Danish Cohort Study on Warfarin-Statin Drug Interactions, 2000-2015

A 2000-2015 register-based cohort study from Denmark evaluated the drug-drug interaction between warfarin and statins. The study, conducted by Anna Elise Engell of Hvidovre Hospital, linked INR measurements and prescription data for 1,551 warfarin users initiating simvastatin, atorvastatin, or rosuvastatin. It found minor INR increases, with simvastatin initiation raising mean INR from 2.40 to 2.71.

Use Cases

• Modeling the effect of statin initiation on INR levels based on prescription and measurement linkage.
• Comparing the interaction magnitude between different statin types (simvastatin, atorvastatin, rosuvastatin).
• Assessing the clinical relevance of minor INR changes in warfarin therapy management.
• Validating pharmacovigilance signals using longitudinal prescription and laboratory data.

Strengths

• Study period spans 15 years (2000-2015), providing longitudinal context.
• Specific cohort sizes are provided (e.g., n=1,363 for simvastatin).
• Results include precise effect estimates with confidence intervals (e.g., mean change 0.32, 95%CI 0.25-0.38).

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count for the full linked dataset is unknown, which may limit suitability assessment.
• Data may reflect geographic bias inherent to the Danish national register data.

Provenance

Source

Hvidovre Hospital

Collection Method

Register-based cohort study linking national data on INR measurements and filled prescriptions.

Time Range

2000-2015

Geography

Denmark