The Value of Forced Expiratory Volume in 1 Second Decline in the Assessment of Chronic Obstructive Pulmonary Disease Progression

Abstract 

Forced expiratory volume in 1 second (FEV₁) declines normally with aging by approximately 30 mL/yr, but in susceptible smokers, the decline is greater (about 60 mL/yr), resulting in the development of chronic obstructive pulmonary disease (COPD). Smoking cessation usually restores the normal or near-normal rate of FEV₁ decline, whereas intermittent quitting provides less benefit. Thus, smoking cessation is a critical component for the prevention of COPD progression. FEV₁ is central to the definition of COPD and classification of its severity. FEV₁ is a good predictor of exercise tolerance and correlates with survival and quality of life. More rapid FEV₁ decline is also predictive of morbidity, mortality, and hospitalization rates. Risk factors for accelerated decline in FEV₁, in addition to smoking, include frequent exacerbations, airways reactivity, and possibly chronic systemic inflammation. Genetic components of the decline in FEV₁ are being actively explored, but none has been extensively validated other than α₁-antitrypsin deficiency. To date, only smoking cessation has been definitively shown to be effective in reducing the rate of FEV₁ decline, but other therapeutic strategies are under active research. Consequently, FEV₁ and its change over time are important outcomes in COPD and valuable measures for the assessment of disease progression.

Keywords:  Chronic obstructive pulmonary disease (COPD) , COPD epidemiology , Quality of life , Spirometry