Risk Factors and Relation with Mortality of a New Acquisition and Persistence of Pseudomonas aeruginosa in COPD Patients

Figures & data

Figure 1. Consort diagram of the study.

Figure 2. Association network for first PA isolation (Panel A) and PA persistence (Panel B). For network description and further information, see text.

Table 1. Baseline and follow-up characteristics of patients with a first isolation of PA vs. those without any during follow-up.

	All patients (n = 170)	First PA isolation (n = 41)	No PA isolation (n = 129)	P value
At recruitment
Males, %	91.2%	98%	89%	0.099
Age, years	70.1 ± 9.1	71.4 ± 8.4	69.5 ± 9.2	0.233
Body mass index, Kg/m^2	27.8 ± 4.8	26.8 ± 4.5	28.3 ± 5	0.078
Cumulative smoking exposure, pack-year	55.3 ± 29.3	78.6 ± 32.4	48.2 ± 28.9	0.011
Current smokers, %	12.4%	12.2%	12.4%	0.851
Dyspnea, mMRC	1.52 ± 1	1.66 ± 0.9	1.50 ± 1	0.124
Daily sputum production, n (%)	60.6%	75.6%	55.8%	0.024
Chronic mucopurulent or purulent sputum	31.2%	38.4%	29.2%	0.145
CT Bronchiectasis	62.9%	70%	61%	0.096
FEV1/FVC, %	52.4 ± 11.9	47.7 ± 11.8	55.6 ± 11.9	0.009
Post-bronchodilator FEV1, % predicted	50.1 ± 12	45.2 ± 14	51.7 ± 11.6	0.011
Charlson Index	2.2 ± 1.4	2.1 ± 1.5	2.3 ± 1.4	0.482
Chronic treatment, n (%)
Anticholinergics	80%	88%	78%	0.182
Long-acting β2-adrenergics	64.2%	47%	62.1%	0.213
Inhaled steroids	42%	44%	41%	0.752
Combined therapy*	71%	73%	69%	0.614
Triple therapy	57.8%	63.4%	55.8%	0.394
Home oxygen therapy	22.1%	34%	19%	0.051
Inhaled antibiotics	0%	0%	0%	--
Macrolides	1.8%	2.5%	1.5%	0.821
Oral steroids	2.6%	7%	1%	0.016
Albumin, mg/dl	4.2 ± 0.4	4.2 ± 0.4	4.2 ± 0.4	0.966
US-CRP, IU/ml*	3.7 (1.6-6.6)	5.3 (2.4-7.9)	3.5 (1.4-6.5)	0.177
Fibrinogen, mg/dl	394 ± 136	446.2 ± 145	382 ± 133	0.001
During follow-up
Annual exacerbation rates
Total exacerbations	0.94 ± 0.9	1.87 ± 1.3	0.84 ± 0.8	0.009
Moderate exacerbations	0.79 ± 1	1.11 ± 1.3	0.61 ± 0.9	0.01
Severe exacerbations (hospital admission)	0.33 ± 0.6	0.76 ± 1.0	0.23 ± 0.4	0.003
Previous single isolation of any PPM**	28.4%	56.1%	25.8%	0.002
Previous repeated isolation of PPM, n (%)**	13.1%	21.9%	10.9%	0.07
Previous isolation of HI, n (%)**	24.3%	51.2%	20.9%	<0.001

* Combined therapy: Long-acting β2 adrenergic bronchodilator + inhaled corticosteroid.

** Previous to the isolation of PA. Repeated is define as more than 1 isolation of the same PPM.

Table 2. Factors associated with first isolation of PA identified by the Cox multivariate analysis, ordered by Hazard Ratio (HR) values.

Variable	Β coefficient	P value	HR	95%CI
Previous HI isolation	1.047	0.002	2.85	1.51-5.50
Previous severe exacerbations	0.406	0.0001	1.50	1.23-1.83
Fibrinogen level, mg/dl	0.023	0.06	1.41	0.99-3.12
Cumulative smoking exposure, pack-year	0.013	0.005	1.01	1-1.02
Post-BD FEV1, % reference	−0.026	0.042	0.97	0.95-0.99

Table 3. Baseline and follow-up characteristics of patients with single PA isolate vs. PA persistence (≥2 isolations).

	Single PA isolation (n = 17)	PA persistence (n = 24)	P value
At recruitment
Males, %	92%	100%	0.239
Age, years	68.2 ± 8.5	73.7 ± 7.6	0.037
Body mass index, Kg/m2	26.6 ± 4.6	26.9 ± 4.5	0.875
Cumulative smoking exposure, pack-year	61.1 ± 22	54.4 ± 15.7	0.536
Current smokers, %	17.6%	12.5%	0.498
Dyspnea, mMRC	1.47 ± 1.1	1.79 ± 0.9	0.040
Daily sputum production, n (%)	58.8%	87.5%	0.024
Chronic mucopurulent or purulent sputum	42.8%	65.2%	0.081
Bronchiectasis	71%	96%	0.024
FEV1/FVC, % predicted	47 ± 13.9	48.2 ± 10.4	0.753
Post-bronchodilator FEV1, ml	1,296 ± 454	1,171 ± 553	0.456
% predicted	45.7 ± 15.3	44.9 ± 13.4	0.869
Charlson Index	2.2 ± 1.6	2 ± 1.5	0.687
Albumin, mg/dl	4.3 ± 0.2	4.1 ± 0.4	0.121
US-CRP, IU/ml*	4 (1.2-8.5)	6.5 (3.1-9.9)	0.215
Fibrinogen, mg/dl	383 ± 99	410 ± 66	0.359
During follow-up
Annual exacerbations rates
Total exacerbations	0.75 ± 0.5	2.72 ± 1.4	0.008
Moderate exacerbations	0.53 ± 0.8	1.31 ± 1.5	0.018
Severe exacerbations (hospital admission)	0.22 ± 0.3	1.41 ± 1.3	<0.001
Previous single isolation by any PPM**	52.9%	58.3%	0.740
Previous repeated isolation by any PPM, n (%)**	12.9%	19.9%	0.099
Previous isolation of HI, n (%)**	30.7%	41.4%	0.079
Chronic treatment, n (%)
Anticholinergic	100%	79%	0.046
Long-acting beta-adrenergic	58.5%	53%	0.833
Inhaled steroids	41%	46%	0.344
Combined therapy*	71%	75%	0.614
Triple therapy	70.5%	58.3%	0.435
Home oxygen therapy	41.1%	59.1%	0.242
Inhaled antibiotics	70.6%	25%	0.003
Macrolides	88.2%	45.8%	0.005
Oral steroids	0%	13%	0.083

* Combined therapy: Long-acting β2 adrenergic bronchodilator + inhaled corticosteroid.

** Previous to the isolation of PA.

Table 4. Factors associated with persistence of PA identified by the Cox multivariate analysis, ordered by Hazard Ratio (HR) values.

Variable	β coefficient	P value	HR	95%CI
CT bronchiectasis	1.96	0.012	7.11	1.53-12.34
Previous severe exacerbations	0.23	0.033	1.19	1.04-1.46
Inhaled antibiotic treatment	−9.14	0.035	0.42	0.15-0.85

Figure 3. All-cause mortality Kaplan Meier curves. Panel A: Patients with single PA isolation (green line) vs. no PA isolation (blue line). Panel B. Patients with PA persistence during follow-up (green line) vs. no PA isolation (blue line). For further explanations, see text.