This report focuses on the GOLD 0 group(n=4388), defined as current and former smokers with a normal postbron-chodilator ratio of FEV1 to forced vital capacity exceeding 0.7 and an FEV1 percentage of at least 80% predicted. They were compared with never smokers(n=108) and with the GOLD1 (mildCOPD) group(n=794).