Determinants of elevated healthcare utilization in patients with COPD

Respiratory Research

Table 2 Comparison of characteristics between entire cohort and the subset group.

Variable	Entire cohort	The subset group	P value
N	389	177
Age (yrs)*	68 (59 - 77)	67 (60 - 74)	0.25^†
Males (%)	77.6%	78.0%	0.93^‡
BMI (kg/m²)*	27 (24 - 31)	27 (23 - 30)	0.57^†
Pack yrs smoking (yrs)*	50 (30 - 80)	40 (28 - 60)	0.07^†
FEV₁ (% predicted)*	47 (37 - 60)	46 (36 - 58)	0.49^†
GOLD class 3 or 4	54.0%	59.9%	0.19^‡
Age adjusted CCI*	7 (4 - 9)	6 (4 - 9)	0.71^†
Annualized healthcare cost*	2200 (1139 - 4934)	2312 (1139 - 5519)	0.61^†

Abbreviations: BMI- body mass index, FEV₁- forced expired volume in one second (as percent predicted), GOLD- global initiative for chronic obstructive lung disease, CCI- Charlson Comorbidity Index.
* median (25-75 percentiles); ^† Mann-Whitney U test; ^‡ Chi-square test.

ISSN: 1465-993X