Background. COPD in never-smokers exposed to organic dusts is still poorly characterized. Therapeutic strategies in COPD are only evaluated in smoking-related COPD. To understand how never-smokers with COPD behave during exercise is an important prerequisite for optimal management. Objectives. To compare physiological parameters measured at exercise between never-smokers exposed to organic dusts with COPD and patients with smoking-related COPD matched for age, sex and severity of airway obstruction. Healthy controls were also studied. Methods. Dyspnea (Borg scale), exercise tolerance and ventilatory constraints were assessed during incremental cycle cardiopulmonary exercise testing in COPD patients at mild-to-moderate stages (22 exposed to organic dusts, postbronchodilator FEV₁/FVC z-score: -2.44±0.72 and FEV₁z-score: -1.45±0.78; 22 with smoking-related COPD, FEV₁/FVC z-score: -2.45±0.61; FEV₁z-score: -1.43±0.69) and 44 healthy controls (including 22 never-smokers). Results. Despite the occurrence of similar significant dynamic hyperinflation, never-smokers COPD patients exposed to organic dusts had lower dyspnea ratings than those with smoking-related COPD. They also had higher peak oxygen consumption, peak power output and better ventilatory efficiency than smoking-related COPD, all these parameters being similar controls. Differences in exercise capacity between the two groups of COPD were mainly driven by better ventilatory efficiency stemming from preserved diffusing capacity.Conclusion Never-smokers exposed to organic dusts with mild-to-moderate COPD have better exercise capacities, better ventilatory efficiency and better diffusion capacity than matched patients with smoking-related COPD.

中文翻译：

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与COPD相匹配的吸烟者相比，职业COPD的不吸烟者运动能力和通气效率更高

背景。接触有机粉尘的从不吸烟者的COPD仍较差。仅在与吸烟有关的COPD中评估COPD中的治疗策略。了解不吸烟的COPD者在运动过程中的行为是最佳管理的重要先决条件。目标。为了比较在运动中测得的从未吸烟者接触过COPD有机尘埃的吸烟者与年龄，性别和气道阻塞严重程度相匹配的吸烟相关COPD患者在运动中测得的生理参数。还研究了健康对照。方法。在COPD患者的轻度至中度阶段（22暴露于有机粉尘，支气管扩张剂后FEV ₁ / FVC z评分：-2.44±0.72和22）时，在增量循环心肺运动测试期间评估呼吸困难（Borg量表），运动耐受性和通气限制。电动汽车_1个z评分：-1.45±0.78；22与吸烟相关的COPD，FEV ₁ / FVC z评分：-2.45±0.61；FEV ₁z评分：-1.43±0.69）和44位健康对照（包括22位从不吸烟者）。结果。尽管发生了类似的显着动态过度恶性通气，但从未吸烟者接触有机粉尘的COPD患者的呼吸困难等级低于吸烟相关的COPD患者。与吸烟相关的COPD相比，它们的峰值耗氧量，峰值功率输出和更好的通风效率，所有这些参数都是相似的对照。两组COPD的运动能力差异主要是由扩散能力得以保持而导致的通气效率提高所致。结论从未接触过具有中度至中度COPD有机粉尘的不吸烟者具有更好的运动能力，更好的通气效率和更好的扩散能力比与吸烟相关的COPD患者匹配。