Effect of Zinc Supplementation on Maintenance Hemodialysis Patients: A Systematic Review and Meta-Analysis of 15 Randomized Controlled Trials

Table 4

Results of intervention time subgroup.

Factor	Intervention time	Number of studies	Heterogeneity test			Weighted mean difference
					value	WMD	[95% CI]	value
Serum zinc (ug/dL)	<50 days			85.90%	<0.001		,
	50–60 days			0.00%			,	<0.001
	>60 days			12.90%			,	<0.001
BMI (kg/m2)	60 days			13.70%			,	0.838
	90 days		-	-	-		,
nPNA (g/kg/d)	<50 days			0.00%			,
	≥50 days			31.10%			,
Dietary protein intake (g/kg/d)	<50 days			0.00%			,
	≥50 days			0.00%			,	<0.001
Albumin (g/dL)	<60 days			45.60%			,
	≥60 days			47.40%			, 1
Hemoglobin (g/dL)	<60 days			0.00%			,
	≥60 days			72.90%			,
HDL (mg/dL)	<60 days			96.80%	<0.001		,
	≥60 days			90.10%			,
LDL (mg/dL)	<60 days			49.00%			,	<0.001
	≥60 days			95.90%	<0.001		,
TC (mg/dL)	<60 days			33.20%			,
	≥60 days			91.00%	<0.001		,
TG (mg/dL)	<60 days		-	-	-		,
	≥60 days			8.60%			,
CRP (ng/mL)	<60 days			14.60%			,
	≥60 days		-	-	-		,	<0.001
MDA (nmol/mL)	<60 days		-	-	-		,	<0.001
	≥60 days			0.00%			,	<0.001
SOD (U/g Hb)	<60 days		-	-	-		,	<0.001
	≥60 days		-	-	-		,

Note. -: values could not be calculated due to an insufficient number of studies; , and WMD was considered statistically significant.