Low-volume polyethylene glycol and bisacodyl for bowel preparation prior to colonoscopy: a meta-analysis

BACKGROUND Quality of bowel preparation prior to colonoscopy is essential. Studies have shown a reduced volume of polyethylene glycol (PEG) with bisacodyl may improve visualization and tolerability, but results have varied. Therefore, a meta-analysis was performed to analyze the efficacy of a low-volume PEG bowel preparation with bisacodyl for bowel preparation prior to colonoscopy. METHODS Multiple databases were searched (June 2012). Only randomized controlled trials in peer-reviewed journals on adult subjects comparing low-volume PEG (2 L) with bisacodyl versus 4 L PEG were included. Meta-analysis for the efficacy of low-volume PEG with bisacodyl and 4 L PEG were analyzed by calculating pooled estimates of number of satisfactory, excellent, and poor bowel preparations as well as adverse patient events (abdominal pain, nausea, vomiting, bloating). RESULTS Six studies (N=1,540) met the inclusion criteria. No statistically significant differences were noted between low-volume PEG (2 L) with bisacodyl and 4 liters PEG for number of satisfactory (OR 0.86; 95% CI: 0.45-1.63, P=0.64), excellent (OR 1.08; 95% CI: 0.78-1.50, P=0.63), or poor bowel preparations (OR 0.68; 95% CI: 0.35-1.34, P=0.27). A statistically significant decrease in nausea (OR 0.57; 95% CI: 0.36-0.89, P=0.01), vomiting (OR 0.57; 95% CI: 0.40-0.81, P<0.01), and bloating (OR 0.65; 95% CI: 0.49-0.87, P<0.01) was noted for the low-volume PEG with bisacodyl as compared to 4 L PEG. No statistically significant differences were noted between the two groups for abdominal pain (P=0.62). CONCLUSION Low-volume PEG (2 L) with bisacodyl demonstrates less nausea, vomiting, and bloating without adversely affecting the bowel preparation.