The incidence of and risk factors for inadequate bowel preparation in elderly patients: A prospective observational study

BACKGROUND/AIM: We conducted a prospective observational study to identify the incidence of and risk factors for inadequate bowel preparation in elderly Chinese patients. PATIENTS AND METHODS: We enrolled 240 outpatients over 60 years of age scheduled for elective colonoscopy at our university hospital between November 2016 and April 2017. We recorded patient demographics, bowel preparation data, and clinical characteristics. Factors associated with inadequate bowel preparation were identified by multivariate logistical regression analysis. RESULTS: The rate of inadequate bowel preparation was 34.6%. Factors associated with inadequate bowel preparation were a history of abdominal surgery (OR, 2.617; CI, 1.324–5.174; P = 0.006), chronic constipation (OR, 3.307; CI, 1.551–7.054; P = 0.002), non-compliance with dietary instructions (OR, 2.239; CI, 1.122–4.471; P = 0.022), non-compliance with polyethylene glycol (PEG) dosage (OR, 4.576; CI, 1.855–11.287; P = 0.001), walking <30 minutes during preparation (OR, 2.474; CI, 1.261–4.855; P = 0.008), interval between PEG ingestion and the onset of bowel activity (OR, 1.025; CI, 1.010–1.040; P = 0.001), and a last stool that was not clear and watery (OR, 4.191; CI, 1.529–11.485; P = 0.005). CONCLUSION: The incidence of adequate bowel preparation in elderly patients is not optimal. Walking <30 minutes during the PEG ingestion period may be a surrogate for bowel preparation failure. Future studies should identify elderly patients at risk for poor bowel preparation and develop interventions to improve outcomes in this population.