Table 1. Clinical and demographic IPF variables categorized by FVC.

Variable	Characteristics	Mild IPF (N = 27)	Severe IPF (N = 13)	Controls (N = 27)
% Predicted FVC		85.0±8.1	42.5±6.6	NR
Age	Mean±SD	69.8±8.4	65.3±12.7	60.1±14.1
Sex	Male/Female	19/8	10/3	11/17
Smoking Status	Current	0	0	0
	Former	7	7	14
	Never	18	6	13
	Not Reported	2	0	0

Abbreviations: Idiopathic Pulmonary Fibrosis (IPF); Not Reported (NR); Diffusing Capacity for Carbon Monoxide (D_LCO); Forced Vital Capacity (FVC).