Effects of early diet resumption on the incidence of complications following polypectomy: A randomized controlled trial

Table 1 Characteristics of patients who underwent polypectomy in experimental group and control group, n (%)

Characteristic	Experimental group (n = 751)	Control group (n = 751)	P value
Age (year) (mean ± SD)	57.6 ± 10.7	57.2 ± 11.3	0.387
Sex			0.122
Male	455 (60.6)	484 (64.4)
Female	296 (39.4)	267 (35.6)
Smoking history	205 (27.3)	204 (27.2)	0.954
Drinking history	111 (14.8)	133 (17.7)	0.124
Hypertension	267 (35.6)	283 (37.7)	0.391
Diabetes	89 (11.9)	75 (10.0)	0.247
Cardio-cerebral vascular disease	59 (7.9)	58 (7.7)	0.923
Body mass index (kg/m2) (mean ± SD)	24.0 ± 3.1	24.0 ± 3.1	0.708
Polyp number [median (P25, P75)]	2 (1, 4)	2 (1, 4)	0.910
Polyp size (cm) [median (P25, P75)]	0.9 (0.8, 1.0)	1.0 (0.8, 1.1)	0.307
Pedunculated polyp	197 (26.2)	199 (26.5)	0.907
Polyp location			0.332
Right colon (caecum, ascending colon)	157 (20.9)	168 (22.4)
Transverse colon (liver flexure, transverse colon, spleen flexure)	234 (31.2)	208 (27.7)
Left colon (descending colon, sigmoid colon, rectum)	360 (47.9)	375 (49.9)
Duration of polypectomy (minutes) [median (P25, P75)]	21 (15, 30)	21 (16, 31)	0.131
Polypectomy modality			0.688
Cold forceps polypectomy and cold snare polypectomy	86 (11.5)	87 (11.6)
Hot snare polypectomy and endoscopic mucosal resection	650 (86.6)	644 (85.8)
Hybrid endoscopic submucosal dissection	15 (2.0)	20 (2.7)

Table 2 Clinical outcomes of patients in experimental group and control group following polypectomy, n (%)

Characteristic	Total (n = 1502)	Experimental group (n = 751)	Control group (n = 751)	P value
DPPB	76 (5.1)	35 (4.7)	41 (5.5)	0.480
Major bleeding	27 (1.8)	11 (1.5)	16 (2.1)	0.332
The timing of DPPB (day) [median (P25, P75)]	2 (1, 3)	2 (1, 3)	2 (1, 3)	0.294
The timing of major bleeding (day) [median (P25, P75)]	2 (2, 3)	2 (1, 3)	2 (2, 3)	0.939
Post-polypectomy perforation	2 (0.1)	0 (0.0)	2 (0.3)	0.479
Post-polypectomy hypoglycemia	14 (0.9)	3 (0.4)	11 (1.5)	0.032a
Post-polypectomy fever	38 (2.5)	16 (2.1)	22 (2.9)	0.324
post-polypectomy length of stay (day) [median (P25, P75)]	1 (1, 2)	1 (1, 2)	2 (1, 2)	< 0.001b

^aP < 0.05.

^bP < 0.01.

DPPB: Delayed post-polypectomy bleeding.

Table 3 Subgroup analysis of patients with single polyp or multiple polyps in experimental group and control group, n (%)

Characteristic	Single polyp (n = 491)			Multiple polyps (n = 1011)
	Experimental group (n = 244)	Control group (n = 247)	P value	Experimental group (n = 507)	Control group (n = 504)	P value
Age (years) (mean ± SD)	54.3 ± 12.0	52.9 ± 11.9	0.193	59.2 ± 9.7	59.2 ± 10.4	0.979
Sex			0.498			0.134
Male	117 (48.0)	126 (51.0)		338 (66.7)	358 (71.0)
Female	127 (52.0)	121 (49.0)		169 (33.3)	146 (29.0)
Duration of polypectomy (minute) [median (P25, P75)]	15 (12, 21)	17 (13, 21)	0.018a	25 (18, 33)	25 (19, 33)	0.479
Polyp size (cm) [median (P25, P75)]	0.8 (0.7, 1.0)	0.8 (0.8, 1.0)	0.392	1.0 (0.8, 1.1)	1.0 (0.8, 1.2)	0.457
Polypectomy modality			0.121			0.456
Cold forceps polypectomy and cold snare polypectomy	24 (9.8)	13 (5.3)		62 (12.2)	74 (14.7)
Hot snare polypectomy and endoscopic mucosal resection	215 (88.1)	226 (91.5)		435 (85.8)	418 (82.9)
Hybrid endoscopic submucosal dissection	5 (2.0)	8 (3.2)		10 (2.0)	12 (2.4)
DPPB	6 (2.5)	7 (2.8)	0.796	29 (5.7)	34 (6.7)	0.500
Major bleeding	2 (0.8)	3 (1.2)	1.000	9 (1.8)	13 (2.6)	0.381
The timing of DPPB (day) [median (P25, P75)]	2.5 (1.0, 4.8)	3.0 (1.0,4.0)	0.942	2.0 (1.0, 3.0)	2.0 (1.0, 3.0)	0.198
The timing of major bleeding (day) [median (P25, P75)]	4.0 (1.0, 7.0)	3.0 (2.0, 4.0)	1.000	2.0 (1.5, 3.0)	2 (1.5, 3.5)	0.889
Post-polypectomy perforation	0 (0.0)	0 (0.0)	-	0 (0.0)	2 (0.4)	0.476
Post-polypectomy hypoglycemia	0 (0)	3 (1.2)	0.251	3 (0.6)	8 (1.6)	0.127
Post-polypectomy fever	5 (2)	10 (4)	0.198	11 (2.2)	12 (2.4)	0.822
post-polypectomy length of stay (day) [median (P25, P75)]	1 (1, 1)	1 (1, 2)	< 0.001b	1 (1, 2)	2 (1, 2)	< 0.001b

^aP < 0.05.

^bP < 0.01.

DPPB: Delayed post-polypectomy bleeding.

Table 4 Subgroup analysis of patients with polyps’ size < 1 cm or polyps’ size ≥ 1 cm in experimental group and control group, n (%)

Characteristic	Polyp size < 1 cm (n = 784)			Polyp size ≥ 1 cm (n = 718)
	Experimental group (n = 395)	Control group (n = 389)	P value	Experimental group (n = 356)	Control group (n = 362)	P value
Age (years) (mean ± SD)	57.2 ± 10.6	56.2 ± 11.5	0.224	58.2 ± 10.8	58.2 ± 11.0	0.997
Sex			0.245			0.307
Male	239 (60.5)	251 (64.5)		216 (60.7)	233 (64.4)
Female	156 (39.5)	138 (35.5)		140 (39.3)	129 (35.6)
Duration of polypectomy (minute) [median (P25, P75)]	19 (14, 27)	19 (15, 28)	0.335	24 (17, 33)	25 (18, 33)	0.278
Polyp number [median (P25, P75)]	2 (1, 3)	2 (1, 3)	0.798	3 (1, 4)	3 (1, 4)	0.664
Polypectomy modality			0.824			0.829
Cold forceps polypectomy and cold snare polypectomy	68 (17.2)	68 (17.5)		18 (5.1)	19 (5.2)
Hot snare polypectomy and endoscopic mucosal resection	322 (81.5)	314 (80.7)		328 (92.1)	330 (91.2)
Hybrid endoscopic submucosal dissection	5 (1.3)	7 (1.8)		10 (2.8)	13 (3.6)
DPPB	12 (3)	12 (3.1)	0.970	23 (6.5)	29 (8.0)	0.423
Major bleeding	2 (0.5)	4 (1.0)	0.668	9 (2.5)	12 (3.3)	0.532
The timing of DPPB (day) [median (P25, P75)]	2.0 (1.3, 3.8)	2.5 (1.0, 4.0)	1.000	2.0 (1.0, 3.0)	2.0 (1.0, 2.5)	0.205
The timing of major bleeding (day) [median (P25, P75)]	1.0 (1.0, 1.0)	3.5 (1.5, 4.0)	0.134	3.0 (2.0, 3.5)	2.0 (2.0, 2.8)	0.273
Post-polypectomy perforation	0 (0.0)	2 (0.5)	0.246	0 (0.0)	0 (0.0)	-
Post-polypectomy hypoglycemia	1 (0.3)	7 (1.8)	0.072	2 (0.6)	4 (1.1)	0.697
Post-polypectomy fever	7 (1.8)	10 (2.6)	0.443	9 (2.5)	12 (3.3)	0.532
Post-polypectomy length of stay (day) [median (P25, P75)]	1.0 (1.0, 2.0)	1.0 (1.0, 2.0)	< 0.001b	1.0 (1.0, 2.0)	2.0 (1.0, 2.0)	< 0.001b

^aP < 0.05.

^bP < 0.01.

DPPB: Delayed post-polypectomy bleeding.

Table 5 Subgroup analysis of patients with neoplastic polyp or non-neoplastic polyp in experimental group and control group, n (%)

Characteristic	Neoplastic polyp (n = 1200)			Non-neoplastic polyp (n = 302)
	Experimental group (n = 581)	Control group (n = 619)	P value	Experimental group (n = 170)	Control group (n = 132)	P value
Age (years) (mean ± SD)	57.6 ± 10.7	57.2 ± 11.3	0.387	54.9 ± 12.4	53.8 ± 12.1	0.463
Sex			0.251			0.248
Male	354 (60.9)	397 (64.1)		101 (59.4)	87 (65.9)
Female	227 (39.1)	222 (35.9)		69 (40.6)	45 (34.1)
Duration of polypectomy (minute) [median (P25, P75)]	22 (16, 31)	22 (16, 31)	0.480	20 (14, 28)	21 (16, 31)	0.101
Polyp size (cm) [median (P25, P75)]	1.0 (0.8, 1.1)	1.0 (0.8, 1.1)	0.928	0.8 (0.7, 1.0)	0.8 (0.7, 1.0)	0.191
Polypectomy modality			0.537			0.872
Cold forceps polypectomy and cold snare polypectomy	59 (10.2)	69 (11.1)		27 (15.9)	18 (13.6)
Hot snare polypectomy and endoscopic mucosal resection	510 (87.8)	532 (85.9)		140 (82.4)	112 (84.8)
Hybrid endoscopic submucosal dissection	12 (2.1)	18 (2.9)		3 (1.8)	2 (1.5)
DPPB	27 (4.6)	32 (5.2)	0.676	8 (4.7)	9 (6.8)	0.430
Major bleeding	10 (1.7)	12 (1.9)	0.779	1 (0.6)	4 (3.0)	0.232
The timing of DPPB (day) [median (P25, P75)]	2.0 (1.0, 3.0)	2.0 (1.0, 3.0)	0.367	2.0 (2.0, 2.8)	2.0 (1.0, 4.0)	0.724
The timing of major bleeding (day) [median (P25, P75)]	2.5 (1.0, 3.3)	2.0 (2.0, 3.0)	0.864	2.0	3.0 (1.3, 4.0)	0.709
Post-polypectomy perforation	0 (0.0)	2 (0.3)	0.500	0 (0.0)	0 (0.0)	-
Post-polypectomy hypoglycemia	3 (0.5)	7 (1.1)	0.394	0 (0.0)	4 (3.0)	0.075
Post-polypectomy fever	10 (1.7)	18 (2.9)	0.174	6 (3.5)	4 (3.0)	1.000
Post-polypectomy length of stay (day) [median (P25, P75)]	1.0 (1.0, 2.0)	2.0 (1.0, 2.0)	< 0.001b	1.0 (1.0, 2.0)	2.0 (1.0, 2.0)	< 0.001b

^bP < 0.01.

DPPB: Delayed post-polypectomy bleeding.

Table 6 Subgroup analysis of patients who underwent different modalities of polypectomy in experimental group and control group, n (%)

Characteristic	Cold forceps polypectomy and cold snare polypectomy (n = 173)			Hot snare polypectomy and endoscopic mucosal resection (n = 1294)			Hybrid endoscopic submucosal dissection (n = 35)
	Experimental group (n = 86)	Control group (n = 87)	P value	Experimental group (n = 650)	Control group (n = 644)	P value	Experimental group (n = 15)	Control group (n = 20)	P value
Age (years) (mean ± SD)	58.7 ± 10.2	58.2 ± 11.2	0.758	57.6 ± 10.7	57.0 ± 11.4	0.363	55.6 ± 14.3	57.7 ± 10.1	0.613
Sex			0.377			0.215			0.506
Male	58 (67.4)	64 (73.6)		390 (60.0)	408 (63.4)		7 (46.7)	12 (60.0)
Female	28 (32.6)	23 (26.4)		260 (40.0)	236 (36.6)		8 (53.3)	8 (40.0)
Duration of polypectomy (minute) [median (P25, P75)]	20 (13, 32)	21 (16, 32)	0.230	21 (15, 29)	21 (16, 30)	0.262	37 (26, 59)	34 (29, 47)	0.677
Polyp size (cm) [median (P25, P75)]	0.8 (0.5, 0.9)	0.8 (0.6, 0.9)	0.171	1.0 (0.8, 1.1)	1.0 (0.8, 1.1)	0.412	1.2 (0.8, 2.0)	1.1 (0.8, 1.5)	0.490
Polyp number [median (P25, P75)]	3.0 (1.0, 5.3)	4.0 (2.0, 6.0)	0.144	2.0 (1.0, 4.0)	2.0 (1.0, 4.0)	0.596	2.0 (1.0, 3.0)	2.0 (1.0, 4.0)	0.904
DPPB	2 (2.3)	4 (4.6)	0.688	31 (4.8)	37 (5.7)	0.431	2 (13.3)	0 (0.0)	0.176
Major bleeding	0 (0.0)	0 (0.0)	-	9 (1.4)	16 (2.5)	0.151	2 (13.3)	0 (0.0)	0.176
The timing of DPPB (day) [median (P25, P75)]	5.0 (4.0, 6.0)	1.5 (1.0, 11.0)	0.348	2.0 (1.0, 3.0)	2.0 (1.0, 3.0)	0.410	1.5 (1.0, 2.0)	-	-
The timing of major bleeding(day) [median (P25, P75)]	-	-	-	3.0 (1.5, 3.5)	2.0 (2.0, 3.8)	0.703	1.5 (1.0, 2.0)	-	-
Post-polypectomy perforation	0 (0.0)	1 (1.1)	1.000	0 (0.0)	1 (0.2)	0.498	0 (0.0)	0 (0.0)	-
Post-polypectomy hypoglycemia	1 (1.2)	0 (0.0)	0.497	2 (0.3)	10 (1.6)	0.019a	0 (0.0)	1 (5.0)	1.000
Post-polypectomy fever	1 (1.2)	5 (5.7)	0.218	14 (2.2)	15 (2.3)	0.831	1 (6.7)	2 (10.0)	1.000
post-polypectomy length of stay(day) [median (P25, P75)]	1.0 (1.0, 2.0)	2.0 (1.0, 2.0)	< 0.001b	1.0 (1.0, 2.0)	2.0 (1.0, 2.0)	< 0.001b	2.0 (1.0, 4.0)	2.0 (2.0, 2.0)	0.790

^aP < 0.05.

^bP < 0.01.

DPPB: Delayed post-polypectomy bleeding.

Table 7 Variable assignments

Independent variable	Assignment
Delayed post-polypectomy bleeding	“No” = 0, “yes” = 1
Major bleeding	“No” = 0, “yes” = 1
Age (year)	“≥ 50” = 0, “<50” = 1
Polyp number	Continuous variable
Polyp size	Continuous variable
Pedunculated polyp	“No” = 0, “yes” = 1
Polypectomy modality	Hybrid endoscopic submucosal dissection as a reference
Polyp location	Right colon as a reference
Early diet resumption following polypectomy	“No” = 0, “yes” = 1

Table 8 Multivariate analysis of risk factors for delayed post-polypectomy bleeding

Variable	B	SE	Wald	P value	OR	95%CI of OR value
						Lower	Upper
Age (< 50 years)	0.726	0.263	7.619	0.006b	2.067	1.234	3.461
Polyp number	0.076	0.035	4.823	0.028a	1.079	1.008	1.155
Polyp size (cm)	0.968	0.306	9.988	0.002b	2.633	1.444	4.800
Pedunculated polyp	0.190	0.276	0.476	0.490	1.209	0.705	2.075
Early diet resumption following polypectomy	-0.106	0.240	0.196	0.658	0.899	0.562	1.439

^aP < 0.05.

^bP < 0.01.

OR: Odds ratio.

Table 9 Multivariate analysis of risk factors for major bleeding

Variable	B	SE	Wald	P value	OR	95%CI of OR value
						Lower	Upper
Age (< 50 years)	1.038	0.419	6.133	0.013a	2.824	1.242	6.422
Hybrid endoscopic submucosal dissection			2.364	0.307
Cold forceps polypectomy and cold snare polypectomy	-18.239	2869.280	0.000	0.995	0.000	0.000
Hot snare polypectomy and endoscopic mucosal resection	-1.222	0.795	2.364	0.124	0.294	0.062	1.399
Right colon			6.738	0.034
Left colon	0.944	0.572	2.725	0.099	2.570	0.838	7.879
Transverse colon	-0.716	0.881	0.660	0.417	0.489	0.087	2.749
Polyp number	0.129	0.050	6.567	0.010a	1.138	1.031	1.256
Polyp size (cm)	0.718	0.480	2.243	0.134	2.051	0.801	5.250
Pedunculated polyp	0.333	0.454	0.540	0.462	1.396	0.574	3.395
Early diet resumption following polypectomy	-0.305	0.404	0.567	0.451	0.737	0.334	1.629

^aP < 0.05.

OR: Odds ratio.