Quantifying risk factor associations for the Primary Prevention of Stroke in different population subgroups

Stroke is a major global cause of morbidity and mortality. It is the fourth leading cause of death in the UK and a leading cause of adult disability, doubling the chances of dementia. With an ageing population, it is expected that by 2035, the absolute numbers of stroke events as well as the number of stroke survivors living with a disability in the UK will rise by a third. It is also well known that certain ethnic minorities bear a disproportionately larger burden of stroke. Thus, preventing stroke is of immense public health importance and expected to bring substantial savings for health and social care expenditures.
Stroke as an outcome is strongly linked to cardiovascular health. Risk factors of stroke include the established biological, lifestyle and psychosocial determinants of, as well as wider socio-economic influences on, cardiovascular disease. Primary prevention of stroke by risk factor modification has been added as an extra domain in the latest European Stroke Action Plan - but further quantification of these risk relationships is recommended. Additionally, primordial prevention or preventing adverse levels of risk factors to begin with has been shown to be a powerful strategy for promoting and maintaining brain health. To this end, the American Heart Association has developed a collection of 7 metrics - Life's Simple 7 (LS7) to track cardiovascular health. These include smoking, BMI, physical activity, diet patterns, total cholesterol, blood pressure and fasting glucose; categorized into poor, intermediate and ideal levels based on selected cut-offs; for both adults and children. They are easily monitored, measurable and modifiable. The metrics are further combined to give an overall cardiovascular health score categorized as inadequate, average and optimal. However, data is lacking on their usefulness and suitability- individually and as a composite measure- in predicting a (fatal/nonfatal) stroke event in a multi ethnic British population. This would be especially useful since current EU scoring systems for e.g. SCORE, use cardiovascular disease mortality as an endpoint and are based on a limited number of modifiable risk factors (blood pressure, cholesterol and smoking). Others such as QRISK do not take into
account diet and physical activity. As such, a widely applicable (first time) stroke risk tool that takes into account multiple risk factors doesn't presently exist.