Background

Reference equations from the Global Lung Function Initiative (GLI) are now available for both spirometry and diffusion. However, respiratory phenotypes defined by GLI-based measures of diffusion have not yet been evaluated in GLI-based normal-for-age spirometry or spirometric impairments.

Methods

We evaluated cross-sectional data from 2100 Caucasians, aged 40–85 years. GLI-based spirometric categories included normal-for-age and the impairments of restrictive-pattern and three-level severity of airflow-obstruction (mild, moderate, severe). GLI-based diffusion included diffusing capacity of the lung for carbon monoxide (D_LCO) and measured components of alveolar volume (V_A) and transfer coefficient (K_CO): D_LCO = [V_A]x[K_CO]. Using multivariable regression models, adjusted odds ratios (adjORs) for D_LCO, V_A, and K_CO < lower limit of normal (LLN) were calculated for spirometric impairments, relative to normal-for-age spirometry.

Results

Relative to normal-for-age spirometry, the restrictive-pattern increased the adjORs (95% confidence intervals) for D_LCO and V_A < LLN—4.61 (3.62, 5.85) and 15.53 (11.8, 20.4), respectively, but not for K_CO < LLN—1.02 (0.79, 1.33). Also relative to normal-for-age spirometry, airflow-obstruction from mild to severe increased the adjORs for D_LCO < LLN—from 1.22 (0.80, 1.86) to 6.63 (4.91, 8.95), for V_A < LLN—from 1.37 (0.85, 2.18) to 7.01 (5.20, 9.43), and for K_CO < LLN—from 2.04 (1.33, 3.14) to 3.03 (2.29, 3.99). Notably, in normal-for-age spirometry, 34.5%, 19.7%, and 25.3% of participants had D_LCO, V_A, or K_CO < LLN, respectively.

Conclusion

Abnormal diffusion is most prevalent in spirometric impairments but also occurs in normal-for-age spirometry. These results further inform the respiratory phenotypes of GLI-based spirometric categories and, in turn, the spirometric evaluation of respiratory disease.

中文翻译：

---

使用来自全球肺功能倡议的参考方程，在正常年龄肺活量测定法和肺活量测定损伤中的扩散能力。

背景

来自全球肺功能倡议 (GLI) 的参考方程现在可用于肺活量测定和扩散。然而，尚未在基于 GLI 的正常年龄肺活量测定法或肺活量测定损伤中评估由基于 GLI 的扩散测量定义的呼吸表型。

方法

我们评估了 2100 名年龄在 40-85 岁之间的白种人的横断面数据。基于 GLI 的肺活量类别包括正常年龄和限制型障碍以及气流阻塞的三级严重程度（轻度、中度、重度）。基于 GLI 的扩散包括肺对一氧化碳的扩散能力 (D _LCO ) 和测量的肺泡体积 (V _A ) 和转移系数 (K _CO ) 的组成部分：D _LCO  = [V _A ]x[K _CO ]。使用多变量回归模型，调整比值比（adjORs）为d _LCO，V_甲和K _CO < 正常下限 (LLN) 是针对肺功能障碍计算的，相对于正常年龄肺量测定。

结果

相对于正常年龄肺活量测定，限制模式增加了 D _LCO和 V _A  < LLN的 adjORs（95% 置信区间）—分别为4.61 (3.62, 5.85) 和 15.53 (11.8, 20.4)，但对于K _CO  < LLN—1.02 (0.79, 1.33)。同样相对于正常年龄肺活量测定法，从轻度到重度的气流阻塞使 D _LCO  < LLN的 adjOR从 1.22 (0.80, 1.86) 增加到 6.63 (4.91, 8.95)，对于 V _A  < LLN，从 1.37 ( 0.85, 2.18) 到 7.01 (5.20, 9.43)，对于 K _CO  < LLN - 从 2.04 (1.33, 3.14) 到 3.03 (2.29, 3.99)。值得注意的是，在正常换年龄肺活量测定，34.5％，19.7％，和参与者的25.3％有d _LCO，V_甲，或K _CO < LLN，分别。

结论

异常扩散在肺功能障碍中最为普遍，但也发生在正常年龄的肺量测定中。这些结果进一步为基于 GLI 的肺活量类别的呼吸表型提供信息，进而为呼吸系统疾病的肺量测定评估提供信息。