Table 2 Exclusion criteria

• CKD GFR category 5 by KDIGO classification (eGFR < 15 mL/min/1.73 m²)

• Pre-existing CVD: angina, MI, stroke (ischaemic or haemorrhagic [intracerebral/subarachnoid]), TIA, significant peripheral vascular disease, coronary or peripheral revascularisation for atherosclerotic disease; aortic aneurysm is not an exclusion criterion

• Pre-existing condition associated with increased risk of bleeding other than CKD: upper GI bleed or peptic ulcer in the previous 5 years, lower GI bleed in previous 12 months, active chronic liver disease (such as cirrhosis), bleeding diathesis (investigator opinion)

• Taking over the counter aspirin continuously

• Currently prescribed anticoagulant or antiplatelet agent

• Currently and regularly taking other drugs with a potentially serious interaction with low-dose aspirin, including non-steroidal anti-inflammatories (except topical preparations) and nicorandil

• Known allergy to aspirin or definite previous clinically important adverse reaction to aspirin

• Poorly controlled hypertension (latest recorded systolic blood pressure [BP] ≥180 mmHg and/or diastolic BP ≥105 mmHg)

• Other conditions which in the opinion of the GP would preclude prescription of aspirin in routine clinical practice, for example significant anaemia or thrombocytopenia

• Pregnant or likely to become pregnant during the study period

• Malignancy that is life-threatening or likely to limit prognosis, other life-threatening co-morbidity, or terminal illness

• Behaviour or lifestyle that would render subject less likely to comply with study medication (e.g. alcoholism, substance abuse, debilitating psychiatric conditions or inability to provide informed consent)

• In prison

• Currently participating in another interventional clinical trial or who have taken part in a trial in the last 3 months (Covid-19 vaccine studies are acceptable)