Department of Respiratory Medicine, Qilu Hospital, Shandong University, Jinan, Shandong 250012, China.
Chin Med J (Engl). 2013;126(18):3486-92.
It remains controversial what better defines abnormal lung function at the extremes of age. This study aimed to establish new spirometric reference equations for residents in Jinan and compare the most accepted two spirometric definitions of chronic obstructive pulmonary disease (COPD)-a fixed post-bronchodilator ratio of forced expiratory volume in one second to forced vital capacity (FEV1/FVC) below 70% vs. FEV1/FVC < lower limit of normal (LLN)-in an elderly population (age ≥60 years).
Among 10 002 cases, only never-smokers who had no respiratory symptoms or diagnoses of cardiopulmonary diseases and whose lung function measurements strictly followed the American Thoracic Society guidelines, were included in the statistical analysis. For each gender, prediction equations of FEV1, FVC, FEV1/FVC and corresponding LLN values were developed using multiple regression models.
In this cross-sectional study, spirometric reference values were statistically derived from a sample of 1328 healthy never-smokers (672 males, 656 females), age 56-84 years. As expected, age and height were the main predictors for all lung function parameters. Using the two spirometric definitions, the number of pulmonary function test results interpreted as obstructed varied markedly in the elderly population for both genders (males: χ(2) = 19.59, P < 0.01; females: χ(2) = 5.67, P = 0.017).
The Global Initiative for Chronic Obstructive Lung Disease (GOLD) criterion probably leads to overdiagnosis in asymptomatic elderly never-smokers. Our study suggests that the predicted LLN values will reduce the misclassification risk instead. However, cohort studies are urgently needed for clinical validation.
在年龄极值处，何种指标更能定义异常肺功能仍存在争议。本研究旨在建立济南地区居民的新肺功能参考方程，并比较两种最被认可的慢性阻塞性肺疾病（COPD）的肺功能定义，即使用支气管扩张剂后一秒用力呼气容积（FEV1）与用力肺活量（FVC）的比值（FEV1/FVC）＜70%，或 FEV1/FVC＜正常下限值（LLN），用于老年人群（年龄≥60 岁）。
在 10002 例患者中，仅纳入无呼吸系统症状或心肺疾病诊断且肺功能检测严格遵循美国胸科学会指南的从不吸烟者进行统计分析。对于每个性别，使用多元回归模型建立 FEV1、FVC、FEV1/FVC 及相应 LLN 值的预测方程。
在这项横断面研究中，通过对 1328 例健康从不吸烟者（672 名男性，656 名女性）的样本进行统计分析，得出了肺功能参考值，年龄为 56-84 岁。正如预期的那样，年龄和身高是所有肺功能参数的主要预测因素。使用两种肺功能定义，对于男性（χ²=19.59，P＜0.01）和女性（χ²=5.67，P=0.017），两种定义下的肺功能检测结果被判断为阻塞性的数量在老年人群中差异显著。
全球慢性阻塞性肺疾病倡议（GOLD）标准可能导致无症状的老年从不吸烟者过度诊断。我们的研究表明，预测的 LLN 值将降低误诊风险。然而，迫切需要进行临床验证的队列研究。
