Inpatient Constipation Among Migraine Patients Treated With Preventive Medications: A Retrospective Cohort Study in a United States Electronic Health Record Database

Study type

• Study topic:
  Human medicinal product

  Disease /health condition
• Study type:
  Non-interventional study
• Scope of the study:
  Assessment of risk minimisation measure implementation or effectiveness
• Data collection methods:
  Secondary use of data

Non-interventional study

• Non-interventional study design:
  Cohort

Study drug and medical condition

• Name of medicine:
  AIMOVIG
• Medical condition to be studied:
  Migraine

Population studied

• Short description of the study population:
  The study population will be drawn from Optum’s EHR database, a de-identified patient-level database that integrates multiple electronic medical record (EMR) data systems with medical claims, prescription, and practice management data.; Study Period; Study cohort members will be identified from 17 May 2018, which is the date of US FDA approval for erenumab, through 31 March 2020. Outcomes will be identified through 31 March 2020.; Inclusion Criteria; Initiators of erenumab, other CGRP antagonists, and SOC preventive medications will be identified during the cohort accrual period using NDCs as recorded in the prescription order table within the EHR database. SOC preventive medications will include select antiepileptic migraine preventive agents. A list of these SOC antiepileptic preventive medications is provided in Section 8.3.1. To select initiator cohorts, only the first prescription order for these medications that are identified during the study period will be assessed for the following criteria: ; • At least 18 years of age on the prescription order date ; • At least two diagnosis codes for migraine (ICD-10-CM G43.-) on two different days in the 12 months prior to and including the prescription order date, or at least one prescription order for an acute migraine treatment (triptan or ergot) and at least one diagnosis code for migraine in the 12 months prior to and including the prescription order date ; • All cohorts will be required to have at least one outpatient clinical visit at least one year prior to the prescription order date to establish a 12-month baseline period for assessment of prevalent medication use, patient characteristics, and comorbidities. If sample size is a concern, we will also examine the number of patients who have a visit at least 6 and 9 months prior to their prescription order date. ; • No prescription order for any CGRP antagonist during the 12-month baseline period. ; • For the SOC antiepileptic preventive medication cohort only, no prescription order for any of the five antiepileptic medications during the 12-month baseline period. ; The index date will be defined as the date of the earliest prescription order that meets all of the above criteria. Because it is expected that patients will have started erenumab or another CGRP antagonist after attempting treatment with an SOC preventive medication, the SOC antiepileptic preventive medication cohort will be selected from the remaining population of migraine preventive treatment users after the erenumab and CGRP antagonist cohorts are formed. Random sampling may be considered for the SOC antiepileptic preventive medication cohort if the sample size following implementation of the inclusion criteria is much larger than the size of the erenumab and the other CGRP antagonist cohorts.; Exclusion Criteria; Cohort members with missing or conflicting age or sex information will be excluded.
• Age groups:
  Adults (18 to < 46 years)

  Adults (46 to < 65 years)

  Adults (65 to < 75 years)

  Adults (75 to < 85 years)

  Adults (85 years and over)
• Special population of interest:
  Other
• Special population of interest, other:
  Migraine patients
• Estimated number of subjects:
  114828

Study design details

• Main study objective:
  This retrospective observational study will estimate and compare the incidence proportion of inpatient constipation among migraine patients treated with erenumab, other monoclonal antibodies targeting the CGRP pathway, and SOC antiepileptic preventive medications, to give context to events observed in real-world observations from post-marketing surveillance data.
• Outcomes:
  Describe baseline characteristics, estimate the incidence proportion of inpatient constipation, assess the comparability of patients treated with erenumab to patients treated with other CGRP antagonists and to patients treated with SOC antiepileptic preventive medications, and, if appropriate, compare the incidence proportion of inpatient constipation across the three cohorts.
• Data analysis plan:
  Data analyses will include a summary of baseline characteristics and risk factors for constipation, propensity score (PS) matching of the erenumab initiator cohort to the other CGRP antagonists and, separately, to the SOC antiepileptic preventive medication initiator cohorts, and an assessment of the comparability of the matched cohorts with respect to baseline patient characteristics. The incidence proportion of inpatient constipation and corresponding 95% CIs will be estimated within each cohort. If appropriate, the odds ratio and corresponding 95% confidence intervals will be used to compare the incidence proportion of inpatient constipation across cohorts.

Documents

Study results

20190501_Observational Research Study Report Published Report_Abstract_Redacted