Association between medication and intestinal intussusception in children: a case-crossover study.

OBJECTIVES: This study aimed to assess the association between the appearance of intussusception in children and medication intake in the immediately preceding period (2-15 days). METHODS: A case-crossover design was used. We selected cases of children admitted with a diagnosis of intussusception (International Classification of Diseases, Ninth Revision, 860) to the major hospitals in the city of Valencia, Spain, from 2006 to 2009. We then estimated the association between the episode of intussusception and the intake of prescription medication during the preceding 2, 7, and 15 days (case period) and for the same time window 1, 2, 3, and 4 months prior (control period). Data on previous drug administration were obtained from the Pharmaceutical Service Manager System. RESULTS: A total of 95 cases (65.3% boys and 34.7% girls) were selected; 76.6% were younger than the age of 2 years. The association between intussusception and prior drug use varied depending on the exposure window: 15-day odds ratio (OR), 1.45 (95% confidence interval [95% CI], 0.86-2.43); 7-day OR, 1.46 (95% CI, 0.80-2.67); and 2-day OR, 2.26 (95% CI, 1.10-4.64). These associations were greater for children aged younger than 2 years and were usually due to the recent administration (preceding 2 days) of antibiotics (OR, 8.00; 95% CI, 1.47-43.7). CONCLUSIONS: Intussusception was more common among boys aged younger than 2 years. A positive and significant association was observed when drugs were administered 2 to 7 days before the onset of symptoms in children younger than the age of 2 years.

Prenatal exposure to cooking gas and respiratory health in infants is modified by tobacco smoke exposure and diet in the INMA birth cohort study.

BACKGROUND: Studies that have evaluated the association between exposure to gas appliances emissions at home with respiratory health in children obtained heterogeneous and limited results. The aim of this study is to analyze the association between the use of gas cooking at home during pregnancy and respiratory problems in children during their first year of life. METHODS: In the years 2003 through 2008 pregnant women were enrolled in 4 Spanish areas and visited in different age-points following a common protocol. Outcomes studied (from a questionnaire) were any episode of lower respiratory tract infection (LRTI), wheezing, persistent cough, chestiness and otitis. The association between exposure to gas cooking at home and respiratory outcomes was assessed using logistic regression and adjusting by confounding variables. Some potential effect modifiers (i.e. smoking, fruit and vegetables consumption) were examined. RESULTS: Among the 2003 children included in the study, a total of 731 (36.6%) had a LRTI episode, 693 (34.6%) experienced wheezing, 302 (15.5%) a persistent cough, 939 (47.4%) chestiness and 620 (31.2%) had an episode of otitis during their first year of life. Gas cookers were present in 45.5% of homes. Exposure to gas cooking in homes was not associated with respiratory outcomes Odds Ratios (OR) were close to 1 and not statistically significant. However, a positive association was found for otitis among infants whose mothers reported low intakes of fruit and vegetables during pregnancy [OR (95% CI) = 1.38 (1.01-1.9)] and also wheezing and chestiness were associated with gas cookers among those children whose mothers smoked during pregnancy. CONCLUSIONS: In susceptible subjects (those whose mothers smoke and consumed below average fruit and vegetables) we found an association between exposure to gas cooking during pregnancy and risk of wheezing, chestiness and otitis during the first year of life. But more research is needed regarding not only gas cooking and respiratory health but also the possible effect modifier role of diet and tobacco.

Outdoor, but not indoor, nitrogen dioxide exposure is associated with persistent cough during the first year of life.

BACKGROUND AND AIMS: Because their lungs and immune system are not completely developed, children are more susceptible to respiratory disease and more vulnerable to ambient pollution. We assessed the relation between prenatal and postnatal nitrogen dioxide (NO(2)) levels and the development of lower respiratory tract infections (LRTI), wheezing and persistent cough during the first year of life. METHODS: The study population consisted of 352 children from a birth cohort in Valencia, Spain. Prenatal exposure to NO(2), a marker of traffic related air pollution was measured at 93 sampling sites spread over the study area during four different sampling periods of 7 days each. It was modeled for each residential address through land use regression using the empirical measurements and data from geographic information systems. Postnatal exposure was measured once inside and outside each home using passive samplers for a period of 14 days. Outcomes studied were any episode of LRTI during the child's first year of life diagnosed by a doctor (bronchitis, bronchiolitis or pneumonia), wheezing (defined as whistling sounds coming from the chest), and persistent cough (more than three consecutive weeks). Outcomes and potential confounders were obtained from structured questionnaires. Multiple logistic regression was used to identify associations. RESULTS: The cumulative incidence (CI) at first year of life was 30.4% for LRTI (23.0% bronchiolitis, 11.9% bronchitis and 1.4% pneumonia), 26.1% for wheezing and 6.3% for persistent cough. The adjusted odds ratio (95% confidence interval) per 10µg/m(3) increment in postnatal outdoor NO(2) concentration was 1.40 (1.02-1.92) for persistent cough. We also found some pattern of association with LRTI, bronchiolitis, bronchitis, wheezing and persistent cough in different prenatal periods, although it was not statistically significant. CONCLUSIONS: Our results indicate that exposure to outdoor, but not indoor, NO(2) during the first year of life increases the risk of persistent cough.

Indoor and outdoor air concentrations of BTEX and determinants in a cohort of one-year old children in Valencia, Spain.

BTEX is the commonly used term for a group of toxic compounds (benzene, toluene, ethyl benzene, ortho-xylene and meta- and para-xylene), some of which, most notably benzene, are known carcinogens. The aim of this study is to measure the BTEX levels both inside and outside the homes of 352 one-year old children from the Valencia cohort of the INMA study (Spain) and to analyze the determinants of these levels. Passive samplers were used to measure BTEX levels during a 15day period and a questionnaire was administered to gather information on potentially associated factors (sociodemographics, residential conditions, and lifestyle). The average concentrations of benzene, toluene, ethyl benzene, ortho-xylene, and meta- and para-xylene were 0.9, 3.6, 0.6, 0.6, and 1.0µg/m(3), respectively. On average, the indoor levels of all the compounds were approximately 2.5 times higher than those observed outdoors. Factors associated with higher BTEX concentrations inside the home were being the child of a mother of non-Spanish origin, living in a house that had been painted within the last year, living in an apartment, and not having air conditioning. Higher outdoor concentrations of BTEX depend on the residence being situated in a more urban zone, being located within the city limits, having living in a building with more than one story, residing in an area with a greater frequency of traffic, and the season of the year in which the sample was taken. The data thus obtained provide helpful information not only for implementing measures to reduce exposure to these pollutants, but also for evaluating the relation between such exposure and possible health risks for the children in the cohort.

Short-term relationship between meteorological variables and hip fractures: an analysis carried out in a health area of the Autonomous Region of Valencia, Spain (1996-2005).

INTRODUCTION: Diverse studies have shown a seasonal influence on the incidence of hip fracture (HF), possibly associated with adverse meteorological conditions. In this paper, we present an analysis of the short-term relationship between meteorological conditions and the incidence of HF in people over 45 years of age living in a Mediterranean climate zone. MATERIAL AND METHODS: HF cases admitted to the two reference hospitals in the health area were selected. The meteorological variables (temperature, relative humidity, rain, wind, and other conditions) were obtained from a weather station centrally located within the area under study. The trend and seasonality of the time series were analyzed with the aid of Poisson regression modeling. The relationship between the incidence of a hip fracture and the meteorological conditions, both on the same day and on the day previous to the patient's admission to the hospital were correlated in a case-crossover analysis with the control periods selected in accordance with two different methods of approximation (symmetric and semi-metric). The results were analyzed for different subgroups defined by age (older or younger than 75 years of age) and sex of subject and by type of fracture (cervical or pertrochanteric). RESULTS: 2121 patients admitted for HF were selected. Of these, 1598 (75.3%) were women and 523 (24.7%) were men. The average age of the subjects was 80, with patients ranging from 45-99 years of age. The time/weather series showed a positive tendency, with a greater occurrence of cases in the autumn and winter months. The case-crossover analysis showed a significant relationship between the daily duration of wind and the incidence of HFs. Divided into quartiles, the windiest days (quartile 4) were associated with a 32% increased risk of HF (OR 1.32 CI 95% 1.10-1.58) with respect to the calmest days (quartile 1), especially in patients under 75 (OR 1.53; CI 95% 1.02-2.29). The remaining meteorological variables were not associated in any significant fashion with the incidence of HFs. The results were comparable across different subgroups classified by age, sex, and type of fracture. CONCLUSIONS: The incidence of HFs varies seasonally and presents a significant association with the coldest times of the year. In the short-term, lasting windy periods are associated with an increased risk of HFs whereas other meteorological variables show a much lower, non-significant correlation.

Levels of pollutants in indoor air and respiratory health in preschool children: a systematic review.

The aim of this paper is thus to identify, evaluate, and summarize in a systematic fashion all the epidemiological studies that have analyzed the association between exposure to specific indoor air pollutants and respiratory disease among children under the age of five. A search was carried out in the main biomedical bibliographic sources in December 2006 and updated in February 2008. The study period covered 12 years (1996-2007). All the selected papers were carefully read. We focused on studies that analyzed at least one indicator of respiratory health and which included one or more indoor air pollutants in relation to the respiratory health of children under the age of 5. Studies that analyzed passive smoking as the sole source of indoor air pollution were not included. Fourteen studies were considered to be relevant. The most analyzed pollutant was nitrogen dioxide, followed by volatile organic compounds, airborne particulates and other pollutants; phthalates and CO(2). The literature reviewed within our criteria seems to indicate that several indoor pollutants, even at the moderate levels found in the developed countries, could be harmful to the respiratory health of very young children. Future research should focus on conducting more studies, preferably making use of cohorts, with adequate techniques for measuring indoor pollution levels.

Sources of indoor air pollution and respiratory health in preschool children.

We carried out bibliographic searches in PubMed and Embase.com for the period from 1996 to 2008 with the aim of reviewing the scientific literature on the relationship between various sources of indoor air pollution and the respiratory health of children under the age of five. Those studies that included adjusted correlation measurements for the most important confounding variables and which had an adequate population size were considered to be more relevant. The results concerning the relationship between gas energy sources and children's respiratory health were heterogeneous. Indoor air pollution from biomass combustion in the poorest countries was found to be an important risk factor for lower respiratory tract infections. Solvents involved in redecorating, DYI work, painting, and so forth, were found to be related to an increased risk for general respiratory problems. The distribution of papers depending on the pollution source showed a clear relationship with life-style and the level of development.

Environmental factors affecting children's respiratory health in the first years of life: a review of the scientific literature.

The aim of this paper is to quantitatively summarize the original articles on the relationship between environmental hazards and respiratory health in young children. A search was carried out in the main biomedical bibliographical sources in December 2006 and then the results were updated in June 2007. The study period covered 11 years (1996-2006). The information was assessed by reviewing the abstracts. Six hundred and forty documents were recovered. Documents from the United States accounted for 23.5% of articles. The production tended to increase over the study period. The factor most widely studied was air pollution, with outdoor air pollution being studied more (just over 50% of articles) than indoor air pollution (40%). Asthma was the most often studied condition (75% of articles). In a third of the cases, the information was obtained from hospital or health center records, and in 20% from questionnaires. The main diagnostic criterion was clinical. Infection of the inferior respiratory tracts predominated in children less than 3 years of age. An awareness of the role played by pollution and environmental hazards is fundamental in the management and prevention of respiratory problems in childhood, and this is reflected in the literature reviewed. However, very few synthesis studies have been carried out on this matter.