Is Intravenous Bisphosphonate Use Associated with a Higher Risk of a Flare in Inflammatory Bowel Disease Patients? (Bisphosphonates and IBD Flare Risk)

Study type

• Study type:
  Non-interventional study
• Scope of the study:
  Assessment of risk minimisation measure implementation or effectiveness

Non-interventional study

• Non-interventional study design:
  Cohort

Study drug and medical condition

• Anatomical Therapeutic Chemical (ATC) code:
  (M05BA) Bisphosphonates

  Bisphosphonates
• Medical condition to be studied:
  Inflammatory bowel disease

Population studied

• Age groups:
  Adults (18 to < 46 years)

  Adults (46 to < 65 years)
• Estimated number of subjects:
  10000

Study design details

• Main study objective:
  To describe bisphosphonates use patterns among patients with inflammatory bowel disease, and to compare risk of IBD flare between users of intravenous bisphosphonates vs. oral bisphosphonates.
• Outcomes:
  The primary outcomes are surrogate markers of flares of IBD activity, in the 30 days following bisphosphonate use1. IBD-related emergency room visit2. IBD-related hospitalization3. Systemic corticosteroid or enteral budesonide prescription in those who were not treated with corticosteroids in the 30 day period before the index date
• Data analysis plan:
  Analysis1. After identifying the IBD Cohort, we will compare the demographics, such as age, sex, geographic location and Charlson co-morbidity index, as well as available disease related variables, such as type of IBD, medications used in the 90 days prior to bisphosphonate use, IBD related hospitalizations, surgery and health care utilization of IBD patients using IV versus oral bisphosphonates2. We will construct a propensity score model to compare IBD patients receiving IV bisphosphonates to those receiving oral bisphosphonates. We will implement standardized mortality ratio (SMR) weighting using estimated propensity scores to achieve covariate balance between the IV and oral bisphosphonate cohorts, to control for measured confounding. The estimand of interest will be the average treatment effect among the treated (IV bisphosphonates users).3. We will compare the crude and adjusted 30-day incidence of outcomes in the IV bisphosphonate group and oral bisphosphonate group.