Epidemiological Study on the Safety of Aspirin in The Health Improvement Network (THIN)

A Pharmacoepidemiological Study on the Risk of Bleeding in New Users of Low-dose Aspirin (ASA) in The Health Improvement Network (THIN), UK

To investigate the risk of major bleeding (including gastrointestinal and intracranial bleeding episodes) among new users of low-dose acetylsalicylic acid (ASA) in clinical practice

These will be based on population-based cohorts using data from a primary care database in the UK: The Health Improvement Network (THIN) and will serve to make a clinically meaningful benefit-risk assessment regarding major bleeding consequences of ASA exposure in general population.

Inclusion Criteria:

• Aged 40-84 years
• Enrolled with the Primary Care Physician (PCP) for at least 2 years,
• To have a history of computerized prescriptions for at least 1 year prior
• To have at least one encounter/visit recorded in the last three years

Exclusion Criteria:

• To be exposed to low dose ASA before entering in the study
• Having a diagnosis of cancer before entering in the study
• Having a diagnosis of alcohol abuse before entering in the study
• Having a diagnosis of coagulopathies before entering in the study
• Having a diagnosis of esophageal varices before entering in the study
• Having a diagnosis of chronic liver disease before entering in the study