A statistical model for hospital admissions caused by seasonal diseases

We present a model based on two-order integer-valued autoregressive time series to analyze the number of hospital emergency service arrivals caused by diseases that present seasonal behavior. We also introduce a method to describe this seasonality, on the basis of Poisson innovations with monthly means. We show parameter estimation by maximum likelihood and model validation and show several methods for forecasting, on the basis of long-time means and short-time and long-time prediction regions. We analyze an application to model the number of hospital admissions per week caused by influenza.     

Hospital admissions for chronic obstructive pulmonary disease in the population aged 55 years or over in Finland during 1972–1992

Hospital admissions for patients with COPD (chronic obstructive pulmonary disease) as the primary diagnosis for the total Finnish population aged 55 years or over were collected from discharge register from 1972 to 1992. Numbers of admissions and days in hospital by sex and age in relation to total population and the duration of stay in hospital were analysed.A total of 188,570 admissions related to COPD were recorded. There was an average of 17.0 admissions per 1,000 persons per year for men and 2.1 for women. The annual increase in the number of such periods, relative to population, was +1.5% for men (95% confidence interval +0.8 to +2.1%) and +5.1% (+4.0 to +6.2%) for women. A steady upward trend was found in all age groups among women and in the age group 65 years or over among men. The mean number of hospitalisation days increased among women but tended to decrease from the late 1980's onwards among men. The average length of stay decreased from 16.4 days (median: 11 days) in 1972 to 9.6 days (median: 7 days) in 1992.An increase in the need of hospital services was consistent feature among women and older men. Preceding smoking prevalence in Finland, ageing of the population and some institutional factors are the probable aspects behind this trend.     

Air Pollution and Hospital Emergency Room Admissions for Chronic Obstructive Pulmonary Disease in Valencia,Spain

The short-term relationship between levels of air pollution and emergency room admissions for chronic obstructive pulmonary disease was assessed in Valencia, Spain. The design was an ecological time-series study in which daily variation in air pollution was related to emergency chronic obstructive pulmonary disease visits to one of the city's hospitals. The pollutants under investigation were Black Smoke, sulfur dioxide, nitrogen dioxide, carbon monoxide, and ozone. The degree of association was analyzed with Poisson autoregressive regression, for which trend, seasonal patterns, temperature, humidity, days of the week, and incidence of influenza were controlled. Increases of 10 μg/m³ in ozone levels (lag 5) and of 1 mg/m³ in carbon monoxide (lag 1) were associated with increases of 6.1 % (95% confidence interval [CI] = 2.2%, 10.1%) and of 3.9% (95% CI = 1.4%, 6.6%), respectively, in the expected chronic obstructive pulmonary disease cases. There was no significant association for the remainder of the pollutants. The described effects persisted even when the authors used models of differing specifications and when generalized additive models were used. The authors concluded that the results of this investigation, together with results of earlier research, demonstrate the significant effect of pollution on various health indicators within Valencia.     

Chemical properties of air pollutants and cause-specific hospital admissions among the elderly in Atlanta, Georgia

Background: Health risks differ by fine particle (aerodynamic diameter ≤ 2.5 μm) component, although with substantial variability. Traditional methods to assess component-specific risks are limited, suggesting the need for alternative methods.Objectives: We examined whether the odds of daily hospital admissions differ by pollutant chemical properties.Methods: We categorized pollutants by chemical properties and examined their impacts on the odds of daily hospital admissions among Medicare recipients > 64 years of age in counties in Atlanta, Georgia, for 1998–2006. We analyzed data in two stages. In the first stage we applied a case-crossover analysis to simultaneously estimate effects of 65 pollutants measured in the Aerosol Research and Inhalation Epidemiology Study on cause-specific hospital admissions, controlling for temperature and ozone. In the second stage, we regressed pollutant-specific slopes from the first stage on pollutant properties. We calculated uncertainty estimates using a bootstrap procedure. We repeated the two-stage analyses using coefficients from first-stage models that included single pollutants plus ozone and meteorological variables only. We based our primary analyses on exposures on day of admission.Results: We found that 24-hr transition metals and alkanes were associated with increased odds [0.26%; 95% confidence interval (CI), 0.02–0.48; and 0.37%; 95% CI, 0.04–0.72, respectively] of hospital admissions for cardiovascular disease (CVD). Transition metals were significantly associated with increased hospital admissions for ischemic heart disease, congestive heart failure, and atrial fibrillation. Increased respiratory-related hospital admissions were significantly associated with alkanes. Aromatics and microcrystalline oxides were significantly associated with decreased CVD- and respiratory-related hospital admissions.Conclusions: The two-stage approach showed transition metals to be consistently associated with increased odds of CVD-related hospital admissions.     

Chronic Exposure to Ambient Ozone and Asthma Hospital Admissions among Children

Background

The association between chronic exposure to air pollution and adverse health outcomes has not been well studied.

Objective

This project investigated the impact of chronic exposure to high ozone levels on childhood asthma admissions in New York State.

Methods

We followed a birth cohort born in New York State during 1995–1999 to first asthma admission or until 31 December 2000. We identified births and asthma admissions through the New York State Integrated Child Health Information System and linked these data with ambient ozone data (8-hr maximum) from the New York State Department of Environmental Conservation. We defined chronic ozone exposure using three indicators: mean concentration during the follow-up period, mean concentration during the ozone season, and proportion of follow-up days with ozone levels > 70 ppb. We performed logistic regression analysis to adjust for child’s age, sex, birth weight, and gestational age; maternal race/ethnicity, age, education, insurance status, smoking during pregnancy, and poverty level; and geographic region, temperature, and copollutants.

Results

Asthma admissions were significantly associated with increased ozone levels for all chronic exposure indicators (odds ratios, 1.16–1.68), with a positive dose–response relationship. We found stronger associations among younger children, low sociodemographic groups, and New York City residents as effect modifiers.

Conclusion

Chronic exposure to ambient ozone may increase the risk of asthma admissions among children. Younger children and those in low socioeconomic groups have a greater risk of asthma than do other children at the same ozone level.     

Associations between Outdoor Air Pollution and Hospital Admissions in Brisbane,Australia

The authors investigated the effects of ambient air pollution on hospital admissions in Brisbane, Australia. The authors used the Air Pollution on Health: European Approach protocol to examine the effects of particles, ozone, sulfur dioxide, and nitrogen dioxide on daily hospital admissions for asthma and respiratory, cardiovascular, and digestive disorders (control diagnosis) that occurred during the period 1987-1994. Ozone was consistently associated with admissions for asthma and respiratory disease—with little evidence of a threshold. In two-pollutant models, the ozone effect was relatively unaffected by the control for high levels of other pollutants. Particulate pollution (measured by nephelometry) was associated positively with admissions for respiratory disease and admissions for asthma in summer, whereas a negative association was observed for cardiovascular admissions. Although sulfur dioxide was associated significantly with admissions for respiratory and cardiovascular disease, a significant association was also found for the control diagnosis of digestive disorders. No significant associations were found for nitrogen dioxide over the study period, although significantly positive seasonal interactions were found for asthma and respiratory disease in autumn, winter, and spring. It was concluded that current levels of ambient air pollution in Brisbane make a significant contribution to the variation in daily hospital admissions for asthma and respiratory disease.     

Impact of urban air pollutants and noise levels over daily hospital admissions in children in Madrid: a time series analysis

Objective: The aim of this paper was to analyse the effects of the urban air pollutants and noise levels on daily emergency hospital admissions of children less than 10 years of age in Madrid. Material and methods: Poisson Regression Models were used to quantify the associations. Meteorological variables, influenza epidemics, pollen concentrations and trends and periodicities were used as controlling variables. Results: The main results obtained were the detected relationship (p<0.05) between emergency hospital admissions due to organic diseases and noise levels (AR=2.4%) and for PM₁₀ concentrations (AR=2.1%). For respiratory diseases statistically significant associations were detected for noise levels (AR=4.7%) and cold temperatures (AR=3.8%). The main association detected for causes of admissions due to bronchitis was for O₃ (AR=36.8%) and for pneumonia was for noise levels (AR=7.7%). Conclusion: The results obtained suggest that noise level particularly is a risk factor for daily emergency hospital admissions for organic and respiratory diseases in children less than 10 years old in Madrid.     

融合空气数据的深度网络慢阻肺评估测试评分预测模型的构建及意义CSCD

Objective To construct a chronic obstructive pulmonary disease (COPD) assessment test (CAT) score prediction model based on a deep network fused with air data, and to explore its significance. Methods From February 2015 to December 2017, the outdoor environmental monitoring air data near the residential area of the patients with COPD from the Respiratory Outpatient Clinics of Peking University Third Hospital, Peking University People′s Hospital and Beijing Jishuitan Hospital were collected and the daily air pollution exposure of patients was calculated. The daily CAT scores were recorded continuously. The CAT score of the patients in the next week was predicted by fusing the time series algorithm and neural network to establish a model, and the prediction accuracy of the model was compared with that of the long short‑term memory model (LSTM), the LSTM‑attention model and the autoregressive integrated moving average model (ARIMA). Results A total of 47 patients with COPD were enrolled and followed up for an average of 381.60 days. The LSTM‑convolutional neural networks (CNN)‑autoregression (AR) model was constructed by using the collected air data and CAT score, and the root mean square error of the model was 0.85, and the mean absolute error was 0.71. Compared with LSTM, LSTM‑attention and ARIMA, the average prediction accuracy was improved by 21.69%. Conclusion Based on the air data in the environment of COPD patients, the fusion deep network model can predict the CAT score of COPD patients more accurately. © 2021 Journal of Clinical Otorhinolaryngology Head and Neck Surgery. All rights reserved.     

Air pollution and cardiovascular admissions association in Spain: results within the EMECAS project

OBJECTIVE: To evaluate the short term effect of air pollution on cardiovascular admissions in 14 Spanish cities METHODS: The period under study was from 1995 to 1999. Daily emergency admissions for all cardiovascular diseases (CVD) and heart diseases (HD) were obtained from hospital records, and the corresponding daily levels of particulates, SO2, NO2, CO, and ozone were recorded. The magnitude of association was estimated using Poisson generalised additive models controlling for confounding and overdispersion. For each cause, lagged effects, up to three days, of each pollutant were examined and combined estimates were obtained. For ozone the analyses were restricted to the warm period. One and two pollutant models were performed. RESULTS: Associations were more consistent in lag 0 (concurrent day) and 1 (lag 0-1), except in the case of ozone where there was a more delayed relation (lag 2-3). For combined estimates an increase of 10 microg/m3 in the PM10 levels in lag 0-1 was associated with an increase of 0.9% (95% CI: 0.4 to 1.5%) in the number of hospital admissions for CVD, and 1.6% (0.8 to 2.3%) for HD. For ozone the corresponding estimates for lag 2-3 were 0.7% (0.3 to 1.0) for CVD, and 0.7% (0.1 to 1.2) for HD. An increase of 1 mg/m3 in CO levels was associated with an increase of 2.1% (0.7 to 3.5%) in CVD admissions, and 4.2% (1.3 to 7.1%) in HD admissions. SO2 and NO2 estimates were more sensitive in two pollutant models CONCLUSIONS: A short term association between increases in daily levels of air pollutants and the number of daily admissions for cardiovascular diseases, with specificity for heart diseases, has been described in Spanish cities.     

Particulate matter and daily mortality and hospital admissions in the west midlands conurbation of the United Kingdom: associations with fine and coarse particles, black smoke and sulphate

OBJECTIVES—There is considerable evidence linking ambient particles measured as particulate matter with aerodynamic diameter <10 µm (PM₁₀) to daily mortality and hospital admissions but it is not clear which physical or chemical components of the particle mixture are responsible. The relative effects of fine particles (PM_2.5), coarse particles (PM_2.5-10), black smoke (mainly fine particles of primary origin) and sulphate (mainly fine particles of secondary origin) were investigated, together with ozone, SO₂, NO₂, and CO, on daily mortality and hospital admissions in the west Midlands conurbation of the United Kingdom.
METHODS—Time series of health outcome and environmental data were obtained for the period 1994-6. The relative risk of death or hospital admission was estimated with regression techniques, controlling for long term time trends, seasonal patterns, influenza epidemics, effects of day of the week, and temperature and humidity. Models were adjusted for any remaining residual serial correlation and overdispersion. The sensitivities of the estimates for the effects of pollution to the inclusion of a second pollutant and seasonal interactions (warm or cool) were also examined.
RESULTS—Daily all cause mortality was not associated with any gaseous or particulate air pollutant in the all year analysis, although all measures of particles apart from PM_2.5-10 showed significant positive effects of the warm season. Neither respiratory nor cardiovascular admissions (all ages) were associated with any air pollutant, and there were no important seasonal interactions. However, analysis of admissions by age found evidence for various associations—notably between PM₁₀, PM_2.5, black smoke, SO_2, and ozone (negative) and respiratory admissions in the 0-14 age group. The coarse fraction, PM_2.5-10 differed from PM_2.5 in having smaller and less consistent associations (including several large significant negative associations) and a different lag distribution. The results for black smoke, an indicator of fine primary carbonaceous particles, were very similar to those for PM_2.5, and tended to be more robust in two pollutant models. The effects of sulphate, an indicator of secondary particles, also showed some similarities to those of PM_2.5.
CONCLUSIONS—Clear effects of air pollution on mortality and hospital admissions were difficult to discern except in certain age or diagnostic subgroups and seasonal analyses. It was also difficult to distinguish between different measures of particles. Within these limitations the results suggest that the active component of PM₁₀ resides mostly in the fine fraction and that this is due mainly to primary particles from combustion (mainly vehicle) sources with a contribution from secondary particles. Effects of the coarse fraction cannot be excluded.


Keywords: air pollution particulates; mortality; hospital admissions     

慢性气道炎症性疾病中细胞因子作用研究进展

慢性气道炎症性疾病是由炎症细胞、结构细胞及多种细胞因子参与的感染、变态反应等引起的呼吸系统疾病,其病因、发病机制较为复杂,迄今尚未完全清楚。细胞因子在慢性气道炎症性疾病的发生发展中发挥着重要作用。本文以慢性阻塞性肺疾病(COPD)和哮喘为例对细胞因子在慢性气道炎症性疾病中的作用进行综述。     

Fine particulate matter on hospital admissions for acute exacerbation of chronic obstructive pulmonary disease in southwestern Taiwan during 2006–2012

This study explored the effects of PM_2.5 on hospital admissions (HAs) for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) in southwestern Taiwan. Data on HAs for AECOPD, pollutants, and meteorological variables were obtained from the National Health Insurance Research Database and Environmental Protection Administration. The relative risks (RRs) of HAs for AECOPD was estimated using the Quasi-Poisson generalized additive model. A total of 38,715 HAs for AECOPD were recorded. The average daily HAs for AECOPD and mean 24-h average level of PM_2.5 were 15.2 and 38.8 µg/m³, respectively. For both single and multiple pollutant (adjusted for O₃ and NO₂) models, increased AECOPD admissions were significantly associated with PM_2.5 during cold season, with the RRs for every 10 µg/m³ increase in PM_2.5 being 1.02 (95% CI = 1.007–1.040) at lag 0–1 in single-pollutant, and 1.02 (95 % CI = 1.001–1.042) at lag 0 day in multiple pollutant model. People 65 years of age and older had higher risk of HAs for AECOPD after PM_2.5 exposure. The RRs of PM_2.5 on HAs for AECOPD were robust after adjusting for O₃ and NO₂. Findings reveal an association between PM_2.5 and HAs for AECOPD in southwestern Taiwan, particularly during cold season.     

Cardiorespiratory health effects associated with sulphurous volcanic air pollution

OBJECTIVE: To investigate cardiorespiratory health effects associated with chronic exposure to volcanogenic sulphur dioxide (SO2) and fine sulphate particle (< or = 0.3 microm) air pollution emitted from Kilauea Volcano, Hawaii. STUDY DESIGN: Environmental-epidemiological cross-sectional study. METHODS: An air study was conducted to measure exposure levels in the downwind area, and to confirm non-exposure in a reference area. Cross-sectional health data were collected from 335 adults, > or = 20 years of age, who had resided for > or = 7 years in the study areas. Prevalence was estimated for cardiorespiratory signs, and self-reported symptoms and diseases. Logistic regression analysis estimated effect measures between exposed and unexposed groups considering potential confounding including age, gender, race, smoking, dust and body mass index (BMI). Student's t-tests compared mean differences in blood pressure (BP), pulse and respiratory rates. RESULTS: There were statistically significant positive associations between chronic exposure and increased prevalence of cough, phlegm, rhinorrhoea, sore/dry throat, sinus congestion, wheezing, eye irritation and bronchitis. The magnitude of the associations differed according to SO2 and fine sulphate particulate exposure. Group analyses found no differences in pulse rate or BP; however, significantly faster mean pulse rates were detected in exposed non-medicated, non-smoking participants with BMI <25, and in participants aged > or = 65 years. Higher mean systolic BP was found in exposed participants with BMI <25. CONCLUSIONS: Long-term residency in active degassing volcanic areas may have an adverse effect on cardiorespiratory health in adults. Further study at Kilauea is recommended, and the authors encourage investigations in communities near active volcanoes worldwide. Public health interventions of community education, and smoking prevention and cessation are suggested.     

慢性阻塞性肺疾病痰培养和药敏结果分析

目的通过对慢性阻塞性肺疾病(COPD)痰培养及药敏结果进行分析,为治疗COPD合理应用抗生素提供依据。方法对我院近期具有完整细菌学资料的COPD患者痰培养及药敏试验结果进行分析。结果122例患者痰样本中分离出病原菌198株,革兰阴性杆菌155株,占78.3%,主要为铜绿假单孢菌、大肠埃氏菌、克雷伯杆菌、阴沟杆菌等,而革兰阳性菌以金黄色葡萄球菌和表皮葡萄球菌为多。细菌药敏试验发现,假单胞菌属耐药率高,以铜绿假单胞菌明显,肠杆菌科次之,革兰氏阳性球菌耐药性相对较低。结论COPD病原菌对多种抗菌药物的耐药率有上升趋势,应加强药敏测定,合理应用抗生素,联合用药,减少细菌耐药菌株的产生。     

颅脑损伤合并医院内肺部感染的病原体分析

目的了解颅脑损伤病人发生医院肺部感染的病原茵情况,探讨其防治策略及细菌耐药性。方法回顾126例颅脑损伤病人医院内肺部感染痰培养的病原菌及药敏实验结果。结果引起医院内肺部感染的细菌特别是气管切开后病人肺部感染细菌培养阳性,占22,22％,培养出致病菌10种共52株,以革兰染色阴性（G）杆菌为主,共35株,占67．31％,革兰染色阳性（G^＋）球菌为,共11株,占21．15％,另6株为真菌,占11．54％。经抗感染治疗肺部感染痊愈12例,控制3例．死亡13例．死亡的13例中肺部感染均未能得到有效控制,其耐药普遍。结论颅脑损伤患者气管切开后肺部感染发生率高,病原体主要以G^-杆菌为主．肺部感染可使病情加重,是导致病人死亡的一个重要原因。     

Air particulate pollution due to bushfires and respiratory hospital admissions in Brisbane, Australia

To examine the impact of bushfire smoke on hospital admission rates for respiratory disease, a time series study was conducted in Brisbane, Australia. Data on particles of 10 microns or less in aerodynamic diameter (PM10) per cubic metre, bushfire events, meteorological conditions, and daily respiratory hospital admissions were obtained for the period of 1 July 1997 to 31 December 2000. A generalized linear model with the negative binomial distribution was used to estimate the effects of bushfire smoke on respiratory hospital admissions. The results of this study show that daily respiratory hospital admission rates consistently increased with increasing levels of PM10 for both bushfire and non-bushfire periods. This relationship appeared stronger during bushfire periods than non-bushfire periods, especially for the current day. The findings suggest that bushfire smoke was statistically significantly associated with an increased risk of respiratory hospital admissions in Brisbane (p < 0.05). The health impact assessment needs to be considered in the control and management of bushfires.     

Air pollution from bushfires and their association with hospital admissions in Sydney,Newcastle and Wollongong,Australia 1994–2007

Objective : We examined the association between validated bushfire smoke pollution events and hospital admissions in three eastern Australian cities from 1994 to 2007. Methods : Smoke events were defined as days on which bushfire smoke caused the 24‐hour citywide average concentration of airborne particles to exceed the 99^th percentile of the daily distribution for the study period. We used a time‐stratified case‐crossover design to assess the association between smoke events and hospital admissions. Odds ratios (OR) and 95% confidence intervals (CI) were estimated for cardiovascular and respiratory conditions on event days compared with non‐event days. Models were adjusted for daily meteorology, influenza epidemics and holidays. Results : Smoke events occurred on 58 days in Sydney (population: 3,862,000), 33 days in Wollongong (population: 406,000) and 50 days in Newcastle (population: 278,000). In Sydney, events were associated with a 6% (ORequals;1.06, 95%CI=1.02–1.09) same day increase in respiratory hospital admissions. Same day chronic obstructive pulmonary disease admissions increased 13% (ORequals;1.13, 95%CI=1.05–1.22) and asthma admissions by 12% (ORequals;1.12, 95%CI=1.05–1.19). Events were also associated with increased admissions for respiratory conditions in Newcastle and Wollongong. Conclusions : Smoke events were associated with increased hospital admissions for respiratory but not cardiovascular conditions. Large populations are needed to assess the impacts of brief exposures. Implications : Public health impacts from bushfire pollution events are likely to increase in association with a warming climate and more frequent severe fire weather.     

Fungal and other spore counts as predictors of admissions for asthma in the Trent region

OBJECTIVES—The importance of airborne fungal and other spores in provoking asthma attacks is uncertain. Panel studies have generated evidence that suggests a link between outdoor spore counts and severity of asthma. There have been no population based time series studies relating outdoor exposure to spores with incidence of attacks of asthma.
METHODS—Outcomes were hospital admissions for asthma on 2002 days during 1987-94, for children and adults in the Trent region of England. Predictors were daily counts of 25 spore taxa from volumetric traps in Derby on the same and previous day. Admissions for asthma were adjusted for weekly, seasonal, and longer term trends by log linear autoregressive models. Spore counts on 6 days of asthma epidemics were also examined.
RESULTS—When spore counts for individual taxa were analysed as quantitative variables, two positive and two negative correlations (out of a possible 100) were significant at the 5% level. When spore counts were dichotomised at the 90th percentile, one negative and eight positive correlations (out of 100) were significant at the 5% level. All significantly positive associations related to admissions among children, but none involved the total spore count. However, total spores were above the 90th percentile on four of the six epidemic days (odds ratio (OR) 9.92, 95% confidence interval (95% CI) 1.41 to 109.84), but epidemics occurred on only four of 343 days with high total moulds.
CONCLUSIONS—There was some evidence that exceptional rates of admission for asthma tend to occur on days with high total mould spore counts, but no specific taxon was consistently implicated. The predictive power was insufficient to support a public warning system.


Keywords: asthma; hospital admissions; moulds; fungi; spore counts; aeroallergens; log linear autoregression     

2005-2012年武汉市大气污染对呼吸系统疾病日住院人数的影响

目的 探讨武汉市大气污染对居民呼吸系统疾病日住院人数的影响.方法 收集2005年1月1日-2012年12月31日武汉市每日空气污染指数(API)、气象(平均气压、气温、气湿)资料,以及武汉市某三甲医院呼吸系统疾病住院数据,选用广义相加模型(GAM)的Poisson回归,研究大气污染对居民呼吸系统疾病日住院人数的影响.结果 API每上升一个四分位间距(37个单位),在累积滞后01天(lag01)总呼吸系统疾病住院人数增加最大,为6%(RR=1.06,95%CI:1.015~1.107).男性比女性对空气污染更敏感,男性在API上升累积滞后01天(lag01)RR值最大,为1.069(1.016~1.125),女性则在当天RR值最大,为1.048(0.975~1.127).≥65岁人群较0~64岁人群更为易感.≥65岁和0~64岁人群在API上升累积滞后01天(lag01)RR值最大,分别为1.075(1.012~1.141)和1.046(0.982~1.115).慢性阻塞性肺疾病(COPD)患者日住院人数在API上升累积滞后01天(lag01)RR值最大,为1.095(1.004~1.194),肺炎患者日住院人数增幅在滞后1天(lag1)最大,RR为1.019(0.951~1.092).API对呼吸系统疾病住院人数的影响冷季节>暖季节.结论 大气污染可增加居民呼吸系统疾病日住院人数,并对不同性别、年龄、呼吸系统疾病类型和季节的影响存在差异.