Low Liver Density Is Linked to Cardiovascular Comorbidity in COPD: An ECLIPSE Cohort Analysis

Figures & data

Figure 1 Example of a computed tomography slice before (Panel A) and after segmentation (Panel B).

Table 1 Characteristics of Patients with COPD and Control Subjects

	COPD (n = 1554)	Controls (n = 387)	p value^†
Age (years)	63.6 (0.2)	55.0 (0.5)	<0.001
BMI (kg/m^2)	26.1 (0.1)	26.6 (0.2)	0.04
Liver attenuation (HU)	58.7 (9.2)	58.9 (9.0)	0.61
Male, n (%)	948 (61)	174 (45)	<0.001
Smoking status
Current smokers, n (%)	575 (37.0)	139 (36)	<0.001
Former smokers, n (%)	995 (64.0)	93 (24.0)
Never smokers, n (%)	–	155 (40.1)
Pack/year	48.4 (0.7)	18.3 (1.1)	<0.001
Pulmonary Function
FEV1 (% pred)	43.5 (0.4)	108.0 (0.7)	<0.001
FVC (L)	2.77 (0.02)	4.15 (0.05)	<0.001
FEV1/FVC	0.44 (0.01)	0.77 (0.01)	<0.001
GOLD stage
2, n (%)	663 (42.7)	–	–
3, n (%)	675 (43.4)	–	–
4, n (%)	216 (13.9)	–	–
Clinical variables
SGRQ total score	49.2 (0.5)	7.5 (0.6)	<0.001
Hypertension, n (%)	595 (38.3)	23.0 (5.9)	<0.001
Diabetes, n (%)	138 (8.9)	5.5 (1.4)	0.03
Coronary artery disease, n (%)	361 (23.2)	39 (10.0)	<0.001
Heart failure, n (%)	90 (5.8)	3 (0.8)	<0.001
Stroke, n (%)	59 (3.8)	6 (1.6)	0.03
Death during follow-up (n)	139 (8.9)	19 (4.9)	<0.001

Notes: Values are mean (SE) unless stated otherwise. ^†p-value for Chi² or Student’s t-test. Significant p-values are shown in bold.

Abbreviations: HU, Hounsfield Units; BMI, body mass index; FEV₁, forced expiratory volume in 1 s; FVC, forced vital capacity; GOLD, global initiative for chronic Obstructive Lung Disease (severity scale); SGRQ, St-George Respiratory Questionnaire.

Figure 2 Liver attenuation distribution among patients with COPD and control subjects. p>0.05 for all comparisons.

Abbreviation: COPD, chronic obstructive pulmonary disease

Table 2 Characteristics of COPD Patients by Liver Attenuation Quartile

	Quartile 1 [< 54.6 HU] (n=386)	Quartile 2 [54.6 to 60.4 HU] (n=391)	Quartile 3 [60.4 to 64.9 HU] (n=389)	Quartile 4 [> 64.9 HU] (n=388)	p value^†
Liver attenuation (HU)	46.05 (0.40)	57.90 (0.08)	62.64 (0.07)	68.32 (0.16)	<0.001
Demographics
Age	63.8 (0.4)	64.2 (0.3)	63.0 (0.4)	63.2 (0.4)	0.07
Sex (% male)	270 (69.9)	266 (68.0)	210 (53.9)	202 (52.1)	<0.001
BMI	28.6 (0.3)	26.2 (0.3)	25.0 (0.2)	24.4 (0.2)	<0.001
Current smokers (%)	131 (33.9)	133 (34.0)	147 (37.8)	163 (42)	0.06
Pack-year	52 (2)	48 (1)	47 (1)	47 (1)	0.04
Pulmonary function
FEV1(% pred)	44.8 (0.8)	42.9 (0.8)	42.5 (0.7)	44.0 (0.8)	0.13
FVC (L)	2.88 (0.04)	2.85 (0.05)	2.68 (0.04)	2.66 (0.04)	<0.001
FEV1/FVC	0.45 (0.01)	0.43 (0.01)	0.43 (0.01)	0.44 (0.01)	0.06
GOLD stage
2, n (%)	176 (45,6)	161 (41,2)	156 (40,1)	170 (43,8)
3, n (%)	160 (41, 5)	169 (43, 2)	179 (46,0)	167 (43,0)	0.69
4, n (%)	50 (13,0)	61 (15,6)	54 (13,9)	51 (13,1)
Health status and functional tests
SGRQ score	49 (1)	49 (1)	49 (1)	50 (1)	0.60
mMRC score	1.6 (0.1)	1.7 (0.1)	1.6 (0.1)	1.7 (0.1)	0.64
6MWT (m)	361 (6)	375 (7)	384 (6)	370 (6)	0.08
Baseline comorbidities
Hypertension, n (%)	168 (43.5)	154 (39.5)	150 (37.6)	127 (32.7)	0.03
Diabetes, n (%)	57 (14.7)	36 (9.1)	26 (6.6)	21 (5.5)	<0.001
Coronary artery disease, n (%)	113 (29.2)	97 (24.7)	77 (19.4)	75 (19.4)	<0.01
Heart failure, n (%)	30 (7.8)	19 (4.8)	23 (5.9)	18 (4.6)	0.21
Stroke, n (%)	24 (6.3)	11 (2.9)	12 (2.9)	12 (3.2)	0.03
Follow-up
Death, n (%)	135 (35)	160 (41)	123 (31)	124 (32)	0.61
Exacerbation rate (n by year)	1.13	1.23	1.37	1.33	0.04

Notes: Values are expressed with mean ± SE unless stated otherwise. ^†p-value for Chi² or ANOVA. Significant p-values are shown in bold.

Abbreviations: BMI, body mass index; FEV₁, forced expiratory volume in 1 s; FVC, forced vital capacity; SGRQ, St-George Respiratory Questionnaire; mMRC, modified Medical Research Council Dyspnea Scale; 6MWT, 6-min walking test.

Figure 3 Unadjusted and adjusted odds ratios to present cardiovascular comorbidity in the lowest liver density quartile vs the highest liver density quartile.

Figure 4 Inflammatory marker levels showing differences according to liver attenuation groups (A-D). Values are expressed with mean ± standard errors. 1 is the group with the lowest liver attenuation and 4 the group with the greatest liver attenuation. p-value for ANCOVA corrected for age, sex, Body Mass Index and smoking status.

Abbreviations: CRP, C-reactive protein; IL6, and interleukin-6.