Incidence, risk and protective factors of symptoms after colonoscopy.

BACKGROUND: Few studies focused on minor adverse events which may develop after colonoscopy. AIMS: To investigate the incidence and factors associated to post-colonoscopy symptoms. METHODS: This is a prospective study conducted in 10 Italian hospitals. The main outcome was a cumulative score combining 10 gastrointestinal (GI) symptoms occurring the week following colonoscopy. The analyses were conducted via multivariate logistic regression. RESULTS: Of 793 subjects included in the analysis, 361 (45.5%) complained the new onset of at least one GI symptom after the exam; one symptom was reported by 202 (25.5%), two or more symptoms by 159 (20.1%). Newly developed symptoms more frequently reported were epigastric/abdominal bloating (32.2%), pain (17.3%), and dyspeptic symptoms (17.9%). Symptoms were associated with female sex (odds ratio [OR]=2.54), increasing number of symptoms developed during bowel preparation intake (OR=1.35) and somatic symptoms (OR=1.27). An inverse association was observed with better mood (OR=0.74). A high-risk profile was identified, represented by women with bad mood and somatic symptoms (OR=8.81). CONCLUSION: About half of the patients develop de novo GI symptoms following colonoscopy. Improving bowel preparation tolerability may reduce the incidence of post-colonoscopy symptoms, especially in more vulnerable patients.

Determinants of symptom burden related to bowel preparation for colonoscopy.

BACKGROUND: Symptoms developing during bowel preparation are major concerns among subjects who refuse the procedure. AIMS: We aimed to explore the determinants of symptoms occurring during preparation among patients undergoing elective colonoscopy. METHODS: This is a prospective multicenter study conducted in 10 Italian hospitals. A multidimensional approach collecting socio-demographic, clinical, psychological and occupational information before colonoscopy through validated instruments was used. Outcome was a four-category cumulative score based on symptoms occurring during preparation, according to the Mayo Clinic Bowel Prep Tolerability Questionnaire, weighted by intensity. Missing values were addressed through multiple imputation. Odds ratios (OR) and 95% confidence intervals (CI) were estimated through multivariate logistic regression models. RESULTS: 1137 subjects were enrolled. Severe symptoms were associated with female sex (OR=3.64, 95%CI 1.94-6.83), heavier working hours (OR=1.13, 95% CI=1.01-1.25), previous gastrointestinal symptoms (OR=7.81, 95% CI 2.36-25.8 for high score), somatic symptoms (OR=2.19, 95% CI=1.06-4.49 for multiple symptoms), day-before regimen (OR=2.71, 95%CI 1.28-5.73). On the other hand, age ≥60 years (OR=0.10, 95% CI 0.02-0.44) and good mood (p=0.042) were protective factors. A high-risk profile was identified, including women with low mood and somatic symptoms (OR=15.5, 95%CI 4.56-52.7). CONCLUSIONS: We identified previously unreported determinants of symptoms burdening bowel preparation and identified a particularly vulnerable phenotype. Symptoms during preparation especially impact heavier working activity.

Impact of colonoscopy on working productivity: a prospective multicenter observational study.

BACKGROUND AND AIMS: Patients undergoing colonoscopy are often in the workforce. Therefore, colonoscopy may affect patients' work productivity in terms of missed working days and/or reduced working efficiency. We aimed to investigate the impact of colonoscopy on work productivity and factors influencing this impact. METHODS: We conducted a prospective, observational, multicenter study in 10 Italian hospitals between 2016 and 2017. We collected information on individual characteristics, work productivity, symptoms, and conditions before, during, and after the procedure from patients undergoing colonoscopy for several indications using validated tools. Outcomes were interference of preparation with work, absenteeism, and impaired work performance after the procedure. We fitted multivariate logistic regression models to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for potential predictors of the outcomes. RESULTS: Among 1137 subjects in the study, 30.5% reported at least 1 outcome. Impaired work performance was associated with bowel preparation regimen (full dose on the day of colonoscopy vs split dose: OR, 4.04; 95% CI, 1.43-11.5), symptoms during bowel preparation (high symptom score: OR, 3.21; 95% CI, 1.15-8.95), and pain during the procedure (OR, 2.47; 95% CI, 1.40-4.35). Increasing number of working hours and less comfortable jobs were associated with absenteeism (P for trend = .06) and impairment of working performance (P for trend = .01) and GI symptoms both before and after colonoscopy. CONCLUSIONS: Occupational and individual characteristics of patients should be considered when scheduling colonoscopy because this procedure may impair work productivity in up to one-third of patients. Split-dose bowel preparation, performing a painless colonoscopy, and preventing the occurrence of GI symptoms may minimize the impact of colonoscopy on work productivity.

Water Exchange Produces Significantly Higher Adenoma Detection Rate Than Water Immersion: Pooled Data From 2 Multisite Randomized Controlled Trials.

GOALS: To test the hypothesis that water exchange (WE) significantly increases adenoma detection rates (ADR) compared with water immersion (WI). BACKGROUND: Low ADR was linked to increased risk for interval colorectal cancers and related deaths. Two recent randomized controlled trials of head-to-head comparison of WE, WI, and traditional air insufflation (AI) each showed that WE achieved significantly higher ADR than AI, but not WI. The data were pooled from these 2 studies to test the above hypothesis. STUDY: Two trials (5 sites, 14 colonoscopists) that randomized 1875 patients 1:1:1 to AI, WI, or WE were pooled and analyzed with ADR as the primary outcome. RESULTS: The ADR of AI (39.5%) and WI (42.4%) were comparable, significantly lower than that of WE (49.6%) (vs. AI P=0.001; vs. WI P=0.033). WE insertion time was 3 minutes longer than that of AI (P<0.001). WE showed significantly higher detection rate (vs. AI) of the >10 mm advanced adenomas. Right colon combined advanced and sessile serrated ADR of AI (3.4%) and WI (5%) were comparable and were significantly lower than that of WE (8.5%) (vs. AI P<0.001; vs. WI P=0.039). CONCLUSIONS: Compared with AI and WI, the superior ADR of WE offsets the drawback of a significantly longer insertion time. For quality improvement focused on increasing adenoma detection, WE is preferred over WI. The hypothesis that WE could lower the risk of interval colorectal cancers and related deaths should be tested.

Underwater endoscopic colorectal polyp resection: Feasibility in everyday clinical practice.

BACKGROUND: Endoscopic mucosal resection is well-established for resecting flat or sessile benign colon polyps. The novel underwater endoscopic mucosal resection eschews submucosal injection prior to endoscopic mucosal resection. Reports about underwater endoscopic mucosal resection were limited to small series of single and/or tertiary-care referral centers, with single or supervised operators. OBJECTIVE: The purpose of this study was to determine feasibility and efficacy of underwater resection of polyps of any morphology (underwater polypectomy, here includes underwater endoscopic mucosal resection) in routine clinical practice. METHODS: This study involved a comparison of colonoscopy records of two community hospitals (January 2015-December 2016) for underwater polypectomy (n = 195) and gas insufflation polypectomy (n = 186). RESULTS: Comparable demographics, procedural data, overall distribution, morphology and size of resected lesions, number of en bloc and R0 resections (any polyp morphology and size); exception: overall, underwater polypectomy pedunculated polyps were significantly larger than those in the gas insufflation polypectomy group, p = 0.030. Underwater polypectomy (median, min) resection time was significantly shorter than gas insufflation polypectomy: sessile and flat polyps 6-9 mm, 0.8 vs 2.7 (p = 0.040); 10-19 mm, 2.0 vs 3.3 (p = 0.025), respectively; pedunculated polyps 6-19 mm, 0.8 vs 3.3 (p < 0.001). Underwater polypectomy resection of pedunculated polyps 6-19 mm showed significantly less immediate bleeding: 11.1% vs 1.5%, respectively (p = 0.031). CONCLUSIONS: Underwater polypectomy can be efficaciously used in routine clinical practice for the complete resection of colon polyps, with several advantages over gas insufflation polypectomy.

Water exchange for screening colonoscopy increases adenoma detection rate: a multicenter, double-blinded, randomized controlled trial.

Background and study aims Single-center studies, which were retrospective and/or involved unblinded colonoscopists, have suggested that water exchange, but not water immersion, compared with air insufflation significantly increases the adenoma detection rate (ADR), particularly in the proximal and right colon. Head-to-head comparison of the three techniques with ADR as primary outcome and blinded colonoscopists has not been reported to date. In a randomized controlled trial with blinded colonoscopists, we aimed to evaluate the impact of the three insertion techniques on ADR. Patients and methods A total of 1224 patients aged 50 - 70 years (672 males) and undergoing screening colonoscopy were randomized 1:1:1 to water exchange, water immersion, or air insufflation. Split-dose bowel preparation was adopted to optimize colon cleansing. After the cecum had been reached, a second colonoscopist who was blinded to the insertion technique performed the withdrawal. The primary outcome was overall ADR according to the three insertion techniques (water exchange, water immersion, and air insufflation). Secondary outcomes were other pertinent overall and right colon procedure-related measures. Results Baseline characteristics of the three groups were comparable. Compared with air insufflation, water exchange achieved a significantly higher overall ADR (49.3 %, 95 % confidence interval [CI] 44.3 % - 54.2 % vs. 40.4 % 95 %CI 35.6 % - 45.3 %; P  = 0.03); water exchange showed comparable overall ADR vs. water immersion (43.4 %, 95 %CI 38.5 % - 48.3 %; P  = 0.28). In the right colon, water exchange achieved a higher ADR than air insufflation (24.0 %, 95 %CI 20.0 % - 28.5 % vs. 16.9 %, 95 %CI 13.4 % - 20.9 %; P  = 0.04) and a higher advanced ADR (6.1 %, 95 %CI 4.0 % - 9.0 % vs. 2.5 %, 95 %CI 1.2 % - 4.6 %; P = 0.03). Compared with air insufflation, the mean number of adenomas per procedure was significantly higher with water exchange (P = 0.04). Water exchange achieved the highest cleanliness scores (overall and in the right colon). These variables were comparable between water immersion and air insufflation. Conclusions The design with blinded observers strengthens the validity of the observation that water exchange, but not water immersion, can achieve significantly higher adenoma detection than air insufflation. Based on this evidence, the use of water exchange should be encouraged.Trial registered at ClinicalTrials.gov (NCT02041507).

Impact of carbon dioxide insufflation and water exchange on postcolonoscopy outcomes in patients receiving on-demand sedation: a randomized controlled trial.

BACKGROUND AND AIMS: Water exchange (WE) is the least painful insertion method during colonoscopy. Its impact on postcolonoscopy discomfort has not been well-described. Carbon dioxide (CO2) insufflation consistently reduced postcolonoscopy discomfort. We compared postcolonoscopy outcomes of various combinations of insertion and withdrawal techniques (insertion-withdrawal modality): WE-CO2, WE-air insufflation (WE-AI), and CO2-CO2. METHODS: A total of 240 patients undergoing on-demand sedation diagnostic colonoscopy were randomized to WE-CO2 (n = 79), WE-AI (n = 80), CO2-CO2 (n = 81), with postprocedural data collected up to 24 hours. The primary outcome was postcolonoscopy bloating. Other postcolonoscopy outcomes included pain scores, flatus and incontinence episodes, toilet use, interference with normal activities, patient satisfaction, and patient willingness to repeat the procedure. RESULTS: Demographic and procedural data were comparable. Compared with WE-AI, WE-CO2 and CO2-CO2 resulted in significantly less bloating (all P < .0005) and lower pain scores (P values ranged from .008 to < .0005) up to 3 hours and fewer flatus episodes up to 6 hours (P values ranged from .003 to < .0005). WE-CO2 resulted in less interference with same-day activities compared with WE-AI (P = .043). The differences in postprocedural outcomes were significant, but the magnitude was small. Patient satisfaction and willingness to repeat the procedure were high and comparable among groups. WE was the least painful insertion technique (P < .0005). CONCLUSIONS: The combination WE-CO2 appears to be the optimal choice to decrease pain during the examination and to reduce bloating and other undesired procedural outcomes afterward. If a CO2 insufflator is already available, it seems advisable to adopt the combination WE-CO2. In the absence of a CO2 insufflator, the cost effectiveness of the addition of withdrawal CO2 to WE in diagnostic and nondiagnostic settings needs to be critically assessed. (Clinical trial registration number: NCT02409979.).

Insertion water exchange increases right colon adenoma and hyperplastic polyp detection rates during withdrawal.

BACKGROUND: Single site studies in male Veterans in the U.S. reported increased detection of presumptive cancer precursors (adenomas, hyperplastic polyps) in the proximal colon (cecum-splenic flexure) by water exchange. AIMS: Assess the reproducibility of the observation. METHODS: Analysis of secondary outcomes collected prospectively in 3 similarly designed randomized controlled trials using water exchange, water immersion and insufflation (air or carbon dioxide). MAIN OUTCOME: detection rates of adenomas and hyperplastic polyps in proximal, transverse and right colon (cecum-ascending). RESULTS: 704 males (173 screening) were evaluated. In the proximal colon, WE showed increased detection of small adenomas (p=0.009) and adenomas plus hyperplastic polyps (p=0.015) (vs insufflation); increased detection of adenomas plus hyperplastic polyps of any size (p=0.045) and of small size (p=0.04) (vs water immersion). In the right colon water exchange increased detection of small adenomas (19% vs 12.1%, p=0.04) (vs insufflation); small adenomas (19% vs 12%, p=0.038), adenomas plus hyperplastic polyps of any size (25% vs 16.7%, p=0.028) and of small size (23.7% vs 14.6%, p=0.012) (vs water immersion). Water exchange significantly improved bowel cleanliness. Sedation had no impact on lesion detection. CONCLUSIONS: Water exchange is a superior insertion technique for detection of adenomas and hyperplastic polyps primarily in the right colon, especially those of small size.

Impact of Colonoscopy Insertion Techniques on Adenoma Detection.

BACKGROUND: Low adenoma detection rate (ADR) predicts development of interval cancers, found mainly in the right (cecum-ascending) colon, where poor bowel preparation is an associated factor. Single-site studies reported increased detection of adenomas in the proximal colon segments by water exchange (WE). Data about colon cleansing revealed that WE had the greatest impact in the right colon. AIMS: To test the hypothesis that WE had the greatest impact on ADR in colon segments with the most favorable bowel cleanliness scores, namely the right colon. METHODS: We pooled right colon and overall ADR data of three similarly designed colonoscopy trials that compared WE, water immersion (WI) and insufflation of air or carbon dioxide (AICD) in a mixed gender European population. RESULTS: In this study, 1200 (704 males) subjects and were included. 288 were screening cases. Demographic and procedural data were comparable. Water exchange achieved significantly higher right colon <10 mm ADR (11.9 %, vs WI 6.9 %, p = 0.016; vs AICD 7.2 %, p = 0.025). Water exchange achieved the lowest proportions of poor bowel preparation and the highest right colon and overall Boston bowel preparation scale scores (p range 0.003, <0.0005). In patients with right colon excellent bowel cleanliness, water exchange was the only method significantly associated with right colon adenoma detection. One of the limitations is unblinded colonoscopists. CONCLUSIONS: In a mixed gender European population, water exchange is confirmed to be a superior insertion technique showing a significant increase in <10 mm right colon adenoma detection, achieving the cleanest colon and lowest proportions of poor bowel preparation requiring repeat procedures. CLINICALTRIALS. GOV NO: NCT01781650, 01954862, 01780818.

Evidence to suggest adoption of water exchange deserves broader consideration: Its pain alleviating impact occurs in 90% of investigators.

AIM: To determine whether observations were reproducible among investigators. METHODS: From March 2013 through June 2014, 18-85-year-old diagnostic and 50-70-year-old screening patients were enrolled at each center to on-demand sedation colonoscopy with water exchange (WE), water immersion (WI) and insufflation with air or CO2 for insertion and withdrawal [air or carbon dioxide (AICD)]. Data were aggregated for analysis. PRIMARY OUTCOME: Variations in real-time maximum insertion pain (0 = none, 1-2 = discomfort, 10 = worst). RESULTS: One thousand and ninety-one cases analyzed: WE (n = 371); WI (n = 338); AICD (n = 382). Demographics and indications were comparable. The WE group had the lowest real-time maximum insertion pain score, mean (95%CI): WE 2.8 (2.6-3.0), WI 3.8 (3.5-4.1) and AICD 4.4 (4.1-4.7), P < 0.0005. Ninety percent of the colonoscopists were able to use water exchange to significantly decrease maximum insertion pain scores. One investigator had high insertion pain in all groups, nonetheless WE achieved the lowest real-time maximum insertion pain score. WE had the highest proportions of patients with painless unsedated colonoscopy (vs WI, P = 0.013; vs AICD, P < 0.0005); unsedated colonoscopy with only minor discomfort (vs AICD, P < 0.0005), and completion without sedation (vs AICD, P < 0.0005). CONCLUSION: Aggregate data confirm superiority of WE in lowering colonoscopy real-time maximum insertion pain and need for sedation. Ninety percent of investigators were able to use water exchange to significantly decrease maximum insertion pain scores. Our results suggest that the technique deserves consideration in a broader scale.

Water Exchange Is the Least Painful Colonoscope Insertion Technique and Increases Completion of Unsedated Colonoscopy.

BACKGROUND & AIMS: Unsedated colonoscopy is acceptable for diagnostic, surveillance, and screening indications worldwide. However, insertion of the colonoscope can be painful; it is not clear which technique is least painful and thereby increases the likelihood of colonoscopy completion. We performed a head-to-head comparison of air insufflation (AI), carbon dioxide (CO2) insufflation, water immersion (WI), and water exchange (WE) to determine which combination of insertion techniques produces the least amount of pain. METHODS: In a patient-blinded prospective trial, 624 subjects were assigned randomly to groups that underwent colonoscopy with AI-AI, CO2-CO2, WI-AI, WE-AI, WI-CO2, or WE-CO2 insertion and withdrawal techniques, including on-demand sedation, at the St. Barbara Hospital (Iglesias, Italy) or the Vìtkovice Hospital (Ostrava, Czech Republic), from October 2013 through June 2014. The primary outcome was real-time maximum insertion pain (0 = none, 10 = worst), recorded by an unblinded nurse assistant. At discharge, a blinded observer recorded the recalled maximum insertion pain and patients' and investigators' guesses about method or gas used. RESULTS: Patients and investigators correctly guessed the method used for fewer than 44% of procedures, confirming adequate blinding. The correlation between real-time and recalled maximum insertion pain (r = 0.9; P < .0005) confirmed internal validation of the primary outcome. The WE group had the lowest scores: mean pain values were 5.2 for AI-AI (95% confidence interval [CI], 4.6-5.8), 4.9 for CO2-CO2 (95% CI, 4.3-5.4), 4.3 for WI-CO2 (95% CI, 3.8-4.9), 4.0 for WI-AI (95% CI, 3.5-4.5), 3.1 for WE-CO2 (95% CI, 2.7-3.4), and 3.1 for WE-AI (95% CI, 2.7-3.6) (P < .0005). The highest proportions of patients completing unsedated colonoscopy were in the WE groups. WE groups also had significantly better colon cleanliness, particularly in the transverse and right colon (P < .0005). One limitation of the study was that colonoscopists and assistants were not blinded to water-aided insertion methods. CONCLUSIONS: In a prospective study of colonoscopy insertion methods, CO2 insufflation did not reduce real-time maximum insertion pain. Compared with AI or CO2, WI and WE reduced insertion pain. The least painful technique was WE, which significantly increased completion of unsedated colonoscopy and bowel cleanliness without prolonging insertion time. ClinicalTrials.gov number: NCT01954862.

A randomized, controlled trial comparing real-time insertion pain during colonoscopy confirmed water exchange to be superior to water immersion in enhancing patient comfort.

BACKGROUND: A recent American Society for Gastrointestinal Endoscopy Technology Status Evaluation Report recommended comparative studies of water-aided colonoscopy methods to refine the optimal insertion technique. OBJECTIVE: Air insufflation (AI), water immersion (WI), and water exchange (WE) were compared head-to-head to test the hypothesis that WE produces the least insertion pain. DESIGN: Patient-blinded, prospective, randomized, controlled trials. SETTING: Two community hospitals in Italy. PATIENTS: First-time diagnostic or screening colonoscopy in unsedated patients with the option of on-demand sedation. INTERVENTION: Colonoscopy with AI, WI, or WE. MAIN OUTCOME MEASUREMENTS: Real-time maximum insertion pain (0 = none, 10 = worst). To avoid interventional bias, the timing of recording was at the discretion of the nurse assistant. Adjunct measures were implemented to ensure patient perception of minimal discomfort. Recalled pain and patients' guess of insertion methods were recorded after colonoscopy. RESULTS: Results were merged for 576 randomized patients. Correct patient guesses lower than 33% confirmed adequate blinding. Significant correlation (Pearson coefficient 0.6, P < .0005) between real-time and recalled pain provided internal validation of the former as the primary outcome. Real-time pain (95% confidence interval [CI]: AI, 4.1 [3.7-4.5]; WI, 3.5 [3.0-3.9]; and WE, 2.5 [2.2-2.9] [P < .0005] was the lowest in the WE group. The proportions of patients completing unsedated colonoscopy based on the assigned methods were significantly different (WE, 74.7% vs WI, 62.4%; P = .009; vs AI, 65.3%; P = .04). WE required the least implementation of adjunct maneuvers. LIMITATIONS: Unblinded colonoscopists. CONCLUSION: The current findings with an internally validated primary outcome in adequately blinded patients support the hypothesis that WE is superior to WI in attenuating real-time insertion pain and enhancing completion of unsedated colonoscopy.

A two-center randomized controlled trial of water-aided colonoscopy versus air insufflation colonoscopy.

BACKGROUND AND STUDY AIM: Water-aided colonoscopy includes water immersion and water exchange. Several small single-center studies have suggested that the use of water rather than air insufflation during colonoscopy reduces pain on insertion. The aim of this study was to investigate whether water-aided colonoscopy is less painful than air insufflation in a large cohort of patients. PATIENTS AND METHODS: This was a two-center, randomized controlled trial. Consecutive patients who agreed to start colonoscopy without premedication were included. Sedation was administered on demand. Water-aided colonoscopy was performed using water immersion in the early phase of the study, and subsequently water exchange was used. The primary endpoint was cecal intubation with pain scores of ≤ 2 and sedation with no or ≤ 2 mg midazolam. Secondary outcomes were pain score at discharge, cecal intubation rate and time, and adenoma detection rate (ADR). RESULTS: A total of 672 patients were randomized to water exchange (n = 338) or air insufflation (n = 334). The primary endpoint was achieved in more patients in the water exchange group (83.8 % vs. 62 %; P < 0.0005). On-demand sedation was also required less (11.5 % vs. 26.0 %; P < 0.0005) and mean pain score was lower (1.3 vs. 2.3; P < 0.0005) in the water exchange group. The cecal intubation rates were comparable. Water exchange had a significantly higher overall ADR (25.8 % vs. 19.1 %; P = 0.041), proximal ADR (10.1 % vs. 4.8 %; P = 0.014), and proximal < 10 mm ADR (7.7 % vs. 3.9 %; P = 0.046); proximal ADR was also higher in screening-only patients in the water exchange group (18.9 % vs. 7.4 %; P  = 0.015). No detailed analysis was possible for the air insufflation vs. water immersion comparison. CONCLUSION: The current results confirmed that water exchange minimized the requirement for sedation and increased the ADR.