Limited studies have prospectively examined the role of body mass index (BMI) as a major risk factor for asthma during adolescence. This study investigates whether BMI is associated with increased risk of developing physician-diagnosed asthma during 12-month follow-up among adolescents with undiagnosed asthma-like symptoms at baseline.

Background: Previous studies have shown inconsistent results regarding the impact of traffic pollution on the prevalence of chronic obstructive pulmonary disease (COPD). Therefore, using frequency matching and propensity scores, we explored the association between traffic pollution and COPD in a cohort of 8284 residents in a major agricultural county in Taiwan. Methods: All subjects completed a structured questionnaire interview and health checkups. Subjects with COPD were identified using Taiwan National Health Insurance Research Databases. A hybrid kriging/LUR model was used to identify levels of traffic-related air pollutants (PM_2.5 and O₃). Multiple logistic regression models were used to calculate the prevalence ratios (PRs) of COPD and evaluate the role played by traffic-related indices between air pollutants and COPD. The distributed lag nonlinear model was applied in the analysis; we excluded current or ever smokers to perform the sensitivity analysis. Results: Increased PRs of COPD per SD increment of PM_2.5 were 1.10 (95% CI 1.05–1.15) and 1.25 (95% CI 1.13–1.40) in the population with age and sex matching as well as propensity-score matching, respectively. The results of the sensitivity analysis were similar between the single and two pollutant models. PM_2.5 concentrations were significantly associated with traffic flow including sedans, buses, and trucks (p < 0.01). The higher road area and the higher PM_2.5 concentrations near the subject’s residence correlated with a greater risk of developing COPD (p for interaction < 0.01). Conclusions: Our results suggest that long-term exposure to traffic-related air pollution may be positively associated with the prevalence of COPD. Graphical

Previous studies have indicated that women suffer from dry eye syndrome (DES) more significantly than men. Therefore, we specifically explore the associations between air pollutant levels and the risks of DES for women. The study obtained 27,605 participants from the 29 recruitment centers of the Taiwan Biobank, which was established in October 2012. A large scale cross-sectional study involving DES sufferers and age- and education-matched control groups without DES was designed. Based on the municipality of residence, the predicted concentration levels of various air pollutants, including PM_2.5, sulfur dioxide (SO₂), ozone (O₃), and nitrogen dioxide (NO₂) were estimated by using hybrid kriging/LUR model. Multiple logistic regressions were applied to estimate the prevalence ratios (PR) of DES and 95% confidence interval. Hormone supplementations, DBP, allergies, and arthritis were considered as important comorbidities for increased PR risk of DES. In addition, with each standard deviation (SD) increment of PM_2.5 and temperature, women had significant increases in PRs of DES of 1.09- and 1.07-fold, respectively; conversely, each SD increment of relative humidity (RH) had a protective effect against the risk of DES. After considering hormone supplementation, arthritis, and allergy, the SD increment of NO₂ and temperature were associated with the PRs of DES. In conclusion, significant associations of ambient NO₂ concentration, RH and temperature with DES indicated the importance of increased environmental protection in the female population. Female exposure to high levels of NO₂ when receiving hormone supplementation, or suffering with allergies or arthritis, had significantly increased risk of DES.

Chronic exposure to inorganic arsenic (iAs) is associated with chronic kidney disease (CKD) and urinary cancer, but the risks are poorly understood. Human biomonitoring can serve as a tool to better quantify human exposure and to conduct risk assessment. We aimed to assess the population risks of CKD and urinary cancer due to iAs intake based on the blood arsenic concentrations of 601 participants in Taiwan. A physiologically based pharmacokinetic modeling-based reverse dosimetry was conducted to estimate the daily intakes of iAs (DI_iAs). We performed the benchmark dose (BMD) modeling for CKD using participants' estimated glomerular filtration rate (eGFR) and the estimated DIiAs to derive a point of departure (POD). Margin of exposure (MOE) was used to characterize the risks. The population with eGFR values of <60 mL/min/1.73 m² had significantly higher DI_iAs (median: 3.20 μg/kg/day, 2.5th-97.5th percentiles: 2.35-4.67 μg/kg/day) than those with normal renal function (1.99, 1.22-3.42 μg/kg/day). The POD for CKD was 1.557 μg/kg/day, which could serve as a possible reference value for CKD risk assessment. The MOEs indicated that the CKD risk due to iAs intake may potentially be a cause for high concern for the population with reduced renal function. The iAs-induced urinary cancer risk may be a cause for moderate-to-high concern.