Optimal Placement of Colectomy in the Treatment of Ulcerative Colitis: a Markov Model Analysis

Treatment for moderate-to-severe ulcerative colitis (UC) includes medical therapies such as immunosuppressive agents or surgical options such as colectomy. While prior studies have indicated a mortality benefit with elective surgery, the timing and effectiveness of colectomy in the UC treatment algorithm have not been assessed. We hypothesize that the ideal placement of colectomy occurs prior to the exhaustion of all medical therapies.

We designed a Markov model to assess the ideal position of colectomy. The base case was a 50-year-old male with steroid-dependent moderate-to-severe UC without prior treatment with immunomodulator or biologic therapies. We developed 4 separate algorithms incorporating elective colectomy: (1) prior to biologics, (2) after infliximab monotherapy failure, (3) after infliximab and azathioprine combination therapy failure, and (4) after medically refractory to all medical therapies including vedolizumab. Transition probabilities were obtained from published literature. First-order Monte Carlo simulations of 100 trials of 100,000 individuals were used to calculate quality-adjusted life-year (QALY) estimates. One-way sensitivity analyses were conducted for all variables.

Algorithm 3 (colectomy following combination therapy) was the preferred strategy with 1.864 QALYs (95% CI [1.863, 1.865]) over a 3-year period and the preferred strategy in the probabilistic sensitivity analysis 92.77% of the time.

This simulation suggests that early incorporation of colectomy for patients medically refractory to infliximab and azathioprine combination therapy may yield greater quality of life for patients with steroid-dependent UC. These findings suggest avenues for more patient-centered preference work and a combined medical-surgical approach to UC.