International Journal of Colorectal Disease

, Volume 34, Issue 7, pp 1203–1210 | Cite as

Outpatient facility volume, facility type, and the risk of serious colonoscopy-related adverse events in patients with comorbid conditions: a population-based study

  • Askar ChukmaitovEmail author
  • Bassam Dahman
  • Cathy J. Bradley
Original Article



Patients with a chronic comorbidity or multiple comorbidities are at much greater risk of serious colonoscopy-related gastrointestinal (GI) adverse events relative to patients with no comorbidity. It is important to identify outpatient facilities that can effectively and safely provide colonoscopy to complex patients. To address this need, the association between outpatient facilities’ complex care volume and type (ambulatory surgery center (ASC) and hospital outpatient department (HOPD)) and the risks of serious GI adverse events in colonoscopy patients with single and multiple chronic comorbidities were examined.


Outpatient colonoscopies of 1,020,372 patients with single and multiple comorbidities were investigated, using a retrospective cohort study. Thirty-day hospitalizations due to colonic perforations and GI bleeding were examined. Ambulatory surgery and hospital discharge datasets from California, Florida, and New York for 2006–2009 were used.


Higher complex care volume was associated with lower risks of adverse events in patients with comorbidities (OR 1.69; 95% CI [1.13, 2.54]). ASCs had higher risks of adverse events in patients with comorbidities relative to HOPDs (OR 2.85; 95% CI [2.40, 3.38]). Patients with single and multiple comorbid conditions, patients with systemic diseases, and complex patients of advanced age had higher risks of adverse events.


Referring patients with single and multiple chronic comorbidities to facilities experienced in treating complex patients, or HOPDs, may reduce colonoscopy-related adverse events.


Outpatient colonoscopy Chronic comorbid conditions Adverse events Freestanding ambulatory surgery centers Hospital-based outpatient departments 


Funding sources

The VCU Massey Cancer Center pilot grant (CA016059) was used to purchase the Healthcare Cost and Utilization Project’s (HCUP) datasets for this study. Services in support of the research project were generated by the VCU Massey Cancer Center Biostatistics Shared Resource, supported, in part, with funding from NIH-NCI Cancer Center Support Grant P30 CA016059.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Health Behavior and Policy, School of MedicineVirginia Commonwealth University and VCU Massey Cancer CenterRichmondUSA
  2. 2.Cancer Prevention and ControlColorado School of Public Health and University of Colorado Comprehensive Cancer CenterAuroraUSA

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