Interviews Each participant was administered a structured questionnaire to assess lifetime residential and occupational history (all jobs or residences occupied
≥6 months), water source types (municipal tap water, bottled, other), current medications, and medical history. Smoking histories included ages started and quit, years smoked, and average cigarettes smoked per day. Ever smoking regularly was Selleckchem Volasertib defined as smoking cigarettes at least once per week for ≥1 year, or 20 packs lifetime. Secondhand smoke was defined as someone smoking regularly in the same room at home or at work. Indoor air pollution selleck inhibitor was defined as irritating or visible smoke, vapors, gases, or dust regularly in the same room. Subjects were also asked about the types of fuels used at home. Occupational exposure was defined as ever being exposed regularly to vapors, dust, gas, or fumes at a job held for ≥6 months (Blanc et al. 2005). Standardized questions were adapted to local Spanish from questionnaires used by the Latin American Project for the Investigation of Obstructive
Lung Diseases (PLATINO), the third U.S. National Health and Nutrition Examination Survey (NHANES III), and the second European Community Respiratory Health Survey (ECRHS II). Questions about respiratory symptoms were adapted from the British Medical Research Council (Cotes 1987). Participants were asked, “Do you often cough when you don’t have a cold, such as in the mornings in winter?” Chronic cough was assessed with the follow-up question, “Do you cough like this for at least 3 months a year?” The same questions
were asked for phlegm. Subjects were also asked check details whether they had trouble breathing (1) rarely, (2) often, or (3) always. Finally, participants were asked whether they became breathless GBA3 when (1) hurrying on level ground or walking up a slight hill, (2) walking with other people of the same age on level ground, or (3) if they had to stop for breath when walking on level ground at one’s own pace. Lung function measurement using spirometry After height and weight were measured by nurse-interviewers, lung function was assessed according to American Thoracic Society guidelines (ATS 1995) using an EasyOne spirometer (NDD Medical Technologies, Zurich, Switzerland) in diagnostic mode. The same trained technician used the same spirometer in Antofagasta and Arica. Subjects were instructed to take as deep a breath as possible and then blow as hard and long as possible into the spirometer. Following a demonstration and practice with the mouthpiece, they performed tests in a sitting position with active coaching. The main lung function values assessed were forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC). The maneuver was repeated until the EasyOne indicated satisfactory results were achieved (e.g., FEV1 and FVC within 200 ml of previous values) or the participant chose to stop. Each subject’s best trial (largest sum of FEV1 and FVC) was included in analyses.