A low-cost intervention leads to “clinically meaningful” reductions in blood pressure and better blood pressure control, researchers report.
The intervention includes home visits by community healthcare workers to monitor blood pressure (BP) and provide lifestyle coaching. In the trial, researchers coupled the intervention with physician training and coordination with the public health care infrastructure.
Uncontrolled hypertension, a major risk factor for cardiovascular and kidney diseases, is a leading cause of death globally. In rural parts of low- and middle-income countries, particularly in Asia, where health systems are suboptimal. One in four adults suffers from hypertension—70% of which is uncontrolled—leading to some of the highest death rates from both cardiovascular and kidney diseases.
Getting health care to those who need it
At the end of the study, the decline in mean systolic blood pressure was 5 mmHg greater in the intervention group versus the control group, which received the usual care. Reduction in mean diastolic blood pressure and blood pressure control (<140/90 mmHg) was also better in the intervention group.
The intervention increased adherence to antihypertensive medications and lipid-lowering medicines, and improved some aspects of self-reported health. Additionally, there was an indication of a reduction in deaths from cardiovascular disease in the intervention group.
“A sustained 5 mmHg reduction in systolic BP at a community level historically translates into about a 30% reduction in death and disability from cardiovascular disease,” says Tazeen H. Jafar, a professor from the Health Services and Systems Research Programme at Duke-NUS Medical School who is also a professor of global health at the Duke Global Health Institute.
“Our study demonstrates that an intervention led by community health workers and delivered using the existing healthcare systems in Bangladesh, Pakistan, and Sri Lanka can lead to clinically meaningful reductions in BP as well as confer additional benefits—all at a low cost.
“Community health workers are an integral part of the primary care infrastructure for the successful door-to-door delivery of maternal and child healthcare in South Asia—as well as China, Mexico, and Africa,” Jafar adds. “Our findings show that community health workers can have an equally important role in managing hypertension.”
The multi-country Control of Blood Pressure and Risk Attenuation—Bangladesh, Pakistan, Sri Lanka (COBRA-BPS) study is a cluster randomized trial that evaluated the effectiveness of the multi-component intervention among 2,550 individuals with hypertension living in 30 rural communities in the three South Asian countries over two years.
This is the first multi-country trial of its kind and, as such, serves as a model of South-South collaboration. While there are differences in the health systems and some population characteristics in the countries involved, blood pressure control rates are uniformly poor in all of them. Nonetheless, the study shows similar results in all three countries with the standardized strategies, suggesting that the intervention has validity in different settings.
National advisory committees have been established in the three countries, with representatives from professional societies, public health groups, public agencies, relevant pharmaceutical companies, and non-governmental organizations. Discussions with provincial health departments and the committees are ongoing to facilitate the scaling up of the intervention in the three countries.
The dangers of high blood pressure
“Uncontrolled hypertension is a major cause of cardiovascular disease, especially stroke, in Bangladesh. The COBRA-BPS strategies of community-health-worker-driven home-based monitoring of blood pressure using a digital monitor, promotion of a healthy lifestyle, and referral have created a high demand for much-needed quality hypertension care services in rural Bangladesh,” says coauthor Aliya Naheed of the International Centre for Diarrhoeal Diseases Research, Bangladesh (ICDDR,B), the study’s principal investigator in Bangladesh.
“Uncontrolled hypertension and lack of awareness of the disease are alarmingly high in Pakistan. Controlling BP through lifestyle modification and antihypertensive therapy can be the single most important way to prevent the rising rates of cardiovascular disease and deaths in Pakistan,” says coauthor Imtiaz Jehan from Aga Khan University, Pakistan, the study’s principal investigator in Pakistan.
“This trial provides timely evidence for sustainable, low-cost, and pragmatic solutions for effective BP control that can be integrated into our public primary healthcare system of community health workers and referrals to basic health units through standardized training and task shifting.”
“Despite having access to effective medicines free of charge through State healthcare institutions in Sri Lanka, only about 25% of those treated achieve BP control,” says coauthor H. Asita de Silva from the University of Kelaniya, Sri Lanka, the study’s principal investigator in the country.
“Traditional approaches to health service delivery, reliant on people presenting to clinics, are clearly not good enough. Instead, innovative models of cardiovascular care must incorporate primary healthcare strategies that enhance reach to underserved populations. COBRA-BPS has demonstrated that a community-level intervention delivered by our dedicated community health workers can significantly improve BP control.”
Eric Finkelstein, a health economist at Duke-NUS and DGHI, has started a formal cost-effectiveness analysis. The study group’s early estimates suggest that scaling up the COBRA-BPS intervention nationally in the three countries would cost less than US$11 per patient annually.
“The public health implications of our findings are significant,” Jafar adds. “A low-cost program like ours could be adapted and scaled up in many other settings globally, using the existing healthcare infrastructure to reduce the growing burden of uncontrolled hypertension and potentially save millions of lives, as well as reduce suffering from heart attacks, strokes, heart failure, and kidney disease.”
The research appears in the New England Journal of Medicine.
Funding for the study came from the Joint Global Health Trials scheme, which includes the Medical Research Council, the UK Department for International Development, the National Institute for Health Research, and the Wellcome Trust. Data management and statistical analysis support came from the Singapore Clinical Research Institute (SCRI).