Walters S, Phupinyokul M, Ayres J
Department of Public Health and Epidemiology, University of Birmingham Medical School, UK.
Thorax. 1995 Sep;50(9):948-54. doi: 10.1136/thx.50.9.948.
A study was undertaken to determine the relationship between hospital admissions for asthma and all respiratory conditions in electoral wards in the West Midlands and ambient levels of smoke, sulphur dioxide, and nitrogen dioxide, and to establish whether the relationship is independent of social deprivation and ethnicity, and is different for young children and older individuals.
Data on hospital admissions for acute respiratory conditions were obtained by electoral ward from the West Midlands Regional Health Authority Information Department Körner inpatient data including asthma (ICD 493) and all acute respiratory disease (466, 480-486, 490-496) for the period April 1988 to March 1990. The population for each electoral ward, percentage of ward population that was from non-white ethnic groups, and Townsend deprivation score were all calculated from 1991 census information. Data on smoke and sulphur dioxide (SO2) levels were obtained for 24 wards in Birmingham, Coventry, Wolverhampton, Dudley, Stafford, and Burton-on-Trent, and on nitrogen dioxide (NO2) levels from 39 wards in the same local authority areas. All were background urban sites and most participated in the Warren Spring national quality control programme for SO2 and smoke monitoring. Indirect age-sex standardised hospitalisation rates (SHR) for all respiratory conditions and asthma were calculated using the 1991 rates for the West Midlands RHA as the standard. Multivariate regression models were used to assess the relationship between individual pollutants and the SHR. The Townsend score and percentage of the population from non-white ethnic groups were included in all models to adjust for ethnicity and socioeconomic deprivation.
The SHR for asthma varied almost fourfold across the region, and all respiratory SHR showed more than three fold variation. Bivariate regression revealed both Townsend score and percentage of non-white individuals to be associated with SHR for asthma and all respiratory conditions at all ages, but not for children under 5 years. NO2 was associated with hospital admission rates for all ages including children under 5. SO2 and smoke were not associated with hospital admissions. Multivariate analysis including Townsend score and percentage of non-white subjects in the model revealed that NO2 was associated with hospital admission rates for all respiratory conditions only for children under 5. The Townsend score was associated with SHR for all respiratory conditions, and both the Townsend score and percentage of non-white subjects were associated with SHR for asthma in children under 5 in two of three models. The association between SHR for asthma and percentage of non-white subjects was negative.
Socioeconomic deprivation, as measured by the Townsend score, is a significant predictor of hospital admission rates for respiratory disease in older individuals, and both the percentage of non-white subjects and the Townsend score are significant predictors of hospital admission rates for asthma in children. After correction for socioeconomic deprivation and ethnicity, background urban NO2 levels in the ward of residence are significantly associated with standardised hospital admission rates for all respiratory disease in children under 5. This may represent a causal effect of NO2 on the respiratory health of children, or the effect of confounding factors not corrected by use of the Townsend score.
开展了一项研究，以确定西米德兰兹郡选举区哮喘及所有呼吸道疾病的住院情况与环境中的烟雾、二氧化硫和二氧化氮水平之间的关系，并确定这种关系是否独立于社会剥夺和种族因素，以及对于幼儿和年长个体是否有所不同。
通过选举区从西米德兰兹郡地区卫生局信息部获取急性呼吸道疾病的住院数据，包括1988年4月至1990年3月期间的哮喘（国际疾病分类493）和所有急性呼吸道疾病（466、480 - 486、490 - 496）的科纳住院患者数据。每个选举区的人口、非白人种族群体在选区人口中的百分比以及汤森德剥夺分数均根据1991年人口普查信息计算得出。获取了伯明翰、考文垂、伍尔弗汉普顿、达德利、斯塔福德和特伦特河畔伯顿24个选区的烟雾和二氧化硫（SO₂）水平数据，以及同一地方当局区域内39个选区的二氧化氮（NO₂）水平数据。所有均为城市背景监测点，且大多数参与了沃伦泉国家二氧化硫和烟雾监测质量控制计划。使用西米德兰兹郡地区卫生局1991年的发病率作为标准，计算所有呼吸道疾病和哮喘的间接年龄 - 性别标准化住院率（SHR）。采用多变量回归模型评估个体污染物与SHR之间的关系。所有模型均纳入汤森德分数和非白人种族群体的百分比，以调整种族和社会经济剥夺因素。
整个地区哮喘的SHR差异近四倍，所有呼吸道疾病的SHR差异超过三倍。双变量回归显示，汤森德分数和非白人个体的百分比在各年龄段均与哮喘及所有呼吸道疾病的SHR相关，但5岁以下儿童除外。二氧化氮与各年龄段包括5岁以下儿童的住院率相关。二氧化硫和烟雾与住院情况无关。模型中纳入汤森德分数和非白人受试者百分比的多变量分析显示，二氧化氮仅与5岁以下儿童所有呼吸道疾病的住院率相关。汤森德分数与所有呼吸道疾病的SHR相关，在三个模型中的两个模型中，汤森德分数和非白人受试者的百分比均与5岁以下儿童哮喘的SHR相关。哮喘的SHR与非白人受试者百分比之间的关联为负。
以汤森德分数衡量的社会经济剥夺是年长个体呼吸道疾病住院率的重要预测因素，非白人受试者的百分比和汤森德分数均是儿童哮喘住院率的重要预测因素。在校正社会经济剥夺和种族因素后，居住选区的城市背景二氧化氮水平与5岁以下儿童所有呼吸道疾病的标准化住院率显著相关。这可能代表二氧化氮对儿童呼吸道健康的因果效应，或使用汤森德分数未校正的混杂因素的效应。
