A Database Study to Estimate the Risk of Multiple Sclerosis Following Vaccination With Arepanrix™ in Manitoba, Canada

Study Overview
=================
Brief Summary
-----------------
The purpose of this database study is to assess if Arepanrix™ vaccination during the 2009 pandemic was associated with an increased risk of multiple sclerosis (MS) in Manitoba, Canada.

Detailed Description
-----------------
This observational, retrospective, propensity-score matched cohort study using the Manitoba Immunization Monitoring System (MIMS) and the hospital, physician, and prescription claims databases of the Manitoba Health (MH) Database System will assess if Arepanrix™ vaccination during the 2009 pandemic was associated with an increased risk of multiple sclerosis (MS) and other demyelinating conditions not ultimately leading to a multiple sclerosis diagnosis in Manitoba, Canada. The data will be collected form the following linked databases: Manitoba Health (MH) administrative databases Manitoba Immunization Monitoring System (MIMS) Manitoba Health Population Registry (MHPR) Drug Program Information Network (DPIN) Hospital Abstract Database The Medical Services database

Official Title
-----------------
An Observational Retrospective Database Analysis to Estimate the Risk of Multiple Sclerosis Following Vaccination With Arepanrix™ in Manitoba, Canada

Conditions
-----------------
Multiple Sclerosis

Intervention / Treatment
-----------------
* Other: Exposed to Arepanrix™ Cohort
* Other: Unexposed to Arepanrix™ Cohort


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: The entire population of Manitoba is considered for inclusion. Exclusion Criteria: Individuals less than or equal to 6 months of age; Having less than one year of insurance coverage before the enrolment period; Not registered with MH during the enrolment period; Physician or hospitalization records indicating a diagnosis of any demyelinating condition between 1971 (earliest year for which information is available) and the index date.

Ages Eligible for Study
-----------------
Minimum Age: 6 Months

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Exposed to Arepanrix™ Cohort<br>All individuals with Manitoba Immunization Monitoring System (MIMS) record of H1N1 (Arepanrix™) and/or seasonal influenza vaccination during the influenza season 2009/2010 (15 September 2009 to 15 March 2010). | Other: Exposed to Arepanrix™ Cohort<br>* Demographic characteristics such as age, sex, area of residence, socio-economic status; medical history such as comorbidities, immune status, vaccine indication, receipt of other vaccines or medications and frequency of healthcare contacts, as well as information on pregnancy status and pre-existing conditions will be collected..<br>* Other names: Database collection and analysis;|
| Unexposed to Arepanrix™ Cohort<br>All individuals registered with Manitoba Health (MH) during the study period but with no MIMS record for H1N1 (Arepanrix™) and seasonal influenza vaccination during the influenza season 2009/2010 (15 September 2009 to 15 March 2010). | Other: Unexposed to Arepanrix™ Cohort<br>* Demographic characteristics such as age, sex, area of residence, socio-economic status; medical history such as comorbidities, immune status, vaccine indication, receipt of other vaccines or medications and frequency of healthcare contacts, as well as information on pregnancy status and pre-existing conditions will be collected.<br>* Other names: Database collection and analysis;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurrence of MS | During the period of 1 year following administration of Arepanrix™ among an exposed cohort and during an equivalent time period in the unexposed cohort. | 15 September 2009 to 15 March 2010 (up to 6 months) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurrence of MS | From administration of Arepanrix™ until 31 December 2012, among an exposed cohort and during an equivalent time period in the unexposed cohort. | 15 September 2009 to 31 December 2012 (up to 39 months) | 
| Occurrence of demyelinating events which do not ultimately lead to a diagnosis of MS | During the period of 1 year following administration of Arepanrix™ among an exposed cohort and during an equivalent time period in the unexposed cohort. | 15 September 2009 to 15 March 2010 (up to 3 months) | 
| Occurrence of demyelinating events which do not ultimately lead to a diagnosis of MS | From administration of Arepanrix™ until 31 December 2012, among an exposed cohort and during an equivalent time period in the unexposed cohort. | 15 September 2009 to 31 December 2012 (up to 39 months) |