfactoria en la primera sesión, ochenta y nueve aceptaron repetirla, lográndose al final del estudio una espirometría satisfactoria en el 95,5% de la muestra. Personal técnico sin experiencia previa y adecuadamente entrenado, es capaz de lograr espirometrías de buena calidad en un estudio epidemiológico de campo. Las causas más frecuentes de repetición de examen guardan relación con dificultad de alcanzar criterios de aceptabilidad y reproducibilidad de la prueba. Factores gravitantes en la repetición son la edad y el nivel de instrucción de los sujetos examinados. El desempeño de los técnicos no constituyó un factor limitante para obtener una adecuada calidad de la espirometría en terreno Spirometry, the most used test to evaluate pulmonary function, is only occasionally measured in field epidemiological studies. Our aim was to determine which of the following factors in the Platino study can be associated low quality spirometries in the first session: sex, age, socioeconomic level, educational level, body mass index, cold chill, smoking, operating technician, date and subject's previous spirometric experience. 1.168 individuals were evaluated with spirometry. Fifteen nurses and 1 midwife were trained according to NIOSCH standards. Easy One NDD spirometers were used. 1.037 subjects (88.8%) performed a satisfactory spirometry in the first session, and 131 (11.2%) failed to do so. Only two significant predictors of this failure were identified: age and educational level. Causes for test repetition were 1) Non satisfactory acceptability (77.1%); 2) lack of reproducibility (67.9%); 3) decline of post bronchodilator CVF without concomitant change in VEF1 (36.6%). Eighty nine of the 131 subjects accepted to repeat the test. A satisfactory spirometry was obtained in 79 subjects. Hence, at the end of the study 95.5 % of the subjects attained a satisfactory test. We conclude that personnel without experience, with appropriate training, can perform high quality field spirometries. Acceptability and repoducibility were the most sensitive factors associated with a bad performance of spirometry. Age and schooling were the main factors related with a low quality spirometry. No association was detected regarding technician as a predictor of low quality spirometries carried out in a population setting

La espirometría es el examen más utilizado para evaluar la función pulmonar y ocasionalmente se usa en estudios epidemiológicos. Evaluamos si las variables: sexo, edad, nivel socioeconómico, escolaridad, IMC, cursar concomitantemente con resfrío, tabaquismo, fecha del examen, haberse efectuado espirometría anteriormente y técnico responsable, se asociaban con la probabilidad de espirometrías insatisfactorias en una primera sesión. Quince enfermeras y una matrona que recibieron capacitación realizaron las espirometrías en 1.168 sujetos empleando un espirómetro Easy One NDD. En la primera sesión 1.037 individuos (88,8%) efectuaron una espirometría satisfactoria fracasando 131 (11,2%). Se identificaron dos variables predictoras del fracaso: edad y años de instrucción. Las causas más frecuentes de espirometrías insatisfactorias fueron: 1) No cumplir con criterios de aceptabilidad (77,1 %); 2) Falta de reproducibilidad (67,9%); 3) Caída de CVF post broncodilatador sin cambio en el VEF1 (36,6 %). De los 131 sujetos cuya espirometría fue insatisfactoria en la primera sesión, ochenta y nueve aceptaron repetirla, lográndose al final del estudio una espirometría satisfactoria en el 95,5% de la muestra. Personal técnico sin experiencia previa y adecuadamente entrenado, es capaz de lograr espirometrías de buena calidad en un estudio epidemiológico de campo. Las causas más frecuentes de repetición de examen guardan relación con dificultad de alcanzar criterios de aceptabilidad y reproducibilidad de la prueba. Factores gravitantes en la repetición son la edad y el nivel de instrucción de los sujetos examinados. El desempeño de los técnicos no constituyó un factor limitante para obtener una adecuada calidad de la espirometría en terreno

Las enfermedades respiratorias constituyen la tercera causa de muerte de la población chilena, siendo sólo superadas por las enfermedades del aparato circulatorio y los tumores malignos. El 50% de los decesos por enfermedades respiratorias en el adulto son atribuibles a la neumonía, siendo en Chile la principal causa de muerte por enfermedades infecciosas y la primera causa específica de muerte en la población senescente mayor de 80 años. La incidencia y letalidad de la neumonía adquirida en la comunidad (NAC) se elevan en las edades extremas de la vida (bajo un año de edad y sobre 65 años). En la población sobre 65 años de edad, la mortalidad se eleva en forma alarmante, alcanzando a 6,6 muertes por 1.000 personas. Se ha observado una gran variabilidad en la tasa de hospitalizaciones por neumonía en diferentes áreas geográficas, probablemente determinada por diferencias en los criterios empleados por los médicos para evaluar la gravedad de los enfermos, accesibilidad a los sistemas de salud y las características de la población examinada. Se estima que cerca de 20% de los pacientes con NAC requieren ser manejados en el hospital debido a la gravedad de la infección pulmonar, concentrándose en esta población el mayor riesgo de complicaciones, muerte y demanda de recursos de salud. Se han identificado algunas variables clínico-epidemiológicas capaces de modificar la forma de presentación y la gravedad de la enfermedad, tales como la edad avanzada, presencia de co-morbilidades, estado inmune del huésped, consumo de tabaco y alcohol, lugar de adquisición de la infección, el microorganismo causal y la contaminación ambiental Respiratory diseases represent the third cause of death in Chilean population, after cardiovascular diseases and malignancy. Fifty percent of deaths caused by respiratory diseases in adults are attributable to pneumonia. In Chile, they represent the main cause of death due to infectious diseases and the first specific one in senescent adults over 80 years old. The incidence and mortality of community acquired pneumonia (CAP) increase in both extreme ages of life (less than one year old and over 65 years old). In the population over 65 years old, mortality is extremely increased, rising to rates of 6.6 deaths per 1.000 inhabitants. High variability in pneumonia hospitalization rate has been observed in different geographic areas, probably due to different medical criteria used to evaluate the severity of illness, access to healthcare systems and characteristics of the evaluated population. About 20% of patients affected with CAP require hospitalization due to the severity of pulmonary infection and to the risk of complications or death, and the necessity of healthcare resources are focused in these patients. Several clinical-epidemiological parameters able to modify clinical presentation and severity of pneumonia have been identified, such as advanced age, presence of co-morbidities, host immune competence, tobacco and alcohol consumption, place of acquiring the infection, etiology and environmental pollution

Background: Well designed clinical trials yield the strongest evidence for the effect of health care interventions. Aim: To assess the methodological quality of the design and report of randomized clinical trials in a sample, published in biomedical Chilean journals between 1980 and 2002. Material and methods: All trials identified by hand search by the Unit of Evaluation of Technologies in Health, were assessed for quality of randomization, blinding, analysis of results and other characteristics of trial design, along with the application of Jadad's Score, that assesses the methodological quality of clinical trials in a scale that ranges from 0 to 5. Results: Twenty eight trials were found and assessed, 75% (n=21) specified the method used for randomization, 29% (n=8) described a correct allocation concealment and 39% (n=11) were double blinded. Withdrawals and dropouts were correctly reported in 21% (n=6) of the articles, whereas intention to treat analysis was done only in one. Thirteen trials had a Jadad score equal or higher than 3 points. Conclusions: Several design deficiencies were found in the trials assessed. It is difficult to know if methodological weaknesses are due to incomplete reports or to methodologically poor designs. Adopting initiatives like the CONSORT can help improve the quality of randomized clinical trials published in Biomedical Chilean journals

Background: Community acquired pneumonia (CAP) severity assessment is crucial. Aim: To develop a practical clinical severity assessment model for stratifying immunocompetent adult patients hospitalized with CAP into different management groups. Patients and methods: During a 24 months period, 455 adult patients (250 male, mean age 69±19 years old) were evaluated. All the relevant clinical information recorded and they were followed during hospital stay until discharge or death. Mortality until 30 days after admission was determined. Results: The mean hospital length of stay was 9.9±9.4 days and 76% had an underlying disease. In hospital mortality was 7.6% and 10.1% at 30 days follow up. Admission prognostic factors associated with high mortality at 30 days follow up were: advanced age, presence of comorbidity, suspicion of aspiration, duration of symptoms 2 days, altered mental status, absence of cough, fever and chills; low blood pressure, tachypnea, hypoxemia and multilobar radiographic pulmonary infiltrates. A clinical prognostic index derived from a logistic regression analysis including five independent variables associated with mortality (confusion, comorbidity, low systolic blood pressure, temperature 20/min), enabled patients to be stratified according to increasing risk of mortality: class 1: 0.9%, class 2: 4.9%, class 3: 14.2%, and class 4: 35.6%. Conclusion: A simple clinical severity assessment tool based on confusion, comorbidity, blood pressure, temperature and respiratory rate could be used to stratify patients with CAP into different risk class categories and management groups (Rev Méd Chile 2004; 132: 1037-46)

Background: By the year 2000, prostate cancer became the second leading cause of cancer death in Chilean men of all ages and is the leading cause of cancer deaths in men of eighty years of age or older. Aim: To analyze the trends in mortality rates from prostate cancer in Chile in a fifty years series, estimating the rate of increase of such rates and their changes in time. Material and methods: A trend analysis for age standardized mortality rates was performed, using join point regression analysis, which allows estimation of the annual percent change of rates and to find significant changes in such trend. Results: Age standardized mortality rates in Chile reached their peak value in 1996, becoming apparently stable from then on. Crude rates have had a steady increase during the whole period. The trends analysis identified three different periods in the growth of the age standardized rates: a first one of slow increase in rates between 1955 and 1981 (0.9% annual increase), a second one of more aggressive growth starting in 1981 (2.6% annual increase), and a third period starting in 1996, in which rates slowly decline at an annual rate of 1%. Conclusions: The tendency of prostate cancer seen in Chile resembles that of industrialized countries, with an increase in its age standardized death rates that suffers a downturn by the end of the past decade. Besides early detection techniques, a substantial part of the reduction in mortality from prostate cancer could be explained by therapeutic improvements (Rev Méd Chile 2004; 132: 579-87).

Background: In Chile, there is no information about the prevalence of smoking among basic and high school students. Aim: To study the prevalence of smoking among school age population. Material and Methods: A cross sectional survey was conducted during 2001, assessing tobacco use and smoking habit in a representative sample of 15.119 randomly selected students. Results: Sixty four percent of students had smoked at least once in their lifetime. Eighteen percent of students smoked daily and 15%, occasionally. The figures for women were higher (19 and 18% respectively). The mean age for the first contact with smoking was 12.3 years and, for starting the smoking habit, 13.2 years. Smokers increased the amount of cigarettes during weekends. Higher prevalence rates of smoking were observed in students from the Southern region of the country and of lower socioeconomic levels. From the 3rd grade on, there is an increased risk of having contact with tobacco and smoking for the first time and from 6th grade on, this risk becomes permanent. The adjusted Odds Ratio to be a smoker is significantly higher when the mother is a current or irregular smoker (OR 1.9 95 CI; 1.7-2.0). Conclusions: High smoking prevalence rates were detected in this survey, mainly in women. The risk for smoking starts early during school life. Therefore, health promotion programs must include elementary and high school students (Rev Méd Chile 2004; 132: 171-82)