Lay summary
This study aims to improve how we predict someone’s risk of cardiovascular disease by testing a new blood test that more accurately measures a person’s lifetime exposure to smoking. Current tools often rely on self-reported smoking history, which can be inaccurate. Our test uses DNA methylation, a type of chemical change in the blood linked to smoking, to provide a more reliable measure. Early results suggest it may predict disease risk better than current methods. We will analyse blood samples from a large group of people to see if this test can improve risk prediction, particularly across all ethnic groups in Aotearoa New Zealand. If successful, this test could lead to more accurate and equitable cardiovascular disease risk assessment, making healthcare more effective and cost-efficient.