Title
DARWIN EU® – Drug Utilisation Study of prescription opioids.
Rationale and Background
Prescription opioids, while effective for managing severe pain, have led to a public health crisis due to misuse, addiction, and overdose, particularly in the US. Recently, concerns have been growing in Europe due to increasing opioid use and related mortality. Factors such as chronic pain, mental health disorders, and advanced age can exacerbate misuse and the development of dependence. Given the potential for global spread of this issue, enhanced surveillance and in-depth research into opioid utilisation patterns are imperative. A drug utilisation study using a Common Data Model (CDM) is a promising approach to supplement European opioid monitoring systems, providing more granular data to inform evidence-based decisions on this complex topic.
Research question and Objectives
The objectives of this study are
i To investigate the annual incidence and annual period prevalence of use of opioids (overall, active drug substance, strength (weak/strong opioids) and route (oral, transdermal or parenteral), stratified by history of cancer/no history of cancer and for calendar year, age, sex and country/database during the study period. (ii) To determine duration of prescription opioid use, as well as characteristics of new users and indication for opioid prescribing/dispensing overall and in people with history of cancer/no history of cancer, all stratified by calendar year and country/database.
Research Methods
Study design
• Population level cohort study (Objective 1, Population-level drug utilisation study on opioids)
• New drug user cohort study (Objective 2, Patient-level drug utilisation analyses regarding summary characterisation, duration, and indication of opioid use)
Population
Population-level utilisation of opioids: All people registered in the respective databases on 1st of January of each year in the period 2012-2024 (or the latest available, whatever comes first), with at least 1 year of prior data availability, will participate in the population-level analysis (period prevalence calculation in Objective
MODEL DE SOL·LICITUD
2 IMP-126-CT Versió 07
1). Therefore, children aged <1 year will be excluded.
New users of opioids in the period between 1/1/2012 and 31/12/2024 (or latest date available, whatever comes first), with at least 1 year of data availability, and no use of the respective opioid in the previous 12 months, will be included for incidence rate calculations in Objective 1.
Patient-level drug utilisation: New users of opioids in the period between 1/1/2012 and 31/12/2024 (or latest date available, whatever comes first), with at least 1 year of data availability, and no use of the respective opioid in the previous 12 months, will be included for patient-level drug utilisation analyses.
Variables
Drug of interest: Opioids (substances listed in ATC classes N01AH, N02A and R05DA); naloxone; and fixed naloxone-opioid combinations.
Data sources
1. Estonian Biobank (EBB), Estonia
2. IQVIA LBD Belgium, Belgium
3. Integrated Primary Care Information Project (IPCI), The Netherlands
4. The Information System for Research in Primary Care (SIDIAP), Spain
5. Clinical Data Warehouse for Bordeaux University Hospital (CDWBORDEAUX), France
6. Danish Data Health Registries (DK-DHR), Denmark
7. Institut Municipal Assistència Sanitària Information System (IMASIS), Spain
8. Norwegian Linked Health Registry (NLHR), Norway
Sample size
No sample size has been calculated.
Data analyses
Population-level drug utilisation will be conducted in all databases. Patient-level DUS analyses will be conducted in all databases. No duration will be calculated for EBB.
Population-level opioid use: Annual period prevalence of opioid use and annual incidence rates per 100,000 person years will be estimated.
Patient-level opioid use: Summary patient-level characterisation by list of pre-defined conditions/medications of interest will be conducted at index date, including patient demographics, and history of comorbidities and comedication. Frequency of indication at index date, and in the immediate time before will be calculated. Cumulative treatment duration will be estimated for the first treatment era and the minimum, p25, median, p75, and maximum will be provided.
For all analyses a minimum cell count of 5 will be used when reporting results, with any smaller counts will be noted as <5.