Abstract
Background
Adenoma detection and removal is crucial to prevent colon cancer. Although adenoma detection rate is the current benchmark, there is increasing interest in sessile serrated adenoma detection rate (SSADR) given sessile serrated adenomas (SSAs) are more difficult to identify endoscopically.
Aims
To define predictors of SSA detection in a large colonoscopy cohort.
Methods
We performed a prospective observational study using colonoscopy quality metrics collected by Cancer Care Ontario. All colonoscopies performed for any indication across 20 hospitals in Southwestern Ontario between April 2017 and February 2018 were identified. Data collected included patient demographics, procedural indication, bowel preparation, cecal intubation, endoscopist information, and histology of polyps removed. Cases without histology records were excluded. A multi-variable analysis was conducted to identify factors associated with SSA detection.
Results
In total, 17,524 colonoscopies (mean (SD) age = 59.6 (14.4), 53.9% female) were identified. At least one SSA was identified in 910 procedures, corresponding to a SSADR of 5.2%. On multi-variable analysis, variables independently associated with higher SSADR included increasing patient age (OR 1.02, 95% CI 1.02–1.03, p<0.001), cecal intubation (OR 3.80, 95% CI 1.87–7.71, p<0.001), use of split dose bowel preparation (OR 1.33, 95% CI 1.00–1.77, p=0.047), and very good bowel preparation quality (OR 2.48, 95% CI 1.38–4.44, p=0.002). Factors associated with lower SSADRs included non-screening colonoscopies (OR 0.55, 95% CI 0.48–0.63, p<0.001) and non-gastroenterologist endoscopist (general surgery OR 0.50, 95% CI 0.41–0.60, p<0.001; internal medicine OR 0.70, 95% CI 0.51–0.96, p=0.027; general practice OR 0.20, 95% CI 0.06–0.68, p=0.010).
Conclusions
Modifiable factors associated with higher SSADRs include use of split dose bowel preparation, better bowel preparation quality, cecal intubation, and specialty of endoscopist. Ongoing initiatives emphasizing the importance of these variables should be encouraged.
Clinical Predictors for SSA Detection
| Total (n=17,524) | Presence of SSA (n=910) | Absence of SSA (n=16,614) | p-value | |
|---|---|---|---|---|
| Age-mean (SD) | 59.6 (14.4) | 63.4 (11.8) | 59.4 (14.5) | <0.0001 |
| Sex-no. (%) | ||||
| Female | 9,451 (53.9%) | 493 (5.2%) | 8,958 (94.8%) | 0.882 |
| Male | 8,071 (46.1%) | 417 (5.2%) | 7,654 (94.8%) | |
| ASA grade-no. (%) | ||||
| 1 | 5,168 (29.5%) | 241 (4.7%) | 4,927 (95.3%) | 0.833 |
| 2 | 8,559 (48.8%) | 507 (5.9%) | 8,052 (94.1%) | |
| 3 | 3,540 (20.2%) | 151 (4.3%) | 3,389 (95.7%) | |
| 4 | 252 (1.4%) | 11 (4.4%) | 241 (95.6%) | |
| 5 | 4 (0.02%) | 0 (0%) | 4 (100%) | |
| Indication-no. (%) | <0.001 | |||
| Screening/Surveillance | 7,265 (41.5%) | 487 (6.7%) | 6,778 (93.3%) | |
| FOBT+ | 732 (4.2%) | 48 (6.6%) | 684 (93.4%) | |
| Symptomatic | 9,526 (54.4%) | 375 (3.9%) | 9,151 (96.1%) | |
| Admission status-no. (%) | 0.074 | |||
| Outpatient | 16,826 (96.0%) | 884 (5.3%) | 15,942 (94.7%) | |
| Inpatient | 698 (4.0%) | 26 (3.7%) | 672 (96.3%) | |
| Bowel prep timing-no. (%) | 0.001 | |||
| Split dose | 15,683 (90.0%) | 844 (5.4%) | 14,839 (94.6%) | |
| Non-split dose | 1,746 (10.0%) | 60 (3.4%) | 1,686 (96.6%) | |
| Complete colonoscopy-no. (%) | <0.001 | |||
| Cecal intubation | 16,627 (96.3%) | 896 (5.4%) | 15,731 (94.6%) | |
| No cecal intubation | 635 (3.7%) | 8 (1.3%) | 627 (98.7%) | |
| Bowel prep quality-no. (%) | <0.001 | |||
| Very good | 14,161 (80.9%) | 773 (5.5%) | 13,388 (94.5%) | |
| Fair | 2,734 (15.6%) | 125 (4.6%) | 2,609 (95.4%) | |
| Poor | 621 (3.6%) | 12 (1.9%) | 609 (98.1%) | |
| Specialty | <0.001 | |||
| GI | 7,739 (44.2%) | 527 (6.8%) | 7,212 (93.2%) | |
| General surgery | 8,350 (47.7%) | 315 (3.8%) | 8,035 (96.2%) | |
| Internal medicine | 1,200 (6.9%) | 65 (5.4%) | 1,135 (94.6%) | |
| General practice | 230 (1.3%) | 3 (1.3%) | 227 (98.7%) | |
| Length of practice-median (IQR) | 13 (6,27) | 15 (6,20) | 13 (6,27) | 0.021 |
| Procedure site-no. (%) | <0.001 | |||
| Academic centre | 10,214 (58.3%) | 637 (6.2%) | 9,577 (93.8%) | |
| Non-academic centre | 7,310 (41.7%) | 273 (3.7%) | 7,037 (96.3%) | |
| Trainee involvement-no. (%) | 0.202 | |||
| Present | 3,507 (20.1%) | 168 (4.8%) | 3,339 (95.2%) | |
| Absent | 13,910 (79.9%) | 741 (5.3%) | 13,169 (94.7%) |
Funding Agencies
None