Background
A proportion of patients with initial presentation of ulcerative proctitis (UP) progress to more extensive colitis. We sought to characterize the natural history and identify clinical predictors of extension in UP.
Methods
We performed a retrospective cohort study of participants with a new diagnosis of UP from January 2000 to December 2015. We used cox proportional hazard modeling to identify predictors of disease extension.
Results
Through December of 2015, we identified 169 cases of UP with a median age of diagnosis of 40 years (range: 16–91 years) and a median follow up of 4.3 years (range: 3.3–15.1 years). 53 (31%) patients developed extension over the follow up time. Compared to non-extenders, the need for immunosuppressive or biologic therapy was significantly higher among extenders (34% vs. 2.6%, p < 0.001). In multivariable analyses, compared to UP cases with BMI < 25, the adjusted hazard ratios (aHRs) of extension were 1.75 (95% CI, 0.95 – 3.23) and 2.77 (95% CI, 1.07 – 7.14) among overweight and obese patients, respectively (Ptrend = 0.03). Similarly, patients with a history of appendectomy or endoscopic finding of moderate to severe disease had a higher risk of extension (aHR = 2.74, 95% CI 1.07 – 7.01 and 1.96, 95% CI 1.05–3.67, respectively).
Conclusion
In a retrospective cohort study, we show that appendectomy, BMI, and endoscopic activity at the time of diagnosis of proctitis are associated with increased risk of extension. In addition, our data suggest that extenders are more likely to require immunosuppressive or biologic therapy.