Estimating the population impact of screening strategies for identifying and treating people at high risk of cardiovascular disease: modelling study

Objective To estimate the potential population impact of different screening strategies for identifying and treating people at high risk of cardiovascular disease, including strategies using routine data for cardiovascular risk stratification, in light of the UK government's recommended national strategy to screen all adults aged 40-74 for cardiovascular risk. Design Modelling study using data from a prospective cohort, EPIC-Norfolk (European Prospective Investigation of Cancer-Norfolk). Setting An English county. Participants 16 970 men and women aged 40-74 and free from cardiovascular disease and diabetes at baseline. Main outcome measures The main outcomes were the population attributable fraction, the number needed to screen to prevent one new case of cardiovascular disease, the number needed to treat to prevent one new case of cardiovascular disease, and the number of new cardiovascular events that could be prevented. Relative risk reductions for estimated treatment effects were derived from meta-analyses of clinical trials or guidelines from the National Institute for Health and Clinical Excellence. Results 1362 cardiovascular events occurred over 183 586 person years of follow-up. Compared with the recommended government strategy, a stepwise screening approach using a simple risk score incorporating routine data could prevent a similar number (lower to upper estimates) of new cardiovascular events annually in the United Kingdom (26 789, 20 778 to 36 239) and 25 134 (19 450 to 34 134), respectively) but requiring only 60% of the population to be invited to attend a vascular risk assessment. A similar number of cardiovascular events (25 016, 19 563 to 33 372) could also be prevented by inviting everyone aged 50-74 for a vascular assessment. Using a participant completed Finnish diabetes risk score questionnaire or anthropometric cut-off points for risk prestratification was less effective. Conclusions Compared with the UK government's recommended national strategy to screen all adults aged 40-74 for cardiovascular risk, an approach using routine data for cardiovascular risk stratification before inviting people at high risk for a vascular risk assessment may be similarly effective at preventing new cases of cardiovascular disease, with potential cost savings.