. Author manuscript; available in PMC: 2011 May 1.

Published in final edited form as: Am J Med. 2010 May;123(5):468.e1–468.e7. doi: 10.1016/j.amjmed.2009.07.037

Table 1. Participant Characteristics at Years 0 and 20.

	Year 0	Year 20
Number	2,496
Age – years	25.1 (3.6)	45.3 (3.6)
Male (%)	45.4
White (vs. black) (%)	56.9
Education > high school (%)	67.2	77.4
BMI – kg/m²	24.4 (4.7)	29.1 (6.6)
Smoking – current / previous / never (%)	25.0/14.4/60.6	18.0/19.5/62.4
Exposure to second hand smoke (%)	95.5	47.8
FEV₁ % predicted	98.9 (11.2)	95.2 (13.8)
FVC % predicted	100.7 (11.3)	96.6 (13.4)
FEV₁/FVC	0.84 (0.06)	0.79 (0.06)
FEV₁/FVC < LLN (%)	6.9	7.8
Self reported doctor or nurse diagnosis of COPD (%)	54 (2.2%)	50 (2.0%)^*
- Chronic bronchitis	48	45
- Emphysema	6	6
- COPD	N.A.	3

The results are mean (SD) unless otherwise noted.

The total number of COPD diagnoses (chronic bronchitis, emphysema, COPD) adds up to more than 50 since some participants reported more than one diagnosis.

N.A. – Not applicable as COPD was not a choice in the Year 0 questionnaires.