Emphysema-Predominant COPD Had a Greater 5-Year Mortality and a Worse Annual Decline in Lung Function Than Airway Obstruction-Predominant COPD or Asthma at Initial Same Degree of Airflow Obstruction

Medicina

Yu-Bin Pan¹  Lan-Yan Yang¹  Ting-Wen Wang²  Hung-Yu Huang³  Chun-Yu Lo³  Fu-Tsai Chung³  Yu-Chen Huang³  Chang-Wei Lin³  Chun-Hua Wang³  Kian Fan Chung⁴ 

[1] Biostatistics Unit, Clinical Trial Center, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan;Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, Taipei 100, Taiwan;Department of Thoracic Medicine, Chang Gung Memorial Hospital, Taipei 105, Taiwan;National Heart & Lung Institute, Imperial College London & Royal Brompton Hospital, London SW3 6LY, UK;

关键词: chronic obstructive pulmonary disease;    asthma;    emphysema;    6 min walk test;    pulmonary function;    desaturation;   

DOI  :  10.3390/medicina57111261

来源: DOAJ

【 摘 要 】

Background and Objectives: We studied whether the extent of exertional oxygen desaturation and emphysema could cause greater mortality in COPD and asthma independent of airflow obstruction. Materials and Methods: We performed a 5-year longitudinal observational study in COPD and asthma patients who matched for airflow obstruction severity. All subjects performed a 6-min walk test (6MWT) and high-resolution computed tomography (HRCT) and followed spirometry and oxygen saturation (SpO₂) during the 6MWT every 3–6 months. Overall survival was recorded. Cumulative survival curves were performed according to the Kaplan–Meier method and compared with the log-rank test. Results: The COPD group had higher emphysema scores, higher Δinspiratory capacities (ICs) and lower SpO₂ during the 6MWT, which showed a greater yearly decline in FEV₁ (40.6 mL) and forced vital capacity (FVC) (28 mL) than the asthma group (FEV₁, 9.6 mL; FVC, 1.2 mL; p < 0.05). The emphysema-predominant COPD group had an accelerated annual decline in lung function and worse survival. The nadir SpO₂ ≤ 80% and a higher emphysema score were the strong risk factors for mortality in COPD patients. Conclusions: The greater structural changes with a higher emphysema score and greater desaturation during the 6MWT in COPD may contribute to worse yearly decline in FEV₁ and higher five-year mortality than in asthma patients with a similar airflow obstruction. The lowest SpO₂ ≤ 80% during the 6MWT and emphysema-predominant COPD were the strong independent factors for mortality in chronic obstructive airway disease patients.

【 授权许可】

Unknown