Adverse events related to colonoscopy: Global trends and future challenges

Table 1 Summary of calculated incidence rates for perforations related to colonoscopy from recent studies with sample sizes > 50,000 cases n (%)

Ref.	Duration of enrollment	Study design (data source)	Publication year	Country	Colonoscopies performed	Perforation rate (%)
Sieg et al[27]	1998-1999	Prospective study	2001	Germany	82416	4 (0.005)
Iqbal et al[76]	1994-2000	Retrospective study	2005	United States	78702	72 (0.084)
Rabeneck et al[77]	2002-2003	Population-based cohort study	2008	Canada	97091	54 (0.056)
Iqbal et al[13]	1980-2006	Retrospective review	2008	United States	258248	180 (0.070)
Bokemeyer et al[45]	2003-2006	Study based on German online registry	2009	Germany	269144	55 (0.020)
Crispin et al[45]	2006	Study based on compulsory health insurance (CHI)	2009	Germany	236087	69 (0.029)
Warren et al[47]	2001-2005	Population-based, matched cohort study.	2009	United States	53220	33 (0.062)
Arora et al[72]	1995-2005	Population-based cohort study	2009	United States	277434	228 (0.082)
Rabeneck et al[78]	2002-2003	Population-based cohort study	2011	Canada	67632	37 (0.055)
Pox et al[30]	2003-2008	Prospective cross-sectional study	2012	Germany	2821392	439 (0.016)
Hamdani et al[73]	2002-2010	Retrospective cross-sectional study	2013	United States	80118	50 (0.062)
Samalavicius et al[79]	2007-2011	Retrospective multicenter study	2013	Lithuania	56882	40 (0.070)
Blotière et al[29]	2010	Study based on comprehensive French health insurance data (SNIIRAM)	2014	France	947061	424 (0.045)
Rutter et al[52]	2006-2012	Study based on English National Health Service Bowel Cancer Screening Program (NHSBCSP)	2014	United Kingdom	130831	20 (0.015)
Zafar et al[48]	2007-2008	Health Insurance Portability and Accountability Act compliant study	2014	United States	54039	46 (0.085)
Bielawska et al[16]	2000-2011	Prospectively collected data from the Clinical Outcomes Research Initiative (CORI) National Endoscopic Database	2014	Canada	1144900	192 (0.017)
Shi et al[34]	2000-2012	Retrospective study	2014	China	110785	14 (0.012)

Table 2 Summary of related risk factors for post-polypectomy bleeding[36,41,51,80-84]

Patient-related factors	Polyp-related factors	Procedure-related factors
Old age	Polyp size	Cutting mode
Anticoagulants	Morphology of polyps	Bowel preparation
Cardiovascular disease	Histology	Inadvertent cold polypectomy
Chronic vascular disease	Number of resected polyps	Endoscopist’s experience
Clopidogrel and concomitant aspirin/nonsteroidal anti-inflammatory drugs		Resection method Use of prophylactic hemostasis

Table 3 Summary of calculated incidence rates for bleeding related to colonoscopy from recent studies with sample sizes > 50,000 cases n (%)

Ref.	Duration of enrollment	Study design (data source)	Publication year	Country	Colonoscopies performed	Bleeding
Sieg et al[27]	1998-1999	Prospective study	2001	Germany	82416	1 (0.001)
Rabeneck et al[77]	2002-2003	Population-based cohort study	2008	Canada	97091	137 (0.141)
Bokemeyer et al[45]	2003-2006	Study based on German online registry	2009	Germany	269144	442 (0.164)
Crispin et al[46]	2006	Study based on compulsory health insurance (CHI)	2009	Germany	236087	520 (0.220)
Warren et al[47]	2001-2005	Population-based, matched cohort study	2009	United States	53220	340 (0.639)
Rabeneck et al[78]	2002-2003	Population-based cohort study	2011	Canada	67632	83 (0.123)
Pox et al[30]	2003-2008	Prospective cross-sectional study	2012	Germany	2821392	573 (0.020)
Blotière et al[29]	2010	Study based on comprehensive French health insurance data (SNIIRAM)	2014	France	947061	933 (0.099)
Rutter et al[52]	2006-2012	Study based on English National Health Service Bowel Cancer Screening Program (NHSBCSP)	2014	United Kingdom	130831	291 (0.222)
Zafar et al[48]	2007-2008	Health Insurance Portability and Accountability Act compliant study	2014	United States	54039	371 (0.687)

Table 4 Perforation rates per colonoscopy indication and procedure type from recent studies with sample sizes > 50,000 cases (%)

Ref.	Indication		Procedure
	Screening/surveillance	Symptomatic/diagnostic	Without polypectomy	With polypectomy
Sieg et al[27]	-	-	0.005	0.063
Crispin et al[46]	0.040	0.030	-	-
Warren et al[47]	0.056	0.050	0.052	0.070
Arora et al[72]	0.067	0.086	0.077	0.077
Pox et al[30]	0.016	-	0.012	0.046
Hamdani et al[73]	0.010	0.268	0.010	0.037
Rutter et al[52]	0.063	-	0.031	0.091
Bielawska et al[16]	0.011	0.022	-	-

Table 5 Bleeding rates per colonoscopy indication and procedure type from recent studies with sample sizes > 50,000 cases (%)

Ref.	Indication		Procedure
	Screening/surveillance	Symptomatic/diagnostic	Without polypectomy	With polypectomy
Sieg et al[27]	-	-	0.001	0.270
Crispin et al[46]	0.240	0.210	-	-
Warren et al[47]	0.206	0.375	0.336	0.874
Pox et al[30]	0.020	-	0.001	0.092
Rutter et al[52]	0.647	-	0.102	1.136

Table 6 Summary of major risk factors for perforation and bleeding related to colonoscopy from recent studies with sample sizes > 50,000 cases (%)

Ref.	Risk factors for perforation	Risk factors for bleeding
Rabeneck et al[77]	Comorbidity score ≥ 3 (OR: 3.73, 95%CI: 1.59-8.77), Polypectomy (OR: 2.96, 95%CI: 2.31-3.80), Old age (OR: 2.06, 95%CI: 1.79-2.37)	Polypectomy (OR: 10.32, 95%CI: 6.52-16.34), Old age (OR: 1.61, 95%CI: 1.20-2.16)
Crispin et al[46]	Polyp size: 0.5-1 cm (OR: 11.93, 95%CI: 3.02-47.13), Polyp size: 1-3 cm (OR: 28.12, 95%CI: 7.82-101.09), Polyp size > 3 cm (OR: 31.49, 95%CI: 6.37-155.66), Polypectomy (OR: 2.27, 95%CI: 1.39-3.70), Old age (OR: 1.00, 95%CI: 1.00-1.00)	Polyp size: 0.5-1 cm (OR: 5.25, 95%CI: 3.42-8.06), Polyp size: 1-3 cm (OR: 16.84, 95%CI: 11.14-25.46), Polyp size > 3 cm (OR: 27.52, 95%CI: 17.20-44.05), Polypectomy (OR: 60.21, 95%CI: 35.90-100.99), Biopsy (OR: 8.88, 95%CI: 5.06-15.59), Colonoscopy in patients with symptoms (OR: 1.31, 95%CI: 1.04-1.67), Pedunculated polyp (OR: 1.55, 95%CI: 1.26-1.90), Number of polyps: 2-4 (OR: 1.26, 95%CI: 1.06-1.50), Old age (OR: 1.00, 95%CI: 1.00-1.00)
Arora et al[72]	Colonoscopy indication (obstruction) (OR: 5.09, 95%CI: 3.17-8.20), Colonoscopy procedure1 (OR: 6.12, 95%CI: 3.16-11.83), Comorbidity score ≥ 2 (OR: 1.52, 95%CI: 1.12-2.06), Old age (OR: 1.01, 95%CI: 1.00-1.02)	-
Pox et al[30]	Polypectomy	Polypectomy
Hamdani et al[73]	Colonoscopy indication: Crohn’s disease (OR: 5.16, 95%CI: 1.79-14.88), Colonoscopy indication: abdominal pain (OR: 5.79, 95%CI: 2.64-12.74), Colonoscopy indication : Diagnostic (OR: 15.33, 95%CI: 7.79-30.18), Inpatient (OR: 11.05, 95%CI: 5.14-23.75), ICU patient (OR: 5.83, 95%CI: 2.80-12.14), Low albumin (≤ 4.0) (OR: 3.58, 95%CI: 1.72-7.47), Old age (OR: 1.03, 95%CI: 1.01-1.05)	-
Samalavicius et al[79]	Low-volume practice center	-
Blotière et al[29]	Age: 60-69 (OR: 2.91, 95%CI: 1.66-5.10), Age: 70-79 (OR: 5.38, 95%CI: 3.08-9.40), Age ≥ 80 (OR: 7.51, 95%CI: 4.20-13.45), Emergency colonoscopy (OR: 4.63, 95%CI: 3.52-6.10), Polyp size ≥ 1 cm (OR: 2.72, 95%CI: 2.05-3.60)	Age: 60-69 (OR: 1.70, 95%CI: 1.18-2.43), Age: 70-79 (OR: 2.55, 95%CI: 1.77-3.66), Age ≥ 80 (OR: 3.23, 95%CI: 2.21-4.73), Emergency colonoscopy (OR: 5.99, 95%CI: 5.01-7.15), Polyp size ≥ 1 cm (OR: 5.12, 95%CI: 4.33-6.04), Chronic disease (OR: 1.76, 95%CI: 1.53-2.02), Gender (male) (OR: 1.64, 95%CI: 1.43-1.87)
Rutter et al[52]	Polypectomy, Location of polyp (cecum) (OR: 5.60, 95%CI: 1.37-22.83)	Polypectomy, Location of polyp (cecum) (OR: 13.50, 95%CI: 3.93-46.42), Increasing polyp size (OR: 4.92, 95%CI: 2.84-8.51)
Bielawska et al[16]	Age: 60-74 (OR: 2.69, 95%CI: 1.83–3.98), Age ≥ 75 (OR: 5.63, 95%CI: 3.73-8.49), Gender (female) (OR: 2.00, 95%CI: 1.43-2.80), ASA class III (OR: 2.14, 95%CI: 1.22-3.75), ASA class IV/V (OR: 7.20, 95%CI: 2.41-21.50), Hospital setting: university (OR: 2.83, 95%CI: 1.85-4.31), Hospital setting: VA/military (OR: 3.74, 95%CI: 2.37-5.89), Any therapy (OR: 3.93, 95%CI: 2.05-7.56), Polyp size ≥ 1 cm (OR: 4.14, 95%CI: 2.58-6.65), Endoscopy specialty: surgery or unknown (OR: 2.00, 95%CI: 1.30-3.08)	-

¹Colonoscopy procedure includes treatment of foreign-body, submucosal injection, hemostasis, endoscopic ultrasound, transmural or intramural aspiration or biopsy.