Impact of radiologically stratified exacerbations: insights into pneumonia aetiology in COPD

Respiratory Research

Table 3 Baseline characteristics of subjects grouped by the presence/absence of at least one exacerbation with pneumonic infiltrate

Characteristic	Subjects with no pneumonic infiltrate identified at any exacerbation (n = 81)			Subjects with ≥1 pneumonic infiltrate identified at exacerbation (n = 46)			P-value
Characteristic	n^a			n^a			P-value
Age (years)	81	66.9	(8.4)	46	66.6	(9.1)	0.843
Male sex, n (%)	81	44	(54.3)	46	24	(52.2)	0.855
Current smokers, n (%)	81	34	(42.0)	46	20	(43.5)	0.508
Body mass index (kg/m²)	81	27.8	(5.5)	46	27.5	(5.5)	0.764
FEV1 (Litres)	80	1.26	0.47	46	1.08	(0.99)	0.036
FEV1 (% predicted)	80	49.2	(15.7)	46	41.7	(13.0)	0.007
TLCO (mmol/kPa/min)*	78	4.99	(2.78)	44	3.85	(1.30)	0.005
6MWD (meters)	79	320.1	(110.8)	46	256.6	(100.9)	0.002
CAT score	80	16.3	(7.8)	46	17.5	(7.3)	0.399
Prior history of pneumonia (before study enrolment)	79	22	(27.8)	46	21	(45.7)	0.043
Influenza vaccination during the year prior to enrolment	81	72	(88.9)	46	42	(91.3)	0.786
ICS use	81	69	(85.2)	46	44	(95.7)	0.083
Bacteria detected (culture)	69	34	(49.3)	41	23	(56.1)	0.311
Bacteria detected (PCR)	62	35	(56.5)	40	28	(70.0)	0.169

Continuous variables presented as mean (SD) and categorical variables as n (%) unless otherwise stated. * presented as median (IQR)
FEV1 forced expiratory volume in 1 s, TLCO transfer factor for carbon monoxide, 6MWD 6 min walk distance, CAT COPD Assessment Test, ICS inhaled corticosteroid, PCR polymerase chain reaction
^aindicates the number of subjects with available data/samples for each characteristic
*P-values comparing the subject groups using the independent sample t-test or Mann Whitney U test where appropriate for continuous variables and the Chi-square test for categorical variables

ISSN: 1465-993X