NATURAL HISTORY OF CHRONIC AIRFLOW OBSTRUCTION

The proposed work is a continuation of longitudinal studies of three populations
in order to (1) determine the predictive value of the single breath N2 test in
identifying the individual who is going to progress to chronic airflow
obstruction; (2) determine the contribution of various host and environmental
factors to the development of chronic airflow obstruction; and (3) obtain
further information about how lungs age and what factors affect aging. The population groups are (1) smokers and nonsmokers who were first tested at an
emphysema screening center in 1971/72 and subsequently tested in 1975 and 1977;
(2) a random sample of a working population studied in 1974, 1976, and 1978; and
(3) parents of 19 children with homozygous alpha1-antitrypsin deficiency studied
annually from 1976 to 1978.
Our data base will include (1) information, obtained by questionnaire, relating
to respiratory symptoms, smoking habits, chest illnesses, occupation, residence
and family history of chest problems; (2) pulmonary function tests; spirometric
tests before and after a bronchodilator and the single breath N2 test - a test
of small airway function; and (3) trypsin inhibitory capacity and phenotyping
for alpha1-antitrypsin deficiency. Subjects will be tested either annually or
biennially giving a total follow-up time varying between 8 and 12 years.