Claudio Vargas

Childhood Environment and Atopic Conditions, with Emphasis on Asthma in a Chilean Agricultural Area

Background. An explanation of the etiology of atopic conditions based on the hygiene hypothesis remains controversial. Objective. To analyze exposure variables in childhood to assess their impact on hay fever, asthma, and sensitization. Methods . Data were collected on 1,232 young Chilean adults born between 1974 and 1978. Information was available on consultations for infections early in life, number of siblings, sharing a bedroom, nursery school attendance, and contact with animals in the first 5 years of life. Information on asthma symptoms and rhinitis were obtained from a standardized questionnaire. Sensitization to eight allergens and bronchial hyper responsiveness (BHR) to methacholine were assessed. The study design was non-concurrent longitudinal for infectious episodes and nutritional status in the first year and cross-sectional for the other outcomes. Results. Number of siblings was associated with sensitization only (p = 0.0048). Nursery school attendance was negatively associated with positive BHR (odds ratio (OR) 0.54, 95% CI 0.30–0.95). A severe respiratory infection early in life was protective of sensitization and wheeze combined (OR 0.29, 95%CI 0.12–0.74). Contact with dogs in the first year was a protective factor of rhinitis (OR 0.47, 95%CI 0.28-0.80), but contact with poultry and cats early in life increased the risk of rhinitis (OR 1.42, 95%CI 1.06–1.88; 1.82, 95%CI 1.06–3.14). Conclusion. The pattern of associations between environmental exposure in early life and atopic conditions was inconsistent. The significant associations were evenly distributed as protective and risk factors of atopic conditions.

Evolution of the nutritional situation of indigenous and non-indigenous Chilean schoolchildren

Background: Latin American countries show accelerated but ethnically or socially differentiated changes in their epidemiological profiles. Aim: The present study examined the evolution of the nutritional situation (1997–2005) in Chilean schoolchildren as related to ethnical origin (Mapuche). Subjects and methods: Using official databases, stunting (height/age ≤ − 2 z-scores), undernutrition (body mass index (BMI) ≤ − 2 z-scores) and obesity (BMI ≥95 percentile) were ascribed in first-grade schoolchildren. Ethnic groups were assigned by native parents’ surnames (none, one and two). Results: Based on 1 757 155 children (average age: 76.3 months), in 1997 stunting reached 8.4%, 4.8% and 3.1% in children with two, one and no Mapuche surnames, respectively. In 2005 it fell to 3.7%, 3.1% and 2.6% – a marked decrease in those with two Mapuche surnames (p<0.001). Obesity in 1997 was 11.8%, 12.8% and 13.3%, whilst in 2005 it changed to 17.5, 18.5 and 18.6%, respectively, demonstrating a similar trend to obesity in all groups (p=0.153). Undernutrition was rare (<1.1%) and stable. Poverty decreased clearly among the Mapuche population in this period. Conclusion: The marked decrease in stunting in children with a strong indigenous background seems related to a decrease in poverty over the period. Yet, the increase of obesity in all groups deserves further analysis.

Pobreza y procedencia indígena como factores de riesgo de problemas nutricionales de los niños que ingresan a la escuela

Objective. To estimate the effect of indigenous ancestry and poverty on nutritional outcomes in Chilean schoolchildren. Material and Methods. We used the national database of children entering to the public educational system in 1997-2004. This includes anthropometric assessment, socioeconomic status and parental surnames, used to derive the ethnic origin. Logistic regression models related poverty and ethnicity on stunting and obesity were done, controlling for sex, age and calendar year. Results. Data convey 1 580 103 children being 7.4% indigenous; 2.9% had stunting and around 16.0% were obese. Stratifying by poverty, it was shown that the poorest had higher risk of stunting both in indigenous (OR= 2.30; CI95%=2.27-2.33) and non indigenous (OR= 2.29; CI95%= 2.28-2.30). Conversely, poverty was a “protective factor” for obesity (OR= 0.63; CI95%= 0.62-0.64). Indigenous origin showed a significant OR slightly over the null. Conclusions. In Chilean children, poverty is a risk factor for stunting but still protects from obesity, independent of indigenous origin.

Impact of specific sensitization on asthma and rhinitis in young Brazilian and Chilean adults

Background The pattern of associations and the attributable fractions (AF) of atopic conditions due to specific sensitizations vary between countries.

Evolución del síndrome metabólico y de sus componentes en un seguimiento de 10 años en adultos de la Región de Valparaíso

Background: Metabolic syndrome is a risk factor for cardiovascular diseases and cancer. Its frequency is increasing steadily Aim: To evaluate the prevalence of metabolic syndrome (MS) and its components in a 10-year tracking study of young adults. Material and methods: Concurrent cohort study of subjects born between 1974 and 1978. They were evaluated between 2000 and 2002 and between 2010 and 2012 to determine the frequency of MS and its components (high blood glucose, waist circumference (WC), triglycerides, blood pressure and low HDL cholesterol), according to ATP III criteria. Attrition was handled using the reciprocal of the probability of remaining in the study. Result: During the first evaluation, the prevalence of metabolic syndrome was 9.3%, confidence interval (CI): 7.5-11.1), with no gender differences. Ten years later, the prevalence of MS increased significantly to 27.6% (CI: 24.7-29.9) and was more common in women than men (30.4 and 23.8% respectively, p<0.014). The components of MS also increased from one period to another: hyperglycemia, from 5.2% (CI: 4-7) to 24.4% (CI: 22-27); high triglyceride levels from 17.6% (CI: 15-20) to 35.3% (CI: 32-38); high blood pressure from 14.7 (CI: 13-18) to 30.2% (IC: 28-33) and high WC: 16.9% (CI: 15-19) to 41.5% (CI: 39-45). In both evaluations, there was a greater frequency of high triglycerides and high blood pressure among men, and greater frequency of low HDL and high WC among women. Hyperglycemia only showed differences by gender in the second measurement, and was greater among men. Conclusions: There was a marked increase in metabolic syndrome and its components in a 10-year interval, which is a warning sign of future cardiovascular risk.BACKGROUND Metabolic syndrome is a risk factor for cardiovascular diseases and cancer. Its frequency is increasing steadily Aim: To evaluate the prevalence of metabolic syndrome (MS) and its components in a 10-year tracking study of young adults. MATERIAL AND METHODS Concurrent cohort study of subjects born between 1974 and 1978. They were evaluated between 2000 and 2002 and between 2010 and 2012 to determine the frequency of MS and its components (high blood glucose, waist circumference [WC], triglycerides, blood pressure and low HDL cholesterol), according to ATP III criteria. Attrition was handled using the reciprocal of the probability of remaining in the study. RESULT During the first evaluation, the prevalence of metabolic syndrome was 9.3%, confidence interval (CI): 7.5-11.1), with no gender differences. Ten years later, the prevalence of MS increased significantly to 27.6% (CI: 24.7-29.9) and was more common in women than men (30.4 and 23.8% respectively, p < 0.014). The components of MS also increased from one period to another: hyperglycemia, from 5.2% (CI: 4-7) to 24.4% (CI: 22-27); high triglyceride levels from 17.6% (CI: 15-20) to 35.3% (CI: 32-38); high blood pressure from 14.7 (CI: 13-18) to 30.2% (IC: 28-33) and high WC: 16.9% (CI: 15-19) to 41.5% (CI: 39-45). In both evaluations, there was a greater frequency of high triglycerides and high blood pressure among men, and greater frequency of low HDL and high WC among women. Hyperglycemia only showed differences by gender in the second measurement, and was greater among men. CONCLUSIONS There was a marked increase in metabolic syndrome and its components in a 10-year interval, which is a warning sign of future cardiovascular risk.

Auditory responses in the eighth nerve of a mating call-less toad, Bufo chilensis (Amphibia: Bufonidae)

Abstract 1. 1. Responses of single auditory nerve fibers were recorded in Bufo chilensis . 2. 2. The characteristic frequencies of the units are distributed within the range of 0.1–1.4 kHz. 3. 3. Minimum thresholds of the most sensitive fibers indicate that the auditory sensitivity in the frequency range of the vocalizations of B. chilensis (0.9–1.4 Hz) is relatively elevated (above 50 dB SPL). 4. 4. This condition is concomitant with the lack of a mating call in this species and resembles the sensitivity reported in congeneric species which do not rely primarily on the mating call for pair formation.

Variación secular de los nacimientos, peso y longitud al nacer: perspectiva local

OBJECTIVE To analyse the outcomes of births and anthropometric measurements at birth of children born between 1974 and 2011 at Limache Hospital (Valparaíso, Chile). PATIENTS AND METHOD Times series were constructed of births, weight and length at birth, and low weight and length at birth. The trend was modelled with linear and logistical regressions using splines to represent breaks in the trend by decade. RESULTS The series includes 17,574 births. There was an increase in births per year in the 1970s (30/year) and declines in them to 17 and 22 births/year in the 1980s and 1990s, respectively (P<.001), with no significant trend thereafter. Newborns from 2000 to 2011 weighed 266 grams more than those in the 1970s (P<.001), and have now reached a mean weight of 3,530 g. Low birthweight fell from 8% in the 1970s to 1.1% after 2000. Birth length increased by 1cm in the 37 years studied, with a reduction of low birth length from 7.6% to 2.1% during the period. CONCLUSION Live births in the Limache Hospital declined, and anthropometric measurements at birth improved in the years analysed. This information is useful in developing interventions, taking into account the possible selection biases that could distort these estimates and their interpretation.

170 años de la Escuela de Medicina de la Universidad de Chile: su aporte a la salud infantil y del adolescente en Chile

Con una revision de la literatura biomedica pediatrica, el articulo revisa -en forma somera- la relacion que la Escuela de Medicina de la Universidad de Chile, primera creada en el pais y puesta en marcha en 1833, ha tenido con la evolucion de la salud infantil y adolescente de Chile en los 170 anos transcurridos desde su creacion. Con el tiempo, la Escuela origino la Facultad de Medicina de la misma universidad. Se destacan algunos hechos y nombres de personas que hicieron aportes de importancia al progreso de la educacion medica pediatrica y de la salud infantil y del adolescente