After Public Drug Coverage for Infliximab, Adalimumab, Surgeries and ED Visits for CD Fell

A recent study examined whether patients with Crohn disease (CD) using infliximab or adalimumab had fewer hospitalizations, surgeries, and emergency department (ED) visits after the drugs began to get public coverage in Ontario, Canada.

In contrast to a somewhat similar study that had more mixed results, the present study found that as the rates of those using infliximab and adalimumab rose, hospitalizations, emergency department visits, and inpatient surgeries declined.

Despite the use of immunosuppressive medications, many patients may still suffer disease‐related complications, and the lifetime risk of surgery remains high, estimated cumulatively at 60% to 80%, with the greatest risk in the first 5 years after diagnosis, according to the authors.

Public drug coverage for biologic therapy for adult patients with CD did not occur until 2004, when the Ontario Drug Benefit began coverage for infliximab for those who qualified financially if they were under age 65 or for patients 65 or older. Adalimumab coverage began in 2007.

This population‐based cohort study included 45,235 patients in the Ontario Crohn's and Colitis Cohort (OCCC) from April 2003 to March 2014 The OCCC is a patient‐derived cohort to identify patients with CD, ulcerative colitis (UC), or other inflammatory bowel disease (IBD); patients were classified as having CD or UC based on the diagnosis that was recorded in the majority of the last 9 IBD visits.

Patients aged 65 years or older at the time of diagnosis required the addition of at least 1 prescription claim for an IBD‐specific medication.

The outcomes were tied to those patients having CD, and a Poisson probability distribution model was used to test for trends in the rates of the specific outcomes over time.

Between 2003 to 2014, patients received public drug benefits for infliximab or adalimumab at a combined rate of 2.2% in 2003, rising to 18.8% of eligible patients by 2014.

During that period, the prevalence of CD&#8208;related hospitalizations fell 32.4% from 154 per 1000 population (95% CI, 150-159) to 104 per 1000 population (95% CI, 101-107; P <.001). In addition, there was a 39.6% decline in inpatient surgeries (mostly bowel resections) from 53 per 1000 (95% CI, 50-55) to 32 per 1000 (95% CI, 30-34; P <.001).

However, outpatient surgeries rose from 8 per 1000 (95% CI, 7-9 to 12 per 1000 (95% CI, 10-13; P <.001). Outpatient surgeries were largely related to fistulas, perianal disease, and stricture.

CD&#8208;related ED visits fell 28.4% from 141 per 1000 (95% CI, 137-146) to 101 per 1000 (95% CI, 99-104) from 2003 to 2014 (P <.001).

Hospitalizations may be viewed as a marker of efficacy of medication treatment, the authors noted. During the time period of the study, treatment of CD shifted from corticosteroids and thiopurines to biologics for high-risk patients, they said.

Discussing the results, the researchers noted that the outpatient surgeries were less invasive procedures related to the management of perianal disease and dilations of the small or large bowel, which are less likely to be responsive to tumor necrosis factor antagonists, or indeed other biological treatments, than luminal CD.

A similar study published earlier this year found that infliximab for the treatment of CD and UC did not result in lower population rates of hospitalizations or intestinal surgeries.

Reference

Rahman A, Jairath V, Feagan BG, et al. Declining hospitalisation and surgical intervention rates in patients with Crohn's disease: a population&#8208;based cohort. Aliment Pharmacol Ther. 2019;50:1086-1093. doi: 10.1111/apt.15511.