Improving health services to prevent heart attacks and strokes: evidence for interventions (e4i) in large middle-income countries
Largely due to the ageing of their populations and changing lifestyles, middle-income countries (MICs) are facing a rapidly increasing burden of heart attacks and strokes. Most of these cardio- and cerebrovascular disease (CCVD) events are preventable through successful treatment of three major risk factors: diabetes, dyslipidaemia, and hypertension. Yet despite the existence of inexpensive and effective medications, only a small minority of adults with these risk factors in MICs successfully transition through the care continuum from screening to effective treatment. There is currently little to no evidence from these settings on what health services interventions are most effective in reducing the loss of patients along the CCVD risk factor care continuum. Focussing on the four most populous MICs – which jointly account for 43% of the world’s population – E4I thus aims to i) determine at which of the main steps in the care continuum – screening, linkage to care, and retention in care – the greatest loss of patients occurs; ii) establish which health services interventions have been most effective in reducing the loss of patients at each of these three care steps; and iii) ascertain the causal effect of reducing the loss of patients along the care continuum on individuals’ health and economic outcomes. To do so, E4I will use novel causal inference techniques from different academic disciplines on large population-based cross-sectional and cohort datasets with jointly over seven million participants, challenging the frequently-held beliefs in public health that only randomised trials can provide causal effect estimates and that cohort data’s principal value is the study of disease aetiology. By generating urgently needed knowledge on how to more effectively deliver proven treatments for a major public health problem in MICs, E4I will decisively advance public health research and has the potential to have an important impact on population health globally.