大气污染物与呼吸系统疾病急诊就诊关系的病例交叉研究

目的 分析大气污染急性暴露对呼吸系统疾病急诊人次的影响.方法 收集2004年1月1日至2005年12月31日北京大学第三医院急诊科呼吸系统疾病急诊资料和北京市环境监测中心大气污染物数据,应用时间分层的病例交叉设计研究方法进行数据分析,同时比较单向回顾性对照设计和双向对照设计研究结果的差异.结果 在调整气象因素并采用单向回顾性(多污染物)模型中,无滞后大气可吸入颗粒物(PM10)、二氧化硫(SO2)、滞后2 d二氧化氮(NO2)日平均浓度每增加10 μg/m3,呼吸系统疾病总急诊的OR值(95%CI)分别为1.010(1.005～1.014)、1.010(1.001～1.018)、0.996(0.983～1.009);双向对称性(多污染物)模型中,其相应OR值(95%CI)分别为1.002(0.998～1.005)、1.011(1.003～1.018)、1.012(1.001～1.022).采用不同对照选择方案,病例交叉设计的研究结果有变化.结论 区域内大气污染物暴露对居民呼吸系统疾病急诊人次有急性效应.     

The effect of particulate air pollution on emergency admissions for myocardial infarction: a multicity case-crossover analysis

Recently, attention has focused on whether particulate air pollution is a specific trigger of myocardial infarction (MI). The results of several studies of single locations assessing the effects of ambient particular matter on the risk of MI have been disparate. We used a multicity case-crossover study to examine risk of emergency hospitalization associated with fine particulate matter (PM) with aerodynamic diameter < 10 microm (PM10) for > 300,000 MIs during 1985-1999 among elderly residents of 21 U.S. cities. We used time-stratified controls matched on day of the week or on temperature to detect possible residual confounding by weather. Overall, we found a 0.65% [95% confidence interval (CI), 0.3-1.0%] increased risk of hospitalization for MI per 10 microg/m3 increase in ambient PM10 concentration. Matching on apparent temperature yielded a 0.64% increase in risk (95% CI, 0.1-1.2%). We found that the effect size for PM10 doubled for subjects with a previous admission for chronic obstructive pulmonary disease or a secondary diagnosis of pneumonia, although these differences did not achieve statistical significance. There was a weaker indication of a larger effect on males but no evidence of effect modification by age or the other diagnoses. We also found that the shape of the exposure-response relationship between MI hospitalizations and PM10 is almost linear, but with a steeper slope at levels of PM10 < 50 microg/m3. We conclude that increased concentrations of ambient PM10 are associated with increased risk of MI among the elderly.     

Gaseous air pollution and emergency hospital visits for hypertension in Beijing,China: a time-stratified case-crossover study

Background  

A number of epidemiological studies have been conducted to research the adverse effects of air pollution on mortality and morbidity. Hypertension is the most important risk factor for cardiovascular mortality. However, few previous studies have examined the relationship between gaseous air pollution and morbidity for hypertension.     

青岛市市南区1959～2000年病毒性肝炎流行特征分析

为全面了解病毒性肝炎的发病情况及其流行规律 ,为制订防制措施提供依据 ,现将青岛市市南区 4 2年来的病毒性肝炎疫情资料分析如下。1.流行概况 :本区自 195 9年有疫情记载以来至 2 0 0 0年病毒性肝炎累计发病 2 170 2例 ,死亡 11例 ,病死率为 0 .0 5 %。4 2年平均发病率为 196 .86 / 10万 ,发病率波动在 2 7.0 2 /10万～ 6 5 2 .94 / 10万 ,其中 196 0年发病率最高 ,为 6 5 2 .94 /10万 ;2 0 0 0年最低 ,为 2 7.0 2 / 10万 ,进入 1989年以来未发生死亡病例。肝炎发病位次由 2 0世纪 70年代至 90年代初的第 2位 ,逐步下降至 1999～ 2 0 0 0…     

Effects of urban air pollution on emergency room admissions for chronic obstructive pulmonary disease

The authors assessed the relation between sulfur dioxide and other air pollutants (black smoke, carbon monoxide, nitrogen dioxide, and ozone) and daily emergency room admissions for chronic obstructive pulmonary disease in Barcelona, Spain, during 1985-1986. Barcelona is a Mediterranean city of 1.7 million inhabitants that has air pollution levels lower than standard values. A weak but statistically significant association between emergency room admissions and levels of sulfur dioxide, black smoke, and carbon monoxide was observed. Daily emergency room admissions for chronic obstructive pulmonary disease increased by 0.02 and 0.01 for each microgram of sulfur dioxide and black smoke per cubic meter, respectively, and 0.11 for each milligram of carbon monoxide per cubic meter, after adjusting for meteorologic and temporal variables. Similar estimations were obtained after controlling for the autocorrelation effect by means of time series analysis. In addition, when the data were stratified by season, the effects remained in summer. This strengthened the conclusion that the relation observed in winter, spring, and throughout the study period was indeed real. After truncating the data according to sulfur dioxide or black smoke levels, the authors still found effects for these pollutants at levels below the air quality guideline of 100 micrograms/m3 established by the World Health Organization. The consistency of these results with other recent toxicologic and epidemiologic observations suggest that current air pollution standards do not totally protect public health with a margin of safety in specific places.     

Fine particulate air pollution and hospitalization for pneumonia: a case-crossover study in Shijiazhuang,China

Many epidemiological studies have shown that airborne particulate matter (PM) is a risk factor for multiple respiratory diseases and increased hospitalization rates. Fine PM (PM_2.5, diameter <2.5 μm) is considered to be a greater health hazard than coarse PM (PM₁₀, 2.5–10 μm) because it adsorbs more harmful substances and can enter deeper parts of the lungs. We investigated the correlation between hospitalization for pneumonia and PM_2.5 levels in Shijiazhuang, a city in northern China. Daily data on hospitalizations for community-acquired pneumonia and ambient air pollution levels in Shijiazhuang were obtained for 2013. A bidirectional case-crossover design was used to investigate the association between hospitalization for pneumonia and atmospheric PM_2.5, PM₁₀, SO₂, NO₂, CO, and O₃ levels. The effects of pollutant levels from lag0 (day of hospitalization) to lag5 (five days before lag0) were investigated in both single and multi-pollutant models, adjusted for daily weather variables. For the single-pollutant model, hospitalization for pneumonia correlated positively with higher PM_2.5 levels, with an increase of 1.1 % in daily admissions per 10-μg/m³ increase in the PM_2.5 level at lag0. In the multi-pollutant model, the observed effects of PM_2.5 remained significant. Stratified analysis of exposure based on sex, age, season, and comorbidities showed that the effect of PM_2.5 on hospitalization for pneumonia was stronger in males, people younger than 60 years, people without comorbidities, and on warm days. These results indicate that higher levels of PM_2.5 increase the risk of hospitalization for pneumonia in Shijiazhuang, China.     

Short-term associations between emergency hospital admissions for respiratory and cardiovascular disease and outdoor air pollution in London

There are concerns about the possible short-term effects of outdoor air pollution on health in the United Kingdom. In a study conducted during the time period between 1987 and 1992, investigators determined that ozone had small, but significant effects on emergency respiratory admissions. In the current study, the authors investigated associations between emergency admissions and outdoor air pollution for the time period from 1992 to 1994, inclusive, and compared the results with those obtained in the earlier study. The authors also examined particulate matter less than 10 microm in diameter (PM10) and carbon monoxide in the current study. Appropriate confounding factors, such as seasonal patterns, temperature, and humidity, were controlled for, and the authors used Poisson regression to estimate the association between daily emergency admissions for respiratory and cardiovascular diseases and ozone, nitrogen dioxide, sulfur dioxide, carbon monoxide, particles measured as Black Smoke, and PM10. Significant positive associations were found between emergency hospital admissions for respiratory disease and PM10 and sulfur dioxide, but such an association did not exist for ozone. The results were not significantly different from earlier results from London and were comparable with those determined in North America and Europe. Cardiovascular disease was associated with carbon monoxide and Black Smoke, but weaker associations existed with the other pollutants studied.     

Outdoor air pollution and emergency department visits for asthma among children and adults: A case-crossover study in northern Alberta,Canada

Background  

Recent studies have observed positive associations between outdoor air pollution and emergency department (ED) visits for asthma. However, few have examined the possible confounding influence of aeroallergens, or reported findings among very young children.     

Acute effects of urban air pollution on respiratory emergency hospital admissions in the Canary Islands

In the cities of Las Palmas (L/P) de Gran Canaria and Santa Cruz (S/C) de Tenerife, Canary Islands, particulate matter is highly influenced by mineral dust because their proximity to the Sahara desert (PM_10–2.5 levels are higher than PM_2.5). In this context, the short-term association between different PM fractions and gaseous pollutants with emergency hospital admissions for all respiratory, chronic obstructive pulmonary disease (COPD) and asthma was analyzed, evaluating the potential independent effect of PM_10–2.5. A generalized additive model was fitted controlling for seasonal patterns and time varying confounders. Different lag structures, polynomial distributed lag models, and two-pollutant models were examined. Under Lag01, in S/C de Tenerife, a 10 μg/m³ increase in PM_2.5 and PM_10–2.5 was associated with a 5.1 % risk increase (95 % confidence interval [CI] 1.0 to 9.2) in all respiratory and with a 7.7 % increase (95 % CI 0.9 to 14.9) in COPD emergency admissions, respectively. In L/P de Gran Canaria, a positive association between PM_10–2.5, PM_2.5, and NO₂ with the increased risk of asthma hospitalization was found: 11.2 % (95 % CI 0.5 to 22.9), 21.9 % (95 % CI 6.9 to 39.0), and a 17.4 % (95 % CI 6.6 to 29.4), respectively. The overall findings suggest that in these cities, (1) PM_2.5, PM_10–2.5, and NO₂ are associated with the risk of emergency hospital admission for respiratory diseases; (2) there is no evidence of confounding for the associations observed; and (3) PM_10–2.5 may have an impact on public health.     

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 microg/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 indicaors within Valencia.     

气温变化与心脑血管疾病急诊关系的病例交叉研究

目的 探讨北京市日平均气温与心脑血管疾病急诊(ICD-10:I00～I99)的关系,研究气温变化对心脑血管疾病的影响.方法 收集北京大学第三医院急诊科心脑血管疾病急诊资料、北京市气象资料和北京市大气污染物数据,应用时间分层的病例交叉设计研究方法分析春季(3-5月)、夏季(6-8月)、秋季(9-11月)、冬季(12-2月)日平均气温与心脑血管疾病急诊的关系.结果 在控制二氧化硫(SO2)、二氧化氮(NO2)及大气可吸入颗粒物(PM10)影响的情况下,春季、夏季、秋季、冬季当日平均气温对心脑血管疾病急诊的影响最大,平均气温每升高1℃与心脑血管疾病急诊的OR值分别为1.282(95%CI:1.250 ～1.315)、1.027(95% CI:1.001～1.055)、0.661(95% CI:0.637～0.687)、0.960(95%CI:0.937～0.984),关联有统计学意义(P<0.05).当同时调整相对湿度、风速、大气压强的影响时,春季、夏季、秋季、冬季平均气温与心脑血管疾病急诊的OR值分别为1.423(95%CI:1.377～1.471)、1.082(95%CI:1.041～1.124)、0.633(95%CI:0.607～0.660)、0.971(95%CI:0.944～1.000).关联有统计学意义(P<0.05).结论 春季、夏季日平均气温升高可以导致心脑血管疾病急诊人次增加,说明春夏季气温升高对心脑血管疾病患者是危险因素,应注意防暑;秋季、冬季气温升高可以导致心脑血管疾病急诊减少,说明秋冬季气温升高对心脑血管疾病患者是保护性因素,应注意保暖.     

Extreme precipitation and emergency room visits for influenza in Massachusetts: a case-crossover analysis

Background

Influenza peaks during the wintertime in temperate regions and during the annual rainy season in tropical regions – however reasons for the observed differences in disease ecology are poorly understood. We hypothesize that episodes of extreme precipitation also result in increased influenza in the Northeastern United States, but this association is not readily apparent, as no defined ‘rainy season’ occurs. Our objective was to evaluate the association between extreme precipitation (≥ 99th percentile) events and risk of emergency room (ER) visit for influenza in Massachusetts during 2002–2008.

Methods

A case-crossover analysis of extreme precipitation events and influenza ER visits was conducted using hospital administrative data including patient town of residence, date of visit, age, sex, and associated diagnostic codes. Daily precipitation estimates were generated for each town based upon data from the National Oceanic and Atmospheric Administration. Odds ratio (OR) and 95% confidence intervals (CI) for associations between extreme precipitation and ER visits for influenza were estimated using conditional logistic regression.

Results

Extreme precipitation events were associated with an OR = 1.23 (95%CI: 1.16, 1.30) for ER visits for influenza at lag days 0–6. There was significant effect modification by race, with the strongest association observed among Blacks (OR = 1.48 (1.30, 1.68)).

Conclusions

We observed a positive association between extreme precipitation events and ER visits for influenza, particularly among Blacks. Our results suggest that influenza is associated with extreme precipitation in a temperate area; this association could be a result of disease ecology, behavioral changes such as indoor crowding, or both. Extreme precipitation events are expected to increase in the Northeastern United States as climate change progresses. Additional research exploring the basis of this association can inform potential interventions for extreme weather events and influenza transmission.

     

Ambient air pollution and respiratory emergency department visits

BACKGROUND: A number of emergency department studies have corroborated findings from mortality and hospital admission studies regarding an association of ambient air pollution and respiratory outcomes. More refined assessment has been limited by study size and available air quality data. METHODS: Measurements of 5 pollutants (particulate matter [PM10], ozone, nitrogen dioxide [NO2], carbon monoxide [CO], and sulfur dioxide [SO2]) were available for the entire study period (1 January 1993 to 31 August 2000); detailed measurements of particulate matter were available for 25 months. We obtained data on 4 million emergency department visits from 31 hospitals in Atlanta. Visits for asthma, chronic obstructive pulmonary disease, upper respiratory infection, and pneumonia were assessed in relation to air pollutants using Poisson generalized estimating equations. RESULTS: In single-pollutant models examining 3-day moving averages of pollutants (lags 0, 1, and 2): standard deviation increases of ozone, NO2, CO, and PM10 were associated with 1-3% increases in URI visits; a 2 microg/m increase of PM2.5 organic carbon was associated with a 3% increase in pneumonia visits; and standard deviation increases of NO2 and CO were associated with 2-3% increases in chronic obstructive pulmonary disease visits. Positive associations persisted beyond 3 days for several of the outcomes, and over a week for asthma. CONCLUSIONS: The results of this study contribute to the evidence of an association of several correlated gaseous and particulate pollutants, including ozone, NO2, CO, PM, and organic carbon, with specific respiratory conditions.     

Traffic-related air pollution and childhood respiratory symptoms, function and allergies

BACKGROUND: Urban air pollution can trigger asthma symptoms in children, but there is conflicting evidence on effects of long-term exposure on lung function, onset of airway disease and allergic sensitization. METHODS: The spatial distribution of nitrogen oxides from traffic (traffic-NOx) and inhalable particulate matter from traffic (traffic-PM10) in the study area was assessed with emission databases and dispersion modeling. Estimated levels were used to assign first-year exposure levels for children in a prospective birth cohort (n = 4089), by linking to geocoded home addresses. Parents in 4 Swedish municipalities provided questionnaire data on symptoms and exposures when the children were 2 months and 1, 2, and 4-year-old. At 4 years, 73% of the children underwent clinical examination including peak expiratory flow and specific IgE measurements. RESULTS: Exposure to air pollution from traffic during the first year of life was associated with an excess risk of persistent wheezing (odds ratio [OR] for 44 microg/m3 [5th-95th percentile] difference in traffic-NOx = 1.60; 95% confidence interval [CI] = 1.09-2.36). Similar results were found for sensitization (measured as specific IgE) to inhalant allergens, especially pollen (OR for traffic-NOx = 1.67; 95% CI = 1.10-2.53), at the age of 4 years. Traffic-related air pollution exposure during the first year of life was also associated with lower lung function at 4 years of age. Results were similar using traffic-NOx and traffic-PM10 as indicators. CONCLUSIONS: Exposure to moderate levels of locally emitted air pollution from traffic early in life appears to influence the development of airway disease and sensitization in preschool children.     

温度在北京市空气污染中对循环、呼吸系统疾病急诊影响的修饰效应

目的 分析温度在空气污染短期暴露对循环、呼吸系统疾病急诊影响的修饰效应。方法 2010-2011年北京市循环系统和呼吸系统疾病逐日急诊资料,气象监测数据及空气污染指数（API）资料均来源于国家人口与健康科学数据共享平台。将日均温度进行分层,建立分层的时间序列模型。结果 循环系统、呼吸系统疾病急诊人数P₅₀分别为210和80例,API的P₅₀为76,日均温度P₅₀为14.2℃;空气污染对循环系统疾病急诊影响当天（lag0）即表现出效应最大值。空气污染对呼吸系统疾病急诊的影响在滞后第5天（lag5）时达到效应最高值。API对循环系统疾病急诊的影响在超低温（日均气温<-4.9℃）时效应出现最大值,即API每升高10个单位,RR值（95%CI）达到1.067（1.054~1.080）;API对呼吸系统疾病急诊的影响在高温（日均气温为24.4~28.5℃）及超高温时（日均气温>28.5℃）有明显增加,API每升高10个单位,RR值分别为1.021（95%CI：1.015~1.028）、1.006（95%CI：1.003~1.008）。结论 温度在空气污染与循环系统、呼吸系统疾病的关系中存在修饰效应。     

上海市大气污染与居民每日死亡关系的病例交叉研究

目的 以病例交叉的研究方法，估计大气污染急性暴露对上海市居民每日死亡的影响，并探讨该设计用于大气污染急性健康效应研究的可行性。方法 采用病例交叉设计的方法分析上海市2000年6月1日至2001年12月31日大气污染与居民每日总死亡和分疾病别死亡的关系，同时比较双向对照设计和单向回顾性对照设计研究结果的差异。结果 采用不同的对照选择方案，病例交叉设计的研究结果变化较大；采用双向1：6的对照设计，大气可吸入颗粒物(PMl0)、二氧化硫(SO2)、二氧化氮(NO2)48h平均浓度每增加10μg／m^3，上海市城区居民总死亡发生的相对危险度分别为1．003(95％CI：1．001～1．005)、1．016(95％CI：1．011～1．021)、1．020(95％CI：1．012～1．027)。结论 上海市城区目前的PMl0、SO2、NO2水平对居民死亡确有影响；病例交叉设计是一种研究大气污染急性健康效应的有效工具。     

A case-crossover study of wintertime ambient air pollution and infant bronchiolitis

We examined the association of infant bronchiolitis with acute exposure to ambient air pollutants. DESIGN: We employed a time-stratified case-crossover method and based the exposure windows on a priori, biologically based hypotheses. PARTICIPANTS: We evaluated effects in 19,901 infants in the South Coast Air Basin of California in 1995-2000 with a hospital discharge record for bronchiolitis in the first year of life (International Classification of Diseases, 9th Revision, CM466.1). EVALUATIONS/MEASUREMENTS: Study subjects' ZIP code was linked to ambient air pollution monitors to derive exposures. We estimated the risk of bronchiolitis hospitalization associated with increases in wintertime ambient air pollutants using conditional logistic regression. RESULTS: We observed no increased risk after acute exposure to particulate matter < or = 2.5 microm in aerodynamic diameter (PM2.5), carbon monoxide, or nitrogen dioxide. PM2.5 exposure models suggested a 26-41% increased risk in the most premature infants born at gestational ages between 25 and 29 weeks; however, these findings were based on very small numbers. CONCLUSIONS: We found little support for a link between acute increases in ambient air pollution and infant bronchiolitis except modestly increased risk for PM2.5 exposure among infants born very prematurely. In these infants, the periods of viral acquisition and incubation concurred with the time of increased risk. RELEVANCE TO PROFESSIONAL PRACTICE: We present novel data for the infant period and the key respiratory disease of infancy, bronchiolitis. Incompletely explained trends in rising bronchiolitis hospitalization rates and increasing number of infants born prematurely underscore the importance of evaluating the impact of ambient air pollution in this age group in other populations and studies.     

Association between air pollution and ischemic cardiovascular emergency room visits

This study observed the relationship between air pollutants and ischemic cardiac diseases such as angina and acute myocardial infarction in a representative cardiovascular center emergency room in São Paulo, Brazil. Daily emergency room admissions to the Institute of the Heart of the University of São Paulo, as well as data concerning daily air pollutant levels and meteorological variables, were collected from January 1994 to August 1995. Generalized additive Poisson regressions were fitted to the logarithm of the expected values of total emergency room visits due to angina or acute myocardial infarction, controlling for smooth functions of season and weather and indicators for days of the week. All investigated pollutants were positively associated with ischemic cardiovascular disease emergency room visits, and the time lags were relatively short, but only CO presented an effect that was statistically significant. An interquartile range increase in CO was associated with an increase of 6.4% (95% CI: 0.7-12.1) in daily angina or acute myocardial infarction emergency room visits. This result did not change when estimates were done using linear models and natural cubic splines. This study showed that air pollution has a role in cardiovascular morbidity in São Paulo, reinforcing the necessity for air pollutant emission-controlling polices in urban areas.     

Air pollution and emergency admissions in Boston, MA

STUDY OBJECTIVE: Many studies have shown that ambient particulate air pollution (PM) is associated with increased risk of hospital admissions and deaths for cardiovascular or respiratory causes around the world. In general these have been analysed in association with PM(10) and ozone, whereas PM(2.5) is now the particle measure of greatest health and regulatory concern. And little has been published on associations of hospital admissions and PM components. DESIGN: This study analysed hospital admissions for myocardial infarction (15 578 patients), and pneumonia (24 857 patients) in associations with fine particulate air pollution, black carbon (BC), ozone, nitrogen dioxide (NO(2)), PM not from traffic, and carbon monoxide (CO) in the greater Boston area for the years 1995-1999 using a case-crossover analysis, with control days matched on temperature. MAIN RESULTS: A significant association was found between NO(2) (12.7% change (95% CI: 5.8, 18)), PM(2.5) (8.6% increase (95% CI: 1.2, 15.4)), and BC (8.3% increase (95% CI: 0.2, 15.8)) and the risk of emergency myocardial infarction hospitalisation; and between BC (11.7% increase (95% CI: 4.8, 17.4)), PM(2.5) (6.5% increase (95% CI: 1.1, 11.4)), and CO (5.5% increase (95% CI: 1.1, 9.5)) and the risk of pneumonia hospitalisation. CONCLUSIONS: The pattern of associations seen for myocardial infarction and pneumonia (strongest associations with NO(2), CO, and BC) suggests that traffic exposure is primarily responsible for the association with heart attacks.     

Fine particulate air pollution and its components in association with cause-specific emergency admissions

Background  

Although the association between exposure to particulate matter and health is well established, there remains uncertainty as to whether certain chemical components are more harmful than others. We explored whether the association between cause-specific hospital admissions and PM_2.5 was modified by PM_2.5 chemical composition.