Liu Sha, Zhou Yumin, Zou Weifeng, Tan Xiaowu, Ran Pixin
The Second Hospital, University of South China, Hengyang, China.
The State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Diseases, Guangzhou Institute of Respiratory Health, the First Affiliated Hospital, Guangzhou Medical University. Guangzhou, China.
J Thorac Dis. 2021 Jul;13(7):4043-4053. doi: 10.21037/jtd-21-95.
To reappraise the prevalence and characteristics of chronic obstructive pulmonary disease (COPD) in China with a criterion of FEV/FVC < the lower limit of normal (LLN).
We assessed the incidence and characteristics of airflow limitation using data from the Chinese Epidemiological Survey of COPD study-a multicenter, randomized trial, with an age-dependent LLN reference equation [established by the Guangzhou Institute of Respiratory Health (GIRH)]. Questionnaire and spirometry data were collected for all eligible subjects. COPD prevalence, risk factors, severity distribution, as well as comparisons of characteristics between the LLN and 0.7 were analyzed.
COPD prevalence was 9.0% among participants aged 40-80 years in China with the criterion of LLN. Greater prevalence was observed in female sex, rural areas and never smokers than with the GOLD 0.7 fixed ratio. Age distribution showed a higher incidence of COPD in people under 60 years but lower in participants over 60 years of age. With the LLN FEV reference equation, patients in stage I were decreased (15.8% 24.6%, P<0.001), while the proportion of patients in stage III and IV were increased when compared with the China 2002 revised equation (27.7% 21.1%, for stage III, P<0.001; 8.7% 5.6% for stage IV, P=0.001). Only 30.8% of patients with COPD had ever been "diagnosed" with COPD and 60.6% of the patients had respiratory symptoms, both lower than that under the GOLD 0.7 fixed-ratio criterion (35.5%, P=0.004; 64.8% for symptoms, P=0.014).
With the GIRH-LLN criterion, COPD prevalence was slightly higher, and a large number of women, rural patients and nonsmokers with young age and little symptoms were diagnosed when compared with GOLD 0.7 fixed ratio. These subjects may, therefore, deserve further attention and may warrant regular follow-up.
Registration number: ChiCTR-ECS-13004110.
采用FEV/FVC <正常下限（LLN）的标准重新评估中国慢性阻塞性肺疾病（COPD）的患病率及特征。
我们利用中国慢性阻塞性肺疾病流行病学调查研究的数据评估气流受限的发生率及特征，该研究为一项多中心随机试验，采用了基于年龄的LLN参考方程[由广州医科大学附属第一医院（广州呼吸健康研究院）建立]。收集了所有符合条件受试者的问卷和肺功能数据。分析了COPD患病率、危险因素、严重程度分布，以及LLN标准与0.7标准之间特征的比较。
以LLN为标准，中国40 - 80岁参与者中COPD患病率为9.0%。与全球慢性阻塞性肺疾病倡议（GOLD）0.7固定比值标准相比，女性、农村地区及从不吸烟者中的患病率更高。年龄分布显示，60岁以下人群中COPD发病率较高，而60岁以上参与者中发病率较低。采用LLN的FEV参考方程时，与中国2002年修订方程相比，I期患者比例降低（15.8%对24.6%，P<0.001），而III期和IV期患者比例增加（III期为27.7%对21.1%，P<0.001；IV期为8.7%对5.6%，P = 0.001）。只有30.8%的COPD患者曾被“诊断”为COPD，60.6%的患者有呼吸道症状，两者均低于GOLD 0.7固定比值标准下的比例（诊断比例为35.5%，P = 0.004；症状比例为64.8%，P = 0.014）。
采用广州呼吸健康研究院的LLN标准时，COPD患病率略高，与GOLD 0.7固定比值标准相比，有大量年龄较轻、症状较少的女性、农村患者及不吸烟者被诊断出来。因此，这些受试者可能值得进一步关注，或许需要定期随访。
注册号：ChiCTR-ECS-13004110。
