Evaluation of Efficacy of Mirtazapine on Pruritus and Serum Histamine and Serotonin Levels in Patients Undergoing Hemodialysis: A Before–After Pilot Clinical Trial

Figures & data

Table 1 The Demographic and Relevant Clinical Data of the Patients at the Beginning of the Study

Age, Years	Mean ± SD Range	61.11 ± 10.39 37–84
Sex, N (%)	Male	15 (55.6%)
	Female	12 (44.4%)
Causes for which patients undergoing HD, N (%)	Diabetes mellitus	13 (48.15%)
	Hypertension	7 (25.93%)
	Chronic glomerulonephritis	2 (7.41%)
	Un-known	4 (14.61%)
	Other	1 (3.70%)
Duration of HD therapy, years	Mean ± SD	5.8 ± 3.9
	Range	1–18
Duration suffering from pruritus, years	Mean ± SD	3.5 ± 2.8
	Range	1–10
Values of relevant laboratory data
Hg (g dL^−1)	Mean ± SD	12.25 ± 1.91
	Range	10–13.6
WBC (cell mm^3)	Mean ± SD	5230 ± 2340
	Range	2500–8200
PLT (10^3 µL^−1)	Mean ± SD	213.45 ± 85.60
	Range	138–427
Calcium (mg dL^−1)	Mean ± SD	8.85 ± 0.62
	Range	6.9–9.8
Phosphorus (mg dL^−1)	Mean ± SD	4.75 ± 0.58
	Range	2.8–4.8
Albumin (g dL^−1)	Mean ± SD	3.74 ± 0.58
	Range	3.3–5.2
iPTH (g dL^−1)	Mean ± SD	249.22 ±80.15
	Range	150–350
KtV^−1	Mean ± SD	1.29 ± 0.08
	Range	1.2–1.5
Creatinine (mg dL^−1)	Mean ± SD	8.8 ± 3.8
	Range	5.9–12.3

Abbreviations: HD, hemodialysis; Hg, hemoglobin; WBC, white blood cells; PLT, Platelet; iPTH, intact parathyroid hormone; KtV⁻¹, Kt stands for dialyzer clearance multiplied by time (mL min⁻¹) and V for volume of water a patient’s body contains.

Figure 1 Changes of pruritus severity based on the visual analogue scale (VAS) at different time points during the study (P-value<0.001).

Table 2 The Values of VAS and SIS at Different Time Points During the Study

Time	VAS scores	P-Value	SIS scores	P-Value
Day 1	8.48 ± 1.01		8.07±1.43
Day 3	6.93 ± 1.21		6.06±1.07
Day 5	4.44 ± 1.45	<0.001	5.22± 1.15	<0.001
Day 7	2.93 ± 1.39		4.44± 0.97
Day 9	2.29 ±0.98		4.11± 1.01
Day 11	1.78 ± 0.89		3.41±0.92
Day 14	1.04 ±0.79		2.81± 0.74

Note: Values represent as mean ± SD.

Abbreviations: VAS, visual analogue scale; SIS, sleep interference score.

Table 3 Distribution of Severity of Pruritus by 4-Point Classification System Before and After Treatment with Mirtazapine

VAS Severity	None n (%)	Mild n (%)	Moderate n (%)	Severe n (%)	P-value
Before treatment	0 (0)	0 (0)	7 (25.9)	20 (74.1)	<0.001
After treatment	7 (25.9)	17 (63.0)	3 (11.2)	0 (0)

Figure 2 Mean sleep interference score at different time points during the study period (P-value<0.001).

Table 4 Serum Levels of Histamine and Serotonin Before and After the Treatment

Variable	Before Treatment	After Treatment	P-value
Histamine (ng/mL)	25.40±8.21	22.48±7.07	0.006
Serotonin (ng/mL)	92.44±27.79	85.80±30.67	0.10

Note: Values represented as mean ± SD.