Feasibility of a community-based intervention for the diagnosis and management of hypertension in two rural populations in Kenya and The Gambia: IMPLEMENT-IHCoR Feasibility Study Protocol

IntroductionHypertension is the leading global risk factor for mortality, causing over 10 million deaths annually. In sub-Saharan Africa, hypertension prevalence is high, particularly in rural areas, where it is less likely to be diagnosed, treated, or controlled effectively. This results in a high burden of complications, including heart failure, stroke, and kidney disease. Community-centred approaches using community health workers (CHWs), risk-based approaches and simplified treatment regimens have shown promise in improving hypertension management. However, there is limited evidence on the effectiveness of such approaches in rural sub-Saharan Africa. This study aims to evaluate the feasibility and acceptability of a community-based intervention to improve hypertension management in rural Kenya and The Gambia. The primary aim of this study is to assess the feasibility of a community-centred intervention for hypertension management in rural Kenya and The Gambia. The objectives are to evaluate the interventions adoption, fidelity, reach, and dose; understand the mechanisms of action and contextual factors affecting its implementation; assess acceptability from the perspectives of patients, healthcare providers, and policymakers; estimate the costs associated with the intervention; and evaluate study procedures to inform the design of a future full-scale trial. Methods and AnalysisWe will conduct a mixed-methods, non-randomised, single-arm feasibility study, designed in accordance with the CONSORT framework and checklist for feasibility and pilot studies, including best practice guidance for non-randomised feasibility studies. The study will be conducted in two rural sites: Kilifi, Kenya, and Kiang West, The Gambia. The intervention was co-designed with stakeholders and includes community-based hypertension screening by CHWs, risk stratification, and hypertension-mediated organ damage (HMOD) assessment at primary healthcare facilities, followed by treatment initiation using single-pill combination (SPC) antihypertensive therapy for eligible individuals. Training will be provided to all healthcare providers involved in the study. We will screen 500 participants aged 30-80 years at their residence (250 from each country) and we expect that about 45% will be referred for additional assessments and of these 25% (or 10% of the total sample) will be prescribed treatment with SPC. Data collection to evaluate the intervention and its implementation will involve quantitative measures of feasibility and clinical outcomes; observations to assess fidelity and costing measures; and qualitative interviews and focus group discussions with patients, healthcare providers, and policymakers to understand the acceptability and contextual influences on intervention implementation. Ethics and disseminationEthics approval was obtained from the Kenyan National Committee for Science, Technology and Innovation (NACOSTI) (ref: 415561), the Gambia Government/Medical Research Council Joint Ethics Committee (ref: 31372) and the London School of Hygiene and Tropical Medicine Ethics Committee (ref: 31372). Study findings will be disseminated through peer-reviewed publications, conferences, policy briefs, community engagement forums, and accessible summaries shared via the Improving Hypertension Control in Rural sub-Saharan Africa (IHCoR-Africa) and partner newsletters. Trial registrationThis study is registered with the ISRCTN- The UKs Clinical Study Registry ( ), and Pan African Clinical Trials Registry (PACTR202504839027548). ARTICLE SUMMARYStrengths and limitations of this study O_LIThis study uses a robust mixed-methods design incorporating both quantitative and qualitative data to evaluate feasibility, acceptability, and implementation of a complex intervention. C_LIO_LIThe intervention was based on extensive formative health systems research, co-designed with stakeholders in two countries, and embedded within existing community and health system structures, enhancing its relevance and potential scalability. C_LIO_LIWe are conducting a comprehensive training and using standardised protocols to ensure consistency in intervention delivery and data collection across study sites. C_LIO_LIAs a single-arm feasibility study without a control group, findings on intervention effectiveness will be limited and primarily focused on informing a future definitive trial. C_LI