Oral sulfate-based versus low-volume polyethylene glycol-ascorbate regimens for colonoscopy preparation in the geriatric population: a systematic review and meta-analysis of randomized controlled trials

Background/Aims: Adequate bowel preparation is essential for high-quality colonoscopy; however, older adults often struggle with large-volume regimens. Low-volume oral sulfate (OS)-based and polyethylene glycol-ascorbate (PEG-Asc) may improve tolerability without compromising efficacy. This study compared the efficacy, tolerability, and safety of these regimens in older adults.Methods: We searched the PubMed, Embase, and Cochrane databases from inception until May 2025 for randomized controlled trials comparing OS with low-volume PEG-Asc in adults aged ≥65 years. Outcomes were pooled using random-effects models as risk ratios (RRs) or mean differences (MDs).Results: Six trials (n=682; OS, 340; PEG-Asc, 342) were included. The overall cleansing success rates were comparable (RR, 1.00; 95% confidence interval [CI], 0.96–1.03). Total Boston bowel preparation scale and segmental scores did not significantly differ between the groups (MD, 0.08; 95% CI, −0.10 to 0.27). OS improved lesion detection in terms of polyp detection (RR, 1.21; 95% CI, 1.01–1.45) and adenoma detection rates (RR, 1.28; 95% CI, 1.10–1.49). Patient-reported satisfaction modestly favored OS compared with PEG-Asc (MD, 0.69; 95% CI, 0.10–1.29), whereas willingness to reuse was similar between the two groups (RR, 1.09; 95% CI, 0.97–1.23). Adverse events and procedural metrics did not significantly differ between the groups.Conclusions: In adults aged ≥65 years, OS and low-volume PEG-Asc achieved similar cleansing quality and safety. OS may confer higher polyp and adenoma detection rates than PEG-Asc and may be a reasonable option for maximizing lesion detection.