Cardiovascular disease risk reduction in sub–Saharan Africa (CARisSA)

Background Sub-Saharan Africa (sSA) bears a disproportionate burden of premature mortality from cardiovascular disease (CVD). Evidence suggests that a community-centred approach targeting individuals with high overall CVD risk may be effective in addressing barriers to care and reducing CVD events. Aims and objectives We aim to co-design and evaluate a community-centred, contextualised, multi-component, intervention to improve management of individuals with high overall CVD risk in sSA. Our objectives are to: Co-design a community-centred intervention for reducing overall CVD risk Evaluate the feasibility of this intervention Evaluate the effectiveness of this intervention and conduct an economic evaluation Conduct a process evaluation Methods The study will take place in Kilifi, Kenya and Kiang West, The Gambia. First, we will co-design the intervention using a participatory approach in three workshops including 30 participants (individuals living with CVD risk factors, caregivers, advocacy group members, healthcare workers, and decision-makers). Proposed components include task-sharing, digital technologies to support clinical management, combination therapy, and peer support. Second, we will conduct a 6-month feasibility trial of the co-designed intervention. We will include four clusters (two intervention and two control) and 100 participants. We will use a mixed-methods approach including quantitative trial data and qualitative interviews with trial participants and healthcare workers. Third, we will conduct an open-label parallel cluster randomised superiority trial comparing the intervention with standard care for adults at high overall CVD risk. The co-primary outcomes will be systolic blood pressure and low-density lipoprotein concentration at 12-months. We will randomise 44 clusters (40 eligible participants per cluster) for a total sample of 1760 participants. This will provide a power of 90% at a two-sided significance level of 0.05 to detect a meaningful difference in the co-primary outcomes. We will assess the cost-effectiveness and budget impact of the intervention versus standard care. Finally, we will conduct a process evaluation to explore for whom, how, and why our intervention had (or did not have) an impact on trial outcomes. We will use a mixed-methods approach informed by the RE-AIM/PRISM framework and Normalization Process Theory. We will use trial data, in-depth interviews, and focus group discussions. Timeline In year 1 we will co-design the intervention, in year 2 we will evaluate its feasibility, during years 3 to 5 we will conduct the cluster trial, with the corresponding economic and process evaluations. Anticipated impact and dissemination This will be the first study to generate evidence of the effectiveness of a community-centred multi-component intervention for overall CVD risk in sSA. Our research will provide crucial information about how such an intervention can be successfully implemented, scaled-up, and sustained. We will take advantage of our ongoing community and policy-maker engagement to ensure our findings have an impact on health services in the study settings. We will disseminate our findings more broadly through our global network of collaborators, including researchers and international policy organisations. Our training and capacity-strengthening activities will provide valuable career opportunities for 400 researchers from sSA.