Circulating Biomarkers of Handgrip Strength and Lung Function in Chronic Obstructive Pulmonary Disease

Figures & data

Table 1 Baseline Characteristics of the Study Participants

	Men				Women
	Non-COPD	GOLD-1	COPD GOLD-2	GOLD-3 and 4	Non-COPD	GOLD −1	COPD GOLD-2	GOLD-3 and 4
Age category (years)
56–65, n (%)	212 (56.6)	115 (52.7)	58 (47.9)	12 (50)	227 (54.8)	132 (52.5)	71 (47.6)	17 (54.8)
66–75, n (%)	162 (43.4)	103 (47.3)	63 (52.1)	12 (50)	187 (45.2)	119 (47.5)	78 (52.4)	14 (45.2)
Smoking status
Non-smokers, n (%)	103 (27.5)	34 (15.6)	17 (14.1)	4 (16.6)	403 (97.3)	236 (94)	146 (98)	29 (93.5)
Ex-smoker, n (%)	182 (48.6)	57 (26.1)	41 (33.8)	13 (54.1)	7 (1.7)	11 (4.4)	2 (1.3)	1 (3.2)
Current, n (%)	89 (23.8)	127 (58.2)	63 (52.1)	7 (29.1)	4 (0.9)	4 (1.6)	1 (0.7)	1 (3.2)
BMI (Kg/m^2) (Mean ± SD)	24.3 ± 2.3	24.1 ± 3.4	23.8 ± 2	24 ± 3.3	25.1 ± 3.8	24.5 ± 2.1	24.8 ± 2.7	24.4 ± 3.3
Waist Circum. (cm) (Mean ± SD)	85.3 ± 9.3	84.2 ± 8.3	83.3 ± 10	84.3 ± 4.3	87.3 ± 5.3	84.1 ± 7.3	84.7 ± 6.3	83.9 ± 9.3
FEV1 (L) (Mean ± SD)	2.78 ± 0.5	2.24 ± 0.6	1.66 ± 0.4	1.36 ± 0.3	2.75 ± 0.4	2.2 ± 0.4	1.59 ± 0.3	1.26 ± 0.3
FEV1% predicted (Mean ± SD)	97.2 ± 4.4	78.5 ± 7.3	58.3 ± 8.8	47.6 ± 8.1	98.5 ± 3.6	79.1 ± 6.2	57 ± 9.3	45.3 ± 6.1
Diabetes, n (%)	16 (4.4)	13 (5.9)	15 (12.4)	5 (20.8)	13 (3.8)	17 (6.7)	16 (10.7)	5 (16.1)
Dyslipidemia, n (%)	61 (16.3)	37 (16.9)	31 (25.6)	9 (37.5)	44 (10.6)	39 (15.5)	36 (24.1)	9 (29)
Hypertension, n (%)	17 (4.5)	22 (10.1)	12 (9.9)	4 (16.6)	11 (2.6)	23 (9.1)	19 (12.7)	4 (12.9)
Anemia, n (%)	36 (9.6)	42 (19.2)	29 (23.9)	8 (33.3)	53 (12.8)	34 (13.5)	27 (18.1)	10 (32.2)

Figure 1 (A) Absolute and adjusted hand-grip strength for age, smoking status, waist circumference, anemia, hypertension and serum HDL-C in subjects with non-COPD and COPD by GOLD grades. Values are expressed as mean ± SD; one-way analysis of variance. * p < 0.05 vs women participants of the same group, ^# p < 0.05 vs non-COPD participants of the same gender. Relationship of the FEV₁% with the absolute (B) and adjusted hand-grip strength (C) in the men and women participants with and without COPD.

Figure 2 (A) Hand-grip strength according to smoking status in the men and women participants of different age groups; Values are expressed as mean ± SD; one-way analysis of variance. * p < 0.05 vs 66–75 old participants of the same gender, ^# p < 0.05 vs non-smokers of the same gender and age group. (B) relationship of the serum HDL-C with the hand-grip strength and (C) FEV₁% in men and women participants of the non-COPD and COPD groups. Hand-grip strength was adjusted for age, smoking status, waist circumference, anemia and hypertension in all analyses.

Table 2 Classification of the COPD Participants According to EQ-5D Scores and Association with Hand-Grip Strength and FEV₁%

EQ-5D Descriptive Scores	Men			Women
	N (%)	Absolute Hand-Grip Strength (kg) (Mean ± SD)	FEV1% (Mean ± SD)	N (%)	Absolute Hand-Grip Strength (kg) (Mean ± SD)	FEV1% (Mean ± SD)
Mobility
No problem	221 (66.9)	47.2± 5.2	82.3± 9.3	209 (61.3)	31.8± 3.4	79.2± 6.6
Some problem	87 (26.3)	43.7± 3.3*	61.6± 5.3*	81 (23.7)	26.4± 4.1*	58.5± 5.4*
Extreme problem	22 (6.6)	37.1± 3.9*^,#	43.2± 7.7*^,#	51 (15)	24.8± 3.3*	48.6± 4.7*^,#
Self-care
No problem	251 (76.1)	49± 4.6	77.2± 7.3	268 (78.9)	29.2± 3.3	75.6± 4.7
Some problem	65 (19.7)	42.2± 2.8*	65.9± 5.6*	54 (15.8)	26.3± 3.9*	60.4± 4.2*
Extreme problem	14 (4.2)	36.1± 3.3*^,#	46.7± 6.3*^,#	19 (5.6)	25.1± 5.3*	45.2± 3.3*^,#
Usual activities
No problem	189 (57.3)	48.6± 4.4	79.1± 8.3	257 (75.4)	30.3± 3.8	83.2± 6.5
Some problem	103 (31.2)	43.7± 5.1*	59± 4.4*	63 (18.5)	27.1± 5.3*	61.7± 4.7*
Extreme problem	38 (11.5)	39.2± 3.9*	48.4± 5.1*^,#	21 (6.1)	23.9± 4.3*^,#	47.2± 5.3*^,#
Pain/discomfort
No problem	237 (71.8)	48.9± 6.3	79.5± 7.1	197 (57.7)	31.1± 4.3	76.3± 6.4
Some problem	61 (18.5)	42.2± 5.2*	61.2± 5.3*	105 (30.8)	27.9± 3.3*	59± 5.3*
Extreme problem	32 (9.7)	38.6± 4.9*	52.4± 6.3*^,#	39 (11.4)	24.1± 4.3*^,#	50.1± 5*^,#
Anxiety/depression
No problem	203 (61.5)	47.7± 4.8	81.4± 6.2	235 (68.9)	32.2± 5.3	79.1± 6.9
Some problem	109 (33)	41.6± 4.9*	59.2± 4.3*	73 (21.4)	27.9± 3.6*	62.8± 4.3*
Extreme problem	18 (5.4)	35.7± 5.5*	49.6± 4.3*^,#	23 (6.7)	22.6± 4.3*^,#	46.7± 3.5*^,#

Notes: Values are Expressed as Mean ± SD; One-Way Analysis of Variance. * p < 0.05 Vs Subgroup with “no Problem” of the Same EQ-5D Parameter of the Same Gender, ^# p < 0.05 Vs Subgroup with “some Problem” of the Same EQ-5D Parameter in the Same Gender.

Table 3 Protein Expression of the Serum Biomarkers of TSA, AGP, CC16 and HDL-C in the Sera of Participants with and Without COPD

	Men				Women
	Non-COPD	GOLD-1	COPD GOLD-2	GOLD-3 and 4	Non-COPD	GOLD-1	COPD GOLD-2	GOLD-3 and 4
TSA (mg/dl)	51.4 ± 3.6	52.5 ± 2.1	57.4 ± 3.8*^,#	60.1 ± 3.4*^,#	51.1 ± 3.1	51.6 ± 2.6	55 ± 3.8*^,#	57 ± 3.3*^,#
AGP (g/l)>	0.794 ± 0.04	0.743 ± 0.07	0.936 ± 0.04	0.963 ± 0.05^#	0.813 ± 0.05	0.846 ± 0.07	0.833 ± 0.06	0.783 ± 0.05
CC16 (ng/mL)	23.53 ± 3.2	21.66 ± 4.13	16.7 ± 3.51*^,#	12.05 ± 2.09*^,#	24.68 ± 4.06	21.33 ± 3.71	17.36 ± 2.82*^,#	15.15 ± 2.94*^,#
HDL-C (mg/dl)	42.92 ± 2.34	41.96 ± 1.97	39.36 ± 3.46	31.71 ± 3.65*^,#,φ	41.68 ± 3.18	40.27 ± 3.21	37.26 ± 2.14	34.21 ± 3.24*^,#

Notes: Values are Expressed as Mean ± SD; One-Way Analysis of Variance. *p < 0.05 Vs Non-COPD Group of the Same Gender; ^#p < 0.05 Vs GOLD-1 Subgroup of the Same Gender; ^φp < 0.05 Vs GOLD-2 Subgroup of the Same Gender.

Figure 3 Linear regression graphs of the hand-grip strength and FEV₁% with serum biomarkers of TSA (A, B), AGP (C, D) and CC16 (E, F) in the men and women participants with and without COPD. Hand-grip strength was adjusted for age, smoking status, waist circumference, anemia and hypertension in all analyses.