Risk factors for colonoscopic perforation: A population-based study of 80118 cases

Table 1 Potential risk factors stratified by colonic perforation n (%)

	No perforation(n = 80068)	Perforation(n = 50)	P-value
Age category (yr)			< 0.0001
18-50	13698 (17.11)	5 (10.00)
50-65	38695 (48.33)	10 (20.00)
65-80	22954 (28.67)	20 (40.00)
80+	4271 (5.90)	15 (30.00)
Gender	n = 80059	n = 50	0.0183
Male	38972 (46.68)	16 (32.00)
Female	41087 (51.32)	34 (68.00)
BMI (median, IQR)	28.66 (25.14, 32.92)	26.27 (20.70, 28.55)	0.0002
(5.35% unknown)3	n = 79615	n = 48
Operator specialty4	n = 78421	n = 46	0.2290
Surgery	13826 (17.63)	5 (10.87)
Gastroenterology	64595 (82.37)	41 (89.13)
Type of colonoscopy2			< 0.0001
Therapeutic	37867 (47.29)	13 (26.53)
Polypectomy	16367 (20.44)	6 (12.42)
Dilation	97 (0.12)	2 (4.08)
Biopsy	18807 (23.49)	2 (4.08)
Other1	2596 (3.2)	3 (6.1)
Screening	29898 (37.34)	3 (6.12)
Diagnostic	12303 (15.37)	33 (67.35)
Number of Interventions performed5			0.0342
1	73919 (92.32)	45 (90.00)
2	5527 (6.90)	3 (6.00)
3	622 (0.78)	2 (4.00)
Count of morbidities			0.2004
0	55601 (69.4)	31 (62.0)
1	17330 (21.6)	11 (22.0)
2+	7137 (8.9)	8 (16.0)
Setting			< 0.0001
Inpatient	4132 (5.2)	23 (46.0)
Outpatient	75936 (94.8)	27 (54.0)
ICU	85 (0.1)	9 (18.0)	< 0.0001
Indications for CP
Abdominal pain	3623 (4.52)	7 (14.00)	0.0070
Anemia	1875 (2.34)	5 (10.00)	0.0063
Bleeding	3615 (4.51)	7 (14.00)	0.0070
Crohn’s disease	329 (0.41)	2 (4.00)	0.0183
Diarrhea	2565 (3.20)	0 (0)	0.4115
Diverticulosis of colon	15635 (19.53)	10 (20.00)	0.9328
Obstruction	416 (0.52)	0 (0)	0.9999
Ulcerative colitis	920 (1.15)	1 (2.00)	0.4391
Weight loss	464 (0.58)	1 (2.00)	0.2526
Creatinine (median, IQR) (12% unknown)	0.9 (0.7, 1.0)	0.9 (0.7, 1.1)	0.9824

¹Includes foreign body removal, hemostasis;

²Info to ascertain type of colonoscopy in one perforation not available;

³Two body mass index (BMI) in perforation group not available;

⁴Operator specialty of 4 perforations are other then gastroenterology and general surgery;

⁵Number of interventions includes biopsy, polypectomy ,dilations and hemostasis. ICU: Intensive care unit; CP: Cerebral palsy; IQR: Interquartile range.

Table 2 Incidence of 7-d colonic perforation risk by important risk factors

Patient variable	Frequ-ency	Perforat-ions	Incidence per 10000	Incident rate ratio (95%CI)
Total	80118	50	6.2	-
Age (yr)				1.071
				(1.05, 1.09)
18-49	13703	5	3.6
50-64	38705	10	2.6
65-79	22974	20	8.7
80+	4736	15	31.7
Gender
Female	41121	34	8.3	-
Male	38988	16	4.1	0.50 (0.27, 0.90)
BMI (kg/m2)				0.911 (0.86, 0.96)
< 24 (normal weight)	18019	21	11.7
25-29 (overweight)	26873	17	6.3
30+ (obese)	30873	10	3.2
Type of Colonoscopy
Therapeutic	37880	13	3.4	-
Screening	29901	3	1.0	0.29 (0.08, 1.03)
Diagnostic	12336	33	26.8	7.79 (4.10, 14.80)
Albumin result (percentile cut-offs)				0.151 (0.12, 0.20)
≤ 4.0	16537	36	21.8	7.76 (4.12, 14.64)
> 4.1	46366	13	2.8	-
ICU patients	94	9	957.4	186.9 (93.5, 373.5)
Non-ICU patients	80024	41	5.1	-
Inpatients	4155	23	55.4	15.6 (8.9, 27.1)
Outpatients	75963	27	3.6	-
Indications for CP
Abdominal pain				3.4 (1.5, ,7.6)-
Yes	3630	7	19.3
No	76488	43	5.6
Anemia				4.6 (1.8, 11.6)-
Yes	1880	5	26.6
No	78238	45	5.8
Bleeding				3.4(1.5, 7.6)-
Yes	3622	7	19.3
No	76496	43	5.6
Crohn’s disease
Yes	331	2	60.4	10.0
No	79787	48	6	(2.5, 41.2)

¹Variable was treated as continuous in the estimation of the incident rate ratio. ICU: Intensive care unit; CP: Cerebral palsy; BMI: Body mass index.

Table 3 Multivariate log-binomial regression results predicting 7-d post colonoscopic perforation

Risk factor	Model without albumin	Model with albumin
Age	1.04 (1.01, 1.06)	1.03 (1.01, 1.05)
BMI	0.96 (0.91, 1.00)	0.94 (0.90, 0.99)
ICU	9.37 (4.42, 19.88)	5.83 (2.80, 12.14)
Inpatient	18.08 (8.58, 38.17)	11.05 (5.14, 23.75)
Type of colonoscopy
Therapeutic	-	-
Screening	0.25 (0.07, 0.87)	0.17 (0.04, 0.76)
Diagnostic	12.93 (6.65, 25.13)	15.33 (7.79, 30.18)
Abdominal pain	5.32 (2.40, 11.82)	5.79 (2.64, 12.74)
Crohn’s disease	11.26 (3.88, 32.70)	5.16 (1.79, 14.88)
Albumin ( ≤ 4.0)	-	3.58 (1.72, 7.47)

BMI: Body mass index; ICU: Intensive care unit.