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The influence of maternal drinking and drug use on the quality of the home environment of school-aged children.

BACKGROUND: Although many studies have examined the development of children of male alcoholics, few studies have considered substance use by the female caregiver. This study evaluated the relationship between substance use by female caregivers and factors that affect the child-rearing environment. METHODS: A total of 480 inner-city African-American women were recruited during pregnancy for a longitudinal study of the effects of prenatal alcohol use and substance use by caregivers on the development of their children. All women were screened for alcohol consumption at their first prenatal visit to a large urban maternity hospital. Those who averaged seven or more drinks per week (0.5 oz absolute alcohol per day) at the time of conception were invited to participate in the study, as was a 5% random sample of lighter drinkers and abstainers. At the 7.5-year follow-up assessment, the quantity and frequency of alcohol consumption and drug use, as well as several measures of the child-rearing environment, were assessed for 231 of the caregivers. RESULTS: Current alcohol use was uncorrelated with standard demographic factors, such as socioeconomic status, but was related to poorer family functioning, lower quality of parental intellectual stimulation, and higher levels of domestic violence. There were independent effects of illicit drug use on family environment, domestic violence, and caregiver depression. History of drinking during pregnancy, however, was not related to the current child-rearing environment. Poorer parental functioning generally was found only among the caregivers who currently drank both heavily (six or more drinks/occasion) and frequently (three or more days/week). After controlling for lifetime alcohol problems, current drinking still predicted a less cohesive and organized family environment and higher levels of domestic violence. CONCLUSIONS: Current heavy, frequent drinking in this relatively homogenous, economically disadvantaged sample was unrelated to demographics and seemed to have an important negative impact on the quality of the child-rearing environment, whereas drinking during pregnancy was unrelated to the current child-rearing environment.

Adult↗

Calcium localization in lettuce leaves with and without tipburn: comparison of controlled-environment and field-grown plants.

An electron microprobe was used to determine tissue concentrations of Ca across 20-mm-long leaves of 'Green Lakes' crisphead lettuce (Lactuca sativa L.) with and without tipburn injury. Concentrations within the fifth and 14th leaves, counted from the cotyledons, from plants grown under controlled-environment conditions were compared to concentrations within similar leaves obtained from plants grown under field conditions. Only the 14th leaf from plants grown under controlled-environment conditions developed tipburn. Injured areas on these leaves had Ca concentrations as low as 0.2 to 0.3 mg g-1 dry weight. Uninjured areas of tipburned leaves contained from 0.4 to 0.5 mg g-1 dry weight. Concentrations across the uninjured 14th leaf from field-grown plants averaged 1.0 mg g-1 dry weight. Amounts across the uninjured fifth leaves from both environments averaged 1.6 mg g-1 dry weight. In contrast, Mg concentrations were higher in injured leaves than in uninjured leaves and thus were negatively correlated with Ca concentrations. Magnesium concentrations averaged 4.7 mg g-1 dry weight in injured leaves compared with 3.4 mg g-1 dry weight in uninjured leaves from both environments. Magnesium concentrations were uniform across the leaf. Potassium concentrations were highest at the leaf apex and decreased toward the base and also decreased from the midrib to the margin. Potassium averaged 51 mg g-1 dry weight in injured and uninjured leaves from both environments. No significant differences in K concentration were present between injured and uninjured leaves. This study documented that deficient concentrations of Ca were present in areas of leaf tissue developing tipburn symptoms and that concentrations were significantly higher in similar areas of other leaves that had no symptoms. This study also documented that Ca concentrations were significantly lower in enclosed leaves that exhibited tipburn symptoms than in exposed leaves that did not exhibit tipburn. Also, the amounts of Ca in plants that developed tipburn in controlled environments were lower than in plants of the same cultivar that did not develop tipburn in field plantings. The reduced levels of Ca in plants grown in controlled environments were associated with faster development rates compared with field-grown plants.

Calcium↗

Does eating environment have an effect on food intake in the elderly?

Identical meals were prepared and served to 49 elderly subjects (mean age 74.3 +/- SD 7.7 years) in two different eating environments. The improved environment was a state of the art training restaurant and the standard environment was a staff canteen. Each subject was served an identical meal in both environments. The energy intake of each meal consumed was determined using the weighed intake method. There was a significant difference (p < 0.001) in the energy intake in the elderly between the improved (4894 +/- 613 kJ) and standard (4536 +/- 620 kJ) eating environments. Eating environment has a positive effect on the energy intake of elderly subjects. Changes to eating environment may be a useful way to improve energy intake in the elderly.

Aged↗

[Estimation on gene-environment interaction in the partial case-control study].

OBJECTIVE: To introduce the approaches for estimating gene-environment interaction based on partial case-control studies. METHODS: The effects of logistic model and log-linear model for estimating the main effects and gene-environment interaction effect were estimated by means of maximum likelihood methods in traditional case-control studies, case-only studies and partial case-control studies, respectively. An example was also illustrated. RESULTS: In traditional case-control study with complete data, the results of logistic model and log-linear model were equivalent. In case-only study without any information about controls, the logistic model can also efficiently estimate gene-environment interaction. In partial case-control study, environmental information was collected from all of the cases and controls, while genetic information was only collected from cases. For this case-control study with incomplete data, a suitable parameterized log-linear model could simultaneously and efficiently estimate the main effect of environment and gene-environment interaction, whereas the logistic model could not. CONCLUSION: For a partial case-control study, log-linear model could estimate not only the main effect of environment but also gene-environment interaction. If genotype and exposure were independent, estimators from partial case-control were as precisely as those from complete-data case-control studies.

Case-Control Studies↗

Is the rupture of cerebral berry aneurysms influenced by the perianeurysmal environment?

PURPOSE: To evaluate contact between cerebral berry aneurysms and the perianeurysmal environment and to study the influence this contact has on aneurysm rupture. MATERIALS AND METHODS: In a series of 76 consecutive patients, pre- and post-contrast CT images of 87 aneurysms were evaluated. Aneurysm locations were identified and aneurysms were divided into two different groups depending on whether they had ruptured or not. Contact between aneurysms and the perianeurysmal environment was studied when present, and considered to be balanced or unbalanced according to symmetry of contact and type of contact interface, i.e. with bone, dura, etc. RESULTS: Rupture occurred in 47 aneurysms at an average maximum dome size of 7.4 mm. There was contact with elements of the perianeurysmal environment in 38 (81%) of ruptured cases and no evidence of contact in 7 (15%). The nature of contact was unclear in 2 (4%) ruptured aneurysms. In the aneurysms with contact, the nature of contact was unbalanced in 34 (72%) and balanced in 4 (9%). Unbalanced aneurysms ruptured at significantly smaller sizes (average: 7.7 mm) than balanced aneurysms (average: 11.4 mm). Seven aneurysms of small size (3.3-6.9 mm, average: 4.8 mm) were found to have ruptured, despite the fact that they were too small to exhibit contact with the perianeurysmal environment. In 40 unruptured aneurysms (average size: 6.3 mm), contact with the perianeurysmal environment was found in 15 aneurysms, for which balanced contact was found in 11 (27.5%) and unbalanced contact in 4 (10%), and no contact in 25 (62.5%). The average size of the aneurysms without contact (3.7 mm) was significantly smaller than that with balanced contact (10.3 mm) or with unbalanced contact (11.3 mm). CONCLUSION: Aneurysms exhibit contact with their perianeurysmal environment as soon as they reach a size that exceeds their allowance given by the local subarachnoid space. The contact with the environment was found to be an additional determinant parameter in the evolution of cerebral berry aneurysms and their risk to rupture.

Adult↗

Assessing the importance of genotype x environment interaction for root traits in rice using a mapping population. I: a soil-filled box screen.

Altering root system architecture is considered a method of improving crop water and soil nutrient capture. The analysis of quantitative trait loci (QTLs) for root traits has revealed inconsistency in the same population evaluated in different environments. It must be clarified if this is due to genotype x environment interaction or considerations of statistics if the value of QTLs for marker-assisted breeding is to be estimated. A modified split-plot design was used where a main plot corresponded to a separate experiment. The main plot factor had four treatments (environments), which were completely randomized among eight trials, so that each treatment was replicated twice. The sub-plot factor consisted of 168 recombinant inbreed lines of the Bala x Azucena rice mapping population, randomly allocated to the seven soil-filled boxes. The aim of the trial was to quantify QTL x environment interaction. The treatments were chosen to alter partitioning to roots; consisting of a control treatment (high-soil nitrogen, high light and high-water content) and further treatments where light, soil nitrogen or soil water was reduced singly. After 4 weeks growth, maximum root length (MRL), maximum root thickness, root mass below 50 cm, total plant dry mass (%), root mass and shoot length were measured. The treatments affected plant growth as predicted; low nitrogen and drought increased relative root partitioning, low-light decreased it. The parental varieties Bala and Azucena differed significantly for all traits. Broad-sense heritability of most traits was high (57-86%). Variation due to treatment was the most important influence on the variance, while genotype was next. Genotype x environment interaction was detected for all traits except MRL, although the proportion of variation due to this interaction was generally small. It is concluded that genotype x environment interaction is present but less important than genotypic variation. A companion paper presents QTL x environment analysis of data.

Chromosome Mapping↗

Comparing internal models of the dynamics of the visual environment.

It is well known that the human postural control system responds to motion of the visual scene, but the implicit assumptions it makes about the visual environment and what quantities, if any, it estimates about the visual environment are unknown. This study compares the behavior of four models of the human postural control system to experimental data. Three include internal models that estimate the state of the visual environment, implicitly assuming its dynamics to be that of a linear stochastic process (respectively, a random walk, a general first-order process, and a general second-order process). In each case, all of the coefficients that describe the process are estimated by an adaptive scheme based on maximum likelihood. The fourth model does not estimate the state of the visual environment. It adjusts sensory weights to minimize the mean square of the control signal without making any specific assumptions about the dynamic properties of the environmental motion. We find that both having an internal model of the visual environment and its type make a significant difference in how the postural system responds to motion of the visual scene. Notably, the second-order process model outperforms the human postural system in its response to sinusoidal stimulation. Specifically, the second-order process model can correctly identify the frequency of the stimulus and completely compensate so that the motion of the visual scene has no effect on sway. In this case the postural control system extracts the same information from the visual modality as it does when the visual scene is stationary. The fourth model that does not simulate the motion of the visual environment is the only one that reproduces the experimentally observed result that, across different frequencies of sinusoidal stimulation, the gain with respect to the stimulus drops as the amplitude of the stimulus increases but the phase remains roughly constant. Our results suggest that the human postural control system does not estimate the state of the visual environment to respond to sinusoidal stimuli.

Algorithms↗

Non-steady-state equilibrium model for the preliminary prediction of the fate of chemicals in the environment.

Prediction of the fate of chemicals in the environment is essential to the assessment of the potential hazard of chemicals. The fate of a chemical in the environment depends mainly upon (1) transfer processes between environmental compartments due to physicochemical properties, (2) transformation processes in each compartment, and (3) characteristics of the environment. Many equilibrium or kinetic models have been proposed to predict the fate of chemicals in the environment. Though kinetic models are useful in predicting the concentration-time profile of a chemical at the non-steady state, they are rather complicated. In this work is proposed a simple and useful equilibrium model for prediction of the mass and concentration distribution fraction, mean residence time, and concentration-time profile of a chemical released into the environment, an advantage of our model. For the validation of this model, the results were compared with data from Neely's pond experiment and field data monitored by the Japanese Environment Agency. The results show that the equilibrium model is valuable for preliminary prediction of the fate of chemicals that are priority chemicals for hazard assessment in the environment.

Chemical Phenomena↗

Environment, obesity, and cardiovascular disease risk in low-income women.

BACKGROUND: Financially disadvantaged populations are more likely to live in communities that do not support healthy choices. This paper investigates whether certain characteristics of the built environment are associated with obesity or coronary heart disease (CHD) risk among uninsured low-income women. METHODS: Using a sample of 2001-2002 data from 2692 women enrolled in the WISEWOMAN program of the Centers for Disease Control and Prevention, the study team performed regression analysis (conducted in January-April 2005) to estimate body mass index (BMI) and the log of 10-year CHD risk as a function of the built environment and socioecologic measures. RESULTS: For women living in an environment of maximum mixed land use (i.e., an environment more conducive to healthy living), BMI was lower by 2.60 kg/m2 and CHD risk was lower by 20% than for women living in single-use uniform environments (i.e., environments less conducive to healthy living). An additional fitness facility per 1000 residents was associated with BMI and CHD risk that were lower by 1.39 kg/m2 and 15.1%, respectively. Crime was positively associated with BMI and CHD risk, whereas neighborhood affluence was negatively associated. Living in more racially segregated areas was negatively associated with CHD risk among black, Hispanic, and Asian women and positively associated with CHD risk among American Indian women. CONCLUSIONS: The built environment and socioecologic characteristics of financially disadvantaged women were associated with BMI and CHD risk. More research is needed to understand the effects of racial segregation or acculturation on health for specific subpopulations.

Adult↗

A simultaneous analysis of neighbourhood and childhood socio-economic environment with self-assessed health and health-related behaviours.

Childhood socio-economic environment and neighbourhood socio-economic environment later in life are closely related. However, few studies have considered their effects simultaneously. Using cross-sectional data of approximately 8000 respondents in 86 neighbourhoods in the city of Eindhoven, The Netherlands, we study associations of both determinants with self-assessed health, smoking, alcohol consumption and overweight. Growing up in a low socio-economic environment increased the probability to live a more deprived neighbourhood in adulthood. Controlling for individual socio-economic characteristics, both childhood and neighbourhood socio-economic environment were related to smoking and overweight, but not with excessive alcohol consumption. Associations between childhood socio-economic environment and smoking and overweight are still substantial after controlling for neighbourhood socio-economic environment. Similarly, neighbourhood inequalities in smoking and overweight remain substantial after controlling for childhood socio-economic environment.

Adult↗

Influence of in-tunnel environment to in-bus air quality and thermal condition in Hong Kong.

In this study, the potential exposure of bus commuters to significant air parameters (CO(2), CO and RSP) and thermal environment (air temperature and relative humidity) when buses traveled through tunnels in Hong Kong was investigated. It was found that air-conditioned buses provided a better commuting environment than non-air-conditioned buses. The blate increasing trend was found on air-conditioned buses as the in-bus air parameters concentration levels rose slowly throughout the traveling process. In contrast, the in-bus environment varied rapidly on non-air-conditioned buses as it depended on the out-bus environment. The measured in-bus CO concentration was 2.9 ppm on air-conditioned buses, while it was 4.6 ppm (even reaching the highest level at 12.0 ppm) on non-air-conditioned buses. Considering the in-bus thermal environment, air-conditioned buses provided thermally comfortable cabins (about 24 degrees C and 59% of relative humidity). However, on non-air-conditioned buses, the thermal environment varied with the out-bus environment. The mean in-bus air temperature was about 34 degrees C and 66% of relative humidity, and the in-bus air temperature varied between 29 and 38 degrees C. Also, the lower-deck to upper-deck air parameters concentration ratios indicated that the vertical dispersion of air pollutants in tunnels influenced non-air-conditioned buses as higher air parameters concentration levels were obtained on the lower-deck cabins.

Air Conditioning↗

A virtual reality environment for evaluation of a daily living skill in brain injury rehabilitation: reliability and validity.

OBJECTIVE: To establish the stability and validity of information collected in a virtual reality environment from persons with traumatic brain injury (TBI). DESIGN: Prospective correlation design to examine 3-week test-retest results for equivalence reliability between computer-simulated and natural environments. SETTING: A residential rehabilitation center for brain injury. PARTICIPANTS: Fifty-four consecutive patients with TBI who received comprehensive rehabilitation services and who were at different stages of recovery. INTERVENTION: An immersive virtual kitchen was developed in which a meal preparation task involving multiple steps was performed. The subjects completed meal preparation both in a virtual reality kitchen and an actual kitchen twice over a 3-week period. MAIN OUTCOME MEASURES: Time and errors on task completion using virtual reality assessment, actual kitchen performance (analogous to the virtual reality environment), occupational therapy (OT) evaluation, and neuropsychologic tests. RESULTS: The stability of performance using the simulated virtual environment was estimated with intraclass correlation coefficients (ICCs). The ICC value for total performance, based on all steps involved in the meal preparation task, was.76 (P<.01). The construct validity of the simulated environment was examined by correlating performance in the virtual environment with that in the actual kitchen (r=.63, P<.01), the OT evaluation (r=.30, P=.05 for meal preparation; r=.40, P=.01 for cognitive subskills), and neuropsychologic tests (r=.56, P<.01 for the full-scale intelligence quotient [IQ]; r=.40, P<.01 for the verbal IQ; r=.56, P<.01 for the performance IQ). Finally, a multiple regression analysis revealed that the virtual reality environment test was a good predictor for the actual assessment kitchen (beta=.35, P=.01). CONCLUSION: The virtual reality system showed adequate reliability and validity as a method of assessment in persons with brain injury.

Adolescent↗

Androgen inhibits neurotransmitter turnover in the medial prefrontal cortex of the rat following exposure to a novel environment.

Previous studies have demonstrated that gonadal steroid hormones affect the neuroendocrine response to a novel environment and other stressors. Introduction to a novel environment also increases neurotransmitter turnover in the medial prefrontal cortex (MPFC). In this study, we examined the possibility that gonadal steroid hormones could similarly modulate the neurotransmitter response to a novel environment in the MPFC of the male rat. Male Fischer 344 rats at 3 months of age were gonadectomized (GDX'd) and implanted with Silastic capsules containing dihydrotestosterone propionate (DHTP, a non-aromatizable form of androgen), 17 beta-estradiol (E), or placebo. Control animals were left intact. Each of these groups was further divided into a group introduced to a novel environment or a home cage control group. Animals exposed to a novel environment were killed after spending 20 min in a novel open field, whereas control animals were killed immediately upon removal from their home cage. Using high performance liquid chromatography, the MPFC was assayed for tissue levels of dopamine (DA) and its metabolites, 3,4-dihydroxyphenylalanine (DOPAC) and homovanillic acid (HVA); norepinephrine (NE) and its metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG); or serotonin (5-HT) and its metabolite 5-hydroxyindole acetic acid (5-HIAA). The introduction to a novel environment caused significant increases in turnover of all three neurochemicals examined as estimated by metabolite/precursor ratios. These increases were characterized by increases in DOPAC, HVA, MHPG and 5-HIAA coupled with decreases in DA, NE and 5-HT. There was no effect of GDX on neurotransmitter turnover, however, treatment of GDX animals with DHTP prevented the open field induced increase in DOPAC/DA, MHPG/NE, and 5-HIAA/5-HT ratio. Treatment of GDX animals with estrogen had the opposite effect of DHTP, DOPAC/DA and MHPG/NE ratios increased to a greater level following the introduction to a novel environment than in GDX or intact animals. Examination of behavior in the open field showed significant decreases in activity in the DHTP-treated group but not in any other behavioral parameter (rears, nose pokes). Since the non-aromatizable androgen, DHTP, is presumably acting via androgen receptors, and E is presumably acting via estrogen receptors, these data suggest that, in the MPFC of male rats, androgen and estrogen receptors act in an opposing fashion to modify neurotransmitter turnover. This suggests that local changes in the relative levels of androgen and estrogen can have profound effects on the neurobiological response of the medial prefrontal cortex to stimuli.

3,4-Dihydroxyphenylacetic Acid↗

Occurrence, fate and effects of pharmaceutical substances in the environment--a review.

Medical substances (pharmaceuticals) are a group of substances that until recently have been exposed to the environment with very little attention. The reason why they may be interesting as environmental micropollutants, is that medical substances are developed with the intention of performing a biological effect. Especially antibiotics used as growth promoters, as feed additives in fish farms are anticipated to end up in the environment. Very little is known about the exposure routes of the medical substances to the environment. Only few investigations have reported findings of medical substances in other field samples than sediment or treated waste water samples. Several substances seem to be persistent in the environment. This paper outlines the different anticipated exposure routes to the environment, summarises the legislation on the subject and gives an outline of present knowledge of occurrence, fate and effect on both the aquatic and terrestrial environments of medical substances. Present knowledge does not reveal if regular therapeutic use may be the source of a substance carried by sewage effluent into the aquatic system, even though clofibrate, a lipid lowering agent, has been identified in ground and tap water samples from Berlin. Further research would be necessary to assess the environmental risk involved in exposing medical substances and metabolites to the environment.

Animals↗

Health risk assessment of fungi in home environments.

LEARNING OBJECTIVES: Reading this article will enable the readers to recognize the public health importance of fungi in the home environment. In view of the recognized impact of fungi on human health, the large population being exposed to fungi, and the large population risk for developing allergic diseases, there is a need to establish guidelines for allowable exposure to fungi based on a health risk assessment. The aim of this study was to evaluate the status of the data on the relationship between exposure to fungi in the home environment and allergic health effects with respect to the development of such guidelines. DATA SOURCES: The past 10 years of peer-reviewed literature focused on the relationships between respiratory disease and exposure to fungi in indoor environments was examined, Indexing terms included mold, fungi, allergy, asthma, and indoor environment, among others. Each study was evaluated on the following criteria: aim and design of the study, methods for assessing exposure and health effects, and data analysis. STUDY SELECTION: Nine population based studies were identified that examined the relationship between allergy and the presence of fungi in the home environment. These studies included quantitative measures of fungal presence in either air or dust. RESULTS: One or more positive associations were found between fungal levels and health outcomes in seven of the nine cross-sectional studies identified. CONCLUSIONS: Despite these positive associations it remains impossible to set guidelines for fungi in home environments based on health risk assessment. This is in part because of the cross-sectional study designs, and inconsistency and inadequate validation of the measures used to evaluate exposure and health effects. Future research designed to generate data that can be used for the development of health risk assessment based guidelines for fungi in home environments should focus on susceptible populations, and use measures that accurately represent exposure and adverse health effects.

Air Microbiology↗

Indoor dose conversion coefficients for radon progeny for different ambient environments.

Inhaled progeny of 222Rn (radon progeny) are the most important source of irradiation of the human respiratory tract. Their attachment to atmospheric aerosols follows a well-established relationship between the activity size distribution (ASD) and the number size distribution. Recent studies have shown that indoor aerosols are derived primarily from outdoor sources, so it is pertinent to study the effects of different ambient environments on the indoor radon dose (in terms of the dose conversion coefficient or DCC, in units of mSv WLM-1). Commonly encountered ambient aerosols were studied here, which included the traffic-, urban-, and marine-influenced aerosols. The ASDs of attached radon progeny for all three studied ambient environments were well-represented by normal distributions. From these ASDs, the DCCs were calculated using the ICRP66 model and the scaled Yeh-Schum model. All other employed parameters were adopted from original references or authoritative reports. The DCCs for a nominal home calculated using the James model and the Yeh-Schum model were 12 and 8 mSv WLM-1, respectively. The DCCs were largest for urban-influenced ambient environments and smallest for marine-influenced ambient environments, and those for traffic-influenced ambient environments were close to that for a nominal home. If we adopt the stochastic model, the probability of contracting radon-induced lung cancer by a person living with a marine-influenced ambient environment will be half that of a person living with an urban-influenced ambient environment.

Aerosols↗

Molecular dynamics simulations of angiotensin II in aqueous and dimethyl sulfoxide environments.

Angiotensin II (Ang II) is an octapeptidic hormone, which plays an important role in the mechanisms of blood pressure control. In this work, extensive molecular dynamics (MD) simulations have been carried out on this peptide, both in aqueous and in dimethyl sulfoxide (DMSO) environments. Experimentally proposed models for the structure of angiotensin II in both environments are not consensual and the results obtained have provided some further insight about the structural properties of this hormone. In these simulations, the N-terminus of Ang II in the aqueous environment has been associated with a considerable larger flexibility than the correspondent C-terminus, but this was not found in the case of the DMSO environment. This is consistent with the assumption that the biological activity of Ang II is associated with its C-terminal residues embedded in a hydrophobic environment of its AT1 receptor. Other features detected in DMSO environment were an H(His6 imidazole)-O(Phe8 carboxylate) hydrogen bond and a salt-bridge structure involving the Asp1 and Arg2 side chains. An additional important conformational feature is the spatial proximity between Tyr4 and His6 in both water and DMSO environments. This molecular feature may trigger the interest for the synthetic chemists to apply rational design for the synthesis of novel AT1 antagonists.

Angiotensin II↗

Childhood farm environment and asthma and sensitization in young adulthood.

BACKGROUND: Farm environment in childhood may protect against sensitization, allergic rhinitis, and asthma. METHODS: Subjects were obtained from 10 667 Finnish first-year university students who responded to a questionnaire survey on IgE-mediated diseases. Two random samples were selected from 1631 respondents in Turku: subjects with asthma or wheezing, and subjects without asthmatic symptoms. A total of 296 subjects (72%) participated. Skin prick tests (SPT), measurements of IgE-antibodies, methacholine challenge, and bronchodilation tests were performed. Weighted occurrence of current asthma and sensitization among students from "childhood farm" and "childhood nonfarm" environments were analyzed. RESULTS: Current asthma was found in 3.1% of subjects with childhood farm environment, and in 12.4% with nonfarm environment (odds ratio (OR) 0.22; 95% confidence interval (CI) 0.07-0.70). There were fewer positive SPT to birch (8.3 vs. 24.2%, OR 0.28, 95% CI 0.07-1.15) and timothy pollen (12.6 vs. 30.3%, OR 0.33, 95% CI 0.09-1.20) among subjects with childhood farm environment, but more sensitization to house-dust mite (22.0 vs. 4.9%, OR 5.43, 95% CI 1.60-18.46). Sensitization to cat (RAST class >/= 3) was less common in subjects with farm compared to nonfarm environments in childhood (1.5 vs. 13.1%; OR 0.10, 95% CI 0.02-0.47). CONCLUSIONS: Farm environment in childhood protects against adult asthma and sensitization-especially to cat-the most important asthma related allergen. In contrast, sensitization to house-dust mite was more common in farming subjects.

Adolescent↗