Table 1

Demographics of baseline (Array) and year one (PCR) cohorts

	Baseline cohort		Year one cohort
	Stage II	Stage III and IV	Stage II	Stage III and IV
N	74	74	94	82
Age	65	64	63	64
Males (%)	65	68	64	79
Pack years	48	49	51	56
FEV1 (L)	1.6	0.94	1.6	0.94
FEV1% Predicted	57	34	57	34
FEV1/FVC ratio	51	36	52	38
Exacerbation rates/year	1.06	2.00	0.90	2.01
% White	100	99	99	98
% Other race	0	1	1	2
% Low LAA	75	26	66	34
% High LAA	27	73	30	70
% Reversibility	11	8	12	13
% Inhaled Steroid use	79	87	83	91
% LABA use	74	92	83	89
% Tiotropium use	43	49	30	27
Total cell count (x 10⁶)	4.10	3.46	3.40	3.17
Sputum neutrophil (%)	79	87	80	82
Sputum macrophage (%)	18	9	17	14
Sputum eosinophil (%)	1	1	1	2
Sputum lymphocyte (%)	1	1	1	1

Exacerbation rates were calculated over the three years of the study. Values are means.
LABA, long acting beta agonist.