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Studies have reported the effect of body weight in early childhood on asthma. However, the effect of growth patterns during school age on asthma and rhinitis has yet to be explored. We sought to investigate whether various growth patterns predict incident asthma and rhinitis.We conducted a nationwide longitudinal study (Taiwan Children Health Study) in 14 Taiwanese communities. Body mass index (BMI) z-scores of 4422 children aged 6–11 years were collected annually and distinct growth trajectory classes were identified using a latent generalised mixture model. Pulmonary function and exhaled nitric oxide fraction (FeNO) levels were also measured. Whether different growth trajectory classes predict incident asthma and rhinitis at age 12, 15 and 18 years was determined using a discrete time hazard model.Four growth trajectory classes were identified. Persistently overweight children exhibited significantly increased risks of asthma and rhinitis at age 12 years. Furthermore, being persistently overweight had a long-term effect on incident asthma (hazard ratio 2.47, 95% CI 1.18–5.12) and rhinitis (hazard ratio 1.44, 95% CI 1.12–1.84) in adolescence and early adulthood. Children in high BMI classes exhibited significantly lower pulmonary functions compared with normal growth children. FeNO levels were lower in children in the high BMI classes and higher in children showing declining obesity compared with normal growth children.Persistently overweight children exhibited incident asthma and rhinitis in adolescence and early adulthood.

Background and aims: Ambient traffic-related air pollutants, such as nitrogen dioxide (NO2), have shown adverse effects on respiratory health in children. However, few studies showed the interactiv...

We explored the relationship among sociodemographic, behavioural, household environmental and perinatal factors, and risks of childhood overweight and obesity in Taiwan.A total of 7930 children aged 9 to 14 years were recruited from 14 randomly selected Taiwanese communities in 2007 and 2010. Height and weight were measured using standard protocols during school visits. Questionnaires that contained children's family information, birth conditions, exercise habits and household environmental factors were answered by the parents. Associations between risk factors and childhood overweight and obesity were estimated through odds ratio and 95% confidence interval from mixed models.In this cohort, 32.3% of the children were overweight and 17.5% were obese. Male gender, high birthweight, exposure to in utero maternal smoking and current exposure to household environmental tobacco smoke (stronger effect of maternal than paternal smoking) were positively associated with childhood overweight/obesity. In contrast, higher parental education level, number of siblings, active exercise habits and taking vitamins were associated with reduced risks of childhood obesity. Birthweight revealed a J-shaped relationship with the probability of childhood overweight/obesity.This study uncovers several modifiable risk factors for childhood overweight and obesity, and parents are encouraged to provide an anti-obesity environment such as quitting smoking, controlling birthweight of child during pregnancy and building up exercise habits.

Asthma, which is characterized by reversible airway obstruction and inflammation, is the most frequent chronic disease in children. Recent global studies showed, although the rising trends in occurrence of allergic diseases in children appear to have leveled off or even reversed in many developed countries, while in many developing countries, the increase in prevalence has only recently started (Asher et al. 2006; Bjorksten et al. 2008; Pearce et al. 2007). These findings indicate that the global burden of asthma is continuing to be rising with the global prevalence differences lessening (Pearce et al. 2007). It has been suggested that this increase can not be explained by genetic factors and improvements in diagnostic methods alone. Comparative studies of the population of the same ethnic background living in different environments revealed important environmental risk factors for asthma, especially for ambient air pollution, which may play an important role in the development of asthma symptoms (Asher et al. 2010; Berhane et al. 2011; Samoli et al. 2011; McConnell et al. 2010). A systematic review concluded that, although weather, pollen, and environmental tobacco smoke (ETS) are important risk factors for asthma, each has been found to act independently of air pollution, and thus they do not explain the association between air pollution and asthma (Leikauf 2002).

BackgroundThere are limited studies on the role of interaction between exposure to ambient air pollution and glutathione-S-transferase (GST) P1 on the risk of asthma/wheezing among children, which provided suggestive, but inconclusive results.MethodsTo assess the joint effect of air pollutants and GSTP1 on asthma/wheezing, we conducted a nationwide cross-sectional study of 3,825 children in Taiwan Children Health Study. The studied determinants were three GSTP1 Ile105Val (rs 1695) genotypes (Ile-Ile; Ile-Val and Val-Val) and expoure to ambient air pollutants. We used routine air-pollution monitoring data for ozone (O(3)) and particles with an aerodynamic diameter of 2.5 µm or less (PM(2.5)). The effect estimates were presented as odds ratios (ORs) per interquartile changes for PM(2.5) and O(3).FindingsIn a two-stage hierarchical model adjusting for confounding, the risk of asthma was negatively associated with PM(2.5) (adjusted odds ratio (OR) 0.60; 95% confidence interval (CI) 0.45, 0.82) and O(3) (OR 0.74; 95% CI 0.60, 0.90) among Ile105 homozygotes, but positively associated with PM(2.5) (OR 1.52; 95% CI 1.01, 2.27) and O(3) (OR 1.19; 95% CI 0.91, 1.57) among those with at least one val105 allele (interaction p value = 0.001 and 0.03, respectively). A similar tendency of effect modification between PM(2.5) and O(3) and GSTP1 on wheezing was found.ConclusionChildren who carried Ile105 variant allele and exposed to PM(2.5) and O(3) may be less likely to occurrence of asthma/wheezing.

BackgroundPrevious studies revealed that reduction of airway caliber in infancy might increase the risks for wheezing and asthma. However, the evidence for the predictive effects of pulmonary function on respiratory health in children was still inconsistent.MethodsWe conducted a population-based prospective cohort study among children in 14 Taiwanese communities. There were 3,160 children completed pulmonary function tests in 2007 and follow-up questionnaire in 2009. Poisson regression models were performed to estimate the effect of pulmonary function on the development of bronchitis and asthma.ResultsAfter adjustment for potential confounders, pulmonary function indices consistently showed protective effects on respiratory diseases in children. The incidence rate ratios of bronchitis and asthma were 0.86 (95% CI 0.79-0.95) and 0.91 (95% CI 0.82-0.99) for forced expiratory volume in 1 second (FEV₁). Similar adverse effects of maximal mid-expiratory flow (MMEF) were also observed on bronchitis (RR = 0.73, 95% CI 0.67-0.81) and asthma (RR = 0.85, 95% CI 0.77-0.93). We found significant decreasing trends in categorized FEV₁ (p for trend = 0.02) and categories of MMEF (p for trend = 0.01) for incident bronchitis. Significant modification effects of traffic-related air pollution were noted for FEV₁ and MMEF on bronchitis and also for MMEF on asthma.ConclusionsChildren with high pulmonary function would have lower risks on the development of bronchitis and asthma. The protective effect of high pulmonary function would be modified by traffic-related air pollution exposure.

Background Dampness in the home is a strong risk factor for respiratory symptoms and constitutes a significant public health issue in subtropical areas. However, little is known about the effects of dampness and genetic polymorphisms on asthma. Methods In 2007, 6078 schoolchildren were evaluated using a standard questionnaire with regard to information about respiratory symptoms and environmental exposure. Multiple logistic regression analyses were performed to assess the effects of home dampness and beta-2-adrenergic receptor (ADRB2) gene polymorphisms on the prevalence of asthma and selected indicators of severity of asthma. Results The frequency of mildewy odor, the number of walls with water stamp, and the duration of water damage were all associated with being awakened at night due to wheezing. However, no other clear-cut associations were found for any of the other indicators of asthma. Children exposed to mildewy odor with ADRB2 Arg/Arg genotype were associated with being awakened at night due to wheezing (OR=1.95, 95% CI, 1.14–3.36), compared to those without exposure and with the ADRB2 Gly allele. ADRB2 Arg16Gly showed a significant interactive effect with home dampness on being awakened at night due to wheezing and current wheezing, but no significant effect on active asthma and medication use. Frequency and degree of home dampness were also associated with the prevalence of asthma and selected indicators of severity of asthma, in an exposure–response manner among children with ADRB2 Arg/Arg genotype. Conclusions Home dampness prevention is one of the important steps of asthma control, especially in children carrying ADRB2 Arg/Arg genotypes.

Barnett expresses concerns about a potential bias in our article (Hwang et al. 2011) related to use of a fixed study period based on the date of delivery: on average a shorter duration of gestation among stillbirths compared to live births in combination with seasonal variation of exposure. We acknowledge the complexity of assessing effects of exposure with seasonal variation on the risk of stillbirth and thank Barnett for his suggestion to avoid a possible bias, which he with his colleagues illustrated through simulations of a retrospective cohort study (Strand et al. 2011). We reanalyzed the data, excluding case and control subjects following Barnett’s suggestion to quantify the “fixed cohort bias.” This led to loss of approximately 4.7% (4,480/102,575) of the subjects. The point estimates were similar with those from the original analyses, but some confidence intervals became wider (Table 1). This shows that the role of the fixed cohort bias was minimal in our study. Table 1 Adjusted ORs (95% CIs) for stillbirth by average pollutant concentrations, by trimester and for the whole pregnancy (single pollutant models), following Barnett’s suggestion to address the “fixed cohort bias.”

Background and Aims:Environmental tobacco smoke (ETS) is an important exposure of indoor air, and may increase the risk of respiratory disease in children. The level of household ETS exposure may b...

Background and Aims: Evidence has shown that climate may contribute to different prevalence of asthma in different geographic areas. In subtropical area, indoor dampness is a risk factor for respir...

Our aim is to explore (1) whether gestational medication use, mode of delivery, and early postnatal exposure correlate with childhood asthma, (2) the dose responsiveness of such exposure, and (3) their links to early- and late-onset asthma. We conducted a matched case-control study based on the Taiwan Children Health Study, which was a nationwide survey that recruited 12-to-14-year-old school children in 14 communities. 579 mothers of the participants were interviewed by telephone. Exclusive breastfeeding protected children from asthma. Notably, childhood asthma was significantly associated with maternal medication use during pregnancy, vacuum use during vaginal delivery, recurrent respiratory tract infections, hospitalization, main caregiver cared for other children, and early daycare attendance. Exposure to these factors led to dose responsiveness in relationships to asthma. Most of the exposures revealed a greater impact on early-onset asthma, except for vacuum use and daycare attendance.

To assess the prevalence, awareness, treatment, and control of hypertension and their associated factors in an urban Chinese population.A cross-sectional study was conducted in three cities in northeast China from 2009 to 2010, using a multistage cluster sampling method to select a representative sample. A total of 25 196 adults, aged 18-74 years, were examined in 33 communities. Hypertension was defined as a mean SBP of at least 140 mmHg, DBP at least 90 mmHg, and/or use of antihypertensive medications.Overall, the prevalence of hypertension was 28.7% for urban residents, and 39.1% for middle-aged and elderly residents (aged ≥35 years). Among all the hypertensive patients examined in the study (n = 7237), 42.9% were aware of their condition, 28.2% were receiving treatment, and only 3.7% had their blood pressure adequately controlled. Female hypertensive patients had more effectively controlled blood pressure than their male counterparts. Among the study participants, 37.9% did not think that high blood pressure would endanger their lives. Among hypertensive patients aware of their conditions, the primary reason for not taking antihypertensive medication was a lack of money (34.8%). Age, sex, education, occupation, income, body mass, waist circumference, and family hypertension history significantly correlated with the prevalence of hypertension.Hypertension is highly prevalent in the urban population of China, and the effects of being overweight/obesity on hypertension were much larger than any other examined factors. The percentage of hypertensive patients aware of their condition, receiving proper treatment, and keeping their hypertension under control is unacceptably low.

BackgroundThe relationship between ambient air pollution exposure and mortality of cardiovascular and cerebrovascular diseases in human is controversial, and there is little information about how exposures to ambient air pollution contribution to the mortality of cardiovascular and cerebrovascular diseases among Chinese. The aim of the present study was to examine whether exposure to ambient-air pollution increases the risk for cardiovascular and cerebrovascular disease.Methodology/principal findingsWe conducted a retrospective cohort study among humans to examine the association between compound-air pollutants [particulate matter Conclusion/significanceLong-term exposure to ambient air pollution is associated with the death of cardiovascular and cerebrovascular diseases among Chinese populations.

The first successfully implemented real-time Mandarin dictation machine, which recognizes Mandarin speech with very large vocabulary and almost unlimited texts for the input of Chinese characters into computers, is described. The machine is speaker-dependent, and the input speech is in the form of sequences of isolated syllables. The machine can be decomposed into two subsystems. The first subsystem recognizes the syllables using hidden Markov models. Because every syllable can represent many different homonym characters and form different multisyllabic words with syllables on its right or left, the second subsystem is needed to identify the exact characters from the syllables and correct the errors in syllable recognition. The real-time implementation is on an IBM PC/AT, connected to three sets of specially designed hardware boards on which seven TMS 320C25 chips operate in parallel. The preliminary test results indicate that it takes only about 0.45 s to dictate a syllable (or character) with an accuracy on the order of 90%. >

The recognition of a total of 408 very confusing Mandarin syllables is very difficult because this vocabulary consists of 38 confusing sets, each of which can have as many as 19 syllables. The recognition of these 408 syllables becomes even more difficult when only very limited training data are available. A special direct-concatenation approach for training hidden Markov models (HMMs) to recognize these syllables with very limited training data is developed in which each syllable is divided into INITIAL and FINAL parts and 408 right-context-dependent INITIAL HMMs and 38 left-context-independent FINAL HMMs are separately trained and the transition region carefully taken account of, and then these INITIAL and FINAL HMMs are directly concatenated to form syllable recognition. Experimental results show that this approach can utilize the very limited training data most efficiently and provide significant improvements in recognition performance. Although the results are obtained for Mandarin syllables, the approach is believed to be equally helpful for the recognition of other confusing vocabularies. >

Incense burning is a popular practice in many family homes and temples. However, little is known about the effects of indoor incense burning and genetic polymorphisms on asthma. This study evaluated the effects of indoor incense burning and glutathione S-transferase (GST) genetic polymorphisms on asthma and wheeze. In 2007, 3,764 seventh-grade schoolchildren (mean±sd age 12.42±0.65 yrs) were evaluated using a standard questionnaire for information about respiratory symptoms and environmental exposures. Multiple logistic regressions were performed to assess the association between GST polymorphisms and incense burning frequency on asthma and wheeze, after adjusting for potential confounders. The frequency of incense burning at home was associated with increased risk of current asthma (p=0.05), medication use (p=0.03) and exercise wheeze (p=0.001). GST1 (GSTT1) null genotypes were associated with current asthma (OR 1.43, 95% CI 1.00-2.04) and medication use (OR 1.46, 95% CI 1.01-2.22). GSTT1 showed a significant interactive effect with incense burning on current asthma, current wheeze and nocturnal wheeze. The frequency of incense burning was associated with increased risk of current asthma, medication use, lifetime wheeze, nocturnal wheeze and exercise wheeze in an exposure-response manner among children with GSTT1 null genotype (p

BACKGROUND Diabetes mellitus (DM) and hypertension (HT) frequently coexist. Increased central aortic pressures indexes are associated with HT; however, possible associations of these indexes with future development of DM have never been studied in HT. METHODS We recruited 178 patients with uncomplicated nondiabetic HT in this study. Baseline glucose, insulin, lipid profiles, and central aortic pressure indexes obtained using applanation tonometry were measured at the beginning of the study. Patients were followed for new-onset DM. RESULTS After a mean follow-up period of 31 ± 12 months, 22 patients (12.4%) developed new-onset DM. In multivariate regression analyses adjusted for age, sex, and mean blood pressure (BP) in model 1, we found that central systolic BP (CSBP; hazard ratio 1.24, 95% CI 1.10-1.41, P < 0.001), and augmentation index (AIx) corrected at heart rate 75/min (AIx(75); hazard ratio 1.58, 95% CI 1.11-1.58, P < 0.05) were independent predictors for new-onset DM. After adjustment for age, sex, mean BP, glucose concentration, and β-blocker use in model 2, we found that CSBP (hazard ratio 1.36, 95% CI 1.19-1.55, P < 0.001) and AIx(75) (hazard ratio 1.71, 95% CI 1.16-2.52, P < 0.01) were independent predictors for new-onset DM. CONCLUSIONS CSBP and AIx(75) were independent factors for future DM in essential hypertensive patients. Increased central pressure indexes were associated with risk of DM in essential hypertension.

Summary Objectives To investigate the effectiveness of nationwide periodic health examinations in promoting early treatment of hypertension, diabetes and hyperlipidemia in adults aged ≥40 years. Study design Seven-year, retrospective, cohort study. Methods Based on a large and representative claims dataset in Taiwan, cohort analysis was undertaken among three disease-free cohorts for hypertension, diabetes and hyperlipidemia ( n = 26,661, 29,872 and 30,712 subjects, respectively) in 2000. Each cohort was observed from January 2001 to December 2007. Logistic regression, Cox proportional hazards analysis and the extended Cox model with counting process were employed in data analysis. Covariates such as age, gender, level of premium, beneficiary category, comorbidities and geographic factors were adjusted at baseline. Results For the hypertension, diabetes and hyperlipidemia cohorts, those who had ever used the preventive service between 1998 and 2000 had higher probabilities of being treated as new patients for these target diseases; the hazard ratios were 1.65, 1.32 and 1.57, respectively. Using the extended Cox model, associations for use of each service with treatment within a 1-year follow-up period between 2001 and 2007 were 1.68, 2.41 and 3.48. Conclusions In adults who were initially disease-free, those who used the preventive service had higher probabilities of early treatment of these target diseases. These findings indicate the effectiveness of nationwide periodic health examinations.

Background Although studies show that maternal smoking during pregnancy increases the risks of respiratory outcomes in childhood, evidence concerning the effects of household environmental tobacco smoke (ETS) exposure remains inconsistent. Methods We conducted a population-based study comprised of 5,019 seventh and eighth-grade children in 14 Taiwanese communities. Questionnaire responses by parents were used to ascertain children's exposure and disease status. Logistic regression models were fitted to estimate the effects of ETS exposures on the prevalence of asthma, wheeze, and bronchitic symptoms. Results The lifetime prevalence of wheeze was 11.6% and physician-diagnosed asthma was 7.5% in our population. After adjustment for potential confounders, in utero exposure showed the strongest effect on all respiratory outcomes. Current household ETS exposure was significantly associated with increased prevalence of active asthma, ever wheeze, wheeze with nighttime awakening, and bronchitis. Maternal smoking was associated with the increased prevalence of a wide range of wheeze subcategories, serious asthma, and chronic cough, but paternal smoking had no significant effects. Although maternal smoking alone and paternal smoking alone were not independently associated with respiratory outcomes, joint exposure appeared to increase the effects. Furthermore, joint exposure to parental smoking showed a significant effect on early-onset asthma (OR, 2.01; 95% CI, 1.00-4.02), but did not show a significant effect on late-onset asthma (OR, 1.17; 95% CI, 0.36-3.87). Conclusion We concluded that prenatal and household ETS exposure had significant adverse effects on respiratory health in Taiwanese children.

Analysis of short-term heart rate variability (HRV) may provide useful information about autonomic nervous control of heart rate recovery. We studied 495 individuals (273 men), age range 19–85 years, submitted to treadmill exercise tests and short-term HRV evaluations over time (standard deviation of the normal-to-normal interval [SDNN], the square root of the mean squared differences of successive normal-to-normal intervals [RMSSD], the number of interval differences of successive normal-to-normal intervals greater than 50 ms [NN50 count], the proportion derived by dividing NN50 count by the total number of normal-to-normal intervals [pNN50]) and frequency (low-frequency power [LF], high-frequency power [HF], total power) domains. Among 495 patients, 106 patients (68 men) were elderly (age ≥ 65 years). Male gender and hypertension were significantly higher in elderly patients. The young patients had higher HRR after exercise. HRR at 4 min (54 ± 13 vs 60 ± 12 beats/min; P = 0.003) was the most significant predictor for positive exercise test result. In the young group, both time domain measures (SDNN: correlation coefficient 0.34, P < 0.001; RMSSD: correlation coefficient 0.37, P < 0.001) and frequency domain measures (LF: correlation coefficient 0.21, P < 0.001; HF: correlation coefficient 0.13, P = 0.01; total power: correlation coefficient 0.22, P < 0.001) were significantly associated with HRR at 4 min. HRR at 4 min was significantly associated with short-term HRV of time and frequency domains in young individuals, but not elderly ones, receiving treadmill exercise test.

Background: Tumor necrosis factor (TNF)-α has a recognized role in respiratory pathophysiology. One genetic variant (G-308A) in the promoter region affecting the expression of this cytokine may contribute to airway inflammatory diseases, but the studies on bronchitic symptoms were still inconclusive. Because ozone produces oxidative stress, increased airway TNF, and inflammation, the associations of the TNF-308 polymorphism with bronchitic symptoms may vary by ambient ozone exposure. Methods: We studied associations of TNF-308 genotype with bronchitic symptoms among asthmatic children in Children’s Health Study. The association of TNF G-308A polymorphism with bronchitic symptoms was investigated and we also determined whether the associations vary with ambient ozone exposure. Results: Asthmatic children with TNF-308 GG genotype had a significantly reduced risk of bronchitic symptoms with low-ozone exposure (adjusted OR: 0.53; 95% CI: 0.31–0.91). The risk was not reduced in children living in high-ozone communities (adjusted OR: 1.42; 95% CI: 0.75–2.70). This difference in genotypic effects between low- and high-ozone environments was statistically significant among asthmatics (P for interaction = 0.01), but insignificant among nonasthmatic children. Conclusion: Our findings suggest a role of gene–environmental interactions on the occurrence of bronchitic symptoms among children with asthma.

Summary Background Parental atopy and environmental exposure are recognized risk factors for atopic eczema (AE) in childhood. However, the relative contributions of specific risk factors and the overall contributions of hereditary and environmental exposure remain unexplored. Objectives To identify risk factors, estimate the population attributable risk (PAR) of environmental exposure, and compare the AE data for boys vs. girls in primary-school children. Methods During a February to June 2001 cross-sectional, Taiwan-based questionnaire survey, we investigated 23 980 children from 22 primary schools, all located within 1 km of an air-monitoring station. Results The 12-month prevalence of AE was reported as 6·1% in boys and 4·9% in girls. In both sexes, the risk of AE was strongly associated with parental atopy and perceived ambient air pollution. The presence of cockroaches [odds ratio (OR) 1·18, 95% confidence interval (CI) 1·00–1·40] and visible mould on walls at home (OR 1·46, 95% CI 1·22–1·70) were also significantly related to AE for girls; however, only visible mould on walls (and not the presence of cockroaches) at home was related to AE for boys (OR 1·40, 95% CI 1·18–1·66). While mutually adjusted models were applied, we found adjusted ORs and PARs were similar in boys and girls in hereditary and outdoor environmental factors. The PAR of indoor environmental factors was higher in girls (8·4%) than in boys (5·5%). There was no interaction between parental atopy and environmental factors. Conclusions Parental atopy contributed more to AE than indoor or outdoor environmental factors. Girls may be more susceptible to indoor environmental factors than boys.

Bacdground Atopy in maternal and family histories is known to be a risk factor for elevated umbilical cord immunoglobulin E (cIgE). However, the association between cIgE and psychosocial factors remains under investigation. Objective To explore whether psychosocial factors in addition to atopy contribute to elevated cIgE. Methods Four private maternity hospitals fitting the quantile levels of SO 2 in 2000 cooperated with us by recruiting participants for this study: pairs of mothers and neonates living within 3-km catchment areas of air-monitoring stations. We used a questionnaire to collect exposure data, and the Pharmacia UniCap IgE assay test system to determine the levels of IgE in gravidas and cord blood. Results Between July 2001 and March 2003, 334 mother and neonate pairs participated in this study. The frequencies of sensitization, serum IgE (sIgE)>100 IU/mL, or cIgE > 0.35 IU/mL were not different between the four different hospitals. By multi-variate logistic regression analysis adjusted for environmental factors, genetic factors, and psychosocial factors, the risk factors for elevated cIgE were being a male neonate (odds ratio (OR) = 3.5, 95% confidence interval (CI) = [1.5, 8.5]), carpets at home (OR = 3.0, 95% CI = [1.02, 8.4]), maternal allergy to dog dander (OR = 9.7, 95% CI = [1.2, 98.8], maternal total serum IgE>100 IU/mL (OR = 5.1, 95% CI = [2.2, 12.8]), maternal regularly/mostly/often self-reported nervousness (OR = 4.0, 95% CI = [1.3, 12.8]), family income $11574-17361/year (OR = 3.7, 95% CI = [1,3, 11.5]), incense burning (OR = 40, 95% CI = [1.4, 13.3]), and atopy in maternal grandparents (OR = 4.8, 95% CI = [1.7, 14.0]). By principle component analysis and logistic regression, psychosocial stress (β ± standard error = 0.26 ± 0.13, P = 0.04) was associated with increased cIgE. Conclusion Psychosocial factors are potentially important risk factors for elevated cIgE.

Multiple chemical sensitivity (MCS) is a syndrome in which multiple symptoms occur with low-level chemical exposure; whether it is an organic disease initiated by environmental exposure or a psychological disorder is still controversial. We report a 38-year-old male worker with chronic toluene exposure who developed symptoms such as palpitation, insomnia, dizziness with headache, memory impairment, euphoria while working, and depression during the weekend. Upon cessation of exposure, follow-up neurobehavioural tests, including the cognitive ability screening instrument and the mini-mental state examination, gradually improved and eventually became normal. Although no further toluene exposure was noted, non-specific symptoms reappeared whenever the subject smelled automotive exhaust fumes or paint, or visited a petrol station, followed by anxiety with sleep disturbance. During hospitalization for a toluene provocation test, there was no difference between pre-challenge and post-challenge PaCO(2), PaO(2), SaO(2) or pulmonary function tests, except some elevation of pulse rate. The clinical manifestations suggested that MCS was more relevant to psychophysiological than pathophysiological factors.

Interleukin (IL)-13 genetic polymorphisms have shown adverse effects on respiratory health. However, few studies have explored the interactive effects between IL-13 haplotypes and environmental exposures on childhood asthma. The aims of our study are to evaluate the effects of IL-13 genetic variants on asthma phenotypes, and explore the potential interaction between IL-13 and household environmental exposures among Taiwanese children. We investigated 3,577 children in the Taiwan Children Health Study from 14 Taiwanese communities. Data regarding children's exposure and disease status were obtained from parents using a structured questionnaire. Four SNPs were tagged accounting for 100% of the variations in IL-13. Multiple logistic regression models with false-discovery rate (FDR) adjustments were fitted to estimate the effects of IL-13 variants on asthma phenotypes. SNP rs1800925, SNP rs20541 and SNP rs848 were significantly associated with increased risks on childhood wheeze with FDR of 0.03, 0.04 and 0.04, respectively. Children carrying two copies of h1011 haplotype showed increased susceptibility to wheeze. Compared to those without carpet use and h1011 haplotype, children carrying h1011 haplotype and using carpet at home had significantly synergistic risks of wheeze (OR, 2.5; 95% CI, 1.4-4.4; p for interaction, 0.01) and late-onset asthma (OR, 4.7; 95% CI, 2.0-10.9; p for interaction, 0.02). In conclusions, IL-13 genetic variants showed significant adverse effects on asthma phenotypes among children. The results also suggested that asthma pathogenesis might be mediated by household carpet use.

BackgroundMales and females exhibit different health responses to air pollution, but little is known about how exposure to air pollution affects juvenile respiratory health after analysis stratified by allergic predisposition. The aim of the present study was to assess the relationship between air pollutants and asthmatic symptoms in Chinese children selected from multiple sites in a heavily industrialized province of China, and investigate whether allergic predisposition modifies this relationship.Methodology/principal findings30139 Chinese children aged 3-to-12 years were selected from 25 districts of seven cities in northeast China in 2009. Information on respiratory health was obtained using a standard questionnaire from the American Thoracic Society. Routine air-pollution monitoring data was used for particles with an aerodynamic diameter ≤10 µm (PM(10)), sulfur dioxide (SO(2)), nitrogen dioxides (NO(2)), ozone (O(3)) and carbon monoxide (CO). A two-stage regression approach was applied in data analyses. The effect estimates were presented as odds ratios (ORs) per interquartile changes for PM(10), SO(2), NO(2), O(3), and CO. The results showed that children with allergic predisposition were more susceptible to air pollutants than children without allergic predisposition. Amongst children without an allergic predisposition, air pollution effects on asthma were stronger in males compared to females; Current asthma prevalence was related to PM(10) (ORs = 1.36 per 31 µg/m(3); 95% CI, 1.08-1.72), SO(2) (ORs = 1.38 per 21 µg/m(3); 95%CI, 1.12-1.69) only among males. However, among children with allergic predisposition, more positively associations between air pollutants and respiratory symptoms and diseases were detected in females; An increased prevalence of doctor-diagnosed asthma was significantly associated with SO(2) (ORs = 1.48 per 21 µg/m(3); 95%CI, 1.21-1.80), NO(2) (ORs = 1.26 per 10 µg/m(3); 95%CI, 1.01-1.56), and current asthma with O(3) (ORs = 1.55 per 23 µg/m(3); 95%CI, 1.18-2.04) only among females.Conclusion/significanceAmbient air pollutions were more evident in males without an allergic predisposition and more associations were detected in females with allergic predisposition.

Background In western countries, late-onset asthmatics are more severe than early-onset asthmatics in clinic-based studies. However, whether asthma occurrence rates were higher in late ages than in younger ages was inconclusive. This information is essentially lacking in Asian population. Methods The participants were schoolchildren’s parents recruited from 94 elementary and middle schools in 2004. A cross-sectional self-administered questionnaire was sent through the children to their parents to survey their respiratory health. We investigated typical asthma symptoms occurring at different ages and subsequent remission or relapse after the first asthma event. Person-years of the participants from birth to the time of survey were used as the denominator. Results Among the 25,377 participants consisting of 949,807 total person-years, 860 reported ever having asthma. Highest incidences occurred at ages 0–12 and 36–40 years. The incidence of asthma was higher in males before puberty, and higher in females after puberty, with overall incidences 1.00 and 0.77 per 1000 person-years for females and males, respectively. Participants with late-onset asthma (onset age >12 years) comprised a large portion of adult current asthmatics. More than 52% of persistence or relapse was observed in early-onset asthma (onset age ≤12 years). The younger birth cohort had a more prominent later peak of asthma incidence than the older one. Conclusions In Asian population, asthma occurrence showed a U-shape age distribution with a prominent second peak in the thirties. A high proportion of early-onset asthma relapsed and most of late-onset asthma persisted or relapsed in adulthood.