Systematic review and meta-analysis: is bowel preparation still necessary in small bowel capsule endoscopy?

Introduction: Optimal bowel preparation for small bowel capsule endoscopy(SBCE) is controversial. This meta-analysis aimed to investigate the effects of laxatives in SBCE. Methods: A comprehensive literature search was conducted for studies investigating the use of laxatives in SBCE. The primary outcome was diagnostic yield(DY) for SB findings; secondary outcomes SB visualization quality(SBVQ) and completion rate(CR). Pooled odds ratios(ORs) with 95% confidence intervals(CIs) and number needed to treat(NNT) were calculated. Results: Forty studies (4380 patients with laxatives, 2185 without) were included. Laxative use did not improve DY of SB findings overall (OR 1.11 (95% CI 0.85-1.44)) or for significant SB findings (OR 1.10 (95% CI 0.76-1.60)). However, SBVQ improved with the use of laxatives (OR 1.60 (95% CI 1.08-2.06)), NNT 14. The OR for completed SBCE was 1.30 (95% CI 0.95-1.78). Patients given polyethylene glycol(PEG) had lower DY than sodium phosphate(NaP). SBVQ improved more with NaP (NNT 7) than PEG (NNT 53). Conclusions: Laxatives do not significantly improve DY or CR in SBCE, but do improve SBQV. The use of laxatives may be beneficial in patients likely to have subtle findings. There are significant differences in methodology/definitions between studies, hence the need for standardized visualization scoring and recording of SBCE findings.