Few studies have used spatially resolved ambient particulate matter with an aerodynamic diameter of <10 μm (PM10) to examine the impact of PM10 on ischemic heart disease (IHD) mortality in China. The aim of our study is to evaluate the short-term effects of PM10 concentrations on IHD mortality by means of spatiotemporal analysis approach. We collected daily data on air pollution, weather conditions and IHD mortality in Beijing, China during 2008 and 2009. Ordinary kriging (OK) was used to interpolate daily PM10 concentrations at the centroid of 287 township-level areas based on 27 monitoring sites covering the whole city. A generalized additive mixed model was used to estimate quantitatively the impact of spatially resolved PM10 on the IHD mortality. The co-effects of the seasons, gender and age were studied in a stratified analysis. Generalized additive model was used to evaluate the effects of averaged PM10 concentration as well. The averaged spatially resolved PM10 concentration at 287 township-level areas was 120.3 ± 78.1 μg/m3. Ambient PM10 concentration was associated with IHD mortality in spatiotemporal analysis and the strongest effects were identified for the 2-day average. A 10 μg/m3 increase in PM10 was associated with an increase of 0.33% (95% confidence intervals: 0.13%, 0.52%) in daily IHD mortality. The effect estimates using spatially resolved PM10 were larger than that using averaged PM10. The seasonal stratification analysis showed that PM10 had the statistically stronger effects on IHD mortality in summer than that in the other seasons. Males and older people demonstrated the larger response to PM10 exposure. Our results suggest that short-term exposure to particulate air pollution is associated with increased IHD mortality. Spatial variation should be considered for assessing the impacts of particulate air pollution on mortality.
Hand-foot-mouth disease (HFMD) is a common infectious disease in China and occurs mostly in infants and children. Beijing is a densely populated megacity, in which HFMD has been increasing in the last decade. The aim of this study was to quantify spatio-temporal characteristics of HFMD and the relationship between meteorological factors and HFMD incidence in Beijing, China. Daily counts of HFMD cases from January 2010 to December 2012 were obtained from the Beijing Center for Disease Prevention and Control (CDC). Seasonal trend decomposition with Loess smoothing was used to explore seasonal patterns and temporal trends of HFMD. Bayesian spatiotemporal Poisson regression models were used to quantify spatiotemporal patterns of HFMD incidence and associations with meteorological factors. There were 114,777 HFMD cases reported to Beijing CDC from 1 January 2010 to 31 December 2012 and the raw incidence was 568.6 per 100,000 people. May to July was the peak period of HFMD incidence each year. Low-incidence townships were clustered in central, northeast and southwest regions of Beijing. Mean temperature, relative humidity, wind velocity and sunshine hours were all positively associated with HFMD. The effect of wind velocity was significant with a RR of 3.30 (95%CI: 2.37, 4.60) per meter per second increase, as was sunshine hours with a RR of 1.20 (95%CI: 1.02, 1.40) per 1 hour increase. The distribution of HFMD in Beijing was spatiotemporally heterogeneous, and was associated with meteorological factors. Meteorological monitoring could be incorporated into prediction and surveillance of HFMD in Beijing.
Background: Despite studies investigating the publication rates and factors influencing publication outcomes of clinical trials in some disease fields, there is a notable lack of research focusing on chronic obstructive pulmonary disease (COPD) clinical trials. This study aims to explore the characteristics of COPD-related clinical trials and identify factors associated with publication status and publication time. Methods: A systematic search was conducted on the World Health Organization International Clinical Trials Registry Platform on April 28, 2022, to identify completed interventional clinical trials related to COPD. Various trial features were analyzed, and factors influencing publication status and time were examined. Results: A total of 2577 completed interventional clinical trials focusing on COPD were identified. A total of 42.76% of trials enrolled <= 50 participants. The majority of trials were randomized (81.72%), blind (57.39%), parallel-assignment (59.14%), single-center (51.30%), multi-arm (83.86%), nonindustry funded (52.00%), and conducted for therapeutic purposes (73.11%). The 2-year cumulative publication rate was found to be 27.9%. The median time of study duration, dissemination lag, and publication lag were 17.27, 21.07, and 24.70 months, respectively. Multivariate analysis revealed that sample size, blind design, and study phase significantly influenced the likelihood of publication, while intervention model, primary purpose, study phase, funder, and study duration were significant factors affecting publication time. Conclusion: The findings highlight the inadequacy of large multi-center interventional clinical trials for COPD and indicate a low 2-year cumulative publication rate. Strengthening collaboration among investigators and adopting scientifically robust designs for larger phase 3 clinical trials are crucial to advancing COPD research and enhancing publication outcomes.