Robbins D R, Enright P L, Sherrill D L
Respiratory Sciences Center, University of Arizona, College of Medicine, Tucson 85724, USA.
Eur Respir J. 1995 May;8(5):768-72.
Numerous population studies have reported that pulmonary function following the adolescent growth phase appears to be in a steady-state, where there is little or no growth occurring up to 40 yrs of age. We examined longitudinal forced expiratory volume in one second (FEV1), changes using three different statistical approaches to determine which subjects actually have significant trends during this period. Participants, who were employees at a metal processing plant, underwent quarterly spirometry for up to 10 yrs. Test results up to 33 yrs of age were included in the analysis. Each subject's FEV1 data was first analysed using simple linear regression (SLR) to test for a statistically significant linear slope. Next, each subject's data were fitted using bootstrap sampling (BSS) of their original data, to yield reduced estimates of the slope variances and increase the power of detecting a significant trend. And thirdly, we fitted a regression breakpoint (BKPT) model to the data to find those subjects who may have piecewise linear growth or decline in function. All analyses were stratified, based on smoking status. Subjects included 111 nonsmokers and 110 smokers. Among the nonsmokers, 34 subjects had significant slopes using SLR, an additional three using BSS, and only two with BKPT. Among the smokers, 36 had a significant trend using SLR, 7 were added using BSS, and no additional subjects with BKPT. We conclude that in young adult males lung function is not in a steady-state and that as many as 40% have a significant slope, either positive or negative.(ABSTRACT TRUNCATED AT 250 WORDS)
众多人群研究报告称，青春期生长阶段后的肺功能似乎处于稳定状态，在40岁之前几乎没有增长或没有增长。我们检查了纵向一秒用力呼气量（FEV1），使用三种不同的统计方法进行分析，以确定在此期间哪些受试者实际上有显著趋势。参与者是一家金属加工厂的员工，接受了长达10年的季度肺活量测定。分析纳入了33岁之前的测试结果。首先使用简单线性回归（SLR）分析每个受试者的FEV1数据，以检验是否存在具有统计学意义的线性斜率。接下来，使用原始数据的自助抽样（BSS）对每个受试者的数据进行拟合，以得出斜率方差的降低估计值，并提高检测显著趋势的能力。第三，我们对数据拟合回归断点（BKPT）模型，以找出那些肺功能可能有分段线性增长或下降的受试者。所有分析均根据吸烟状况进行分层。受试者包括111名不吸烟者和110名吸烟者。在不吸烟者中，34名受试者使用SLR时有显著斜率，另外3名使用BSS时出现显著斜率，只有2名使用BKPT时出现显著斜率。在吸烟者中，36名使用SLR时有显著趋势，7名使用BSS时新增显著趋势，使用BKPT时无新增受试者。我们得出结论，年轻成年男性的肺功能并非处于稳定状态，多达40%的人有显著斜率，无论是正向还是负向。（摘要截断于250字）
