This study is conducted in a cohort of low dose aspirin (ASA) users previously ascertained. The aims of the post hoc analyses are:

To estimate the incidence of uncomplicated peptic ulcer (UPU) in a cohort of low-dose ASA for secondary prevention of vascular disease and the relative risk of UPU associated with use and discontinuation of use of low dose ASA.

To estimate the effect of proton pump inhibitors (PPI) on the occurrence of UPU among users of low-dose ASA for secondary prevention of vascular disease To evaluate the effect of other risk factors on the occurrence of UPU among users of low-dose ASA for secondary prevention of vascular disease.

The risk of uncomplicated peptic ulcer in a cohort of secondary prevention aspirin users

Inclusion Criteria:

- Patients aged 50-84 years in 2000-2007 with a first prescription of low dose ASA ( see study population description)

Exclusion Criteria:

- Patients aged below age 50 and 85 years and above ( see study population description)

Patients aged 50-84 yrs who had a first prescription of low-dose ASA (75-300mg/day) for secondary cardiovascular or cerebrovascular prevention in 2000-2007 in The Health Improvement Network database in the UK. Patients had to be enrolled with their PCP (Primary Care Physician) for at least 2 years and have a health contact in the year prior. Patients with use of aspirin ever recorded in the database before start of follow-up as well as patient with cancer or alcohol abuse were excluded. Individuals were followed up until the earliest occurrence of one of the following endpoints; first recorded diagnosis of uncomplicated peptic ulcer, canser, alcohol abuse or alcohol related disease, reaching the age of 85 years old, date of last practice data collection, death or end of follow-up ( 30 September 2011).Patient records were manually reviewed to validate cases.