Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2012 Dec;142(6):1530-1538.
doi: 10.1378/chest.11-2837.

Lung function decline in male heavy smokers relates to baseline airflow obstruction severity

Affiliations

Lung function decline in male heavy smokers relates to baseline airflow obstruction severity

Firdaus A A Mohamed Hoesein et al. Chest. 2012 Dec.

Abstract

Background: Recent evidence indicates that the rate of lung function decline is steepest in mild COPD and slower in moderate to severe COPD. The current study assessed whether lung function decline relates to baseline airflow obstruction severity in male heavy smokers.

Methods: In total, 2,003 male smokers with a mean (SD) age of 59.8 (5.3) years underwent pulmonary function testing at baseline and after 3-year follow-up. Participants were classified by entry FEV1/FVC as follows: group 1, >70%; group 2, <70%, but greater than lower limit of normal (LLN); and group 3, less than LLN. Differences in lung function decline among the groups were assessed using multiple regression after adjustment for pack-years, smoking status (current or former smoker), presence or absence of mucus production, medical center, height, age, CT scan-derived emphysema severity (15th percentile), observation time (years in study), and the baseline values.

Results: Over 3 years, the mean (SD) FEV₁/FVC, FEV₁, and maximum expiratory flow at 50% of FVC decreases in group 1 were 3.1% (1), 0.21 L (0.07), and 0.40 L/s (0.26), respectively. In group 3, these decreases were 2.4% (1.1), 0.15 L (0.08), and 0.06 L/s (0.19), respectively. All lung function parameters showed the greatest decline in group 1 (P < .001).

Conclusions: Diagnosing COPD based on the presence of more severe airflow obstruction (as defined by FEV₁/FVC less than LLN) means that, at the time of such a diagnosis, subjects had passed the phase of strong lung-function decline.

Trial registry: ISRCTN Register; No.: ISRCTN63545820; URL: www.trialregister.nl

PubMed Disclaimer

Comment in

Similar articles

Cited by

Publication types

Associated data

LinkOut - more resources