Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6 Pt 1
pubmed:dateCreated
1996-8-8
pubmed:abstractText
As part of a clinical trial of early intervention in chronic obstructive pulmonary disease (COPD) (the Lung Health Study), 5,733 smokers with mild to moderate airflow obstruction underwent methacholine challenge tests at baseline. All participants were randomized to receive either usual care (no intervention) or special intervention, consisting of intensive smoking cessation counseling and the prescription of a metered-dose inhaler containing either ipratropium bromide or placebo (two inhalations three times daily). For this report, we analyzed the relationship between baseline methacholine reactivity and subsequent change in lung function. Methacholine reactivity was expressed as a logarithmic function of the two-point slope of percent decline in FEV1 over the concentration of methacholine (LMCR). Using a random effects linear model, LMCR was found to be a strong predictor of change in FEV1% predicted, after controlling for baseline lung function, age, sex, baseline smoking history, and changes in smoking status. Significant interactions were found between reactivity and smoking behavior. In the first year, participants who quit smoking showed improvement in FEV1, whereas continuing smokers showed worsening, and between Years 1 and 5, lung function declined to a greater extent in continuing smokers than in sustained quitters. For both time periods, these quitter/smoker differences increased as a function of airway reactivity. These findings indicate that methacholine reactivity is an important predictor of progression of airway obstruction in continuing smokers with early COPD, independent of the baseline level of obstruct.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1073-449X
pubmed:author
pubmed:issnType
Print
pubmed:volume
153
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1802-11
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Methacholine reactivity predicts changes in lung function over time in smokers with early chronic obstructive pulmonary disease. The Lung Health Study Research Group.
pubmed:affiliation
UCLA School of Medicine, University of California at Los Angeles, Los Angeles, California 90095-1690, USA.
pubmed:publicationType
Journal Article, Clinical Trial, Research Support, U.S. Gov't, P.H.S., Randomized Controlled Trial, Multicenter Study