High prevalence of bronchiectasis in emphysema-predominant COPD patients

Figures & data

Table 1 Characteristics of COPD patients

Variables	n=1,739
Age, years	68.57±9.76
Sex, male/female, %	79.8/20.2
BMI, kg/m^2	23.42±3.97
Smokers, n, %	1,288, 74.1
Smoking history, pack-years	31.43±30.13
PFT
FVC, L	2.63±0.93
FEV1, L	1.49±0.72
FEV1 % predicted, %	52.80±21.93
FEV1/FVC%, %	54.94±12.61
GOLD I/II/III/IV, %	12.8/38.1/31.7/17.4
%LAA-950, %	13.58±13.26
Comorbidity, n (%)
Tuberculosis	196 (11.3)
Ischemic heart disease	421 (24.2)
Pulmonary hypertension	47 (2.7)
Cor pulmonale	290 (16.7)
Hypertension	537 (30.9)
Diabetes mellitus	165 (9.5)
Arrhythmia	169 (9.7)
Cancer	711 (40.9)
Bronchiectasis	140 (8.1)

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

Abbreviations: BMI, body mass index; GOLD, global initiative for chronic obstructive lung disease; %LAA-950, percentage of lung voxels with CT attenuation value below −950 HU; PFT, pulmonary function test.

Figure 1 Flow diagram of the study.

Abbreviations: CT, computed tomography; EI, emphysema index; HRCT, high-resolution computed tomography.

Table 2 Comparison between subjects with and without bronchiectasis

Variables	COPD with bronchiectasis, n=140	COPD without bronchiectasis, n=1,599	P-value
Age, years	68.3±9.1	68.6±9.8	0.497a
Male, n (%)	102 (72.9)	1,285 (80.4)	0.034b
BMI, kg/m^2	23.4±4.0	23.4±4.0	0.872c
Smokers, n (%)	96 (68.6)	1,192 (74.5)	0.099b
Smoking history, pack-years	29.1±29.1	31.6±30.2	0.369a
Blood tests
ALB, g/L	36.7±5.5	37.7±5.3	0.046a
ESR, mm/h	23.1±19.6	24.8±23.6	0.888a
Fib, g/L	3.7±1.3	3.6±2.1	0.231a
PFT
FVC, L	2.2±0.8	2.7±0.9	<0.001a
FEV1, L	1.1±0.5	1.5±0.7	<0.001a
FEV1 % predicted	41.9±17.9	53.8±22.0	<0.001a
FEV1/FVC%	49.5±12.2	55.4±12.5	<0.001a
Comorbidity, n (%)
Tuberculosis	11 (7.9)	185 (11.6)	0.183b
Ischemic heart disease	31 (22.1)	390 (24.4)	0.552b
Pulmonary	9 (6.4)	38 (2.4)	0.005b
hypertension
Hypertension	38 (27.1)	499 (31.2)	0.318b
Cor pulmonale	33 (23.6)	257 (16.1)	0.022b
Diabetes mellitus	18 (12.9)	147 (9.2)	0.156b
%LAA-950	15.0±12.0	13.4±13.4	0.011a

Notes: Data are presented as mean ± SD for continuous variables and percentage for categorical variables.

a Analysis by Mann–Whitney U-test.

b Analysis by chi-square test.

c Analysis by Student’s t-test.

Abbreviations: ALB, albumin; BMI, body mass index; ESR, erythrocyte sedimentation rate; Fib, fibrinogen; %LAA-950, percentage of lung voxels with CT attenuation value below −950 HU; PFT, pulmonary function test.

Table 3 Comparison of characteristics between emphysema-predominant group and non-emphysema-predominant group

Characteristics	Emphysema-predominant group, n=369	Non-emphysema-predominant group, n=418	P-value
Age, years	69.9±9.1	68.2±10.2	0.014a
Male, n (%)	317 (85.9)	303 (72.5)	<0.001b
BMI, kg/m^2	22.5±4.1	24.5±3.8	<0.001a
Smokers, n (%)	299 (81.0)	277 (66.3)	<0.001b
Smoking history, pack-years	34.3±29.6	27.0±29.9	<0.001c
Blood tests
ALB, g/L	37.7±4.7	39.2±4.6	<0.001a
WBC, 10^9/L	8.2±3.2	7.5±3.0	0.002c
NEU, %	71.2±14.5	67.9±14.0	0.001a
EOS, %	1.7±3.0	2.1±4.8	0.007c
ESR, mm/h	19.5±19.2	20.5±18.6	0.252c
Fib, g/L	3.5±1.3	3.4±1.3	0.112c
PFT
FVC, L	2.3±0.7	2.6±0.9	<0.001a
FEV1, L	1.0±0.5	1.6±0.7	<0.001c
FEV1 % predicted	38.0±17.5	56.7±19.8	<0.001c
FEV1/FVC%	45.1±10.9	59.0±10.8	<0.001c
Comorbidity, n (%)
Tuberculosis	39 (10.6)	29 (6.9)	0.070b
Ischemic heart disease	81 (22.0)	120 (28.7)	0.030b
Pulmonary hypertension	19 (5.1)	8 (1.9)	0.013b
Hypertension	105 (28.5)	147 (35.2)	0.044b
Cor pulmonale	109 (29.5)	46 (11.0)	<0.001b
Diabetes mellitus	27 (7.3)	52 (12.4)	0.017b
Bronchiectasis	61 (16.5)	43 (10.3)	0.010b
%LAA-950	24.5±12.0	4.0±2.8	<0.001c

Notes: Data are presented as mean ± SD for continuous variables and percentage for categorical variables.

a Analysis by Student’s t-test.

b Analysis by chi-square test.

c Analysis by Mann–Whitney U-test.

Abbreviations: ALB, albumin; BMI, body mass index; EOS, eosinophil; ESR, erythrocyte sedimentation rate; Fib, fibrinogen; %LAA-950, percentage of lung voxels with CT attenuation value below −950 HU; NEU, neutrophil; PFT, pulmonary function test; WBC, white blood cell.

Figure 2 Correlation between the severity of bronchiectasis and airflow limitation or emphysema.

Notes: (A) Correlation between Bhalla score and FEV₁% predicted. (B) Correlation between Bhalla score and emphysema index.

Table 4 Logistic regression analysis for predictors of bronchiectasis among COPD subjects

Variables	Adjusted (model 1)		Adjusted (model 2)
	OR (95% CI)	P-value	OR (95% CI)	P-value
Female	1.413 (0.715–2.789)	0.320	1.390 (0.709–2.725)	0.338
Age	0.899 (0.483–1.671)	0.736	0.913 (0.491–1.697)	0.774
Smokers	0.732 (0.392–1.367)	0.328	0.734 (0.395–1.365)	0.329
ALB	0.919 (0.481–1.755)	0.797	0.858 (0.451–1.634)	0.642
FEV1 % predicted	1.636 (1.219–2.197)	0.001	NA
%LAA-950	NA		1.993 (1.199–3.313)	0.008

Abbreviations: ALB, albumin; NA, not applicable; %LAA-950, percentage of lung voxels with CT attenuation value below −950 HU.