1 Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
2 Pulmonary and Critical Care Section, VA Boston Healthcare System, Boston, Massachusetts.
Am J Respir Crit Care Med. 2018 Dec 1;198(11):1397-1405. doi: 10.1164/rccm.201804-0663OC.
Increasing awareness of the prevalence and significance of Preserved Ratio Impaired Spirometry (PRISm), alternatively known as restrictive or Global Initiative for Chronic Obstructive Lung Disease (GOLD)-unclassified spirometry, has expanded the body of knowledge on cross-sectional risk factors. However, longitudinal studies of PRISm remain limited.
To examine longitudinal patterns of change in lung function, radiographic characteristics, and mortality of current and former smokers with PRISm.
Current and former smokers, aged 45 to 80 years, were enrolled in COPDGene (phase 1, 2008-2011) and returned for a 5-year follow-up (phase 2, 2012-2016). Subjects completed questionnaires, spirometry, chest computed tomography scans, and 6-minute-walk tests at both study visits. Baseline characteristics, longitudinal change in lung function, and mortality were assessed by post-bronchodilator lung function categories: PRISm (FEV/FVC < 0.7 and FEV < 80%), GOLD0 (FEV/FVC > 0.7 and FEV > 80%), and GOLD1-4 (FEV/FVC < 0.7).
Although the prevalence of PRISm was consistent (12.4-12.5%) at phases 1 and 2, subjects with PRISm exhibited substantial rates of transition to and from other lung function categories. Among subjects with PRISm at phase 1, 22.2% transitioned to GOLD0 and 25.1% progressed to GOLD1-4 at phase 2. Subjects with PRISm at both phase 1 and phase 2 had reduced rates of FEV decline (-27.3 ± 42.1 vs. -33.0 ± 41.7 ml/yr) and comparable proportions of normal computed tomography scans (51% vs. 52.7%) relative to subjects with stable GOLD0 spirometry. In contrast, incident PRISm exhibited accelerated rates of lung function decline. Subjects with PRISm at phase 1 had higher mortality rates relative to GOLD0 and lower rates relative to the GOLD1-4 group.
PRISm is highly prevalent, is associated with increased mortality, and represents a transitional state for significant subgroups of subjects. Additional studies to characterize longitudinal progression in PRISm are warranted.
对肺功能储备受损（PRISm），亦称限制性或全球慢性阻塞性肺疾病倡议（GOLD）未分类的肺功能的流行程度和意义的认识不断提高，这扩大了对横断面危险因素的了解。然而，关于 PRISm 的纵向研究仍然有限。
研究当前和以前吸烟者中 PRISm 的肺功能、影像学特征和死亡率的纵向变化模式。
年龄在 45 至 80 岁的当前和以前吸烟者参加了 COPDGene（第 1 阶段，2008-2011 年）并返回进行 5 年随访（第 2 阶段，2012-2016 年）。在两次研究访视时，受试者完成了问卷调查、肺功能检查、胸部计算机断层扫描和 6 分钟步行测试。通过支气管扩张剂后肺功能分类评估基线特征、肺功能的纵向变化和死亡率：PRISm（FEV/FVC<0.7 和 FEV<80%）、GOLD0（FEV/FVC>0.7 和 FEV>80%）和 GOLD1-4（FEV/FVC<0.7）。
尽管第 1 阶段和第 2 阶段 PRISm 的患病率保持一致（12.4-12.5%），但 PRISm 患者向其他肺功能分类的转变率很高。在第 1 阶段有 PRISm 的患者中，22.2%转为 GOLD0，25.1%在第 2 阶段进展为 GOLD1-4。在第 1 阶段和第 2 阶段均有 PRISm 的患者的 FEV 下降速度较慢（-27.3±42.1 与-33.0±41.7 ml/yr），且正常计算机断层扫描的比例相当（51%与 52.7%），与稳定的 GOLD0 肺功能相比。相比之下，新发 PRISm 患者的肺功能下降速度更快。与 GOLD0 相比，第 1 阶段有 PRISm 的患者的死亡率较高，而与 GOLD1-4 组相比，死亡率较低。
PRISm 患病率高，与死亡率增加相关，是许多患者的重要过渡状态。需要进一步的研究来描述 PRISm 的纵向进展。
