Factors associated with inadequate colorectal cancer screening with flexible sigmoidoscopy

Abstract

Background and study aim Inadequate colorectal cancer screening wastes limited endoscopic resources. We examined patients factors associated with inadequate flexible sigmoidoscopy (FSG) screening at baseline screening and repeat screening 3–5 years later in 10 geographically-dispersed screening centers participating in the ongoing Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial Methods A total of 64,554 participants (aged 55 – 74) completed baseline questionnaires and underwent FSG at baseline. Of these, 39,385 participants returned for repeat screening. We used logistic regression models to assess factors that are associated with inadequate FSG (defined as a study in which the depth of insertion of FSG was <50 cm or visual inspection was limited to <90% of the mucosal surface but without detection of a polyp or mass). Results Of 7,084 (11%) participants with inadequate FSG at baseline, 6,496 (91.7%) had <50 cm depth of insertion (75.3% due to patient discomfort) and 500 (7.1%) participants had adequate depth of insertion but suboptimal bowel preparation. Compared to 55–59 year age group, advancing age in 5-year increments (odds ratios (OR) from 1.08 to 1.51) and female sex (OR = 2.40; 95% confidence interval (CI): 2.27 – 2.54) were associated with inadequate FSG. Obesity (BMI >30 kg/m2) was associated with reduced odds (OR = 0.67; 95%CI: 0.62 – 0.72). Inadequate FSG screening at baseline was associated with inadequate FSG at repeat screening (OR = 6.24; 95%CI: 5.78 – 6.75). Conclusions Sedation should be considered for patients with inadequate FSG or an alternative colorectal cancer screening method should be recommended.

Alternatives to colonoscopy for population-wide colorectal cancer screening

“…71 Most studies were in individuals aged ≥50 [70][71][72] or ≥55 years. 68,69,73 The sensitivity of FS depends on the adequacy of mucosal inspection and is operator-dependent. 73 Studies have shown inadequate screening in up to 91.7% of cases, ie <50 cm depth of insertion.…”

“…68,69,73 The sensitivity of FS depends on the adequacy of mucosal inspection and is operator-dependent. 73 Studies have shown inadequate screening in up to 91.7% of cases, ie <50 cm depth of insertion. 73 The technique had relatively low and fluctuating participation rates (20.9%-63.0%).…”

“…73 Studies have shown inadequate screening in up to 91.7% of cases, ie <50 cm depth of insertion. 73 The technique had relatively low and fluctuating participation rates (20.9%-63.0%). 70,71 A 35.3% decrease in adherence from baseline to subsequent study was observed.…”

Concerns and challenges in flexible sigmoidoscopy screening

“…Black study subjects, unmarried persons and those with less than a high school education were less likely to return for repeat examinations [59]. Those with inadequate FS at baseline were also less likely to return for a repeat examination when compared with those with adequate baseline FS (65.3 vs 81.6%; p < 0.001) [60]. …”

“…These patients are usually rescheduled for a repeat examination in usual clinical practice. Factors that have been identified as associated with an increased risk of inadequate FS include advancing age, female sex and cigarette smoking, but obesity was associated with a reduced risk [60-62]. Inadequate FS dampens the enthusiasm of patients for further endoscopic screening.…”