Trend of the polyp and adenoma detection rate by sex and age in asymptomatic average-risk and high-risk individuals undergoing screening colonoscopy, 2012-2019

Adenoma detection rate (ADR) is an imperative quality measure for colorectal cancer (CRC) screening. This retrospective observational study aimed to determine the trend of polyp detection rate (PDR) and ADR in asymptomatic average- and high-risk participants in different age groups who underwent screening colonoscopy over the seven years from April 2012 to March 2019 in a tertiary gastroenterology referral center of Iran. Of 1676 participants, 51.8 % were men (mean age 52.3 years). The overall PDR and ADR were 22.7 %, and 13.5 %, respectively. Both Polyps and adenomas were more common in age groups 51-59 and ≥60 years in high-risk patients than in the corresponding groups of average-risk patients (p < 0.05). Also, both PDR and ADR were more frequent in men than in women among all studied age groups, but it was statistically significant only for the youngest age group (16.8 % versus 10.5 %, p < 0.05) for PDR and the oldest age group (19.7 % versus 13 %, p < 0.05) for ADR, respectively. The trend of total ADR was upward over 7 years in both average-risk (6.7 % to 13.3 %) and high-risk (9.8 % to 27 %) groups and across all age groups in both sexes. Multivariable logistic regression revealed that high-risk individuals had an elevated risk of adenoma compared with average-risk patients (OR: 1.6, p = 0.006). Substantial variation in thresholds of polyp and adenoma detection by age, sex, and risk categories emphasizes the need for a risk-adapted approach to CRC screening and prevention programs.

Is There a Difference in Adenoma Detection Rates According to Indication? An Experience in a Panamanian Colorectal Cancer Screening Program

Background

The benefit of colorectal cancer screening in reducing cancer risk and related death is unclear. There are quality measure indicators and multiple factors that affect the performance of a successful colonoscopy. The main objective of our study was to identify if there is a difference in polyp detection rate (PDR) and adenoma detection rate (ADR) according to colonoscopy indication and which factors might be associated.

Methods

We conducted a retrospective review of all colonoscopies performed between January 2018 and January 2019, in a tertiary endoscopic center. All patients ≥ 50 years old scheduled for a nonurgent colonoscopy and screening colonoscopy were included. We stratified the total number of colonoscopies into two categories according to the indication: screening vs. non-screening, and then calculated PDR, ADR and serrated polyp detection rate (SDR). We also performed logistic regression model to identify factors associated with detecting polyps and adenomatous polyps.

Results

A total of 1,129 and 365 colonoscopies were performed in the non-screening and screening group, respectively. In comparison with the screening group, PDR and ADR were lower for the non-screening group (33% vs. 25%; P = 0.005 and 17% vs. 13%; P = 0.005). SDR was non-significantly lower in the non-screening group when compared with the screening group (11% vs. 9%; P = 0.53 and 22% vs. 13%; P = 0.007).

Conclusion

In conclusion, this observational study reported differences in PDR and ADR depending on screening and non-screening indication. These differences could be related to factors related to the endoscopist, time slot allotted for colonoscopy, population background, and external factors.

Impact of sedation type on adenoma detection rate by colonoscopy

BACKGROUND & AIMS

Endoscopic detection of polyps and adenomas decreases the incidence and mortality of colorectal cancer. The available data concerning the relationship between the sedation type and adenoma detection rate (ADR) or polyp detection rate (PDR) is inconclusive. The aim of our study was to evaluate the impact of conscious vs. deep (propofol) sedation on the ADR/PDR in diagnostic and screening colonoscopies.

METHODS

This was a retrospective cohort study. Patients aged 50-75 years old presenting for a first screening or diagnostic colonoscopy were included. Baseline demographic characteristics were collected, as well as PDR and ADR. Endoscopic withdrawal time and quality of bowel preparation rated in a binary fashion were also collected. Two multivariate logistic regression models were used to evaluate the independent predictors of endoscopic detection of polyps and adenomas.

RESULTS

574 patients met our inclusion criteria. Mean age was 59.26 ± 7.21 with 52.4% females and an average BMI of 28.08 ± 4.89. 374 patients (65.2%) underwent screening colonoscopies, and deep sedation was performed in 200 patients (34.8%). Only 4.7% had bad bowel preparation. PDR was 70% and ADR was 52%. On bivariate analysis, no significant difference was shown in PDR and ADR between conscious and deep sedation groups (0.70, 0.71; p = 0.712 and 0.50, 0.54; p = 0.394, respectively). On multivariate analysis for PDR, age and withdrawal time were independent predictors. For ADR, age, female sex, and withdrawal time were independent predictors. Sedation type and the indication did not reach statistical significance in both models.

CONCLUSION

The use of deep sedation didn't influence the ADR/PDR quality metrics in our mixed cohort of screening and diagnostic colonoscopies.

Impact of second forward-view examination on adenoma detection rate during unsedated colonoscopy: a randomized controlled trial

Objectives

Colorectal cancer on the right side of the colon has been suggested to be harder to detect by colonoscopy. The aim of this study was to evaluate whether a second forward-view examination of the right side of the colon could increase the adenoma detection rate (ADR) and/or polyp detection rate (PDR).

Methods

This was a single-centre randomized controlled trial. Patients undergoing colonoscopy were recruited and randomly assigned to the second forward-view examination (SFE) group, in which the right side of the colon was examined twice or the traditional colonoscopy (TC) group in which the colonoscopy was performed in a standard manner. The primary outcome was the ADR of right colon. The overall PDR and ADR, PDR of the right colon, per-adenoma miss rate of the right colon, and advanced lesion detection rate were also recorded and compared.

Results

A total of 392 patients were included in the study (SFE group 197 vs. TC group 195). The ADR and PDR of the right colon in the SFE group were significantly higher than those in the TC group (ADR 10.7% vs. 5.1%; P = 0.042); PDR 17.8% vs. 9.7%, P = 0.021). No significant difference was found in overall PDR/ADR, or advanced lesion detection rate between the two groups.

Conclusions

This prospective controlled study revealed that a second forward-view examination could modestly increase the ADR and PDR of the right colon during unsedated colonoscopies. This simple, safe and time-effective technique might be recommended for routine unsedated colonoscopy.

Trial registration: Clinical Trials.gov, NCT03619122. Registered on 7/8/2018.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-01783-9.

Longer Withdrawal Time Is More Important than Excellent Bowel Preparation in Colonoscopy of Adequate Bowel Preparation

BACKGROUND

Adequate bowel preparation is crucial for effective screening colonoscopy. However, it is unclear whether higher bowel preparation scores correspond to beneficial effects on the adenoma and polyp detection rate (ADR and PDR) in the adequate bowel preparation group.

AIMS

This study aimed to evaluate the effects of bowel preparation, according to the Boston Bowel Preparation Scale (BBPS), and colonoscopy withdrawal time (CWT) on ADR and PDR in the adequate bowel preparation group.

METHODS

Healthy examinees between 50 and 75 years old who underwent colonoscopy between September 2015 and August 2016 were included. BBPS scores, CWT, ADR, and PDR were reviewed retrospectively. Predictors of ADR and PDR were analyzed with a generalized linear mixed model.

RESULTS

A total of 5073 cases with adequate bowel preparation (BBPS ≥ 6) were analyzed. Examinees with good (BBPS = 6, 7) and excellent (BBPS = 8, 9) bowel preparation were 1898 (37.4%) and 3175 (62.6%), respectively. Both ADR and PDR were higher in the good bowel preparation group than in the excellent bowel preparation group (ADR 47.3% vs. 45.0%, P = 0.035; PDR 73.7% vs. 69.5%, P = 0.004, respectively). In the multivariate analysis, CWT, rather than BBPS, was significantly associated with both ADR (OR 1.04; 95% CI 1.02-1.06; P < 0.001) and PDR (OR 1.05; 95% CI 1.02-1.07; P = 0.002).

CONCLUSIONS

Both ADR and PDR were lower when bowel preparation was excellent rather than good. However, CWT, not BBPS, was significantly associated with ADR and PDR in the adequate bowel preparation group. Therefore, meticulous inspection is important for high-quality colonoscopy regardless of the BBPS score in examinees with adequate bowel preparation.

Impact of Moderate versus Deep Sedation and Trainee Participation on Adenoma Detection Rate-Analysis of a Veteran Population

BACKGROUND/AIMS

The adenoma detection rate (ADR) is used as a quality indicator for screening and surveillance colonoscopy. The study aimed to determine if moderate versus deep sedation affects the outcomes of the ADR and other quality metrics in the veteran population.

METHODS

A retrospective review of colonoscopies performed at Memphis Veterans Affairs Medical Center over a one-year period was conducted. A total of 900 colonoscopy reports were reviewed. After exclusion criteria, a total of 229 index, average-risk screening colonoscopies were identified. Data were collected to determine the impact of moderate (benzodiazepine plus opioids) versus deep (propofol) sedation on the ADR, polyp detection rate (PDR), and withdrawal time.

RESULTS

Among 229 screening colonoscopies, 103 (44.9%) used moderate sedation while 126 (55%) were done under deep sedation. The ADR and PDR were not significantly different between moderate versus deep sedation at 35.9% vs. 37.3% (p=0.82) and 58.2% vs. 48.4% (p=0.13), respectively. Similarly, there was no significant difference in withdrawal time between moderate and deep sedation (13.4 min vs. 14 min, p=0.56) during screening colonoscopies.

CONCLUSION

In veterans undergoing index, average-risk screening colonoscopies, the quality metrics of the ADR, PDR, and withdrawal time are not influenced by deep sedation compared with moderate sedation.

Colonoscopic techniques in polyp detection: An Egyptian study

INTRODUCTION AND AIMS

The polyp detection rate (PDR) is defined as the percentage of colonoscopies in which one or more polyps are detected, and has been shown to be highly correlated with the adenoma detection rate. The aim of the present study was to evaluate the PDR at the Endoscopy Unit of the Kasr Al-Ainy Hospital, Cairo University, Egypt, through the i-SCAN, Endocuff, and underwater colonoscopy techniques.

MATERIALS AND METHODS

The study was conducted on 100 Egyptian subjects over 50 years of age. Their polyp detection rate was measured through 4 different colonoscopic techniques. An equal number of patients were divided into 4 groups: i-SCAN, Endocuff, underwater colonoscopy, and controls. The control group was examined using standard white light colonoscopy. The colonoscopy evaluation included the type of agent utilized for bowel preparation, preparation grade, and colonoscopy withdrawal time.

RESULTS

The general PDR was 48%. The i-SCAN technique had the highest rate (56%), followed by the underwater (52%) and the Endocuff (48%) techniques.

CONCLUSION

The i-SCAN and underwater colonoscopy techniques produced higher PDR than the Endocuff-assisted and standard techniques, but with no statistical significance.

[Application value of sedation in colonoscopy]

Objective: To investigate the value of sedation in colonoscopy. Methods: A retrospective cohort study of colonoscopy procedures was performed in our institution. Inclusion criteria: (1) colonoscopy procedures were performed by well-trained gastrointestinal surgeons our institution; (2) medical records were complete and colonoscopy was documented properly by notes, videos, photographs, and traceable pathological reports. Those with incomplete records or performed in other institution were excluded. According to above criteria, clinical data of 49 057 cases of clinic and hospitalization receiving diagnostic or therapeutic colonoscopyat Department of Gastric and Colorectal Surgery, Daping Hospital from July 2007 to February 2017 were collected. Among them, there were 24 638 (50.2%) males and 24 419 females, with mean age of (50.6±14.1) (4 to 98) years. Based on the application of sedation during colonoscopy, patients were divided into the sedation group (39 412 cases, 80.3%) and the non-sedation group (9 645 cases, 19.7%). Clinical characteristics of two groups were compared. Results: The sedation rate increased from 45.6% (369/810) to 94.8% (917/967) from 2007 to 2017. As compared to non-sedation group, a higher proportion of females [51.0% (20 095/39 412) vs. 44.8% (4 324/9 645), χ(2)=117.422, P<0.001] and younger median age (50.0 years vs. 51.0 years, Z=-4.774, P<0.001) were found in the sedation group, whose differences were statistically significant. In all the 9645 cases in the non-sedation group, about 5.5% (534) of them terminated the examination because of unbearable discomfort, including 244 (4.6%) males and 290 (6.7%) females (χ(2)=20.522, P<0.001). Among all the screening population who were ≥50 years old, there was no significant difference in the polyp detection rate (PDR) between the sedation group and the non-sedation group [26.7% (4 737/17 753) vs. 27.4% (1 093/3 984), χ(2)=0.937, P=0.330]. The cecal intubation rate (CIR) in the sedation group was significantly higher than that in the non-sedation group [(85.2% (14 422/16 933) vs. 76.1% (2 803/3 682), χ(2)=180.032, P<0.001]. Five cases in the sedation group developed iatrogenic colonic perforation (ICP), with none in the non-sedation group. Conclusions: The application of sedation in colonoscopy is increasingly popular. Sedation can significantly improve CIR in colonoscopy, while it has no positive influence on PDR. Meanwhile, sedation increases the medical expense and may result in higher ICP rate.

Effect of dynamic position changes during colonoscope withdrawal: a meta-analysis of randomized controlled trials

BACKGROUND

Colonoscopies are considered to be the primary screening test and gold standard test for colorectal cancer. Position changes during colonoscope withdrawal are believed to be associated with an increased adenoma detection rate (ADR) and polyp detection rate (PDR). However, previous results conflicted, and this study aimed to elucidate the effectiveness of dynamic position changes during colonoscope withdrawal.

METHODS

The relevant publications were identified by searching the medical databases. The primary outcomes were the ADR and PDR, which were pooled and analyzed. The secondary outcome was the withdrawal time. The studies that supplied the ADR and PDR for different segments of the colon were separated into subgroup analyses.

RESULTS

Five randomized controlled trials were eligible for analysis. The total ADR was higher with dynamic position changes than with a static position (odds ratio, [OR] 1.34; 95% confidence interval [CI] 1.13-1.59; p < 0.001), with low evidence of between-study heterogeneity (I₂ = 0%). Although the total PDR was slightly higher with dynamic position changes than with a static position (OR 1.23; 95% CI 0.88-1.73), there difference was not statistically significant (p = 0.22). The withdrawal time was only increased by 0.47 min (95% CI - 0.11 to 1.06) with dynamic position changes, without statistical significance (p = 0.11). The subgroup analysis showed that the ADR and PDR for the transverse colon were higher with dynamic position changes, with pooled estimates of ADR (OR 1.72; 95% CI 1.02-2.88; p = 0.04) and PDR (OR 1.79; 95% CI 1.08-2.96; p = 0.02).

CONCLUSION

Dynamic position changes during colonoscope withdrawal increased the total ADR; however, no obvious increase was found in the total PDR. The withdrawal time was not significantly prolonged with dynamic position changes. Subgroup analysis showed that the ADR and PDR in the transverse colon were obviously improved with dynamic position changes.

Optimizing Screening Colonoscopy: Strategies and Alternatives

Screening colonoscopy is the most effective screening procedure for the prevention of colorectal cancer. The efficacy of colonoscopy is highly dependent on the overall quality of how this procedure is indicated, planned, prepared, and performed. The quality is directly linked to the number of polyps and/or adenomas detected or, in other words, to the number of polyps or adenomas missed during the procedure. The quality has a direct impact on the rate of interval carcinoma and on the range of how the incidence and occurrence of colorectal cancer is reduced. This review summarizes the current status on general measures and procedure improvements and standards as well as technical advances which have been suggested and established to improve the quality of polyp and adenoma detection rate. This includes selection and preparation of the patients, planning, methodological and technical performance of the procedure, and technical advances of the endoscope technology in order to improve screening results. It also covers new technologies with wide angle endoscopes (Ewave) and IT-based approaches using artificial intelligence to such as ai4GI for the polyp detection and image analysis.

An in vitro and clinical dose-finding study of antifoaming effects of simethicone during colonoscopy

Simethicone is an antifoaming agent frequently added to endoscopic rinse solutions but has recently been implicated as a risk factor for transmission of infections due to the formation of simethicone deposits within scope channels. Since the build-up of residue is likely dose-related, the smallest effective dose of simethicone should be used but there are no data available on the effective dose. Thus, we conducted a dose-finding study in an "in vitro bubble model" to determine the appropriate simethicone dose. Six 100-mL test tubes were filled with a 1% (v/v) solution of kitchen detergent (Fairy®, Procter & Gamble, London, England) in water for irrigation (Baxter®, Sydney, Australia). One test tube served as the control, while different doses of simethicone (Infacol®, Nice Pak, Melbourne, Australia) were added to the other five tubes (0.02, 0.2, 2.0, 20, and 200 mg/100 mL). Oxygen was streamed for 30 s into the test tubes at a rate of 2 L/min. After 10 s, photographs were taken and the visible bubbles were semi-quantitatively rated by independent assessors blinded to the dosing of simethicone. Simethicone at doses of 2 mg/100 mL had no appreciable antifoaming effect, whereas concentrations ≥ 20 mg/100 mL were sufficient to suppress bubble formation. This is substantially lower compared with frequently used doses of up to 200 mg/100 mL. Subsequently, we tested the lower simethicone dose with previously used higher doses, in 1475 and 1340 patients, respectively. We found it to have no impact on polyp detection with a rate of 56.7% (54.2-59.3% [95% CI]) at the lower dose and 56.5% (53.8-59.1% [95% CI]) at the higher dose.

The impact of colonoscopy indication on polyp detection rate

Background

Adenoma/polyp detection rates are considered to be among the most important quality indicators of colonoscopy and are key measures of a quality procedure. However, they are designed for use in the screening setting and are not amenable to other colonoscopy indications. Little is known about their significance in other colonoscopy indications. We aimed to evaluate the impact of the various indications on polyp detection rate (PDR).

Methods

This was a retrospective, single-center study. Electronic reports of index colonoscopy procedures with adequate bowel preparation over a 10-year period were reviewed. Patients were divided into 7 groups based on the study indication. PDR was determined for each group and was compared to that of a control group, the screening indication group. Adjustment was made for potential confounders such as age, sex, and procedural setting.

Results

A total of 13,054 patients were considered suitable for the study. PDR was greatest in the positive fecal occult blood test group, with a value of 33.1% (P<0.01). Overall, the remaining groups showed similar PDRs compared with screening (22.1% vs. 20.4%; P=0.15). This trend persisted in a multivariate analysis, which showed the odds ratio in the positive fecal occult blood test group to be significantly higher, with a value of 1.955 (1.759-2.172, P<0.001) compared with the screening group.

Conclusion

PDR was highest for the positive fecal occult blood test indication, but was not affected significantly by most indications. Further randomized studies are warranted to confirm these findings and help calculate recommended thresholds for "overall" PDR.

Influence of Simethicone Added to the Rinse Water during Colonoscopies on Polyp Detection Rates: Results of an Unintended Cohort Study

BACKGROUND AND AIMS

Simethicone is a common antifoaming agent that is added to endoscopic rinse solutions, but data regarding its effect on polyp detection rates is lacking. In this study, we report the effect of discontinuation of this practice on polyp detection rates.

METHODS

Procedure data of 4,254 consecutive colonoscopies were used. Patients underwent standard bowel preparation with polyethyleneglycol (Glycoprep®). Colonoscopies were performed utilising Olympus EVIS EXERA III, CV-190 equipment, while quality data (withdraw times, polyp detection rates, quality of bowel preparation) was assessed utilising an endoscopy reporting system (Provation®). Following an educational event that highlighted that simethicone may form deposits in the channels of endoscopes, the practice to add simethicone (InfacolR, Nice Pak) to the auxiliary channel water pump was abandoned, but endoscopists were not notified about this change. After 5 days and performing 75 colonoscopies, the change of practice was identified and addition of simethicone recommenced.

RESULTS

The discontinuation of simethicone use reduced the polyp detection rate from 55% (95% CI 53-56) to 45% (95% CI 34-56, 1-sided, p = 0.028); the polyp detection rate returned to the pre-intervention levels of 55% (95% CI 52-58) upon resumption of normal practice.

CONCLUSION

The addition of simethicone to the auxiliary water pump during colonoscopy results in a 10% increase in polyp detection rates.

Does Hyoscine improve polyp detection rate during colonoscopy? Systematic Review & meta-analysis of randomized clinical trials

BACKGROUND/OBJECTIVE

Published studies have shown conflicting results regarding the benefit of Hyoscine Butylbrmoide use during colonoscopy in polyp and adenoma detection rates. This meta-analysis was conducted with the aim to summarize all available evidence.

METHODS

A literature search was carried out using PubMed, Ovid MEDLINE and the Cochrane Library database from inception to December 2017. Studies that compared the use of Hyoscine Butylbrmoide compared to placebo during colonoscopy were included. Pooled odds ratio and 95% confidence interval were calculated using Mantel-Haenszel fixed-effects model when there was no heterogeneity identified.

RESULTS

Of the 423 retrieved studies, eight met the eligibility criteria and were included in the analysis. There was no significant difference between the groups in terms of polyp and adenoma detection rates.There was no significant difference between the Hyoscine and placebo groups in polyp detection rate (49.3% vs 48%, OR = 1.06, 95% CI: 0.90-1.23, P = 0.50). Adenoma detection rate was also not significantly different between the 2 groups 33.7% vs, 31%; OR = 1.13; 95%CI: 0.95-1.35; P = 0.16). No heterogeneity was observed (P = 0.65, I² = 0%).

CONCLUSION

This meta-analysis found no significant impact of Hyoscine on polyp and adenoma detection when used during colonoscopy.

Impact of Hyoscine Bromide Use on Polyp Detection Rate During Colonoscopy: A Systematic Review and Meta-Analysis

Background

Colorectal cancer (CRC) is a leading cause of death worldwide. Polyp detection rate (PDR) and adenoma detection rate (ADR) are key focus in endoscopic research for CRC screening and prevention. Use of anti-spasmodic agents during colonoscopy to help identify adenomas and polyps has remained a controversial topic. Hyoscine butyl bromide (HBB) is the most commonly used anti-spasmodic agent in patients undergoing colonoscopy. Some randomized controlled trials (RCTs) have questioned the clinical efficacy and safety of routine use of HBB for polyp and adenoma detection rates.

Methods

We conducted a systematic search in PubMed and MEDLINE from inception until February 10, 2018, for studies which compared HBB with placebo. We used RevMan version 5.3 for analysis. Procedural end-points were polyps, adenomas, and advanced adenoma detection rates, mean number of polyps detected and cecal intubation time.

Results

We included seven RCTs with 2,588 patients in our analysis. A total of 1,301 patients were randomized to HBB arm and 1,287 to the placebo arm. There was no significant difference in the primary outcome of polyp detection rate, 654 in HBB group vs. 616 in the placebo group, (odds ratio (OR) = 1.11, confidence interval (CI) = 0.93 - 1.34, P = 0.25). There was no difference in secondary outcomes of adenoma detection rate, 430 in HBB group vs. 396 in the placebo group, (OR = 1.06, CI = 0.89 - 1.26, P = 0.51), advanced adenoma detection rate, 92 in HBB vs. 95 in placebo group (OR = 0.95, CI = 0.70 - 1.30, P = 0.76), mean number of polyps detected (point estimate = 0.12, CI = 0.00 - 0.23, P = 0.05), adenomatous polyps (OR = 0.84, CI = 0.39 - 1.81, P = 0.65) and cecal intubation time (point estimate = 0.73, CI = -1.98 - 0.52, P = 0.25) between the two groups.

Conclusions

The use of HBB in patients undergoing colonoscopy does not appear to improve polyp or adenoma detection rates. It showed a non-significant trend of increased mean number of polyps detected with HBB.

Timed colonoscopy withdrawal, a mandatory quality measure in the era of national screening?

BACKGROUND

A minimum recommended withdrawal time for screening colonoscopy is recommended for by both the US Multi-Society Task Force on Colorectal Cancer and European Society of Gastrointestinal Endoscopy.

AIM

To characterize the relationship between endoscopists withdrawal time at colonoscopy and polyp detection in a symptomatic cohort of patients as compared to previously untimed withdrawal.

METHODS

Three experienced medical endoscopists prospectively performed 1079 colonoscopies during a 24-month period in an Irish hospital. Mean withdrawal time and individual polyp detection rate were noted.

RESULTS

Introduction of mandatory withdrawal time which was monitored and documented was associated with higher polyp detection rate (33 versus 21%, p < 0.005) as compared to previously untimed withdrawal.

CONCLUSION

Our findings support a monitored colonoscopy withdrawal time of at least 6 min, which correlates with higher colon polyp detection rates in a symptomatic cohort.

Colonoscopy procedural volume increases adenoma and polyp detection rates in gastroenterologytrainees

AIM

To investigate changes in polyp detection throughout fellowship training, and estimate colonoscopy volume required to achieve the adenoma detection rate (ADRs) and polyp detection rate (PDRs) of attending gastroenterologists.

METHODS

We reviewed colonoscopies from July 1, 2009 to June 30, 2014. Fellows’ procedural logs were used to retrieve colonoscopy procedural volumes, and these were treated as the time variable. Findings from screening colonoscopies were used to calculate colonoscopy outcomes for each fellow for the prior 50 colonoscopies at each time point. ADR and PDR were plotted against colonoscopy procedural volumes to produce individual longitudinal graphs. Repeated measures linear mixed effects models were used to study the change of ADR and PDR with increasing procedural volume.

RESULTS

During the study period, 12 fellows completed full three years of training and were included in the analysis. The average ADR and PDR were, respectively, 31.5% and 41.9% for all fellows, and 28.9% and 38.2% for attendings alone. There was a statistically significant increase in ADR with increasing procedural volume (1.8%/100 colonoscopies, P = 0.002). Similarly, PDR increased 2.8%/100 colonoscopies (P = 0.0001), while there was no significant change in advanced ADR (0.04%/100 colonoscopies, P = 0.92). The ADR increase was limited to the right side of the colon, while the PDR increased in both the right and left colon. The adenoma per colon and polyp per colon also increased throughout training. Fellows reached the attendings’ ADR and PDR after 265 and 292 colonoscopies, respectively.

CONCLUSION

We found that the ADR and PDR increase with increasing colonoscopy volume throughout fellowship. Our findings support recent recommendations of ≥ 275 colonoscopies for colonoscopy credentialing.

Can polyp detection rate be used prospectively as a marker of adenoma detection rate?

BACKGROUND

Adenoma detection rate (ADR) is a quality indicator for screening colonoscopy, but its calculation is time-consuming. Polyp detection rate (PDR) has been found to correlate with ADR; however, its use as a quality indicator has been criticized out of concern for endoscopists artificially inflating the PDR. We aim to evaluate whether active monitoring affects PDR.

METHODS

In March 2015, 14 endoscopists were made aware that their personal PDRs would be tracked monthly as a quality improvement project. Endoscopists received a report of their individual monthly and cumulative PDR, departmental averages, and a benchmark PDR. Following the intervention, data were collected for consecutive patients undergoing average risk screening colonoscopy for six months. PDR, ADR, and adenoma to polyp detection ratio quotient (APDRQ) were compared to a six-month pre-intervention period.

RESULTS

2203 patients were included in the study. There was no statistically significant difference in PDR when comparing pre- and post-intervention (44 vs. 45%, OR 1.04; 95% CI 0.77-1.36). No statistically significant difference in ADR was observed when comparing pre- and post-intervention (29 vs. 30%, OR 1.03; 95% CI 0.64-1.52). There was no statistically significant difference in APDRQ when comparing pre- and post-intervention (0.67 vs. 0.66, OR 0.99; 95% CI 0.69-1.33).

CONCLUSIONS

Monthly report cards did not result in a change in PDR or APDRQ. In some environments, PDR can be used as a surrogate marker of ADR, despite endoscopist awareness that PDR is being measured.

Association of trainee participation with adenoma and polyp detection rates

AIM

To investigate whether adenoma and polyp detection rates (ADR and PDR, respectively) in screening colonoscopies performed in the presence of fellows differ from those performed by attending physicians alone.

METHODS

We performed a retrospective review of all patients who underwent a screening colonoscopy at Grady Memorial Hospital between July 1, 2009 and June 30, 2015. Patients with a history of colon polyps or cancer and those with poor colon preparation or failed cecal intubation were excluded from the analysis. Associations of fellowship training level with the ADR and PDR relative to attendings alone were assessed using unconditional multivariable logistic regression. Models were adjusted for sex, age, race, and colon preparation quality.

RESULTS

A total of 7503 colonoscopies met the inclusion criteria and were included in the analysis. The mean age of the study patients was 58.2 years; 63.1% were women and 88.2% were African American. The ADR was higher in the fellow participation group overall compared to that in the attending group: 34.5% vs 30.7% (P = 0.001), and for third year fellows it was 35.4% vs 30.7% (aOR = 1.23, 95%CI: 1.09-1.39). The higher ADR in the fellow participation group was evident for both the right and left side of the colon. For the PDR the corresponding figures were 44.5% vs 40.1% (P = 0.0003) and 45.7% vs 40.1% (aOR = 1.25, 95%CI: 1.12-1.41). The ADR and PDR increased with increasing fellow training level (P for trend < 0.05).

CONCLUSION

There is a stepwise increase in ADR and PDR across the years of gastroenterology training. Fellow participation is associated with higher adenoma and polyp detection.

Cap-Assisted Colonoscopy Increases Detection of Advanced Adenomas and Polyps

BACKGROUND

Cap-assisted colonoscopy (CAC) has been reported to increase the adenoma detection rate (ADR) in Asian population. However, CAC trials in non-Asian population have had conflicting results. Studies in North America have shown an improvement in ADRs with the use of CAC, but it mainly included white and African American patients. Given the lack of prospective studies of CAC in Hispanics, we conducted this randomized controlled trial.

MATERIALS AND METHODS

This is a randomized controlled trial comparing CAC with standard colonoscopy (SC) in patients undergoing screening or surveillance colonoscopy. Our primary outcome was the ADR. Secondary outcomes were polyp detection rate, mean polyp and ADR, advanced ADR (AADR) and detection rates based on polyp morphology and location.

RESULTS

A total of 440 patients were included in the study (88.5% Hispanic). Cecal and terminal ileum intubation rates were similar in both groups (CAC: 97% and 86% versus SC: 99% and 81%, respectively). CAC did not improve ADR in comparison with SC (0.65 versus 0.52; P = 0.079); however, CAC had a higher AADR in comparison with SC (9.9% versus 4.6%; P = 0.049). CAC detected significantly more pedunculated polyps as compared with flat and sessile polyps (P = 0.011). Complication rates were similar in the CAC and SC groups (0.9% versus 0%).

CONCLUSIONS

In a predominantly Hispanic population, no difference was seen in the mean ADR with the use of CAC. However, CAC, when compared with SC, resulted in an increased AADR and mean polyp detection rate.

High-definition colonoscopy increases adenoma detection rate. Surg Endosc. 2017;31:78-84. [PMID: 27287897 DOI: 10.1007/s00464-016-4986-7]

BACKGROUND

The adenoma detection rate (ADR) is a quality indicator for colonoscopy. High-definition (HD) imaging has been reported to increase polyp detection rates.

OBJECTIVE

The primary objective of this study was to compare polyp detection rate (PDR) and adenoma detection rate (ADR) before and after the implementation of HD colonoscopy.

METHODS

A retrospective chart review was performed on patients aged 48-55 years old, who underwent first-time screening colonoscopy. The first group underwent standard-definition (SD) colonoscopy in the first 6 months of 2011. The second group underwent screening with HD colonoscopy during the first 6 months of 2012. We compared age, gender, PDR, ADR, and average sizes of adenomatous polyps between gastroenterologist and colorectal surgeon and among physicians themselves. Statistical analysis was performed with Fischer's exact test and Pearson Chi-square.

RESULTS

A total of 1268 patients were involved in the study (634 in each group). PDR (35.6 vs. 48.2 %, p < 0.001) and ADR (22.2 vs. 30.4 %, p = 0.02) were higher in the HD group. The average size of an adenomatous polyp was the same in the two groups (0.58 vs. 0.57, p = 0.69). However, this difference was not seen among colorectal surgeons PDR (35.7 vs. 37 %, p = 0.789), ADR (22.9 vs. 24.5 % p = 0.513), but clearly seen among gastroenterologist, PDR (35.6 vs. 53.1 % p < 0.001) and ADR (21.9 vs. 32.9 % p < 0.001). When polyps were categorized into size groups, there was no difference in ADR between the two timeframes (<5 mm in size (41.5 vs. 35.4 %), 5-10 mm (49.3 vs. 60.1 %) and >10 mm (9.2 vs. 4.5 %), p = 0.07). Polyps were most commonly seen in the sigmoid colon (26.1 vs. 24.7 %). There was no difference in the rate of synchronous polyp detection between modalities (25.6 vs. 29 %, p = 0.51). Withdrawal time was the same in both procedure (9.2 vs. 8.5 min, p = 0.10).

CONCLUSION

Screening colonoscopy with high-definition technology significantly improved both PDR and ADR. In addition, high-definition colonoscopy may be particularly useful and advantageous among less experienced endoscopists in various community settings. However, there needs to be application to specific patient populations in future studies to assess for any statistical differences between standard- and high-definition modalities to determine clinical utility.

Impact of endoscopy nurse involvement on polyp detection rates during colonoscopy

AIM: To investigate the impact of endoscopy nurse involvement during colonoscopy on the polyp detection rate (PDR) and adenoma detection rate (ADR).

METHODS: This was a single-center, prospective study. Patients involved were prospectively randomized to a routine colonoscopy group or an endoscopy nurse involvement group. The association of nurse involvement with PDR and ADR was evaluated.

RESULTS: A total of 1192 patients were included in the study. The PDR was significantly higher (33.19% vs 27.81%, P = 0.000) among colonoscopies that included an endoscopy nurse compared with those performed by only a physician, as was the left-sided and the right-sided adenomas detected (P = 0.017). There was no difference in ADR between the two groups (20.88% vs 20.55%, P = 0.889). Nurse participation was associated with a higher detection rate of small (< 5 mm) polyps (P = 0.006).

CONCLUSION: Endoscopy nurse involvement in colonoscopies significantly improves the overall PDR. Involvement of a well-trained nurse in screening colonoscopies may be an effective strategy to increase access.

Correlation between number of polyps detected per colonoscopy and polyp detection rate in average risk Chinese population of colorectal cancer

AIM: To assess the association between the number of polyps detected per colonoscopy (PPC) and polyp detection rate (PDR).

METHODS: A retrospective analysis was performed of the data for patients who underwent screening colonoscopy in the Digestive Endoscopic Center of Changhai Hospital between March 2010 and February 2013. PDR and PPC were calculated by gender, age and endoscopist. Linear regression analysis was applied to study the relationship between PDR and PPC.

RESULTS: A total of 1928 subjects received complete colonoscopies. There were significant linear correlations between PDR and PPC by age in both genders (men: r = 0.96, P = 0.0092; women: r = 0.97, P = 0.0059). There was also a significant linear correlation by endoscopist (r = 0.88, P < 0.05).

CONCLUSION: There is a significant correlation between PDR and PPC. PPC can act as a supplementary index to help distinguish endoscopists who have different colonoscopy skills.

Rate and reasons for colonoscopic cecal intubation failure in an average risk population of colorectal cancer

AIM: To get the knowledge regarding the rate of colonoscopic cecal intubation failure in an average risk population of colorectal cancer and analyze the reasons for failed intubation.

METHODS: A retrospective analysis was performed of the data for patients who underwent colonoscopy at Changhai Hospital from January 2008 to September 2010. Average risk patients were selected according to their indications and divided into either a successful intubation group or a failed intubation group according to whether cecal intubation was achieved. Total cecal intubation rate (CIR) was calculated. The t test and χ² test were used to compare age, gender composition, bowel preparation status and polyp detection rate (PDR) between the two groups.

RESULTS: A total of 10164 subjects received colonoscopy, of which 613 (6.0%) did not complete the colonic examination. Compared with the success group, the failure group had greater mean age, poorer bowel preparation and higher PDR (P < 0.05), although gender composition was similar. The main reasons for intubation failure was stricture due to occupying lesions, followed by poor bowel preparation. A total of 253 (41.27%) cases of infiltrative cancer were found in the failure group.

CONCLUSION: Advanced age, poor bowel preparation and suffering from infiltrative cancer are associated with failed cecal intubation. The detection rate of advanced colorectal cancer is high in the Chinese average risk populations.

Diagnostic yield of third eye retroscope on adenoma detection during colonoscopy: A systematic review and meta-analysis

AIM: To determine the diagnostic yield of the “third eye retroscope”, on adenoma detection rate during screening colonoscopy.

METHODS: The “third eye retroscope” when used with standard colonoscopy provides an additional retrograde view to visualize lesions on the proximal aspects of folds and flexures. We searched MEDLINE (PubMed and Ovid), SCOPUS (including MEDLINE and EMBASE databases), Cochrane Database of Systemic Reviews, Google Scholar, and CINAHL Plus databases to identify studies that evaluated diagnostic yield of “third eye retroscope” during screening colonoscopy. DerSimonian Laird random effects model was used to generate the overall effect for each outcome. We evaluated statistical heterogeneity among the studies by using the Cochran Q statistic and quantified by I² statistics.

RESULTS: Four distinct studies with a total of 920 patients, mean age 59.83 (95%CI: 56.77-62.83) years, were included in the review. The additional adenoma detection rate (AADR) defined as the number of additional adenomas identified due to “third eye retroscope” device in comparison to standard colonoscopy alone was 19.9% (95%CI: 7.3-43.9). AADR for right and left colon were 13.9% (95%CI: 9.4-20) and 10.7 (95%CI: 1.9-42), respectively. AADR for polyps ≥ 6 mm and ≥ 10 mm were 24.6% (95%CI: 16.6-34.9) and 24.2% (95%CI: 12.9-40.8), respectively. The additional polyp detection rate defined as the number of additional polyps identified due to “third eye retroscope” device in comparison to standard colonoscopy alone was 19.8% (95%CI: 7.9-41.8). There were no complications reported with use of “third eye retroscope” device.

CONCLUSION: The “third eye retroscope” device when used with standard colonoscopy is safe and detects 19.9% additional adenomas, compared to standard colonoscopy alone.

Does metformin affect the incidence of colonic polyps and adenomas in patients with type 2 diabetes mellitus?

Background/Aims

Colorectal cancer (CRC) develops from colonic adenomas. Type 2 diabetes mellitus (DM) is associated with a higher risk of CRC and metformin decreases CRC risk. However, it is not certain if metformin affects the development of colorectal polyps and adenomas. This study aimed to elucidate if metforminaffects the incidence of colonic polyps and adenomas in patients with type 2 DM.

Methods

Of 12,186 patients with type 2 DM, 3,775 underwent colonoscopy between May 2001 and March 2013. This study enrolled 3,105 of these patients, and divided them in two groups: 912 patients with metformin use and 2,193 patients without metformin use. Patient clinical characteristics, polyp and adenoma detection rate in the two groups were analyzed retrospectively.

Results

The Colorectal polyp detection rate was lower in the metformin group than in the non-meformin group (39.4% vs. 62.4%, P<0.01). Colorectal adenoma detection rate was significantly lower in the metformin group than in the non-metformin group (15.2% vs. 20.5%, P<0.01). Fewer advanced adenomas were detected in the metformin group than in the non-metformin group (12.2% vs. 22%, P<0.01). Multivariate analysis identified age, sex, Body mass index and metformin use as factors associated with polyp incidence, whereas only metforminwas independently associated with decreased adenoma incidence (Odd ratio=0.738, 95% CI=0.554-0.983, P=0.03).

Conclusions

In patients with type 2 DM, metformin reduced the incidence of adenomas that may transform into CRC. Therefore, metformin may be useful for the prevention of CRC in patients with type 2 DM.

Cap-assisted colonoscopy

Cap-assisted colonoscopy is a simple, practical, and inexpensive technique that serves several useful purposes in enhancing the performance of colonoscopy. It helps improve polyp detection by its ability to visualize otherwise blind mucosal areas on the proximal aspects of folds and flexures, although its effect on adenoma detection is inconsistent. By helping navigate the colon more efficiently, it facilitates intubation of the cecum faster, with lesser patient discomfort. Cap-assisted colonoscopy can be tried as a salvage procedure in cases of failed cecal intubation with regular colonoscopy and can be of assistance during polypectomy, especially for polyps located on the proximal aspects of folds.

Endoscopy Nurse Participation May Increase the Polyp Detection Rate by Second-Year Fellows during Screening Colonoscopies

Background/Aims

The aim of this study was to assess the effects of endoscopy nurse participation on polyp detection rate (PDR) and adenoma detection rate (ADR) of second-year fellows during screening colonoscopies.

Methods

This was a single-center, prospective, randomized study comparing a fellow alone and a fellow plus an endoscopy nurse as an additional observer during afternoon outpatient screening colonoscopies. The primary end points were PDR and ADR.

Results

One hundred ninety-one colonoscopies performed by a fellow alone and 192 colonoscopies performed by a fellow plus an endoscopy nurse were analyzed. The PDR was significantly higher when the nurse was involved (53.1% vs. 41.3%, p<0.05); however, there was no significant difference in the ADR between the two groups (38.5% vs. 29.8%, p=0.073). There was no difference in the percentage of patients with ≥2 polyps, advanced adenomas, polyp size, polyp location, and polyp shapes between the two groups. There was no difference in the PDR according to the level of experience of the endoscopy nurse.

Conclusions

Endoscopy nurse participation as an additional observer during screening colonoscopy performed by second-year fellow increases the PDR; however, the level of experience of the nurse was not an important factor.