One-Day versus Three-Day Low-Residue Diet and Bowel Preparation Quality before Colonoscopy: A Multicenter, Randomized, Controlled Trial

BACKGROUND

One-day low-residue diet (LRD) is recommended before colonoscopy, but only three single-center trials compared the 1-day versus 3-day LRD. The aim of this multicenter study was to compare the impact of a 3-day versus 1-day LRD on its ability to adequately and successfully prepare the bowel of outpatients that require a colonoscopy. The outpatients' tolerance and adherence to the LRD were also considered.

METHODS

Consecutive outpatients were randomized to 1-day versus 3-day LRD at three open-access endoscopy units. The primary endpoint consisted of the proportion of patients with a satisfactory degree of bowel cleanliness (Score 2-3 on the Boston Bowel Preparation Scale [BBPS] in each segment). Secondary endpoints were patients' tolerance and adherence to the prescribed diet evaluated by a standardized questionnaire.

RESULTS

289 patients were included in the study (1-day LRD arm = 143, 3-day LRD arm = 146). BBPS ≥2 was not significantly different in the two dietary regimens in any of the three colonic segments (71% vs. 72%, p = 0.9). The percentage of patients with incomplete preparation was similar in the two arms (9% vs. 9%; p = 1.0). No significant differences were found among colonoscopy findings in terms of abnormalities (81% vs. 84%, p = 0.8). Both groups scored similarly in overall tolerance to LRD (48% vs. 49%, p = 1.0) and also in whether they would have adopted a different dietary regimen (p = 0.3).

CONCLUSION

Our multicenter randomized study confirmed that optimal bowel cleansing is reached through a 1-day LRD.

Oral antibiotics and a low-residue diet reduce the incidence of anastomotic leakage after left-sided colorectal surgery: a retrospective cohort study

PURPOSE

Anastomotic leakage is a potential complication after colorectal surgery. We investigated the effects of oral antibiotics and a low-residue diet on the incidence of anastomotic leakage after left-sided colorectal surgery.

METHODS

Outcomes were retrospectively compared between 64 patients who underwent mechanical bowel preparation alone (group A) and 183 patients who underwent mechanical bowel preparation with addition of oral kanamycin and metronidazole (group B) on the day before left-sided colorectal surgery. After surgery, patients in group A received a normal diet containing dietary fiber and those in group B received a low-residue diet. The primary outcome was the incidence of anastomotic leakage. Secondary outcomes were rates of other postoperative complications, length of postoperative hospital stay, and laboratory data.

RESULTS

Anastomotic leakage, surgical site infection, and diarrhea were less common in group B than in group A (4.9% vs 18.8%, 6.6% vs 23.4%, and 25.7% vs 43.8%, respectively). Postoperative C-reactive protein levels were significantly lower in group B. The median postoperative hospital stay was significantly shorter in group B than in group A (8 days vs 9 days, P = 0.010). Adaptive double least absolute shrinkage and selection operator regression revealed that use of preoperative oral antibiotics and a postoperative low-residue diet were associated with lower incidence of anastomotic leakage (odds ratio 0.163, 95% confidence interval 0.062-0.430; P < 0.001).

CONCLUSION

Oral antibiotics and a low-residue diet reduced the incidence of anastomotic leakage and shortened the postoperative hospital stay by 1 day.

Efficacy and tolerability of a low-residue diet for bowel preparation: systematic review and meta-analysis

BACKGROUND

Colorectal cancer (CRC) contributes significantly to cancer mortality worldwide. In an effort to reduce the risk of death, detection of polyps through colonoscopy is crucial. The success of the colonoscopy depends on the diet administered the day before the test. Our aim was to evaluate the efficacy, tolerability, and adverse effects of bowel preparation when using a low-residual diet (LRD) compared to a clear-liquid diet (CLD) the day before a scheduled colonoscopy.

METHODS

PubMed/Medline, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL) and Scopus databases were searched. We included studies of patients undergoing a scheduled colonoscopy for CRC screening and surveillance or for diagnostic purposes that compared a LRD with a CLD the day before the colonoscopy. Efficacy, the primary outcome, was evaluated as the rate of adequate bowel preparation. Secondary outcomes were tolerability and adverse effects of bowel preparation.

RESULTS

Thirteen RCTs (N = 2587) were included. Patients receiving a LRD compared to a CLD showed no difference in adequate bowel preparations (RR 1.02; 95% CI 0.99-1.05; I² = 60%). However, the LRD improved patient tolerability (RR 1.17; 95% CI 1.12-1.23; I² = 66%) and had fewer adverse effects (RR 0.89; 95% CI 0.84-0.94; I² = 73%) compared to the CLD. Groups using a LRD with 4L of polyethylene glycol in a single dose or a LRD with < 2000 kcal < 32 g of fibres/day had better tolerability.

CONCLUSION

Based on these findings, our recommendation is strong in favour of a LRD for bowel preparation of patients undergoing a scheduled colonoscopy. This diet could also be useful as a preoperative colonic preparation, but this requires further research.

Single-Day Low-Residue Diet Prior to Colonoscopy Demonstrates Improved Bowel Preparation Quality and Patient Tolerance over Clear Liquid Diet: A Randomized, Single-Blinded, Dual-Center Trial

BACKGROUND AND AIMS

Patients often refer to bowel preparation and associated dietary restrictions as the greatest deterrents to having a colonoscopy completed or performed. Large studies comparing a low-residue diet (LRD) and a clear liquid diet (CLD) are still limited. The aim of this study is to compare LRD and CLD with regard to bowel preparation quality, tolerance, and satisfaction among a diverse patient population.

METHODS

This study is a dual-center, randomized, single-blinded, prospective trial involving adult patients undergoing outpatient colonoscopy at the University of California Irvine Medical Center and an affiliated Veterans Administration hospital. Patients were randomized to consume either a CLD or a planned LRD for the full day prior to colonoscopy. Both groups consumed 4L split-dosed PEG-ELS. The adequacy of bowel preparation was evaluated using the Boston Bowel Preparation Score (BBPS). Adequate preparation was defined as a BBPS ≥ 6 with no individual segment less than a score of 2. Hunger and fatigue pre - and post-procedure were graded on a ten-point scale. Nausea, vomiting, bloating, abdominal cramping, overall discomfort, satisfaction with the diet, willingness to repeat the same preparation and overall experience were assessed.

RESULTS

A total of 195 subjects who underwent colonoscopy from October 2014 to October 2017 were included. The mean BBPS for the LRD and CLD groups was 8.38 and 7.93, respectively (p = 0.1). There was a significantly higher number of adequate preparations in the LRD group compared to CLD (p = 0.05). Evening hunger scores just before starting the bowel preparation were significantly lower in the LRD than the CLD group, 2.81 versus 5.97, respectively (p = 0.006). Subjects in the LRD group showed significantly less nausea (p = 0.047) and bloating (p = 0.04). Symptom scores for vomiting, abdominal cramping, and overall discomfort were similar between the groups. Satisfaction with diet was significantly higher in the LRD group than CLD, 72% versus 37.66%, respectively (p < 0.001). The overall colonoscopy experience and the satisfaction with the preparation itself were also better reported in the LRD group (p < 0.001 and p = 0.002, respectively).

CONCLUSIONS

This study, which included a diverse group of patients, demonstrated that patients using a LRD before colonoscopy achieve a bowel preparation quality that is superior to patients on a CLD restriction. This study shows that a low-residue diet improves patient satisfaction and results in significantly better tolerability of bowel preparation. As a less restrictive dietary regimen, the low-residue diet may help improve patient participation in colorectal cancer screening programs.

Increasing the low residue diet to 3 days does not improve the bowel cleansing in hard to prepare patients: Post hoc analysis of a randomized controlled trial

BACKGROUND

Recent evidence suggests that the number of low residue diet (LRD) days does not influence the bowel cleansing quality in non-selected patients. However, there are not data in the subgroup of patients with risk factors of inadequate bowel cleansing.

OBJECTIVE

The aim of this study was to assess whether a 3-day LRD improved the bowel cleansing quality in patients with risk factors of poor bowel cleansing.

PATIENTS AND METHODS

Post hoc analysis of a randomized controlled trial carried out between December 2017 and March 2018 in a tertiary care hospital. Patients with high risk of poor bowel cleansing were selected following a validated score. The patients were randomized to the 1-day LRD or 3-day LRD groups. All patients received a 2-L split-dose of polyethylene glycol plus ascorbic acid. Intention-to-treat (ITT) and per-protocol (PP) analyses were conducted for the main outcome.

RESULTS

135 patients (1-day LRD group=67, 3-day LRD=68) were included. The rate of adequate cleansing quality was not significantly different between the groups in the ITT analysis: 76.1%, 95% CI: [64.6-84.8] vs. 79.4%, 95% CI: [68.2-87.4]; odds ratio (OR) 1.2, 95% CI [0.54-2.73]) or in the PP analysis: 77.3%, 95% CI: [65.7-85.8] vs. 80.3%, 95% CI: [69.0-88.3]; OR 1.2, 95% CI [0.52-2.77]). Compliance with the diet or cleansing solution, satisfaction or difficulties with the LRD and the polyp/adenoma detection rates were not significantly different.

CONCLUSION

Our results suggest that 1-day LRD is not inferior to 3-day LRD in patients with risk factors of inadequate bowel cleansing.