BACKGROUND The clinical and prognostic characteristics of mild-to-moderate chronic obstructive pulmonary disease (COPD) with and without emphysema remain inadequately investigated. RESEARCH QUESTION Do the clinical and prognostic characteristics differ between mild- to-moderate COPD with and without emphysema? STUDY DESIGN AND METHODS We obtained clinical data of 989 participants with mild-to-moderate COPD from the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS). They were categorized into two groups based on their baseline %LAA-950 of less than 5% on CT scans: those with emphysema (EC group) and those without emphysema (NEC group). Linear mixed-effects models were utilized to assess the differences in the decline of lung function, health-related quality of life, and quantitative CT indices between these two groups. Zero-inflated negative binomial regressions were employed to evaluate the rates of acute respiratory exacerbations between the groups. RESULTS Among participants with mild-to-moderate COPD, 428 (43.3%) exhibited emphysema on CT scans. The annual decline in FEV1 was -56.1 mL/year for the EC group and -46.9 mL/year for the NEC group, with a non-significant between-group difference of 9.1 mL/year (95% CI, -24.0 to 5.7 mL/year). The rate of emphysema progression in the EC group was significantly lower than in the NEC group (-0.173%; 95% CI, -0.252 to -0.094). The EC group also showed a more pronounced annual increase in the SGRQ score (0.9 points) compared to the NEC group. The EC group had a higher rate of acute respiratory exacerbations (0.36 per person-year) than the NEC group (0.25 per person-year), with a rate ratio of 1.42 (95% CI, 1.27 to 1.54). INTERPRETATION Mild-to-moderate COPD with emphysema did not have accelerated rates of decline in FEV1, but they experienced significantly worsen health-related quality of life and a higher rate of acute respiratory exacerbations. The non-emphysema subtype demonstrated increased emphysema progression.

中文翻译：

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轻度至中度 COPD 伴和不伴肺气肿的临床和预后差异。


背景 伴有和不伴有肺气肿的轻至中度慢性阻塞性肺疾病 （COPD） 的临床和预后特征仍未得到充分研究。研究问题 伴有肺气肿的轻至中度 COPD 的临床和预后特征是否不同？研究设计和方法 我们从 COPD 研究中的亚群和中间结果测量 （SPIROMICS） 中获得了 989 名轻度至中度 COPD 参与者的临床数据。根据 CT 扫描中基线 %LAA-950 小于 5%，将他们分为两组：肺气肿患者 （EC 组） 和无肺气肿患者 （NEC 组）。采用线性混合效应模型评估两组之间肺功能下降、健康相关生活质量和定量 CT 指数的差异。采用零膨胀负二项式回归来评估组间急性呼吸恶化的发生率。结果 在轻中度 COPD 参与者中，428 例 （43.3%） 在 CT 扫描中表现出肺气肿。EC 组 FEV1 的年下降为 -56.1 mL/年，NEC 组为 -46.9 mL/年，组间差异为 9.1 mL/年（95% CI，-24.0 至 5.7 mL/年）。EC 组肺气肿进展率显著低于 NEC 组 （-0.173%;95% CI，-0.252 至 -0.094）。与 NEC 组相比，EC 组的 SGRQ 评分年增长率 （0.9 分） 也更明显。EC 组急性呼吸恶化的发生率 （0.36/人年） 高于 NEC 组 （0.25/人年），比率为 1.42 （95% CI，1.27 至 1.54）。 解释 轻度至中度 COPD 伴肺气肿的 FEV1 下降速度没有加快，但与健康相关的生活质量显著恶化，急性呼吸恶化的发生率更高。非肺气肿亚型显示肺气肿进展加快。