EffectiveNess of Low Dose Aspirin in GastrointEstinal Cancer Prevention - Taiwan

Study Overview
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Brief Summary
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The study evaluates the protective effect of low-dose aspirin use on gastrointestinal cancers (colorectal, esophageal and gastric cancers) in long-term users, episodic users and non-users of aspirin in Taiwan.

Detailed Description
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The primary objective is to investigate the protective effect of long-term low dose use of aspirin on colorectal, esophageal and gastric cancer in adult subjects from Taiwan. Secondary objectives are to evaluate the protective effect by duration of low-dose aspirin use on colorectal cancer, the effect of discontinuation of aspirin on colorectal cancer prevention, the staging distribution of colorectal cancer and the description of fatal cases due to colorectal cancer. Aspirin use will be identified through Taiwanese National Health Insurance (NIH) data from 2000 to 2015. Cancer cases and staging of the three cancer types will be ascertained through the Taiwan Cancer Registry, using data from 2000 to 2014. Fatal cases will be ascertained using Mortality database from 2000 to 2015.

Official Title
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EffectiveNess of Low Dose Aspirin in GastrointEstinal Cancer Prevention - Taiwan

Conditions
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Colorectal Neoplasms

Intervention / Treatment
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* Drug: Aspirin (Acetylsalicylic Acid, BAYE4465)
* Other: No drug


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 40 or older at the cohort entry date. Taiwanese National Health Insurance enrollees with non-missing and consistent age and gender information. Exclusion Criteria: Subjects with any cancer diagnosis before cohort entry date. No use of National Health Insurance before the cohort entry date. Low dose aspirin prescription before cohort entry date. Subjects with conditions contra-indicated for low dose aspirin use before cohort entry date.

Ages Eligible for Study
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Minimum Age: 40 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 |
| --- | --- |
| Long-term users<br>Adults using low-dose aspirin for > 3 years | Drug: Aspirin (Acetylsalicylic Acid, BAYE4465)<br>* Low dose of aspirin, i.e. < 150 mg daily<br>|
| Episodic users<br>Adults using low-dose aspirin inconsistently, or consistently but < 3 years | Drug: Aspirin (Acetylsalicylic Acid, BAYE4465)<br>* Low dose of aspirin, i.e. < 150 mg daily<br>|
| Former users<br>Subset of adult Episodic users of aspirin who discontinued the drug for at least 1 year before case/ control date | Drug: Aspirin (Acetylsalicylic Acid, BAYE4465)<br>* Low dose of aspirin, i.e. < 150 mg daily<br>|
| Non-consumers<br>Adults who did not use low-dose aspirin | Other: No drug<br>* Non-consumers<br>* Other names: No aspirin;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of subjects with colorectal cancer | Number of subjects with colorectal cancer for each cohort (long-term, episodic and former users of aspirin, and non-users). | Up to 14 years | 
| Number of subjects with esophageal cancer | Number of subjects with esophageal cancer for each cohort (long-term, episodic and former users of aspirin, and non-users). | Up to 14 years | 
| Number of subjects with gastric cancer | Number of subjects with gastric cancer for each cohort (long-term, episodic and former users of aspirin, and non-users). | Up to 14 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Duration of aspirin use to colorectal cancer | The duration of low-dose aspirin use in years to colorectal cancer. | Up to 14 years | 
| Time from aspirin discontinuation to colorectal cancer | Period of time in years from discontinuation of aspirin use to detection of colorectal cancer. | Up to 14 years | 
| Stage of colorectal cancer | The stage of cancer will be determined according to the International Classification of Diseases for Oncology (ICD-O-3). | Up to 14 years | 
| Number of fatal cases due to colorectal cancer | Derived from Taiwan Mortality database. | Up to 14 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Low-dose aspirin,, Cancer prevention