Mingyu Xie

Impact of weather factors on hand, foot and mouth disease, and its role in short-term incidence trend forecast in Huainan City, Anhui Province.

Hand, foot, and mouth disease (HFMD) is one of the most common communicable diseases in China, and current climate change had been recognized as a significant contributor. Nevertheless, no reliable models have been put forward to predict the dynamics of HFMD cases based on short-term weather variations. The present study aimed to examine the association between weather factors and HFMD, and to explore the accuracy of seasonal auto-regressive integrated moving average (SARIMA) model with local weather conditions in forecasting HFMD. Weather and HFMD data from 2009 to 2014 in Huainan, China, were used. Poisson regression model combined with a distributed lag non-linear model (DLNM) was applied to examine the relationship between weather factors and HFMD. The forecasting model for HFMD was performed by using the SARIMA model. The results showed that temperature rise was significantly associated with an elevated risk of HFMD. Yet, no correlations between relative humidity, barometric pressure and rainfall, and HFMD were observed. SARIMA models with temperature variable fitted HFMD data better than the model without it (sR2 increased, while the BIC decreased), and the SARIMA (0, 1, 1)(0, 1, 0)52 offered the best fit for HFMD data. In addition, compared with females and nursery children, males and scattered children may be more suitable for using SARIMA model to predict the number of HFMD cases and it has high precision. In conclusion, high temperature could increase the risk of contracting HFMD. SARIMA model with temperature variable can effectively improve its forecast accuracy, which can provide valuable information for the policy makers and public health to construct a best-fitting model and optimize HFMD prevention.

Exposure to bisphenol A and the development of asthma: A systematic review of cohort studies

BACKGROUND There is conflicting evidence about the association between bisphenol A (BPA) exposure and childhood asthma risk. We aimed to review the epidemiological literature on the relationship between prenatal or postnatal exposure to BPA and the risk of childhood asthma/wheeze. METHODS The PubMed database was systematically searched, and additional studies were found by searching reference lists of relevant articles. RESULTS Six studies fulfilled the eligibility criteria. Three studies found that prenatal BPA exposure is associated with an increased risk of childhood wheeze, while another study reported a reduced risk of wheeze. Regarding the postnatal BPA exposure, three studies demonstrated an increased risk of childhood asthma/wheeze. CONCLUSIONS The mean prenatal BPA was associated with the risk of childhood wheeze/asthma. Besides, the influence of BPA exposure during the second trimester of pregnancy on the prevalence of childhood wheeze was marked. Further studies are urgently needed to explore the underlying mechanism about adverse effect of BPA exposure on childhood wheeze/asthma.

Prenatal antibiotic use and risk of childhood wheeze/asthma: A meta-analysis

Existing body of knowledge suggests that antibiotic use during pregnancy was inconsistently associated with childhood wheeze/asthma. The aim of this study was to determine whether exposure to antibiotic during pregnancy could increase the risk for childhood wheeze/asthma using a comprehensive meta‐analysis.

Is greater temperature change within a day associated with increased emergency admissions for schizophrenia

BACKGROUND Diurnal temperature range (DTR), as an important index of climate change, has been increasingly used to evaluate the impacts of temperature variability on human health. However, little is known about the effects of DTR on schizophrenia. OBJECTIVE The present study aims to examine the relationship between DTR and schizophrenia admissions, and further, to explore whether the association varied by individual characteristics and study periods. METHODS A Poisson generalized linear regression combined with distributed lag non-linear model (DLNM) was applied to analyze daily DTR and schizophrenia data from Hefei, China during 2005 to 2014, after adjusting for long-term and seasonal trends, mean temperature, relative humidity and other confounding factors. RESULTS An acute adverse effect of extremely high DTR on schizophrenia was observed, with a 2.7% (95% CI: 1.007-1.047) increase of daily schizophrenia admissions after exposure to extremely high DTR (95th percentile vs. 50th percentile). The risk for schizophrenia onset due to large DTR exposure increased from the first five years (2005-2009) to the second five years (2010-2014). Additionally, the patient aged 15-29 and 50-64years, male patients, patients born in spring/autumn, and married patients appeared to be more vulnerable to DTR effect. However, there was no significant association between moderately high DTR (75th percentile) and schizophrenia. CONCLUSIONS This study suggests that extremely high DTR is a potential trigger for schizophrenia admissions in Hefei, China. Our findings may provide valuable information to decisions-makers and guidance to health practitioners.

Ambient temperature, humidity and hand, foot, and mouth disease: A systematic review and meta-analysis

BACKGROUND The relationship between ambient temperature, humidity and hand, foot, and mouth disease (HFMD) has been highlighted in East and Southeast Asia, which showed multiple different results. Therefore, our goal is to conduct a meta-analysis to further clarify this relationship and to quantify the size of these effects as well as the susceptible populations. METHODS PubMed, Web of science, and Cochrane library were searched up to November 22, 2017 for articles analyzing the relationships between ambient temperature, humidity and incidence of HFMD. We assessed sources of heterogeneity by study design (temperature measure and exposed time resolution), population vulnerability (national income level and regional climate) and evaluated pooled effect estimates for the subgroups identified in the heterogeneity analysis. RESULTS We identified 11 studies with 19 estimates of the relationship between ambient temperature, humidity and incidence of HFMD. It was found that per 1°C increase in the temperature and per 1% increase in the relative humidity were both significantly associated with increased incidence of HFMD (temperature: IRR, 1.05; 95% CI, 1.02-1.08; relative humidity: IRR, 1.01; 95% CI, 1.00-1.02). Subgroup analysis showed that people living in subtropical and middle income areas had a higher risk of incidence of HFMD. CONCLUSIONS Ambient temperature and humidity may increase the incidence of HFMD in Asia-Pacific regions. Further studies are needed to clarify the relationship between ambient temperature, humidity and incidence of HFMD in various settings with distinct climate, socioeconomic, and demographic features.

The burden of extreme heat and heatwave on emergency ambulance dispatches: A time-series study in Huainan, China.

BACKGROUND Although studies have well documented increased mortality risk during extreme heat and heatwaves, few have examined their impacts on emergency ambulance dispatches under different temperature metrics. Additionally, evidence on the attributable risk of emergency ambulance dispatches due to extreme heat and heatwaves is scarce around the world. METHODS A distributed lag nonlinear model (DLNM) was applied to quantify the impact of extreme heat and heatwaves on emergency ambulance dispatches in Huainan, China, during 2011-2013. Several local extreme heat and heatwave definitions were tested by using percentile of daily mean temperature (i.e., 95th, 97.5th and 99th) and duration (i.e.,≥2 consecutive days and ≥3 consecutive days). The fraction of emergency ambulance dispatches attributable to extreme heat and heatwaves was also quantitatively estimated. RESULTS Both extreme heat and heatwaves were significantly associated with increases in emergency ambulance dispatches, and their effects appeared to be acute. For extreme heat effects, the relative risks (RRs) of emergency ambulance dispatches at lag0 steadily increased from 95th percentile of daily mean temperature (1.03, 95% confidence interval (CI): 1.01-1.05) to 99th percentile (1.07, 95% CI: 1.05-1.10). For heatwave effects, we observed that RRs of emergency ambulance dispatches at lag0 fluctuated between 1.03 and 1.05 across different heatwave definitions. Notably, the fraction of emergency ambulance dispatches attributable to extreme heat decreased with higher percentile of daily mean temperature, dropping from 2.24% (95% CI: 1.41%-2.99%) at 95th percentile to 0.69% (95% CI: 0.45%-0.92%) at 99th percentile. Likewise, we found that heatwaves with higher intensity and (or) longer duration accounted for lower fraction of emergency ambulance dispatches, varying between 0.51%-1.52%. CONCLUSIONS Our findings may have important implications for the development of local heat warming systems and public health interventions to lessen the impact of extreme heat events on population health.

Nonlinear and Interactive Effects of Temperature and Humidity on Childhood Hand, Foot and Mouth Disease in Hefei, China.

Background: Hand, foot and mouth disease (HFMD) is one of the major infectious diseases among children and remains a health threat, especially among Asian countries. Many epidemiologic studies suggested significant association of air temperature and humidity with childhood HFMD; however, evidence on the temperature effects on childhood HFMD in temperate cities is limited, and the interactive effects of temperature and humidity have not been studied yet. Methods: Daily counts of HFMD in children younger than 15 years of age and daily meteorologic variables during 2010 to 2012 were obtained in Hefei, China. A distributed lag nonlinear model was applied to estimate the potential nonlinear association between temperature and childhood HFMD. The interactive effects between temperature and humidity on childhood HFMD were also investigated. Results: Temperature rise was associated with higher risk of childhood HFMD. Within the incubation period of HFMD, temperature rise appeared to have the acute effects on childhood HFMD, and a 5°C increase of temperature at lag 0–6 days was associated with 24.8% (95% confidence interval: 11.94%–39.10%) increase of childhood HFMD. Females and children of 0–4 years of agewere more vulnerable to temperature rise. Notably, there were obvious combined effects between temperature and humidity on childhood HFMD—the risk of childhood HFMD elevated at higher temperature and humidity level. Conclusions: This study provides evidence that temperature and humidity may jointly affect childhood HFMD, and such interactive impact needs to be considered when evaluating the temperature–childhood HFMD relationship.

Asthma and Risk of Stroke: A Systematic Review and Meta-analysis

BACKGROUND Several studies have suggested that asthma is associated with an increased risk of stroke. However, the results are inconsistent. The aim of this study is to investigate the relation of asthma and the risk of stroke through a systematic review and meta-analysis of published research. METHODS Pertinent studies were identified by a search of the PubMed and the Web of Science databases to June 2015. Study-specific hazard ratios (HRs) with 95% confidence intervals (CIs) were pooled using fixed-effect or random-effect models when appropriate. Associations were tested in subgroups representing different participants and study characteristics. Publication bias was assessed with Eggers test. RESULTS Five articles comprising 524,637 participants and 6031 stroke cases were eligible for inclusion. Asthma was associated significantly with increased risk of stroke, and the pooled HR was 1.32 (95% CI: 1.13, 1.54, I(2)=80.4%). Subgroup analyses revealed that the association between asthma and stroke risk was stronger among female patients (HR = 1.42, 95% CI: 1.15-1.76) and prospective cohort study design (HR = 1.52, 95% CI: 1.21-1.91). CONCLUSION Asthma is associated with a significantly increased risk of stroke. This finding may have clinical and public health importance.

Effect of increasing temperature on daily hospital admissions for schizophrenia in Hefei, China: a time-series analysis

OBJECTIVE To investigate the relationship between ambient temperature and hospital admissions for schizophrenia in Hefei, China. STUDY DESIGN An ecological design was used to explore the effect of ambient temperature on hospital admissions for schizophrenia. METHODS Daily data on hospital admissions for schizophrenia and meteorological data for the warm season (May-October) in 2005-2014 were obtained from Anhui Mental Health Centre and Hefei Bureau of Meteorology, respectively. Poisson generalised linear regression model combined with a distributed lag non-linear model was used to analyse the effects of temperature on admissions for schizophrenia. Stratified analyses according to individual characteristics, such as age and sex, were also conducted. RESULTS A significant relationship was found between ambient temperature and admissions for schizophrenia. High temperature appeared to have a delayed effect on admissions for schizophrenia, and a temperature of 28°C (75th percentile) at lag 0-4 days was associated with a 7% (95% confidence interval: 4-11%) increase in admissions for schizophrenia. Stratified analyses showed that male patients, patients aged 21-60 years and married patients were more vulnerable to high temperature, and the temperature effects for those groups occurred at a lag of 1 day. CONCLUSION High temperature poses significant risks for schizophrenia in subtropical regions. Future preventive measures for reducing the occurrence of schizophrenia should be considered for susceptible populations.

Exposure to traffic-related air pollution and acute bronchitis in children: season and age as modifiers

Background Acute bronchitis (AB) is one of the principal causes of childhood morbidity. Increasing number of studies has shown that air pollution is an important environmental contributor of respiratory disease. However, evidence so far is scarce regarding the effects of air pollution on childhood AB, and it also remains unclear how the risk of AB will change by season and age. Methods Data on hospital visits for AB in children, air pollution and meteorological factors from 1 January 2015 to 31 December 2016 were collected in Hefei, China. Time-series analysis was applied to assess the short-term effects of traffic-related air pollution on childhood AB outpatient visits. A Poisson generalised linear regression model combined with a distributed lag non-linear model was used to estimate the relationships, controlling for long-term trends, seasonal patterns, meteorological factors and other possible confounders. Results We found that an IQR increase in concentrations of nitrogen dioxide, particulate matter <2.5 µm and carbon monoxide significantly increased the daily hospital visits for childhood AB with 4-day cumulative effect estimates (relative risks: 1.03, 95% CI 1.01 to 1.05; 1.09, 95% CI 1.07 to 1.11; 1.07, 95% CI 1.05 to 1.09). Notably, the risk estimates during the cold season are pronounced; however, no significant association was observed during the warm season. Interestingly, children aged 6–14 years were more vulnerable to air pollutants than children aged less than 1 year and within 1–5 years. However, no gender difference was observed. Conclusion A significant association of traffic-related air pollution and increased department visits for childhood AB was observed, notably in school-age children and during the cold season.