Table 1– Baseline cross-sectional characteristics and longitudinal changes in patients defined by peripheral blood eosinophil counts during follow-up

	Persistently ≥2%	Intermittent	Persistently <2%	ANOVA p-value
Subjects n	554	728	201
Age years	64±7	62±7	62±7	0.025
Male sex	68	64	56	0.007
Smoking history pack-years	47±26	47±26	48±30	0.810
Current smokers	30	36	42	0.004
Post-bronchodilator FEV₁ L	1.45±0.51	1.37±0.52	1.33±0.51	0.003
Post-bronchodilator FVC L	3.20±0.84	3.05±0.91	3.01±0.96	0.005
FEV₁ % predicted	51±15	49±16	48±15	0.009
Post-bronchodilator FEV₁/FVC %	46±12	45±11	45±11	0.445
BMI kg·m⁻²	27±5	27±6	26±6	0.190
Fat free mass index kg·m⁻²	53±12	52±13	50±13	0.009
6MWD m	395±116	385±115	377±127	0.142
Emphysema by CT (LAA%)	17±12	17±12	18±12	0.486
Oxygen saturation %	94.9±3.1	94.9±2.5	94.7±2.5	0.676
SGRQ total Score	44±18	47±18	49±19	0.002
FACIT fatigue score	37±10	36±10	36±10	0.106
mMRC score	1.4±1.0	1.6±1.0	1.7±1.1	0.006
BODE index	2.6±1.9	2.9±2.0	3.2±2.2	0.001
WBCs ×10⁹ L⁻¹	7.5±2.0	7.9±2.1	8.1±2.2	<0.001
Exacerbation rate^#	0.75±1.18	0.86±1.23	0.85±1.09	0.232
COPD hospitalisation rate^¶	0.13±0.47	0.18±0.53	0.18±0.57	0.245
Cardiovascular disease	30	33	32	0.679
History of osteoporosis	14	11	11	0.428
Diabetes	11	8	9	0.272
GORD	26	25	27	0.840
Statin use	34	28	27	0.094
Inhaled corticosteroid use	89	92	92	0.362
Oral corticosteroid use	0	1	0	n/a
IL-6 pg·mL⁻¹	1.9 (0.4–4.2)	1.9 (0.4–4.0)	2.2 (0.6–5.1)	0.476
IL-8 pg·mL⁻¹	6.2 (2.8–11.2)	7.0 (3.5–12.4)	8.3 (4.2–14.9)	0.004
Fibrinogen mg·dL⁻¹	443 (384–511)	442 (387–507)	443 (393–510)	0.951
Club cell protein 16 ng·mL⁻¹	5.4 (3.8–7.3)	4.7 (3.4–6.5)	4.7 (3.1–6.4)	<0.001
SP-D ng·mL⁻¹	123 (8–168)	115 (84–162)	122 (87–174)	0.224
CRP mg·L⁻¹	3.0 (1.5–6.1)	3.2 (1.7–7.3)	3.5 (1.6–7.0)	0.147
CCL-18 ng·mL⁻¹	112 (87–140)	102 (79–132)	101 (81–123)	<0.001
Longitudinal Changes
FEV₁decline mL·year⁻¹	31±48	35±44	30±42	0.209
COPD exacerbations PPPY⁺	1.06±1.18	1.15±1.27	1.07±1.31	0.277
COPD hospitalisations PPPY⁺	0.16±0.38	0.22±0.49	0.23±0.45	0.283
6MWD change over 3 years m	-15±90	-20±103	-20±87	0.626
Emphysema by CT (LAA%) change^§	1.3±4.5	1.8±4.9	2.7±5.0	0.010
SGRQ total score change⁺	0.2±12.5	1.6±12.8	-1.6±14.3	0.007

Date are presented as mean±sd, % or median (interquartile range), unless otherwise stated. FEV₁: forced expiratory volume in 1 s; FVC: forced vital capacity; BMI: body mass index; 6MWD: 6-min walking distance; CT: computed tomography; LAA%: % low-attenuation areas; SGRQ: St George’s Respiratory Questionnaire; FACIT: Functional Assessment of Chronic Illness Therapy; mMRC: modified Medical Research Council; BODE: BMI, airflow obstruction, dyspnoea, exercise capacity; WBCs: white blood cells; COPD: chronic obstructive pulmonary disease; GORD: gastro-oesophageal reflux disease; IL: interleukin; SP-D: surfactant protein D; CRP: C-reactive protein; CCL-18: chemokine ligand 18; PPPY: per person per year; n/a: not applicable. ^#: in the year prior to entry; ^¶: in the prior year; ⁺: over 3 years; ^§: change in LAA% reflects year 3 value minus baseline value.