Lancet Respir Med. 2017 Sep;5(9):691-706. doi: 10.1016/S2213-2600(17)30293-X. Epub 2017 Aug 16.
Chronic obstructive pulmonary disease (COPD) and asthma are common diseases with a heterogeneous distribution worldwide. Here, we present methods and disease and risk estimates for COPD and asthma from the Global Burden of Diseases, Injuries, and Risk Factors (GBD) 2015 study. The GBD study provides annual updates on estimates of deaths, prevalence, and disability-adjusted life years (DALYs), a summary measure of fatal and non-fatal disease outcomes, for over 300 diseases and injuries, for 188 countries from 1990 to the most recent year.
We estimated numbers of deaths due to COPD and asthma using the GBD Cause of Death Ensemble modelling (CODEm) tool. First, we analysed data from vital registration and verbal autopsy for the aggregate category of all chronic respiratory diseases. Subsequently, models were run for asthma and COPD relying on covariates to predict rates in countries that have incomplete or no vital registration data. Disease estimates for COPD and asthma were based on systematic reviews of published papers, unpublished reports, surveys, and health service encounter data from the USA. We used the Global Initiative of Chronic Obstructive Lung Disease spirometry-based definition as the reference for COPD and a reported diagnosis of asthma with current wheeze as the definition of asthma. We used a Bayesian meta-regression tool, DisMod-MR 2.1, to derive estimates of prevalence and incidence. We estimated population-attributable fractions for risk factors for COPD and asthma from exposure data, relative risks, and a theoretical minimum exposure level. Results were stratified by Socio-demographic Index (SDI), a composite measure of income per capita, mean years of education over the age of 15 years, and total fertility rate.
In 2015, 3·2 million people (95% uncertainty interval [UI] 3·1 million to 3·3 million) died from COPD worldwide, an increase of 11·6% (95% UI 5·3 to 19·8) compared with 1990. There was a decrease in age-standardised death rate of 41·9% (37·7 to 45·1) but this was counteracted by population growth and ageing of the global population. From 1990 to 2015, the prevalence of COPD increased by 44·2% (41·7 to 46·6), whereas age-standardised prevalence decreased by 14·7% (13·5 to 15·9). In 2015, 0·40 million people (0·36 million to 0·44 million) died from asthma, a decrease of 26·7% (-7·2 to 43·7) from 1990, and the age-standardised death rate decreased by 58·8% (39·0 to 69·0). The prevalence of asthma increased by 12·6% (9·0 to 16·4), whereas the age-standardised prevalence decreased by 17·7% (15·1 to 19·9). Age-standardised DALY rates due to COPD increased until the middle range of the SDI before reducing sharply. Age-standardised DALY rates due to asthma in both sexes decreased monotonically with rising SDI. The relation between with SDI and DALY rates due to asthma was attributed to variation in years of life lost (YLLs), whereas DALY rates due to COPD varied similarly for YLLs and years lived with disability across the SDI continuum. Smoking and ambient particulate matter were the main risk factors for COPD followed by household air pollution, occupational particulates, ozone, and secondhand smoke. Together, these risks explained 73·3% (95% UI 65·8 to 80·1) of DALYs due to COPD. Smoking and occupational asthmagens were the only risks quantified for asthma in GBD, accounting for 16·5% (14·6 to 18·7) of DALYs due to asthma.
Asthma was the most prevalent chronic respiratory disease worldwide in 2015, with twice the number of cases of COPD. Deaths from COPD were eight times more common than deaths from asthma. In 2015, COPD caused 2·6% of global DALYs and asthma 1·1% of global DALYs. Although there are laudable international collaborative efforts to make surveys of asthma and COPD more comparable, no consensus exists on case definitions and how to measure disease severity for population health measurements like GBD. Comparisons between countries and over time are important, as much of the chronic respiratory burden is either preventable or treatable with affordable interventions.
Bill & Melinda Gates Foundation.
慢性阻塞性肺疾病（COPD）和哮喘是具有全球异质性分布的常见疾病。在这里，我们展示了来自全球疾病、伤害和危险因素研究（GBD）2015 年研究的 COPD 和哮喘的方法和疾病及风险估计。GBD 研究每年都会提供关于 188 个国家 1990 年至最近一年的死亡、患病率和残疾调整生命年（DALY）的估计数，DALY 是一个综合的致命和非致命疾病结果的衡量标准。
我们使用 GBD 死因综合模型（CODEm）工具来估计 COPD 和哮喘的死亡人数。首先，我们分析了来自生命登记和口头尸检的所有慢性呼吸道疾病的综合数据。随后，我们针对哮喘和 COPD 运行模型，依靠协变量来预测那些生命登记数据不完整或没有的国家的发病率。COPD 和哮喘的疾病估计是基于已发表文献的系统综述、未发表报告、调查以及来自美国的卫生服务就诊数据。我们使用基于全球倡议慢性阻塞性肺疾病（GOLD）肺量计的定义作为 COPD 的参考，以及当前喘息的报告诊断作为哮喘的定义。我们使用贝叶斯元回归工具 DisMod-MR 2.1 来推导患病率和发病率的估计值。我们从暴露数据、相对风险和理论最低暴露水平中为 COPD 和哮喘的危险因素确定了人群归因分数。结果按社会人口指数（SDI）分层，SDI 是一个综合衡量人均收入、15 岁以上平均受教育年限和总生育率的指标。
2015 年，全球有 320 万人（95%置信区间[UI]310 万至 330 万）死于 COPD，与 1990 年相比增加了 11.6%（5.3%至 19.8%）。年龄标准化死亡率下降了 41.9%（37.7%至 45.1%），但被全球人口的增长和老龄化所抵消。1990 年至 2015 年，COPD 的患病率增加了 44.2%（41.7%至 46.6%），而年龄标准化患病率下降了 14.7%（13.5%至 15.9%）。2015 年，全球有 40 万人（36 万至 44 万）死于哮喘，比 1990 年下降了 26.7%（7.2%至 43.7%），年龄标准化死亡率下降了 58.8%（39.0%至 69.0%）。哮喘的患病率增加了 12.6%（9.0%至 16.4%），而年龄标准化患病率下降了 17.7%（15.1%至 19.9%）。COPD 的年龄标准化 DALY 率在 SDI 的中间范围之前持续增加，然后急剧下降。男女哮喘的年龄标准化 DALY 率随着 SDI 的升高而单调下降。哮喘与 SDI 的 DALY 率之间的关系归因于丧失生命年（YLL）的变化，而 COPD 的 DALY 率则因 YLL 和残疾生活年在 SDI 连续体上的变化而相似。吸烟和大气颗粒物是 COPD 的主要危险因素，其次是室内空气污染、职业性颗粒物、臭氧和二手烟。这些风险共同解释了 COPD 导致的 73.3%（65.8%至 80.1%）的 DALY。吸烟和职业性哮喘致敏原是 GBD 中唯一量化的哮喘风险因素，占哮喘导致的 DALY 的 16.5%（14.6%至 18.7%）。
2015 年，哮喘是全球最常见的慢性呼吸道疾病，其病例数是 COPD 的两倍。COPD 的死亡人数是哮喘的 8 倍。2015 年，COPD 导致全球 2.6%的 DALY，哮喘导致全球 1.1%的 DALY。尽管有值得称赞的国际合作努力，使哮喘和 COPD 的调查更加可比，但在病例定义和如何衡量人口健康测量（如 GBD）中的疾病严重程度方面，尚未达成共识。国家之间和时间上的比较很重要，因为大部分慢性呼吸道负担是可以预防或用负担得起的干预措施治疗的。
比尔及梅琳达·盖茨基金会。
