Does chronic kidney disease affect the complications and prognosis of patients after primary colorectal cancer surgery?

Table 2 Summary of characteristics between chronic kidney disease group and Non-chronic kidney disease group

Characteristics	Studies	Participants (CKD/non-CKD)	Mean difference/odds ratio (95%CI)	Heterogeneity
Baseline information
Male	9	952/46819	0.92 (0.63, 1.35); P = 0.67	I2 = 82%; P < 0.01
Age, yr	3	190/796	8.67 (5.73, 11.61); P < 0.01	I2 = 60%; P = 0.08
ASA1-ASA2	3	218/2443	0.10 (0.03, 0.34); P < 0.01	I2 = 88%; P < 0.01
ASA3-ASA4	3	218/2443	10.27 (2.98, 35.35); P < 0.01	I2 = 88%; P < 0.01
T0-T2	4	508/2962	0.71 (0.46, 1.08); P = 0.11	I2 = 55%; P = 0.08
T3-T4	4	508/2962	1.41 (0.92, 2.16); P = 0.11	I2 = 55%; P = 0.08
N0	4	508/2962	1.09 (0.89, 1.33); P = 0.42	I2 = 0%; P = 0.40
N1-N3	4	508/2962	0.92 (0.75, 1.33); P = 0.42	I2 = 0%; P = 0.40
Surgery-related information
Colon cancer	4	409/2055	2.10 (0.91, 4.85); P = 0.08	I2 = 80%; P < 0.01
Rectal cancer	4	409/2055	0.48 (0.21, 1.10); P = 0.08	I2 = 80%; P < 0.01
Laparoscopy surgery	6	566/44809	0.88 (0.54, 1.42); P = 0.59	I2 = 72%; P < 0.01
Open surgery	6	566/44809	1.14 (0.70, 1.86); P = 0.59	I2 = 72%; P < 0.01
Emergency operation	2	324/42342	1.31 (0.84, 2.05); P = 0.23	I2 = 0%; P = 0.49
Operative time	3	309/1096	-3.58 (-18.95, 11.79); P = 0.65	I2 = 60%; P = 0.08
Intraoperative blood loss	3	309/1096	1.40 (-30.34, 33.15); P = 0.93	I2 = 0%; P = 0.96
Postoperative complications
Overall complication	7	738/44407	1.78 (0.64, 4.94); P = 0.27	I2 = 95%; P < 0.01
Specific complications
Cardiovascular	4	641/43612	3.39 (2.34, 4.91); P < 0.01	I2 = 36%; P = 0.20
Anastomotic leakage	4	508/2962	1.44 (0.89, 2.32); P = 0.14	I2 = 35%; P = 0.21
Pulmonary infection	5	607/44891	2.70 (1.82, 4.00); P < 0.01	I2 = 0%; P = 0.84
Intestinal obstruction	5	420/2971	0.89 (0.58, 1.37); P = 0.60	I2 = 6%; P = 0.37
Surgical site infection	6	685/45109	1.29 (1.00, 1.65); P = 0.05	I2 = 0%; P = 0.86
Other site infection	3	515/43030	1.07 (0.64, 1.80); P = 0.79	I2 = 0%; P = 0.60
Postoperative bleeding	3	347/2200	0.63 (0.17, 2.36); P = 0.49	I2 = 0%; P = 0.50
Short-term death	4	650/44169	3.01 (2.20, 4.11); P < 0.01	I2 = 0%; P = 0.50

CKD: Chronic kidney disease; ASA: American Society of Anesthesiologists; T: Tumor; N: Node.