Is Elderly Age a Simple Predictive Factor for Inadequate Bowel Preparation before Colonoscopy?

Bowel preparation is important when visualizing the whole colonic mucosa and greatly influences the rate of adenoma detection, which is considered to be a standard indicator of successful colonoscopy. 1 The target level of adequate preparation (so that repeat colonoscopy is not required within ≤1 year) is 85% as recommended by the American Society for Gastrointestinal Endoscopy (ASGE)/the American College of Gastroenterology task force. 1 In recent studies, the bowel preparation rates have reached this target, and low-volume products that effectively cleanse the colon are now available. 2 However, the bowel preparation rate often fails to meet the expected level in real clinical practice. According to the Clinical Outcomes Research Initiative's national endoscopic database in the United States, preparation was adequate in only 76.9% of patients. 3 Inadequate bowel preparation is associated with many negative factors in terms of colorectal cancer screening, such as incomplete colonoscopy, a lower adenoma detection rate, an increased procedure time, an increased chance of adverse events, and increased medical costs because short-term repeat colonos-copy is needed. 4 Factors contributing to inadequate bowel preparation have been identified in a number of previous studies. 5 Well-known factors are medical conditions that affect bowel motility including chronic constipation, liver cirrhosis, diabetes, previous intra-abdominal surgery, use of multiple medications, use of opioids or tricyclic antidepressants, and conditions associated with immobilization such as older age, poor physical status, obesity, neurological disease, and hospitalization. 5 In particular, age has been shown to be an independent risk factor for poor bowel preparation regardless of the type of preparation. 5-7 Recently, the number of colonoscopies performed in elderly and very elderly patients has increased, caused by the global increase in life expectancy. Colonoscopies in elderly examinees are frequently incomplete and carry greater risk of procedural complications. In a recent meta-analysis of colo-noscopies in elderly patients, inadequate bowel preparation was documented in 18.8% of patients >65 years of age, and in 12.1% of those >80 years. 8 However, some studies have shown different results. In prospective studies comparing the success rates and yields of colonoscopy in the elderly with those in younger patients, there were no significant differences in rates of poor Possible explanations for poor bowel preparation in the elderly include delayed gastrointestinal motility, a high rate of constipation, poor compliance, poor understanding of preparation instructions, a high number of previous operations, a high frequency of comorbid diseases (such as diabetes), and other …