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.

INTRODUCTION

Hypertension 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.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 intervention's 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 ANALYSIS: We will conduct a mixed-methods, non-randomised, single-arm feasibility study, designed in accordance with the Consolidated Standards of Reporting Trials (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 codesigned with stakeholders and includes community-based hypertension screening by CHWs, risk stratification and hypertension-mediated organ damage 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 DISSEMINATION: Ethics approval was obtained from the Kenyan National Committee for Science, Technology and Innovation (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 and partner newsletters.

TRIAL REGISTRATION NUMBER: This study is registered with the ISRCTN- The UK's Clinical Study Registry (ISRCTN81228019), and Pan African Clinical Trials Registry (PACTR202504839027548).