A low-volume polyethylene glycol solution was associated with an increased suboptimal bowel preparation rate but had similar recommendations for an early repeat colonoscopy, procedure times, and adenoma detection rates

Comparing the Real-World Effectiveness of High- Versus Low-Volume Split Colonoscopy Preparations: An Experience Through the British Columbia Colon Cancer Screening Program

Background

The British Columbia Colon Screening Program (BCCSP) is a population-based colon cancer screening program. In December 2018, physicians in Vancouver, Canada agreed to switch from a low-volume split preparation to a high-volume polyethylene glycol preparation after a meta-analysis of studies suggested superiority of the higher volume preparation in achieving adequate bowel cleansing and improving adenoma detection rates.

Aims

To compare the quality of bowel preparation and neoplasia detection rates using a high-volume split preparation (HVSP) versus a low-volume split preparation (LVSP) in patients undergoing colonoscopy in the BCCSP.

Methods

A retrospective review of patients undergoing colonoscopy through the BCCSP at St. Paul’s Hospital from July 2017 to November 2018 and December 2018 to November 2019 was conducted. Inclusion criteria included age 50 to 74 and patients undergoing colonoscopy through the BCCSP. Variables collected included patient demographics and bowel preparation quality. Rates of bowel preparation and neoplasia detection were analyzed using chi-squared test.

Results

A total of 1453 colonoscopies were included, 877 in the LVSP group and 576 in the HVSP group. No statistically significant difference was noted between rates of inadequate bowel preparation (LVSP 3.6% versus HVSP 2.8%; P = 0.364). Greater rates of excellent (48.4% versus 40.1%; P = 0.002) and optimal (90.1% versus 86.5%; P = 0.041) bowel preparation were achieved with HVSP. The overall adenoma detection rate was similar between the two groups (LVSP 53.1% versus HVSP 54.0%; P = 0.074). LVSP demonstrated higher overall sessile serrated lesion detection rate (9.5% versus 5.6%; P = 0.007).

Conclusions

Compared to LVSP, HVSP was associated with an increase in excellent and optimal bowel preparations, but without an improvement in overall neoplasia detection.

Comparison of Small Versus Large Volume Split Dose Preparation for Colonoscopy: A Study of Colonoscopy Outcomes

BACKGROUND

Split dose bowel preparations (SDP) have superior outcomes for colonoscopy as compared to evening before regimens. However, the association of the actual volume of the SDP to colonoscopy outcome measures has not been well studied.

AIMS

Compare adenoma detection rate (ADR), sessile serrated polyp detection rate (SDR), mean bowel cleanse score, and predictors of inadequate exams between small volume SDP and large volume SDP.

METHODS

We have conducted a retrospective study in patients undergoing colonoscopy with small volume SDP versus large volume SDP between July 2014 and December 2014. Basic demographics (age, gender and BMI) along with clinical co-morbidities were recorded. Quality of the bowel preparation, ADR and SDR was compared between these groups. Univariate and multivariable logistic regressions were used to assess the determinants of inadequate exams in each group.

RESULTS

1573 patients with split dose preparation were included in this retrospective study. 58.4% (920/1573) patients took small volume SDP. There was no difference in ADR (37.9 vs. 38.8%, p = 0.2); however, SDR was higher for small volume SDP compared to large volume SDP (11.9 vs. 7.9% p = 0.005). There was no difference in the rate of inadequate exams between the two groups (p = 0.7). A history of diabetes and constipation was associated with inadequate exams only in the small volume SDP.

CONCLUSIONS

SDR was higher in small volume SDP. There was no difference in rate of inadequate exams between the two groups. A history of diabetes and constipation was associated with inadequate exams only in patients with the small volume SDP.