Sarcopenia Is an Independent Risk Factor for NAFLD in COPD: A Nationwide Survey (KNHANES 2008–2011)

Figures & data

Figure 1 A flow diagram of the study subjects in the KNHANES IV and V (2008–2011).

Abbreviations: ALT, alanine aminotransferase; AST, aspartate aminotransferase; BMI, body mass index; COPD, chronic obstructive pulmonary disease; DXA, dual-energy X-ray absorptiometry; HBV, hepatitis B virus; HCV, hepatitis C virus; NAFLD, nonalcoholic fatty liver disease.

Table 1 Characteristics of COPD Patients According to NAFLD Status

Variables	All (n = 850)	No NAFLD (n = 726, 85.4%)	NAFLD (n = 124, 14.6%)	P-value
Age (years)	65.0 ± 9.6	65.4 ± 9.5	63.0 ± 10.2	0.010
Male sex	581 (68.4)	498 (68.6)	83 (66.9)	0.713
BMI (kg/m^2)	23.5 ± 2.8	22.9 ± 2.4	27.0 ± 2.6	<0.001
Waist circumference (cm)	84.1 ± 8.8	82.5 ± 7.8	93.6 ± 7.3	<0.001
Smoking status				0.485
Never smoker	435 (51.2)	371 (51.1)	64 (51.6)
Ex-smoker	178 (20.9)	148 (20.4)	30 (24.2)
Current smoker	237 (27.9)	207 (28.5)	30 (24.2)
ASM (kg)	18.2 ± 4.0	17.8 ± 3.9	19.6 ± 4.4	<0.001
ASM/BMI (m^2)	0.8 ± 0.2	0.8 ± 0.2	0.7 ± 0.2	<0.001
Sarcopenia_BMI	174 (20.5)	131 (18.0)	43 (34.7)	<0.001
ASM/BW (%)	29.2 ± 4.0	29.5 ± 4.0	27.3 ± 3.8	<0.001
Sarcopenia_BW	181 (21.3)	130 (17.9)	51 (41.1)	<0.001
ASM/height^2	6.8 ± 1.0	6.7 ± 1.0	7.3 ± 1.0	<0.001
Sarcopenia_height	278 (32.7)	234 (32.2)	44 (35.5)	0.476
Metabolic syndrome	309 (36.4)	224 (30.9)	85 (68.5)	<0.001
Hypertension	413 (48.6)	342 (47.1)	71 (57.3)	0.001
Diabetes mellitus	144 (16.9)	95 (13.1)	49 (39.5)	<0.001
Pulmonary Function Test
FVC (%)	89.0 ± 15.5	89.7 ± 15.5	85.3 ± 15.3	0.004
FEV1 (%)	76.3 ± 16.4	76.6 ± 16.8	74.9 ± 13.9	0.240
Ratio of FEV1/FVC (%)	0.6 ± 0.1	0.6 ± 0.1	0.6 ± 0.1	0.002
Systolic blood pressure (mmHg)	125.0 ± 16.8	124.5 ± 16.8	128.4 ± 16.6	0.017
Diastolic blood pressure (mmHg)	75.1 ± 10.3	74.5 ± 10.3	78.3 ± 9.7	<0.001
Total cholesterol (mg/dL)	190.2 ± 36.1	190.9 ± 35.5	186.5 ± 39.3	0.211
HDL cholesterol (mg/dl)	45.0 ± 10.5	45.6 ± 10.6	41.7 ± 9.3	<0.001
Triglyceride (mg/dl)	146.7 ± 93.6	139.7 ± 84.2	187.1 ± 129.4	<0.001
AST (IU/L)	23.1 ± 8.5	22.8 ± 8.0	25.0 ± 10.8	<0.001
ALT (IU/L)	21.1 ± 12.1	19.0 ± 9.4	33.1 ± 18.0	0.025
Platelet (×10^9/L)	246.1 ± 60.2	246.7 ± 59.9	242.7 ± 62.0	0.497
Glucose (mg/dl)	102.1 ± 23.6	99.7 ± 20.7	116.2 ± 32.7	<0.001

Note: Data are mean ± standard error (range) or number (percentage).

Abbreviations: ALT, alanine aminotransferase; ASM, appendicular skeletal muscle mass; AST, aspartate aminotransferase; BMI, body mass index; BW, body weight; COPD, chronic obstructive pulmonary disease; FEV₁, forced expiratory volume in 1 sec; FVC, force vital capacity; HDL, high-density lipoprotein; NAFLD, nonalcoholic fatty liver disease.

Table 2 Association Between Sarcopenia and NAFLD in COPD Patients

	Sarcopenia_BMI OR (95% CI)	P value	Sarcopenia_BW OR (95% CI)	P value	Sarcopenia_Height OR (95% CI)	P value
Unadjusted	1.74 (1.09–2.77)	0.020	2.44 (1.47–4.03)	<0.001	1.16 (0.78–1.72)	0.476
Multivariable Model 1	2.69 (1.59–4.55)	<0.001	2.99 (1.82–4.95)	<0.001	1.15 (0.77–1.72)	0.500
Multivariable Model 2	2.59 (1.53–4.39)	<0.001	2.88 (1.73–4.81)	<0.001	1.01 (0.73–1.65)	0.659
Multivariable Model 3	2.19 (1.29–3.72)	<0.004	2.57 (1.51–4.39)	<0.001	1.01 (0.70–1.70)	0.692
Multivariable Model 4	1.95 (1.11–3.46)	0.022	2.25 (1.30–3.92)	0.004	1.06 (0.67–1.68)	0.800

Notes: The multivariable model was not adjusted for ASM and BMI, as these variables were used for calculating definition of sarcopenia. Model 1 = adjusted for age, gender. Model 2 = model 1 + forced vital capacity. Model 3 = model 2 + hypertension, diabetes mellitus. Model 4 = model 3 + metabolic syndrome

Abbreviations: ASM, appendicular skeletal muscle mass; BMI, body mass index; BW, body weight; CI, confidence interval; COPD, chronic obstructive pulmonary disease; NAFLD, nonalcoholic fatty liver disease; OR, odds ratio.

Figure 2 Prevalence of NAFLD in patients with COPD based on the GOLD grade. (A) GOLD I, II, III, and IV; (B) GOLD I, and II–IV.

Abbreviations: COPD, chronic obstructive pulmonary disease; GOLD, global initiative for chronic obstructive lung disease; NAFLD, nonalcoholic fatty liver disease.

Figure 3 Association between sarcopenia and fibrotic burden in NAFLD patients (n = 124) according to the definitions of sarcopenia. (A) Sarcopenia_BMI; (B) sarcopenia_BW.

Abbreviations: BMI, body mass index; BW, body weight; NAFLD, nonalcoholic fatty liver disease; NFS, NAFLD fibrosis score.