Respiratory infectious phenotypes in acute exacerbation of COPD: an aid to length of stay and COPD Assessment Test

Figures & data

Figure 1 Strategies for screening patients with AECOPD.

Abbreviations: AECOPD, acute exacerbation of COPD; CAT, COPD Assessment Test.

Table 1 Baseline characteristics, clinical features at study entry, and outcomes in 81 patients with COPD exacerbation

Variable	All patients	Viral infection	Bacterial infection	Coinfection	Non-infectious group
	(n=81; 100%)	(n=31; 38%)	(n=10; 12%)	(n=7; 9%)	(n=33; 41%)
Baseline characteristics
Age, years	71±10	69±10	74±6	71±6	72±10
Male sex, n (%)	61 (75)	24 (70)	6 (60)	6 (86)	25 (75)
BMI, kg/m^2	22±5	22±5	22±5	21±3	22±4
Smoking status
Current smoker, n (%)	10 (12)	2 (6)	0 (0)	0 (0)	8 (24)
Smoking, pack-years*	19±19	15±19	27±20	28±24	17±17
Co-morbidities, n (%)	32 (39.50)	12 (38.70)	4 (40.00)	3 (42.85)	13 (39.39)
Charlson’s index	1.5±0.8	1.4±0.7	1.5±1.0	1.3±0.5	1.6±1.0
GOLD class (n, groups A, B, C, D)	17/17/29/18	7/7/11/6	2/1/4/3	2/1/3/1	6/8/11/8
LTOT, n (%)	14 (17)	5 (16)	2 (20)	1 (14)	6 (18)
LOS, days	9.6±4.1	10.1±3.0	11.3±4.0	16.9±5.2	7.0±2.0
CAT, scores	26.0±6.4	25.1±5.5	25.5±7.0	32.0±4.5	25.0±5.6
FEV1, L	1.2±0.6	1.1±0.6	1.2±0.5	1.0±0.4	1.3±0.6
FEV1, % of predicted normal value	54.0±26.8	52.1±27.0	56.5±27.4	42.3±17.6	57.4±28.1
FEV1/FVC, %	55.4±8.9	56.0±7.6	56.9±10.3	51.2±10.1	55.1±9.6

Notes: Data are presented as number (%) or mean ± SD.

* (Number of cigarettes per day × number of years of smoking)/20.

Abbreviations: BMI, body mass index; GOLD, Global initiative for chronic Obstructive Lung Disease; LTOT, long-term oxygen therapy; LOS, length of stay; CAT, COPD Assessment Test; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity.

Figure 2 Viruses detected by RVP kit from the nasopharyngeal samples of 81 patients admitted for AECOPD were influenza virus (n=21), enterovirus/rhinovirus (n=11), coronavirus (n=9), bocavirus (n=6), metapneumovirus (n=5), parainfluenza virus types 1, 2, 3, and 4 (n=3), and RSV (n=3).

Abbreviations: RVP, respiratory virus panel; AECOPD, acute exacerbation of COPD; RSV, respiratory syncytial virus.

Figure 3 Statistical distribution (box plot) of LOS according to the four respiratory infectious phenotypes: 0 – non-infectious group, 1 – viral infection, 2 – bacterial infection, 3 – coinfection.

Notes: The longitudinal axis of the picture above represents the days of stay in hospital. The central box represents the value from the lower to the upper quartile (25%–75%). The middle line inside the box represents the median value. The lines extend from the minimum to the maximum values, excluding outliers that are displayed as separate points. An outlier is defined as a value that is smaller than the lower quartile minus 1.5 times the interquartile range, or larger than the upper quartile plus 1.5 times the interquartile range. These values are plotted with a • marker.
Abbreviation: LOS, length of stay.

Figure 4 Statistical distribution (box plot) of CAT scores according to the four respiratory infectious phenotypes: 0 – non-infectious group, 1 – viral infection, 2 – bacterial infection, 3 – coinfection.

Abbreviation: CAT, COPD Assessment Test.

Figure 5 Pearson’s correlations between CAT and LOS.

Note: Solid line, CAT vs LOS: r=0.372, P<0.05.
Abbreviations: LOS, length of stay; CAT, COPD Assessment Test.