Effects of resistance exercise training on acyl-ghrelin and obestatin levels in hemodialysis patients

Figures & data

Figure 1. Flowchart of patients throughout the study.

Table 1. Comparison of biochemistry and anthropometric data before and after 6 months of resistance training exercise program (RETP) between exercise and control group.

	Exercise group (N = 37)		Control group (N = 15)
	Baseline	After	Baseline	After
Biochemical parameters
Acyl-ghrelin (pg/mL)	20.8 (14.4–26.8)	31.2 (24.7–45.3)^a	41.6 (33.8–64)^c	36.4 (32–46)
Obestatin (ng/mL)	3.0 (2.7–3.0)	1.5 (1.2–2.8)^a	2.9 (2.8–3.0)	2.9 (2.7–3.0)^d
Acyl-ghrelin/obestatin ratio	7.2 (5.7–9.2)	19.1 (15.0–25.6)^b	14.1 (10.9–21.5)^c	13.3 (11.3–14.6)^d
Albumin (g/dL)	3.7 ± 0.3	3.9 ± 0.2^a	4.1 ± 0.3^b	4.3 ± 0.4^b
Creatinine (mg/dL)	12.4 ± 3.5	12.3 ± 3.3	8.0 ± 3.0^c	10.1 ± 2.8
Kt/V	1.4 ± 0.3	1.3 ± 0.4	1.4 ± 0.4	1.4 ± 0.4
Hemoglobin (g/dL)	10.9 ± 1.6	10.5 ± 1.4	11.3 ± 1.6	11.6 ± 1.7
Anthropometric parameters
BMI (kg/m^2)	23.5 ± 3.9	24.0 ± 4.3^a	25.3 ± 3.5	25.4 ± 3.4
Arm muscular area (cm^2)	27.2 ± 6.6	28.6 ± 6.0^a	28.7 ± 7.3	27.8 ± 9.3
Fat mass (%)	29.7 ± 6.7	28.9 ± 5.8	33.1 ± 7.9	34.5 ± 7.6^b
Fat-free mass (kg)	45.1 ± 11.1	46.7 ± 10.7^a	45.4 ± 9.2	44.5 ± 8.9

Notes: RETP, resistance exercise training program; BMI, body mass index; parametric tests use for mean values and non parametric tests used for median values; non-normally distributed variables presented as median (15th percentile and 75th percentile); normally distributed variables presented as mean ± SD.

^ap < 0.05 intragroup, paired t test.

^bp < 0.001 intergroup, paired t test to independent samples (parametric or non-parametric tests).

^cp < 0.05 intergroup, paired t test to independent samples.

^dp < 0.05 intragroup, paired t test.

Table 2. Quality of life evaluation before and after 6 months of exercise and control group.

	Exercise group (N = 37)		Control group (N = 15)
	Before	After	Before	After
SF-36 quality of life
Physical function	85 (70–95)	100 (80–100)	100 (62–100)	80 (52–100)
Role physical	50 (25–100)	100 (50–100)^a	50 (25–100)	50 (25–100)^b
Body pain	100 (62–100)	84 (61–100)	61 (49–100)	61 (49–100)
Vitality	70 (50–80)	75 (60–95)	77 (65–80)	77 (65–80)
General health	70 (45–87)	70 (45–82)	74 (67–88)	74 (67–88)
Mental health	100 (100–100)	100 (100–100)	86 (76–97)	80 (62–97)
Role mental	88 (68–100)	96 (68–100)	100 (33–100)	100 (83–100)
Social function	100 (50–100)	100 (87.5–100)	100 (62–100)	80 (52–100)

Notes: Form Survey 36 questions. Median, interquartile range values tested by non-parametric Wilcoxon Signed Ranks Test. Mean, standard deviation values tested with paired sample T-test. Significances level, p < 0.05.

^aIntragroup difference; ^bIntergroup difference.

Table 3. Simple linear regression model examining the effects of the variables that presented significant changes after resistance exercise training program of exercise group on acyl-ghrelin and obestatin changes independent of resistance exercise training program.

	Acyl-ghrelin change^b		Obestatin change^b
Change^a	Beta coefficient (95% CI)	p Value	Beta coefficient (95% CI)	p Value
Obestatin	0.07 (−0.84 to 0.97)	0.88	–	–
Acyl-ghrelin	–		−0.003 (−0.02 to 0.03)	0.79
Albumin	−2.64 (−8.44 to 3.17)	0.38	−1.47 (−2.85 to −0.09)	0.05
Role physical (SF-36)	0.08 (−0.21 to 0.37)	0.60	0.02 (−0.11 to 0.16)	0.69
BMI	−5.84 (−12.60 to 0.92)	0.10	0.76 (−1.19 to 2.71)	0.45
AMA	1.15 (−2.28 to 4.58)	0-.05	−1.32 (−2.06 to −0.59)	0.001
Body fat	0.38 (−1.49 to 2.25)	0.70	0.75 (0.29 to 1.21)	0.003
FFM	−0.01 (−1.73 to 1.71)	0-.99	0.25 (−0.22 to 0.72)	0.31

Notes: BMI, Body Mass Index; AMA, arm muscle area; FFM, fat-free mass.

^a,bSimple Linear Regression Model based on variable change = [(value after RETP−value before RETP)/value before RETP].