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

Study Overview
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Brief Summary
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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.

Official Title
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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

Conditions
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Prevention of Oesophagus Cancer and Stomach Cancer

Intervention / Treatment
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* Drug: Acetylsalicylic Acid(BAYE4465, Aspirin )


Participation Criteria
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Eligibility Criteria
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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

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 89 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Low-dose ASA cohort<br>A person is identified as newly exposed to low-dose ASA, he/she will become member of new user low-dose ASA cohort and that date will be the start date for outcome follow-up. | Drug: Acetylsalicylic Acid(BAYE4465, Aspirin )<br>* Administration according to clinical practice<br>|
| Comparison unexposed cohort<br>When a member of new user low-dose ASA cohort is confirmed, one comparison member will be confirmed also from the source population not yet censored on that day (start date) and with the same distribution of matching factors (age, sex, time interval since entry date and number of PCP visits in the year prior to start date) of its low-dose ASA pair with the only difference of being free of ASA on start date. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence rates of oesophageal cancer and stomach cancer with use of low-dose ASA overall compared to non-use | Diagnosis of cancer is routinely recorded by means of Read codes in THIN database | Retrospective analysis between 1-Jan-2005 and 31-Dec-2017 | 
| Incidence rates of oesophageal cancer and stomach cancer with use of low-dose ASA by age compared to non-use | Age: 40-64 years, 65-74 years and 75 and more years. | Retrospective analysis between 1-Jan-2005 and 31-Dec-2017 | 
| Incidence rates of oesophageal cancer and stomach cancer with use of low-dose ASA by sex-specific compared to non-use | Sex: Male, Female | Retrospective analysis between 1-Jan-2005 and 31-Dec-2017 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of oesophageal cancer and stomach cancer among new users of low-dose ASA |  | Retrospective analysis between 1-Jan-2005 and 31-Dec-2017 | 
| Duration of low-dose ASA | Duration of treatment will be calculated among current users. | Retrospective analysis between 1-Jan-2005 and 31-Dec-2017 | 
| Dose-response of low-dose ASA | The following daily doses will be ascertained: 75 mg, 150 mg and 300 mg. | Retrospective analysis between 1-Jan-2005 and 31-Dec-2017 | 
| Number of case-fatality of oesophageal cancer and stomach cancer among new users of low-dose ASA |  | Retrospective analysis between 1-Jan-2005 and 31-Dec-2017 | 
| Incidence of oesophageal cancer and stomach cancer among new users of low-dose ASA for primary or secondary cardiovascular prevention | The primary and secondary cardiovascular prevention population of low-dose ASA users will be defined using a computer algorithm ascertaining any recorded Read code suggestive of cardiovascular disease (CVD). | Retrospective analysis between 1-Jan-2005 and 31-Dec-2017 |