Socioeconomic and other predictors of colonoscopy preparation quality

Suboptimal bowel preparation prior to colonoscopy is a common occurrence, with a deleterious impact on colonoscopy effectiveness. Established risk factors for suboptimal bowel preparation have been proposed, but social factors, such as socioeconomic status and marital status, have not been investigated.

The aim of this study was to evaluate sociodemographic factors, including insurance status and marital status, as predictive of suboptimal preparation.

We analyzed a database of 12,430 consecutive colonoscopies during a 28-month period at Columbia University Medical Center. We collected the following variables: age, gender, indication for colonoscopy, location (inpatient vs. outpatient), race, marital status, and Medicaid status. Preparation quality was recorded and dichotomized as optimal or suboptimal. We employed multivariate regression to determine independent risk factors for suboptimal bowel preparation.

Among the 10,921 examinations in which bowel preparation was recorded, suboptimal preparation occurred in 34% of Medicaid patients versus 18% of non-Medicaid patients (P < 0.0001); this remained significant in the multivariate analysis (odds ratio (OR) 1.84, 95% CI 1.61-2.11). Married patients had decreased rates of suboptimal preparation (OR 0.89, 95% CI 0.80-0.98). Other variables associated with suboptimal preparation included increased age (OR per 10 years 1.09, 95% CI 1.05-1.14), male gender (OR 1.44, 95% CI 1.31-1.59), inpatient status (OR 1.51, 95% CI 1.26-1.80), and later time of day (OR 1.89, 95% CI 1.71-2.09).

Unmarried status and Medicaid status are predictive of suboptimal bowel preparation. Future studies are warranted to identify how these social conditions predict bowel preparation quality and to implement interventions to optimize bowel preparation in vulnerable populations.