Relationship between lung function impairment and incidence or recurrence of cardiovascular events in a middle-aged cohort

¹ University of Kentucky Medical Center, United States
² GlaxoSmithKline, United Kingdom
³ GlaxoSmithKline, United States

^* To whom correspondence should be addressed. E-mail: dmannino{at}uky.edu.

Accepted 23 December 2007

	Abstract

Introduction: Lung function impairment may be a risk factor for cardiovascular disease (CVD) events.

Objective: To determine the relationship between the severity of airflow obstruction based on modified Global Initiative on Obstructive Lung Disease (GOLD) criteria and the prevalence, and incidence or recurrence of CVD in a cohort of U.S. adults ages 45-64 years from 1987 through 2001.

Methods: We analyzed data from 14,681 adults using logistic regression to determine the cross-sectional association between lung function impairment and prevalent CVD at baseline and Cox regression to examine the prospective association of lung function impairment at baseline with CVD over 15 years of follow-up. Models were adjusted for age, sex, race, smoking, comorbid hypertension and diabetes, cholesterol levels, and fibrinogen level.

Results: At baseline, the crude prevalence of CVD was higher among subjects with GOLD 2 (odds ratio [OR] 2.9, 95% confidence interval [CI] 2.0, 4.5) and GOLD 3 or 4 COPD (OR 3.0, 95% CI 0.8, 2.1), compared to normal subjects. These relative risks were greatly reduced after adjusting for covariates (OR 1.4, 95% CI 1.2, 1.8 for GOLD 2 and OR 1.3, 95% CI 0.8, 2.1 for GOLD 3 or 4). Similarly, the association between COPD and risk of incident or recurrent CVD was much stronger in the unadjusted models (hazard ratio [HR] 2.4, 95% CI 2.4, 2.7 for GOLD 2 and 2.9, 95% CI 2.2, 3.9 for GOLD 3 or 4) than in the adjusted ones (HR 1.2, 95% CI 1.03, 1.4 for GOLD 2 and 1.5, 95% CI 1.1, 2.0 for GOLD 3 or 4).

Conclusion: We observed a crude association between lung function impairment and prevalent and incident or recurrent CVD that was greatly reduced after adjusting for covariates including age, sex, race, smoking, comorbid hypertension and diabetes, cholesterol levels, and fibrinogen level. These data suggest that this association may be, in part, mediated through established CVD risk factors included in our adjusted models.

Keywords: COPD, GOLD classification, cardiovascular disease, inflammation, restrictive lung disease