Interactions between particulate air pollution and temperature in air pollution mortality time series studies

In many community time series studies on the effect of particulate air pollution on mortality, particulate air pollution is modeled additively. In this study, we investigated the interaction between daily particulate air pollution and daily mean temperature in Cook County, Illinois and Allegheny County, Pennsylvania, using data for the period 1987-1994. This was done through the use of joint particulate air pollution-temperature response surfaces and by stratifying the effect of particulate air pollution on mortality by temperature. Evidence that the effect of particulate air pollution on mortality may depend on temperature is found. However, the results were sensitive to the number of degrees of freedom used in the confounder adjustments, the particulate air pollution exposure measure, and how the effects of temperature on mortality are modeled. The results were less sensitive to the estimation method used--generalized linear models and natural cubic splines or generalized additive models and smoothing splines. The results of this study suggest that in community particulate air pollution mortality time series studies the possibility of an interaction between daily particulate air pollution and daily mean temperature should be considered.     

我国空气污染物与人群呼吸系统疾病死亡急性效应的Meta分析

目的 回顾我国空气污染与呼吸系统疾病健康效应的研究, 定量分析空气污染物[空气动力学直径<2.5 μm的细颗粒物(PM_2.5)和<10 μm的可吸入颗粒物(PM₁₀)、二氧化硫(SO₂)、二氧化氮(NO₂)和臭氧(O₃)]与人群呼吸系统疾病急性死亡的关系。方法 系统收集1989-2014年在PubMed、SpringerLink、Embase、Medline、中国期刊全文数据库、中国生物医学文献数据库和维普中文科技期刊全文数据库公开发表的有关我国空气污染与呼吸系统疾病健康效应的研究文献, 总结该类研究在我国各省份的覆盖情况;并依据Meta分析法分别对PM₁₀、PM_2.5、NO₂、SO₂和O₃与人群呼吸系统疾病急性死亡关系的定量研究进行分析, 采用Stata 12.0软件进行异质性分析后利用固定或随机效应模型合并效应值, 并检验发表偏倚。结果 共收集到有关空气污染与人群呼吸系统疾病健康效应的研究文献157篇, 覆盖我国79.4%的省份。Meta分析结果显示, PM₁₀、PM_2.5、NO₂、SO₂和O₃浓度每上升10 μg/m³, 人群呼吸系统疾病死亡率分别增加0.50%(95%CI: 0~0.90%)、0.50%(95%CI: 0.30%~0.70%)、1.39%(95%CI: 0.90%~1.78%)、1.00%(95%CI: 0.40%~1.59%)和0.10%(95%CI: -1.21%~1.39%), 各研究均未发现明显发表偏倚。结论 我国PM₁₀、PM_2.5、NO₂、SO₂浓度的上升均会导致人群呼吸系统疾病急性死亡的增加。     

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.     

大气二氧化硫与居民每日呼吸系统疾病死亡相关性的时间序列分析

目的 分析大气中主要气态污染物二氧化硫(SO2)急性暴露对北京市居民每日呼吸系统疾病死亡人数的影响.方法 采用时间序列的广义相加模型,在控制时间趋势和气象因素、“星期几效应”等混杂因素的基础上,分析北京市2006年1月1日2009年12月31日大气SO2浓度与居民每日呼吸系统疾病死亡人数的关系.结果 北京市大气SO2浓度每升高10 μg/m3,居民当日呼吸系统疾病死亡人数、滞后1d的每日肺炎死亡人数分别增加0.88％(95％CI:0.34％～1.41％)和1.43％(95％CI:0.51％～2.35％).结论 北京市大气SO2污染与居民每日呼吸系统疾病死亡人数和肺炎死亡人数有统计学关联.     

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…     

合肥市大气污染与肺炎门诊量的时间序列研究

目的探讨大气污染物SO_2、NO_2和PM_(2.5)浓度与合肥市滨湖医院肺炎日门诊量之间的关系。方法采用时间序列分析的广义相加Poisson回归模型,在控制长期趋势、星期几效应和气象因素等混杂因素的影响后,定量分析2014年安徽省合肥市大气污染物SO_2、NO_2、PM_(2.5)日均浓度与滨湖医院肺炎日门诊量的关系及滞后效应。结果单污染物模型中,在控制了长期趋势、星期几效应和气象因素的影响后,SO_2在滞后3、4、5 d(lag3、lag4、lag5)时对肺炎日门诊量的影响有统计学意义(P0.05),NO_2滞后2、3、4、5 d(lag2、lag3、lag4、lag5)时的影响有统计学意义(P0.01),PM_(2.5)滞后3、4 d(lag3、lag4)时的影响有统计学意义(P0.05);SO_2、NO_2、PM_(2.5)的滞后效应分别在lag3、lag2、lag4时最明显,当SO_2、NO_2、PM_(2.5)浓度每升高10μg/m~3时,肺炎日门诊量分别增加1.54%(95%CI:0.28%~2.81%),1.98%(95%CI:0.89%~3.08%)和0.28%(95%CI:0.06%~0.50%)。多污染物模型中,当模型中引入两种或两种以上的污染物后,各污染物对肺炎日门诊量的效应估计值均较单污染物模型降低,但并不改变各污染物与肺炎日门诊量之间的正向关联。结论合肥市大气污染物SO_2、NO_2、PM_(2.5)浓度升高可能引起医院肺炎日门诊量增加,且有一定的滞后效应。     

Difference in the relation between daily mortality and air pollution among elderly and all-ages populations in southwestern France

Numerous time series studies around the world have reported an association between mortality and particulate air pollution. We investigated the distribution over time of effect of air pollution on short-term mortality among subjects aged 65 years and older and of all ages in Bordeaux, France. Statistical analysis was based on generalized additive models using either loess or penalized spline smoothing. Our study found a significant positive association between air pollution and all nonaccidental mortality and specific mortality in both group of population (all ages and elderly) with a greater effect among the elderly, particularly for respiratory mortality. For this case, we observed a greater effect according to distributed lag models (0-5 days) among the elderly, with an estimated increase of 9.2% in the daily number of deaths for 10 microg/m(3) of daily black smoke [95% CI, 3.4-15.3]. These results contribute to the efforts made to understand how air pollution promotes adverse health effects and to identify susceptible subgroups.     

济南市空气污染对呼吸系统疾病门诊量的影响

目的探讨空气污染对济南市某医院呼吸系统疾病的短期影响及在人群中的差异。方法收集济南市某医院2010年1月1日至2012年12月31日呼吸系统疾病门诊资料、同期气象及空气污染数据,采用分布滞后非线性模型和温度分层等方法研究空气污染的滞后效应及其与气温的交互作用。结果空气污染当日即可引起呼吸系统门诊量升高,且效应可持续18 d;空气污染指数每升高10时,14 d累积效应可使呼吸系统门诊量增加4.26%(95%CI:1.89%~6.69%);将日最高气温按照P10和P90分为低、中、高3个水平后,空气污染指数每升高10可使呼吸系统疾病门诊量分别增加0.24%(95%CI:-4.65%~5.39%),2.54%(95%CI:0.55%~4.57%)和11.24%(95%CI:4.69%~18.20%),其中高温与空气污染的交互作用有统计学意义(P0.05),且在0~14岁人群中效应更明显。结论空气污染加重会导致呼吸系统疾病门诊人数升高且持续时间较长,并与高温有交互作用。提示高温天气时更应加强对空气污染的防护,尤其应关注儿童等脆弱人群。     

太原市空气污染对小学生呼吸系统症状的急性影响

目的 了解太原市重工业造成的空气污染对儿童呼吸系统症状的急性影响,探讨儿童呼吸系统症状与空气污染的相关性.方法 于2008年7月1日-2009年6月30日以定群研究方法选择479名6～11岁儿童,通过填写小学生健康日志来记录每日呼吸系统症状.同时收集距学校1.5 km处空气监测点PM10、SO2、NO2、CO日均浓度.应用广义估计方程(GEE)建立空气污染与小学生呼吸系统症状的剂量反应关系,估计污染物危险度.结果 调整了个体水平的危险因素之后,SO2影响的估计值稳定.在滞后效应中,lag1～lag 3和lag 5危险度相对较高,SO2浓度每升高1个四分位数间距(63 μg/m3),儿童呼吸系统症状增加8％～17％.在累积效应中,危险度随累积天数的增加而上升,SO2浓度每升高1个四分位数间距,儿童呼吸系统症状增加25％～74％.累积效应大于滞后效应.调整了其他污染物的影响之后,SO2的危险度略有升高,分析结果仍有统计学意义.结论 大气SO2污染可能导致本次调查的小学生呼吸系统症状发生率上升.     

Wildfire air pollution and daily mortality in a large urban area

Unusual air pollution episodes, such as when smoke from wildfires covers a large urban area, can be used to attempt to detect associations between short-term increases in particulate matter (PM) concentrations and subsequent mortality without relying on the sophisticated statistical models that are typically required in the absence of such episodes. The objective of this study was to explore whether acute increases in PM concentrations from wildfire smoke cause acute increases in daily mortality. The temporal patterns of daily nonaccidental deaths and daily cardiorespiratory deaths for June of 2002 in the Denver metropolitan area were examined and compared to those in two nearby counties in Colorado that were not affected by the wildfire smoke and to daily deaths in Denver in June of 2001. Abrupt increases in PM concentrations in Denver occurred on 2 days in June of 2002 as a result of wildfire smoke drifting over the Denver area. Small peaks in mortality corresponded to both of the PM peaks, but the first mortality peak also corresponded to a peak of mortality in the control counties, and cardiorespiratory deaths began to increase on the day before the second peak. Further, there was no detectable increase in cardiorespiratory deaths in the hours immediately following the PM peaks. Although the findings from this study do not rule out the possibility of small increases in mortality due to abrupt and dramatic increases in PM concentrations from wildfire smoke, in a population of over 2 million people no perceptible increases in daily mortality could be attributed to such events.     

兰州市城关区大气污染对儿童呼吸系统疾病和症状的影响

目的了解兰州市城关区大气污染对儿童呼吸系统疾病和症状的影响。方法于2013年9—11月,采用随机整群抽样的方法抽取兰州市城关区和榆中县的2 016名学龄期儿童(城关区1 087名,榆中县929名)为研究对象,采用美国流行病学标准问卷(ATS-DLD-78-C)进行呼吸系统疾病和症状发生情况调查。结果 2013年城关区大气SO2、NO2、PM2.5、PM10日均浓度均高于榆中县,差异有统计学意义(P0.05)。城关区儿童感冒时咳嗽、不感冒时咳嗽、感冒时咯痰、不感冒时咯痰、鼻炎、支气管炎、肺炎、哮喘等8种呼吸系统疾病和症状的发病危险性分别是榆中县的1.563、1.606、2.055、1.849、2.786、2.514、1.976、2.599倍,均有统计学意义(P0.05)。采用多因素logistic回归分析调整年龄、厨房燃料、冬季采暖方式等混杂因素后,与榆中县比较,城关区儿童感冒时咳嗽、不感冒时咳嗽、感冒时咯痰、鼻炎、支气管炎、肺炎等疾病和症状发生的危险性均较高,OR值(95%CI)分别为1.571(1.273~1.938),1.568(1.028~2.391),2.026(1.580~2.597),2.136(1.430~3.192),2.142(1.463~3.136),1.741(1.190~2.548),均有统计学意义(P0.05)。结论城关区儿童部分呼吸系统疾病和症状发生率高于榆中县,可能与城关区大气污染有关。     

Trends in relative risk estimates for the association between air pollution and mortality in The Netherlands, 1992-2006

Background

Daily variations in the levels of air pollution are well known to be associated with daily variations in mortality counts. Given the large number of time-series studies, there is little need for simple replication of these results in additional locations. However, additional analyses of time-series data might be useful in elucidating remaining questions on the role of air pollution on mortality.

Objectives

Because of ongoing issues related to causality, changing toxicity, the difficulty in isolating the independent effects of individual pollutants, the availability of new methods to detect effect thresholds, and questions about the extent to which effects are restricted to frail members of the population, additional analyses of time-series data might be helpful in addressing these issues. We show an example where additional time-series analyses can be helpful in elucidating specific questions in the field of air pollution epidemiology.

Methods

We analysed daily mortality and air pollution data using Poisson regression in generalised additive models. Air pollution data for the overall period 1992–2006 and for four different periods were analysed to assess the overall risk estimates for the whole period and to assess variability over time for the different effect estimates.

Results and Conclusion

We found some statistically significant upward trends, but this was only the case for a few associations without a consistent pattern over the cause-specific deaths. Whether these findings are consistent over time or whether our findings are merely the result of statistical chance can only be elucidated by continuation of monitoring of the relative risks over time in the future. Although these results may indicate that both photochemical and particulate matter air pollution might have become more toxic, the lack of a clear pattern in the results makes these conclusions speculative.     

天津市大气污染对儿童呼吸系统疾病影响的病例交叉研究

目的  探求大气污染对天津市儿童呼吸系统疾病的影响,为疾病的预防与控制提供依据。 方法  利用单污染物和多污染物条件Logistic回归模型,来估计空气污染物浓度和儿童呼吸系统疾病发病之间的关系。 结果  单污染物条件Logistic回归模型显示,大气中NO₂、PM_2.5、PM₁₀、CO的超额危险度(excess risk rate,ER)及其95%CI分别为2.823%(2.581~3.065)、0.476%(0.382~0.569)、0.437%(0.368~0.506)、22.263%(15.449~29.478)。多污染物条件Logistic回归分析显示：在寒冷季节,NO₂暴露对儿童呼吸系统疾病的影响效应最大,ER及其95%CI为7.395%(6.595~8.202)。 结论  NO₂、PM₁₀、PM_2.5、CO日平均浓度的升高可以增高儿童呼吸系统疾病的发生风险。     

Synoptic weather patterns and modification of the association between air pollution and human mortality

To assess whether meteorological conditions modify the relationship between short-term exposure to ambient air pollution and mortality, an examination of air pollution and human mortality associations (ecologic) using hybrid spatial synoptic classification procedures was conducted. Concentrations of air pollutants and human mortality from all non-accidental and cardiorespiratory causes were examined according to typical winter and summer synoptic climatologies in Toronto, Canada, between 1981 and 1999. Air masses were derived using a hybrid spatial synoptic classification procedure associating each day over the 19-year period with one of six different typical weather types, or a transition between two weather types. Generalized linear models (GLMs) were used to assess the risk of mortality from air pollution within specific air mass type subsets. Mortality follows a distinct seasonal pattern with a maximum in winter and a minimum in summer. Average air pollution concentrations were similar in both seasons with the exception of elevated sulfur dioxide levels in winter and elevated ozone levels in summer. Subtle changes in meteorological composition can alter the strength of pollutant associations with health outcomes, especially in the summer season. Although there does not appear to be any systematic patterning of modification, variation in pollutant concentrations seems dependent on the type of synoptic category present.     

Association of daily cause-specific mortality with ambient particle air pollution in Wuhan, China

In Asia, limited literature has been published on the association between daily mortality and ambient air pollution. We examined the associations of daily cause-specific mortality with daily mean concentrations of particulate matter (PM) with a mass median aerodynamic diameter less than 10 microm (PM(10)) in Wuhan, China using 4 years of data (2001-2004). There are approximately 4.5 million residents in Wuhan who live in the city core area of 201 km(2) where air pollution levels are higher and pollution ranges are wider than the majority of cities in the published literature. We use quasi-likelihood estimation within the context of the generalized additive models (GAMs) (natural spline (NS) models in R) to model the natural logarithm of the expected daily death counts as a function of the predictor variables. We found consistent PM(10) effects on mortality with the strongest effects on lag 0 day. Every 10 microg/m(3) increase in PM(10) daily concentration at lag 0 day was significantly associated with an increase in non-accidental (0.36%; 95% CI 0.19-0.53%), cardiovascular (0.51%; 95% CI 0.28-0.75%), stroke (0.44%; 95% CI 0.16-0.72%), cardiac (0.49%; 95% CI 0.08-0.89%), respiratory (0.71%; 95% CI 0.20-1.23%), and cardiopulmonary (0.46%; 95% CI 0.23-0.69%). In general, these effects were stronger among the elderly (65 years > or = 45 years) than among the young. The exploration of exposure-response relationships between PM(10) and cause-specific mortality suggests the appropriateness of assuming linear relationships, where the PM(10) concentration in Wuhan ranged from 24.8 to 477.8 microg/m(3). We conclude that there is consistent evidence of acute effects of PM(10) on cardiopulmonary mortality. A linear no threshold exposure-response relationship is suggested between PM(10) and the studied cause-specific mortality.     

北京市大气污染与城区居民死亡率关系的时间序列分析

为定量评价北京市大气污染对居民每日疾病死亡率的影响 ,运用时间 -序列分析方法 ,控制了流感、季节等混杂因素的影响后 ,对北京市主要大气污染物CO、SO2 、NOX、TSP、PM10 与居民相应疾病死亡率的相关关系进行了定量评价。以呼吸系统疾病、循环系统疾病、冠心病、慢性阻塞性肺病和消化系统肿瘤疾病死亡人数分别为因变量 ,大气污染物浓度和平均温度、湿度为自变量 ,进行了泊松回归分析。单变量分析结果表明 ,除TSP对冠心病死亡率的影响无显著意义外 ,大气中CO、SO2 、NOX 、TSP浓度与呼吸系统、心脑血管疾病、慢性阻塞性肺病和冠心病死亡率之间的正相关关系均有显著意义 ,而多因素泊松回归得到的暴露 -反应关系模型显示 ,SO2 浓度每提高 10 0 μg m3,呼吸系统、循环系统、冠心病和慢性阻塞性肺病疾病死亡率分别增加 4 2 1%、3 97%、10 68%和 19 2 2 % ;总悬浮颗粒物每增加 10 0 μg m3 ,呼吸系统疾病死亡率增加 3 19% ,循环系统死亡率增加 0 62 %。提示大气污染物浓度的升高会引起相应疾病死亡率的增加     

Determining the threshold effect of ozone on daily mortality: an analysis of ozone and mortality in Seoul, Korea, 1995-1999

Many studies have shown a positive association between ambient ozone levels and mortality. Typically, these findings are based on models that assume a linear relationship between log mortality and ozone level. In this study, we adapted generalized additive models in which ozone effects are presumed to occur in three different ways: as a simple linear term, as a cubic natural spline term, and as a combination of two linear terms (a threshold model). We applied these models to daily time-series data for Seoul, Korea for the years 1995-1999 and found that the threshold model always fits best among the three. A 2.6% (95% CI: 1.7-3.5) increase of estimated relative risk (RR) in the total mortality associated with a 21.5 ppb increase of daily 1-h maximum ozone lagged by 1 day was observed by linear Poisson's regression. However, a 3.4% (95% CI: 2.3-4.4) increase in the estimated RR was observed using the threshold model. Adjustments for other ambient pollutants caused little changes to these results; 2.4-2.5% in the linear models and 3.2-3.4% in the threshold models. In addition, the largest difference in the estimated RRs of the linear and threshold models was observed in the summer: 1.9% (95% CI: 0.5-3.3) by the linear model and 3.8% (95% CI: 2.0-5.7) by the threshold model. These findings indicate that the conventional time-series Poisson regression model, which dose not take threshold into consideration, could underestimate the true risk of the ozone effect on daily mortality.     

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。     

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.     

Ozone air pollution and daily mortality in Genoa, Italy between 1993 and 1996

The association between ozone (O3) and daily mortality was investigated in Genoa, an Italian city characterized by a Mediterranean climate and a high prevalence of elderly inhabitants. The O3 effect, adjusted for long time trend, seasonality and weather, was assessed using Poisson regression modelling, allowing for overdispersion and autocorrelation, and expressed as mean variation percent of daily mortality per 50 microg/m3 increase (MV). Significant MVs for overall (+4.0%) and cardiovascular (+7.2%) mortality were detected at 1-day lag. The effects were stronger in the warmer season (May-October). Similar estimates were found after restricting the analyses to the elderly (>or=75 years). Furthermore, in this group, higher MVs were observed for total mortality at 2-day lag. A statistically significant synergistic effect between O3 and temperature was observed for cardiovascular mortality, particularly in elderly people, with an evident increase in mortality risk above 26 degrees C (MV +30.0% for the whole population and +40.0% for the elderly, respectively). This investigation highlights the importance of taking local climatic and demographic features into account when comparing different time-series studies, and substantiates the influence of photochemical pollution on mortality trends in small urban areas.