Association of neutrophil-lymphocyte ratio with all-cause and cardiovascular mortality in peritoneal dialysis patients: A systematic review and meta-analysis

Table 1 Risk of bias assessment using the Joanna Briggs Institute tool

Criteria	An et al[19]	Liu et al[18]	Zeng et al[17]	Zhang et al[16]	Xu et al[15]	Lau et al[14]	Liu[13]
Similar groups from the same population	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Exposures measured similarly	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Exposure is measured validly and reliably	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Confounding factors identified	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Strategies to deal with confounding factors	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Groups are free of outcome at the start	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Outcomes are measured validly and reliably	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Follow-up time reported and sufficient	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Follow up complete or reason for loss described	Yes	Yes	Yes	Yes	Yes	Yes	Unclear
Strategies to address incomplete follow-up	Yes	Yes	Yes	Yes	Yes	Yes	Unclear
Appropriate statistical analysis	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Overall appraisal	Include	Include	Include	Include	Include	Include	Include

Table 2 Baseline characteristics of population from included studies- demographics, n (%)

Ref.	Study type	Country	Duration in years (n)	Follow up in years (n)	Sample size (n)	Age in years (mean ± SD)	Males	Body mass index (kg/m2) (mean ± SD)
An et al[19]	P	China	2	4	138	53 ± 17	81 (58.7)	21.9 ± 2.7
Liu et al[18]	R	China	7	9	1778	47.4 ± 15.6	1058 (59.5)	21.5 ± 3.0
Zeng et al[17]	R	China	7.5	3	1502	51 ± 15.5a	852 (56.7)a	22.1 ± 3.04
Zhang et al[16]	P	China	5.4	2.4	140	54.7 ± 15.7a	84 (57.1)	23.47 ± 3.7
Xu et al[15]	P	China	15	N/A	378	N/A	N/A	N/A
Lau et al[14]	R	China	2	1	225	59 ± 12.3	129 (57.3)	N/A
Liu[13]	R	China	1	N/A	189	N/A	N/A	N/A

^aP value < 0.05.

N/A: Not applicable; P: Prospective; R: Retrospective.

Table 3 Baseline characteristics of study population from included studies- blood parameters and comorbidities, n (%)

Ref.	Serum albumin (g/dL) (mean ± SD)	Absolute neutrophil (109/L) (mean ± SD)	Absolute lymphocytes (109/L) (mean ± SD)	Leukocytes (109/L) (mean ± SD)	Neutrophil-to-lymphocyte ratio (mean ± SD)	Hemoglobin (g/dL) (mean ± SD)	C-reactive protein (mg/dL) (mean ± SD)	Cholesterol (mg/dL) (mean ± SD)	Diabetes mellitus
An et al[19]	3.9 ± 0.5	5.0 ± 1.7a	1.5 ± 0.5a	N/A	3.33 ± 3.4	100.2 ± 20.3	1.3 ± 0.9a	216.6 ± 58	33 (23.9)
Liu et al[18]	3.7 ± 0.5	N/A	N/A	6.6 ± 0.52	2.87 ± 0.3	101 ± 21	N/A	189 ± 11	449 (25.3)
Zeng et al[17]	3.5 ± 0.5a	4.1 ± 1.6a	1.2 ± 0.52a	6.1 ± 2.0a	3.3 ± 1.5a	8.7 ± 1.9a	N/A	162.4 ± 42.9	342 (22.8)
Zhang et al[16]	3.5 ± 5	4.4 ± 2.1a	1.4 ± 0.6a	6.5 ± 2.4a	2.87 ± 0.4	8.8 ± 2.2	3.15 ± 1.7	162.02 ± 44.9	31 (22)
Xu et al[15]	3 ± 0	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
Lau et al[14]	3.5 ± 0.4	4.6 ± 2.0a	1.1 ± 0.4a	6.6 ± 2.2a	3.9 ± 3.06a	8.9 ± 1.3	0.41 ± 0.3	N/A	115 (51.1)
Liu[13]	3 ± 0	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A

^aP value < 0.05.

N/A: Not applicable.

Table 4 Subgroup meta-analysis for all-cause mortality

Variables	Number of studies	Number of patients	Adjusted hazard ratio (95%CI)	P value	I2
Study design
Prospective	3	656	1.06 (0.58-1.97)	0.84	83.6
Retrospective	3	2129	1.10 (1.00-1.21)	0.047	77
Sample size
< 350	4	692	1.27 (0.74-2.15)	0.38	84.8
≥ 350	3	3658	1.11 (1.03-1.19)	0.004	61.3
Males
< 59	2	1640	0.90 (0.37-2.18)	0.81	90.1
≥ 59	3	2143	1.08 (1.02-1.14)	0.01	45.8
Diabetes
< 32	3	1780	1.18 (0.55-2.56)	0.67	85.4
≥ 32	2	2003	1.07 (1.04-1.10)	< 0.0001	< 0.0001
Neutrophil-to-lymphocyte ratio (109/L)
2.87-3.2	2	1918	1.47 (0.64-3.41)	0.37	72.2
3.3-3.89	3	1865	0.99 (0.69-1.42)	0.96	80.4
Serum albumin (g/dL)
< 3.5	3	2069	1.42 (1.01-1.99)	0.04	76.4
≥ 3.5	4	2281	1.05 (0.95-1.17)	0.32	73.6