Table 1. Baseline characteristics of the study subjects and initial colonoscopy.
| N = 441 | |
|---|---|
| Age at initial colonoscopy (years), mean ± SD | 59.1 ± 11.0 |
| Male sex (%) | 305 (69.2) |
| BMI (Kg/m2), mean ± SD | 24.4 ± 3.1 |
| Smoking habit (%) | |
| No | 277 (62.8) |
| Ex-smoker | 74 (16.8) |
| Current | 90 (20.4) |
| Alcohol consumption (%) | |
| No | 225 (51.0) |
| Social | 181 (41.0) |
| Heavy | 35 (7.9) |
| Family history of colorectal cancer (%) | |
| No | 428 (97.1) |
| Yes | 13 (2.9) |
| History of colon polyp (%) | |
| No | 305 (69.2) |
| Yes | 136 (30.8) |
| History of abdomen surgery (%) | |
| No | 366 (83.0) |
| Low-riska | 36 (8.2) |
| High-riskb | 39 (8.8) |
| Comorbidity (%) | |
| Hypertension | 142 (32.2) |
| Diabetes mellitus | 80 (18.1) |
| Dyslipidemia | 40 (9.1) |
| Arterial thromboembolic diseasec | 21 (4.8) |
| Indication for colonoscopy (%) | |
| Screen or Surveillance | 362 (82.1) |
| Diagnostic purpose | 58 (13.2) |
| Bowel habit change | 21 (4.8) |
| Abdominal pain | 18 (4.1) |
| Hematochezia | 10 (2.3) |
| Iron deficiency anemia | 5 (1.1) |
| Positive stool occult blood | 3 (0.7) |
| Weight loss | 1 (0.2) |
| Therapeutic purpose | 21 (4.8) |
| Bowel preparation scale | |
| ABPS | 239 (54.2) |
| BBPS | 202 (45.8) |
| Bowel preparation material, n (%) | |
| 4L PEG | 320 (72.6) |
| Sodium picosulfate + magnesium oxide | 58 (13.2) |
| 2L PEG + ascorbic acid | 54 (12.2) |
| Othersd | 9 (2.0) |
| Bowel preparation method, n (%) | |
| Split | 246 (55.8) |
| Same day | 195 (44.2) |
| Out-patient, n (%) | |
| No | 84 (19.0) |
| Yes | 357 (81.0) |
| Endoscopists’ experience, n (%) | |
| Trainee | 197 (44.7) |
| Expert | 244 (55.4) |
| Withdrawal time, mean ± SD (min) | 15.7 ± 11.9 |
| Colonoscopy finding, n (%) | |
| No adenoma | 187 (42.4) |
| Low-risk adenomae | 142 (32.2) |
| High-risk adenomaf | 112 (25.4) |
| Interval, mean ± SD (months) | 14.1 ± 6.0 |
SD, standard deviation; BMI, Body mass index; ABPS, Aronchick bowel preparation scale; BBPS, Boston bowel preparation scale; PEG, polyethylene glycol.
aAbdominal surgery with low-risk of incomplete colonoscopic insertion included appendectomy, cholecystectomy, hernia repair.
bAbdominal surgery with high-risk of incomplete colonoscopic insertion included extensive abdominal operation, pelvic surgery, gynecologic surgery.
cArterial thromboembolic disease included ischemic heart disease or stroke.
dOthers included as following, 2L PEG ± bisacodyl, 3L PEG, 4L PEG + bisacodyl, 6L PEG, 8L PEG, 3L PEG + ascorbic acid, Macrogol solution + bisacodyl, sodium phosphate.
eLow-risk adenoma was defined 1 or 2 adenomas without advanced adenoma feature.
fHigh-risk adenoma included advanced adenoma or more than equal to 3 adenomas.