A head-to-head comparison of 4-L polyethylene glycol and low-volume solutions before colonoscopy: which is the best? A multicentre, randomized trial

Cleaning effect and tolerance of 16 bowel preparation regimens on adult patients before colonoscopy: a network meta-analysis

PURPOSE

Colonoscopy is the gold standard for the diagnosis of colorectal cancer (CRC). Before a colonoscopy, an adequate bowel preparation (BP) is required. Currently, more novel regimens with different effects have been proposed and used successively. This network meta-analysis aims to compare the cleaning effects and patients' tolerability of several BP regimens.

METHODS

We performed a network meta-analysis of randomized controlled trials including sixteen kinds of BP regimens. We searched PubMed, Cochrane Library, Embase, and Web of Science databases. The outcomes of this study were bowel cleansing effect and tolerance.

RESULTS

We included a total of 40 articles with 13,064 patients. For the primary outcomes, polyethylene glycol (PEG) + ascorbic acid (Asc) + simethicone (Sim) (OR, 14.27, 95%CrI, 2.68-127.87) regimen is ranked first in Boston Bowel Preparation Scale (BBPS). PEG + Sim (OR, 2.0, 95%CrI 0.64-6.4) regimen is ranked first in Ottawa Bowel Preparation Scale (OBPS), but without significant differences. For the secondary outcomes, PEG + Sodium Picosulfate/Magnesium Citrate (SP/MC) (OR, 4.88e + 11, 95%CrI, 39.56-1.82e + 35) regimen is the best in cecal intubation rate(CIR). PEG + Sim (OR,1.5, 95%CrI, 1.0-2.2) regimen is ranked first in adenoma detection rate(ADR). Senna (OR, 3.23, 95%CrI, 1.04-9.97) and SP/MC (OR, 249.91, 95%CrI, 78.49-958.19) regimens are ranked first in abdominal pain and willingness to repeat, respectively. There is no significant difference in cecal intubation time (CIT), polyp detection rate (PDR), nausea, vomiting, and abdominal bloat.

CONCLUSION

PEG + Asc + Sim regimen is more effective at cleaning the bowel. PEG + SP/MC will be helpful to increase CIR. For ADR, PEG + Sim regimen will be more helpful. In addition, PEG + Asc + Sim is the least likely to cause abdominal bloat, while Senna regimen is more likely to cause abdominal pain. Patients prefer to re-use the SP/MC regimen for bowel preparation.

A multicenter randomized phase 4 trial comparing sodium picosulphate plus magnesium citrate vs. polyethylene glycol plus ascorbic acid for bowel preparation before colonoscopy. The PRECOL trial

Background

Adequate bowel preparation before colonoscopy is crucial. Unfortunately, 25% of colonoscopies have inadequate bowel cleansing. From a patient perspective, bowel preparation is the main obstacle to colonoscopy. Several low-volume bowel preparations have been formulated to provide more tolerable purgative solutions without loss of efficacy.

Objectives

Investigate efficacy, safety, and tolerability of Sodium Picosulphate plus Magnesium Citrate (SPMC) vs. Polyethylene Glycol plus Ascorbic Acid (PEG-ASC) solutions in patients undergoing diagnostic colonoscopy.

Materials and methods

In this phase 4, randomized, multicenter, two-arm trial, adult outpatients received either SPMC or PEG-ASC for bowel preparation before colonoscopy. The primary aims were quality of bowel cleansing (primary endpoint scored according to Boston Bowel Preparation Scale) and patient acceptance (measured with six visual analogue scales). The study was open for treatment assignment and blinded for primary endpoint assessment. This was done independently with videotaped colonoscopies reviewed by two endoscopists unaware of study arms. A sample size of 525 patients was calculated to recognize a difference of 10% in the proportion of successes between the arms with a two-sided alpha error of 0.05 and 90% statistical power.

Results

Overall 550 subjects (279 assigned to PEG-ASC and 271 assigned to SPMC) represented the analysis population. There was no statistically significant difference in success rate according to BBPS: 94.4% with PEG-ASC and 95.7% with SPMC (P = 0.49). Acceptance and willing to repeat colonoscopy were significantly better for SPMC with all the scales. Compliance was less than full in 6.6 and 9.9% of cases with PEG-ASC and SPMC, respectively (P = 0.17). Nausea and meteorism were significantly more bothersome with PEG-ASC than SPMC. There were no serious adverse events in either group.

Conclusion

SPMC and PEG-ASC are not different in terms of efficacy, but SPMC is better tolerated than PEG-ASC. SPMC could be an alternative to low-volume PEG based purgative solutions for bowel preparation.

Clinical trial registration

[ClinicalTrials.gov], Identifier [NCT01649674 and EudraCT 2011-000587-10].

Efficacy of ultra-low volume (≤1 L) bowel preparation fluids: Systematic review and meta-analysis

BACKGROUND AND AIMS

High-quality bowel preparation is paramount for the diagnostic accuracy and safety of colonoscopy; however, it is often difficult for patients to adhere to high-volume laxatives, which may contribute to poor bowel preparation. This review aims to assess the efficacy of bowel preparation fluids of 1 L or less (≤1 L).

METHODS

We performed a systematic review including all relevant randomized controlled trials on ultra-low volume (≤1 L) bowel preparation fluids for colonoscopy published since 2015. Primary endpoint was the percentage of adequately prepared patients. Secondary endpoints included adenoma detection rate (ADR) and safety.

RESULTS

Bowel preparation with sodium picosulfate/magnesium citrate (SPMC; 19 trials, n = 10,287), 1L-polyethylene glycol with ascorbate (PEGA; 10 trials, n = 1717), sodium phosphate (NaP; 2 trials, n = 621), and oral sulfate solution (OSS; 3 trials, n = 597) was adequate in 75.2%, 82.9%, 81.9%, and 92.1%, respectively, of patients; however, heterogeneity between studies was considerable (I² range: 86-98%). Pooled ADRs were 31.1% with SPMC, 32.3% with 1L-PEGA, 30.4% with NaP, and 40.9% with OSS. Temporary electrolyte changes were seen with all ultra-low volume bowel preparation fluid solutions but without sustained effects in most patients.

CONCLUSION

Ultra-low volume bowel preparation fluids do not always meet the 90% quality standard for adequate bowel preparation as defined by current guidelines. Nonetheless, they may be considered in patients intolerant for higher-volume laxatives and without risk factors for inadequate bowel preparation or dehydration-related complications.

Novel frontiers of agents for bowel cleansing for colonoscopy

The incidence of colorectal cancer (CRC) is characterized by rapid declines in the wake of widespread screening. Colonoscopy is the gold standard for CRC screening, but its accuracy is related to high quality of bowel preparation (BP). In this review, we aimed to summarized the current strategy to increase bowel cleansing before colonoscopy. Newly bowel cleansing agents were developed with the same efficacy of previous agent but requiring less amount of liquid to improve patients’ acceptability. The role of the diet before colonoscopy was also changed, as well the contribution of educational intervention and the use of adjunctive drugs to improve patients’ tolerance and/or quality of BP. The review also described BP in special situations, as lower gastrointestinal bleeding, elderly people, patients with chronic kidney disease, patients with inflammatory bowel disease, patients with congestive heart failure, inpatient, patient with previous bowel resection, pregnant/lactating patients. The review underlined the quality of BP should be described using a validate scale in colonoscopy report and it explored the available scales. Finally, the review explored the possible contribution of bowel cleansing in post-colonoscopy syndrome that can be related by a transient alteration of gut microbiota. Moreover, the study underlined several points needed to further investigations.

Comparison of 1L Adjuvant Auxiliary Preparations with 2L Solely Polyethylene Glycol plus Ascorbic Acid Regime for Bowel Cleaning: A Meta-analysis of Randomized, Controlled Trials

The effectiveness of additional usage of adjuvants for bowel preparation is still unclear. This study compared 1L polyethylene glycol plus ascorbic acid with adjuvant drug regimens (1L PEG-AA, lower volume) with 2L polyethylene glycol plus ascorbic acid (2L PEG-A, low volume) to evaluate whether the adjuvants can be used to reduce the standard dosage of purgative further. The PubMed/MEDLINE, EMBASE, Cochrane Library, and Web of Science database were searched for randomized controlled trials (RCTs). The primary outcome was the efficacy of bowel preparation, and the secondary outcomes were patients' tolerability and complication rate. The overall quality of evidence was assessed using the GRADEpro guideline development tool. Five RCTs with a total of 1013 patients from Korea were included. The majority of patients were outpatients from different hospitals. The pooled data showed no significant difference in the adequate bowel preparation rate (89.3% versus 89.4%, RR 1, 95% CI 0.95-1.05, I ² = 47%) as well as in the complication rate (RR for nausea 1.22, 95% CI 0.89-1.65, I ² = 49%; RR for bloating 0.96, 95% CI 0.73-1.28, I ² = 0%; RR for vomiting 0.69, 95% CI 0.32-1.50, I ² = 33%; RR for abdominal pain 1.01, 95% CI 0.61-1.69, I ² = 0%). But a significantly higher willingness rate was observed in the lower volume (85.1% versus 67.9%, RR 1.25, 95% CI 1.14-1.38, I ² = 46%). The quality of primary outcome evidence was moderate. The findings of this meta-analysis revealed that 1L PEG-AA may be a viable alternative to 2L PEG-A, with comparable effectiveness, better patient preference, and no statistically significant adverse event occurrence.

Efficacy and Patient Tolerability of Split-Dose Sodium Picosulfate/Magnesium Citrate (SPMC) Oral Solution Compared to the Polyethylene Glycol (PEG) Solution for Bowel Preparation in Outpatient Colonoscopy: An Evidence-Based Review

Background

Colonoscopy is the gold standard exam for evaluation of colonic abnormalities and for screening and surveillance for colorectal cancer. However, the efficacy of colonoscopy is dependent on the quality of the pre-colonoscopy bowel preparation. Polyethylene glycol (PEG) and sodium picosulfate/magnesium citrate (SPMC) have emerged as two of the most commonly used bowel preparation agents. We conducted an evidence-based review of current evidence to further investigate the efficacy and patient tolerability of split-dose SPMC oral solution compared to PEG solution for colonoscopy bowel preparation.

Methods

A systematic search was performed using Pubmed (MEDLINE), Web of Science, EMBASE, and Cochran Central Register of Controlled Trials databases. All studies on split-dose bowel preparation with SPMC and PEG were reviewed. Relevant studies regarding colonoscopy and bowel preparations were also included. Randomized controlled trials were prioritized due to the high quality of evidence.

Results

Eight randomized controlled trials were included. Split-dose SPMC and PEG were associated with similar results for adequacy of bowel preparation. Split-dose SPMC was associated with increased patient tolerability and compliance.

Conclusion

Split-dose SPMC and PEG are both adequate and safe for bowel preparation for outpatient colonoscopy, with split-dose SPMC being more tolerable for patients. Additional RCTs comparing these and other bowel preparation solutions are necessary to further investigate quality of bowel preparation, patient preference, and cost-effectiveness of the various options.

Effectiveness of concomitant use of green tea and polyethylene glycol in bowel preparation for colonoscopy: a randomized controlled study

BACKGROUND

Polyethylene glycol solution (PEG) is widely used for bowel preparation prior to colonoscopies. However, patients often exhibited adverse events as nausea, vomit and distention due to its uncomfortable tastes and potential side affects. This study aimed to evaluate the effectiveness and safety of concomitant use of green tea (GT) with PEG in bowel preparation prior to colonoscopy.

METHODS

This was a prospective, randomized controlled study. It was conducted at an outpatient setting of colorectal surgery in a tertiary hospital. Patients aged 18 through 80 who were scheduled to undergo colonoscopy between August 2015 and February 2016 were randomly assigned into two groups, admitting either 2 L-PEG solutions with 1 L GT liquids or 2 L-PEG solutions only for bowel preparation. Admitted doses of PEG solutions, taste evaluation, adverse reactions (nausea and vomiting, distention and abdominal pain) were investigated by questionnaires. The bowel cleanliness of each patient was evaluated according to the Aronchick indicators.

RESULTS

A total of 116 patients were enrolled in this study (PEG+GT 59, PEG 57). Full compliances were achieved in 93.2% patients of group PEG+GT and 59.6% of group PEG (p < 0.001). Mean Aronchick scale between two groups were 2.0 ± 0.9 versus 2.2 ± 0.7 respectively (PEG+GT vs PEG, p = 0.296). Rates of adverse events as nausea and vomiting, abdominal pain in bowel preparation were significantly different between two groups (55.9% vs 77.2%, p = 0.015 and 13.6% vs 33.3%, p = 0.012). Patients in group PEG+GT who have probabilities to receive repeating colonoscopy had a higher willingness to accept PEG+GT again for bowel preparation, compared with PEG group (94.9% vs 57.9%, p < 0.001).

CONCLUSIONS

Concomitant use of green tea and polyethylene glycol may effectively reduce incidence of adverse events, increase compliances, with comparable bowel cleanliness in bowel preparation.

TRIAL REGISTRATION

This trial was retrospectively registered on Feb 1st, 2019 (ChiCTR1900021178).

Randomized, double-blinded, placebo-controlled trial evaluating simethicone pretreatment with bowel preparation during colonoscopy

BACKGROUND

The presence of small air bubbles and foam are an impediment to a successful colonoscopy. They impair an endoscopist’s view and diminish the diagnostic accuracy of the study. This has been particularly noted to be of concern with the switch to lower volume polyethylene glycol (PEG) and bisacodyl combination preparation.

AIM

To evaluate the effect of oral simethicone addition to bowel preparation on intraluminal bubbles reduction during colonoscopy.

METHODS

Described is a prospective, randomized, multi-center, double-blinded, placebo-controlled study to evaluate the use of premixed simethicone formulation with split-regimen, low-volume PEG-bisacodyl combination bowel preparation for 168 outpatients undergoing screening, surveillance, and diagnostic colonoscopies. Primary outcome includes evaluation of bubbles during colonoscopy graded using the Intraluminal Bubbles Scale. Secondary outcomes include evaluation of the Boston Bowel Preparation Scale (BBPS), total number of polyps, polyp size differentiation, polyp laterality, adenoma detection, mass detection, cecal insertion time, withdrawal time, and patient-reported adverse events.

RESULTS

Higher Intraluminal Bubbles grades III and IV (less than 75% of the mucosa cleared of bubbles/foam requiring intervention with simethicone infused wash) were detected in the placebo group [Simethicone n = 4/84 vs Placebo n = 20/84 (P = 0.007)]. BBPS total score was 7.42 [standard deviation (SD) = ± 1.51] in the simethicone group and 7.28 (SD = ± 1.44) in the placebo group (P = 0.542) from a total of 9. Significantly higher number of adenomas were detected in the simethicone group (P = 0.001).

CONCLUSION

The addition of simethicone to bowel preparation is well advised for its anti-foaming properties. The results of this study suggest that addition of oral simethicone can improve bowel wall visibility.

Viewpoints of the target population regarding barriers and facilitators of colorectal cancer screening in the Czech Republic

BACKGROUND

Public awareness of colorectal cancer (CRC) and uptake of CRC screening remain challenges. The viewpoints of the target population (asymptomatic individuals older than 50) regarding CRC screening information sources and the reasons for and against participation in CRC screening are not well known in the Czech Republic. This study aimed to acquire independent opinions from the target population independently on the health system.

AIM

To investigate the viewpoints of the target population regarding the source of information for and barriers and facilitators of CRC screening.

METHODS

A survey among relatives (aged 50 and older) of university students was conducted. Participants answered a questionnaire about sources of awareness regarding CRC screening, reasons for and against participation, and suggestions for improvements in CRC screening. The effect of certain variables on participation in CRC screening was analyzed.

RESULTS

Of 498 participants, 478 (96%) respondents had some information about CRC screening and 375 (75.3%) had participated in a CRC screening test. General practitioners (GPs) (n = 319, 64.1%) and traditional media (n = 166, 33.3%) were the most common information sources regarding CRC screening. A lack of interest or time and a fear of colonoscopy or positive results were reported as reasons for non-participation. Individuals aged > 60 years [adjusted odds ratio (aOR) = 2.30, 95% confidence interval (CI) (1.42-3.71), P = 0.001], females (aOR = 1.95, 95%CI (1.26-3.01) P = 0.003), and relatives of CRC patients (aOR = 4.17, 95%CI (1.82-9.58) P = 0.001) were more likely to participate in screening. Information regarding screening provided by physicians - GPs: (aOR = 8.11, 95%CI (4.90-13.41), P < 0.001) and other specialists (aOR = 4.19, 95%CI (1.87-9.38), P = 0.001) increased participation in screening. Respondents suggested that providing better explanations regarding screening procedures and equipment for stool capturing could improve CRC screening uptake.

CONCLUSION

GPs and other specialists play crucial roles in the successful uptake of CRC screening. Reduction of the fear of colonoscopy and simple equipment for stool sampling might assist in improving the uptake of CRC screening.