Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Department of Epidemiology and Public Health, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
BMJ Open. 2019 Mar 20;9(3):e023673. doi: 10.1136/bmjopen-2018-023673.
Chronic obstructive airway disease, which is characterised by airflow limitation, is a major burden on public health. Reductions in environmental pollution in the atmosphere and workplace and a decline in the prevalence of smoking over recent decades may have affected the prevalence of airflow limitation in Japan. The present epidemiological study aimed to evaluate trends in the prevalence of airflow limitation and in the influence of risk factors on airflow limitation in a Japanese community.
Two serial cross-sectional surveys.
Data from the Hisayama Study, a population-based prospective study that has been longitudinally conducted since 1961.
A total of 1842 and 3033 residents aged ≥40 years with proper spirometric measurements participated in the 1967 and 2012 surveys, respectively.
Airflow limitation was defined as forced expiratory volume in 1 s/forced vital capacity <70% by spirometry. For each survey, the age-adjusted prevalence of airflow limitation was evaluated by sex. ORs and population attributable fractions of risk factors on the presence of airflow limitation were compared between surveys.
The age-standardised prevalence of airflow limitation decreased from 1967 to 2012 in both sexes (from 26.3% to 16.1% in men and from 19.8% to 10.5% in women). Smoking was significantly associated with higher likelihood of airflow limitation in both surveys, although the magnitude of its influence was greater in 2012 than in 1967 (the multivariable-adjusted OR was 1.63 (95% CI 1.19 to 2.24) in 1967 and 2.26 (95% CI 1.72 to 2.99) in 2012; p=0.007 for heterogeneity). Accordingly, the population attributable fraction of smoking on airflow limitation was 33.5% in 2012, which was 1.5-fold higher than that in 1967 (21.1%).
The prevalence of airflow limitation was decreased over 45 years in Japan, but the influence of smoking on airflow limitation increased with time.
以气流受限为特征的慢性阻塞性气道疾病是公共卫生的主要负担。近几十年来，大气和工作场所环境污染的减少以及吸烟率的下降，可能影响了日本气流受限的流行率。本项流行病学研究旨在评估日本社区气流受限的流行趋势，以及危险因素对气流受限的影响。
两项连续的横断面研究。
该研究的数据来自 1961 年开始进行的一项以人群为基础的前瞻性研究，即平山研究。
共有 1842 名和 3033 名年龄≥40 岁且具有适当肺量计测量值的居民分别参加了 1967 年和 2012 年的调查。
气流受限通过肺量计定义为 1 秒用力呼气量/用力肺活量<70%。对于每个调查，通过性别评估气流受限的年龄调整患病率。比较两次调查之间危险因素对气流受限存在的比值比（OR）和人群归因分数（population attributable fraction，PAF）。
在两性中，气流受限的年龄标准化患病率从 1967 年到 2012 年均降低（男性从 26.3%降至 16.1%，女性从 19.8%降至 10.5%）。吸烟在两次调查中均与气流受限的可能性增加显著相关，尽管 2012 年的影响程度大于 1967 年（多变量调整后的 OR 为 1967 年的 1.63（95%CI 1.19 至 2.24）和 2012 年的 2.26（95%CI 1.72 至 2.99）；异质性 p=0.007）。因此，2012 年吸烟对气流受限的人群归因分数为 33.5%，比 1967 年高 1.5 倍（21.1%）。
日本气流受限的流行率在 45 年内下降，但吸烟对气流受限的影响随时间而增加。
