Background: Individuals with impaired lung function have an elevated risk of cardiovascular events. Improved understanding of the factors associated with increased cardiovascular risk in the setting of lung function impairment is needed. We set out to determine in a nationwide population-based cohort whether impaired lung function as measured by forced expiratory volume in 1 s (FEV1) is associated with evidence of increased arterial stiffness measured by peripheral pulse pressure, a risk factor for cardiovascular events.
Methods: Cross-sectional study of adults > or = 20 years of age in the Third National Health and Nutrition Examination Survey (NHANES III) who had valid and reproducible FEV1 data and serial blood pressure measurements allowing for the calculation of a mean pulse pressure, a measure of central arterial stiffness (n = 13,090).
Results: There was a significant negative correlation between FEV1 and mean pulse pressure (r = -0.37). After controlling for demographic variables and confounders including cardiovascular risk factors, smoking history, and lung disease, the negative relationship between pulse pressure and FEV1 varies with age and becomes apparent only after age 40. In individuals aged 40-59 and > or = 60 years, there was respectively a 2 and 3 mm Hg increment in pulse pressure for every one standard deviation decrement in FEV1.
Conclusions: FEV1 is significantly related to pulse pressure, a clinically important measure of arterial stiffness, among those aged > or = 40 years. This relationship may help to explain the increased risk of cardiovascular events found in individuals with impaired lung function.