Table 1.

Demographics.

	Group
	Control (n = 8)	COPD (n = 28)
Age*, median (interquartile range), years	54 (9)	61 (10)
Gender†, female (number)	2	9
Pack-year smoking history, median (interquartile range)	0	47 (23)
FEV1/FVC%¶, median (interquartile range)	79 (17)	57 (16)

* P = 0.1 (Mann-Whitney test).

^† P = 0.2 (Fisher's Exact test).

^¶ P < 0.001.