SARS-CoV-2 Impact on Screening Colonoscopy: Implications for Postpandemic Recovery.

Coronavirus disease 2019 (COVID-19) (1) has disrupted many elective procedures including screening colonoscopy (2). We have tried to quantify the magnitude of the backlog created and time required to resolve it. As COVID-19 cases increase everywhere in the country besides New York, our backlog estimates are likely to be reflected nationwide.

To estimate backlog, we used historical monthly screening colonoscopy data for 14 hospitals and 1 ASC from January 2016 to May 2020, within a large health system in the New York metropolitan area which was heavily burdened by the COVID pandemic (3). To estimate the number of screening colonoscopies performed each month in setting of the pandemic, we used a previously described triphasic sigmoidal recovery model (4). The first phase of the model was the shutdown phase, from March to May 2020, when elective procedures were halted. Second was the ramp-up phase, starting June 2020, when our health system started to increase its procedural volume. We modeled this using a Monte Carlo simulation of a Gompertz function, which is a sigmoidal growth function that has been used to analyze recovery after ecological disaster phenomenon (5). We assumed optimistic and pessimistic ramp-up scenarios, with growth constants of 0.9 and 0.5, respectively, arbitrarily chosen, since it is impossible to predict actual ramp-up velocity given unprecedented magnitude of procedural disruption. Third was the plateau phase where we assumed that the colonoscopy volume would revert to baseline expected case volumes at some future time. We simulated the time it would take to catch up on backlog if we increased throughput by 10%–30%/month after reaching reference monthly volume. We also sought to simulate the impact of future patient demand reduction (in case of a second COVID-19 wave, or future procedural suspensions) on backlog by simulating future patient referral (procedural demand) reduction by 10%.

Before the pandemic, in our health system, we performed 291 screening colonoscopies in January 2020 (used as reference volume for comparison). This was consistent with the monthly average for 2019, which was 295 cases/month. Based on a Monte Carlo simulation, it would take up to 4 or 6 months under the optimistic and pessimistic scenarios, respectively, to reach the reference monthly colonoscopy volume (Figure 1).

Figure 1.

Monte Carlo simulation analysis of screening colonoscopies per month in a large health system in the United States. The green curve represents the optimistic ramp-up scenario, and the red curve represents the pessimistic ramp-up scenario.

By June 2021, cumulative colonoscopy backlog would reach 3.0-months-worth of January 2020 cases (871 cases) under the optimistic scenario and 4.3-months-worth (1,247 cases) under the pessimistic scenario. A decline in patient referrals (procedural demand) by 10% in the long run in response to persistent COVID-19 effects would result in a backlog of 1.7-months-worth under the optimistic ramp-up scenario and 3.0-months-worth under the pessimistic scenario by June 2021. Under the optimistic scenario, if production was increased by 10%/month starting September 2020, it would take 27 months to catch up on backlog, and if production increased by 30%/month, it would take 9 months to catch up on the backlog.

Our data show the pandemic has created 3–4 months backlog of screening colonoscopies. Catch-up period for procedural backlog could vary anywhere from 1–2 years. We show how the COVID-19 pandemic affects screening colonoscopy volume and highlights the need to plan appropriate mitigation strategies.

CONFLICTS OF INTEREST

Guarantor of the article: Aakash Aggarwal, MD.

Specific author contributions: Study conception and design: A.A. and A.J.; acquisition of data: A.J.T.; analysis and interpretation of data: A.A., A.J., and P.J.; drafting of manuscript: A.A., A.J., and M.S.; critical revision: A.J.T. and P.C.B.; final approval: A.A., A.J., P.J., M.S., P.C.B., and A.J.T.

Financial support: None to report.

Potential competing interests: A.J.T.—Consultant to Olympus America and Pentax Medical, Research Support to Ninepoint Medical. P.C.B.—Consultant to Olympus America, Boston Scientific, Fujifilm, and Apollo Endosurgery. A.J.—Consultant to Stryker Spine, DePuy Spine.