National Health and Nutrition Examination Survey (Nhanes)

Spirometry, which means "the measuring of breath," is a routinely used pulmonary function test (PFT) that measures the amount and speed of air that a person can inhale and exhale. Results from the test can be used to estimate lung function and aid in the diagnosis of certain respiratory disorders. The current NHANES spirometry component is sponsored by the Centers for Disease Control and Prevention, National Institute for Health Statistics (CDC/NCHS), the National Heart, Lung, and Blood Institute (NHLBI), and the National Institute for Occupational Safety and Health (NIOSH). The objective of the 2007-8 spirometry data collection cycle is to assess the prevalence of asthma and adult chronic obstructive pulmonary disease (COPD) in the U.S. population. The data will also be used to produce updated spirometric reference data for the general population. Moreover, comparisons of 2007-8 data with that of previous studies will illuminate trends in asthma and COPD prevalence over time in the United States. Spirometry is part of the Respiratory Health (RH) component, together with Exhaled Nitric Oxide (ENO) testing (please refer to the ENO Procedures Manual for further details). The spirometry component will include a subcomponent in which the spirometry exam will be repeated on a small subset of participants following the administration of a bronchodilator medication. This will make it possible to distinguish between COPD and asthma, which have similar baseline spirometry profiles but differ in post-bronchodilator spirometry testing. This distinction is important because, although asthma and COPD have similar symptoms, they are associated with different risk factors and molecular and patho-physiologic mechanisms. The bronchodilator evaluation will be conducted by the MEC physician (see Bronchodilator Component Procedures Manual for details).