FACTORS AFFECTING THE QUALITY OF BOWEL PREPARATION FOR COLONOSCOPY IN THE ELDERLY: A RETROSPECTIVE ANALYSIS OF A PROSPECTIVE COHORT

Aims This study aimed to assess the difference in bowel cleansing in the elderly compared to younger patients and to evaluate independent factors of cleansing success.

Methods We retrospectively reviewed a prospective cohort of 1289 in- and out-patients performing a colonoscopy after a 1, 2, or 4L PEG-based preparation. The elderly population was defined by an age ≥65 years. Bowel cleansing was assessed through the Boston Bowel Preparation Scale (BBPS), cleansing success was defined as a total BBPS≥6 with a partial BBPS≥2 in each segment.

Results All 1289 patients were included in the analysis, among these, 44.6% were ≥65 years. Compared to patients < 65 years, patients ≥65 years achieved a lower cleansing success rate both overall, both in the afternoon-only and afternoon-morning preparation subgroups: 70.3 vs 77.3% (p= 0.04), 61.2% vs 69.5% (p=0.01) and 84.9% vs 90.2% (p=0.07) respectively. At multivariate analysis, split regimen (OR=2.49, 95%CI=1.38-4.48; p=0.002), adequate cleansing at previous colonoscopy (OR=3.28, 95%CI=1.40-7.68; p=0.006) and tolerability (OR=1.14, 95%CI=1.03-1.26; p=0.006) were independently associated with a cleansing success in the group of patients aged < 65 years. In the group of elderly, split regimen (OR=2.43, 95%CI=1.34-4.38; p=0.003), adequate cleansing at previous colonoscopy (OR=2.29, 95%CI=1.14-4.73; p=0.02), tolerability (OR=1.29, 95% CI=1.16-1.44; p< 0.001), low-fiber diet for at least 3 days (OR= 2.45, 95%CI=1.42-4.24; p=0.001) and colonoscopy within 5 hours after preparation (OR= 2.67, 95%CI=1.28-5.56; p=0.008) were independently associated with a cleansing success.

Conclusions Compared to younger patients, adequate cleansing in the elderly is influenced by a greater number of factors. Among these, split regimen, colonoscopy within 5 hours after the end of preparation, low-fiber diet for at least three days, adequate cleansing at previous colonoscopy and tolerability were independently associated with a cleansing success. These factors play a crucial role and need to be properly addressed to optimize the quality of bowel preparation in the elderly.