Coastal water salinity and hypertension in Bangladesh
- Bangladesh
- In Progress
- October 2023 – October 2027
- Strengthening Primary Healthcare /Multi-Sectoral Interventions / Empowering people & Communities / RCS / Community Engagement Initiatives
Background
Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in Bangladesh, in which hypertension is responsible for more than half of CVD-related deaths. High salinity in drinking water is strongly associated with increased blood pressure, hypertension, kidney damage and CVD risk. Drinking water in coastal areas contain high levels of sodium (200-900 mg/L), leading to an additional intake of more than 2 g/day with drinking water on top of salt consumed through food. Elevated sodium in blood circulation is associated with raised systolic blood pressure. Several technologies, such as Rainwater harvesting, Pond sand filters (PSF), Managed aquifer recharge (MAR), Deep tube wells, and Reverse Osmosis (RO) system have been introduced to ensure fresh drinking water in coastal Bangladesh however most of the initiatives have failed to achieve long-term impact. Poor maintenance, weak governance, limited community engagement, and lack of integration with the health system have undermined the sustainability. Moreover, people living in coastal areas are not aware of the health impact of drinking saline water. In parallel, primary health care services for NCD prevention and management remain under resourced and insufficiently adapted to address climate-sensitive health risks.
NIHR Global Health Research Centre for Non-Communicable Diseases and Environmental Change in Bangladesh, will address these interconnected challenges through a multi-sectoral, system-integrated approach to mitigate drinking water salinity and strengthen NCD services, especially for CVD, diabetes, and chronic kidney disease among vulnerable coastal populations.
Aim
The aim of this study is to strengthen primary health care systems for NCD management while improving access to low-saline drinking water in order to reduce CVD risk among adults living in coastal areas of Bangladesh.
Study Objective
Research Methodology
This study consists of two sequential phases: a formative phase and an intervention phase.
Formative research:
The formative phase adopted a mixed-methods approach and was implemented over 18 months in the coastal sub-districts of Koyra (Khulna) and Assasuni (Satkhira). The work was structured around two interlinked work packages to generate an integrated understanding of drinking water salinity, health system capacity and community needs. The first work package focused on situational analysis, combining evidence review, environmental and water quality assessments, health system readiness assessment, and stakeholder engagement. Quantitative and qualitative data were collected to map water sources, assess drinking water salinity, screen households for CVD risk, and capture perspectives from communities, healthcare providers, policymakers, and implementing partners. This phase identified key contextual, institutional, and system-level factors shaping both exposure to saline drinking water and access to NCD services. The second work package emphasized participatory co-design, bringing together communities, technical experts, and public health practitioners through a series of collaborative workshops. This process informed the development of context-specific drinking water salinity mitigation solutions, a digital platform to strengthen NCD service delivery, and integrated health promotion tools and clinical protocols, with a particular focus on prevention and management of chronic kidney disease.
Intervention phase:
The intervention study will apply a quasi-experimental design using a difference-in-differences approach to evaluate a multicomponent package to be implemented between February 2026 and September 2027. The objective of the of the intervention are-
- To evaluate a multicomponent intervention (primary care strengthening for NCDs through integration of digital health, community mobilization, and improved access to low saline drinking water through a multi-sectoral engagement) is associated with a change in mean systolic blood pressure among adults with moderate-to-high CVD risks; and
- To assess the effectiveness of a multi-sectoral intervention for increasing the proportion of households in accessing low-saline drinking water among the people with low CVD risk.
The intervention will be delivered in 30 villages under 15 Community Clinics in Koyra sub-district which have selected due to high exposure to saline drinking water. Assasuni sub-district will serve as the usual care/comparison area, matched on levels of salinity exposure and key socioeconomic characteristics. Adults aged 40 years and above will be screened using the WHO non-laboratory-based 10-year CVD disease risk assessment tool. Participants with moderate to high CVD risk will receive healthcare through better equipped primary healthcare facilities and improved access to low saline drinking water. The primary care intervention (theme 1) includes digitalized NCD service delivery supported by a clinical decision support system, algorithm-based management of hypertension, diabetes, and chronic kidney disease and health education through engaging government community health workers and mobilizing communities. The multi-sectoral intervention (theme 2) includes improving access to low-salinity drinking water through coordinated, multi-sectoral action with communities and local government. It focuses on improving access to low-saline drinking water, raising awareness of salinity-related health risks, establishing standard operating procedures for the operation and maintenance of water sources, and strengthening systems for registration, monitoring, and supervision of drinking water infrastructure. The participants with low or no CVD risk will receive only multi-sectoral intervention.
The theme 1 intervention will be implemented by the government primary healthcare providers and the community health workers with the support of directorate general of health services (DGHS). Theme 2 intervention will be implemented government community health workers along with community people such as, community leaders (religious leaders), teachers, youth group, women group with the collaboration of local government and department of public health engineering (DPHE).
The research team will collaborate closely with key government partners, including the DGHS and the DPHE to strengthen the capacity of local service providers and ensure that the interventions are integrated into existing government systems. To understand how well the interventions work, data will be collected from both areas where the interventions are implemented and areas where usual services continue. This will help assess the impact, implementation process, and cost-effectiveness of the program.
The overall implementation of the intervention will be guided by three governance bodies: a local-level advisory committee, a Public Advisory Board (PAB), and a national-level steering committee for ensuring accountability, community engagement, and alignment with national priorities.
Expected Impact
Conclusion
By combining water salinity mitigation, digital strengthening of NCD services, and community engagement, the intervention aims to reduce CVD risk while improving sustainable access to low saline drinking water in vulnerable coastal populations. The findings will generate policy-relevant evidence to inform climate-resilient health system strengthening in Bangladesh and other LMICs.
