Depression, 5HTTLPR and BDNF Val66Met polymorphisms, and plasma BDNF levels in hemodialysis patients with chronic renal failure

Figures & data

Table 1 Demographic characteristics of hemodialysis patients with and without MDD

	Without MDD (n=143)	With MDD (n=45)	Statistic	P-value
Age (years)	58.9±14.0	57.4±13.8	t=0.627	0.532
Male/female, n (%)	70 (49.0)/73 (51.0)	19 (42.2)/26 (57.8)	χ^2=0.622	0.495
Smoke, n (%)	32 (22.4)	6 (13.3)	χ^2=1.736	0.210
Alcohol use, n (%)	15 (10.5)	6 (13.3)	χ^2=0.279	0.787
Current antidepressant treatment, n (%)	4 (2.8)a	6 (13.3)b	χ^2=7.275	0.015*
Body mass index (kg/m^2)	23.2±4.0	23.7±4.2	t=0.678	0.499
Hemodialysis duration (months)	70.6±68.4	52.8±51.6	t=1.601	0.111
Number of comorbid diseases	1.9±1.5	2.2±2.0	t=0.667	0.507
Depression score in HADS	4.7±4.3	11.9±5.8	t=7.644	<0.001***
Anxiety score in HADS	3.7±3.4	7.5±4.8	t=4.943	<0.001***
Fatigue score in CFS	22.4±6.8	31.6±7.7	t=7.619	<0.001***
Physical component summary in SF-36	53.9±26.2	47.1±28.6	t=1.481	0.140
Mental component summary in SF-36	75.3±24.5	38.1±26.5	t=8.595	<0.001***

Notes:

a Amitriptyline (n=4);

b amitriptyline (n=2), mirtazapine (n=2), escitalopram (n=1), paroxetine (n=1);

* P<0.05;

*** P<0.001.

Abbreviations: CFS, Chalder Fatigue Scale; HADS, Hospital Anxiety and Depression Scale; MDD, major depressive disorder; SF-36^®, the Short-Form Health survey (health-related quality of life).

Table 2 Genotype distribution of the 5HTTLPR and BDNF Val66Met polymorphism in hemodialysis patients

	5HTTLPR genotype						χ^2	P-value	BDNF Val66Met genotype			χ^2	P-value
	S/S	S/LG	LG/LG	S/LA	LG/LA	LA/LA			Val/Val	Val/Met	Met/Met
No MDD, n (%)	77 (53.8)	6 (4.2)	3 (2.1)	48 (33.6)	6 (4.2)	3 (2.1)	1.466	0.953	36 (25.2)	60 (42.0)	47 (32.9)	1.194	0.539
MDD, n (%)	22 (48.9)	2 (4.4)	1 (2.2)	18 (40.0)	2 (4.4)	0 (0)			12 (26.7)	22 (48.9)	11 (24.4)
	Non-LA carrier			LA carrier			χ^2	P-value	Non-Met carrier	Met carrier		χ^2	P-value
No MDD, n (%)	86 (60.1)			57 (39.9)			0.297	0.606	36 (25.2)	107 (74.8)		0.040	0.846
MDD, n (%)	25 (55.6)			20 (44.4)					12 (26.7)	33 (73.3)

Abbreviations: 5HTTLPR, 5′ flanking transcriptional region of the serotonin transporter gene; BDNF, brain-derived neurotrophic factor; L, long; L_A, long A; L_G, long G; MDD, major depressive disorder; Met, methionine; S, short; Val, valine; Val66Met, Val-to-Met substitution at codon 66.

Table 3 The plasma BDNF level determined in relation to major depressive disorder (MDD), sex, current antidepressant treatment, 5HTTLPR genotype and BDNF Val66Met genotype among hemodialysis patients

Characteristics	Plasma BDNF level (pg/mL)	Statistic	P-value
MDD
Without MDD (n=143)	748.4±217.6	t=0.355	0.723
With MDD (n=45)	762.1±222.0
Sex
Male (n=89)	719.7±222.9	t=2.004	0.047*
Female (n=99)	783.6±205.9
Current antidepressant treatment
Without (n=178)	752.1±217.4	Z=0.363	0.716
With (n=10)	789.1±173.6
5HTTLPR genotype
Non-LA carrier (n=111)	755.3±222.3	t=0.207	0.837
LA carrier (n=77)	748.5±211.1
BDNF Val66Met genotype
Non-Met carrier (n=48)	771.1±190.3	t=0.651	0.516
Met carrier (n=140)	746.6±224.1

Note:

* P<0.05.

Abbreviations: 5HTTLPR, 5′ flanking transcriptional region of the serotonin transporter gene; BDNF, brain-derived neurotrophic factor; L_A, long A; MDD, major depressive disorder; Met, methionine; Val, valine; Val66Met, Val-to-Met substitution at codon 66.