EffectiveNess of Low-dose Aspirin in Prevention of Cancer in the Stomach and Oesophagus (GastrointEstinal Cancer Prevention) - United Kingdom ("ENgAGE - UK"): Study to Evaluate the Risk of Cancer in the Stomach and Oesophagus Among New Users of Low-dose Aspirin Using the THIN Database in the UK

Effectiveness of Low-dose Aspirin in Gastrointestinal Cancer Prevention -United Kingdom ("ENgAGE - UK"): A Cohort Study on the Risk of Gastric and Oesophageal Cancer Among New Users of Low-dose Aspirin Using the THIN Database in the UK

Researchers already did studies in low-dose Aspirin for the prevention of heart and blood vessels disease and for the prevention of cancer of the colorectum. In this study, they want to learn whether an effect for the prevention of oesophagus cancer and stomach cancer goes along with the use of low-dose ASA on patients taking this medicine for the prevention of heart and blood vessels disease compared to non-use. To find this out electronic medical records stored in primary care database in the UK, The Health Improvement Network (THIN), will be used.

Inclusion Criteria:

• Aged 40-89 years
• Enrolled with the PCP for at least 2 years
• To have a history of computerized prescriptions in THIN for at least 1 year prior to start date

Exclusion Criteria:

• To be exposed to low-dose ASA before entering in the study
• Having a diagnosis of any cancer before entering in the study