Integrated Primary Care Strategies to Reduce High Blood Pressure- A Cluster Randomized Trial in Rural Pakistan and Sri Lanka

Cardiovascular disease (CVD) has become the leading cause of mortality worldwide, accounting for 30% of deaths even in low- and middle- income countries (LMICs). In South Asia, high rates of CVD are observed at a younger age than in other countries, causing a greater loss of productive life years with severe economic consequences. High blood pressure (BP) confers the greatest attributable risk to death and disease associated with CVD.

Our Wellcome Trust funded Control of Blood Pressure and Risk Attenuation (COBRA) trial (2004 to 2007) in Karachi, Pakistan, suggested the combined strategy of family based home health education (HHE) delivered by trained community health workers (CHW) plus care of patients by trained private general practitioners (GP) to optimally manage hypertension had the most marked beneficial impact on BP compared to usual care, or single interventions. However, the COBRA intervention was designed for an urban South Asian setting, where private GPs cater to over 75% of the patients seeking care. Therefore, the trial did not use the public health infrastructure per se, nor did it evaluate whether mid-level providers (MLP) can deliver first steps of hypertension care including prescribing first and second line anti-hypertensive medications.

Most of South Asia is still rural (64% Pakistan, 85% Sri Lanka) where prevalence of hypertension is high and healthcare infrastructure and provider characteristics are very different compared to the urban setting. About 40-50% patients in rural Pakistan and Sri Lanka seek care (including prescription medications) from MLPs (visiting nurse, dispenser, assistant medical officer) at the government community clinics. Thus whether hypertension management by this cadre of MLPs is effective, especially when rolled out using government healthcare infrastructure is not known. Our proposed study is designed to answer this question in rural Pakistan and Sri Lanka.

We propose a cluster RCT in 30 rural communities in Pakistan and Sri Lanka including 2500 individuals with hypertension with 2 year follow-up to evaluate the effectiveness of "triple approach" of combining intervention by 1) HHE plus 2) trained government primary health center MLP plus 3) trained private practitioners or "dual approach" of combining intervention of 1 and 2 only compared to no intervention (or usual care) on lowering blood pressure, and to determine whether these approaches are incrementally cost-effective.

The delivery of care by the various public providers and the private sector is now recommended by the World Health Organization in several communicable disease control programs, such as Directly Observed Treatment (DOTS) for tuberculosis and management of malaria. However, evidence on the effectiveness of using the same platform for chronic non-communicable disease management is rather scarce.

Moreover, wider discussion among the relevant stakeholders in South Asia to refine and implement the proposed activities would be beneficial, and would increase the likelihood of up-scaling the cost-effective strategies which could also be extended to other chronic diseases (and even infectious diseases) in an integrated manner that is potentially sustainable and applicable in rural settings across many Asian countries with similar ethnic populations and healthcare infrastructure. Comparing and contrasting the experiences from Sri Lanka and Pakistan should also provide valuable lessons not only for these two countries but also for other countries in the region and beyond.

Design: Cluster, randomised, RCT in rural Pakistan (15 clusters) and Sri Lanka (15 clusters).

Ten of the 30 clusters each will be randomised to the following three groups:
1) "Triple Approach" of: 1) home health education (HHE) by trained community workers plus 2) trained government primary health center mid level providers (MLP) plus 3) trained private practitioners;
2) "Dual Approach" of: 1 plus 2; as above
3) "Usual care" or no intervention

Target population: 2500 adults aged 40 years or older with hypertension (systolic BP >=140 or diastolic BP>= 90 mm Hg or on anti-hypertensive medications)

Interventions:

1. Home health education (HHE) by trained community health workers (CHWs): The government CHW will be trained in conveying standardized lifestyle messages for better control of blood pressure using behavior change communication strategies.

2. Trained government primary health center MLP: The MLPs (lady health visitors, assistant medical officers) in the government primary care clinics will be trained over 3 days in initial management of the first steps of hypertension according to a standard algorithm.

3. Trained private practitioners: All private practitioners (registered mid-levels and physicians) practicing allopathic medicine in the private sector will be given training similar to that of the government MLPs.

Follow-up: All subjects will be followed-up for 2 years at their home by independent outcomes assessors.

Primary outcome: change in systolic BP.

Primary Cost-Effectiveness measure: Incremental cost per mm Hg reduction in systolic BP and projected CVD disability adjusted life year (DALY) averted.

Sample size: A total of 2500 hypertensive adults in 30 cluster, alpha of 0.05, ICC of 0.02, will provide >99% for 7 mm Hg difference between the triple approach and usual care, and >80% power for 4 and 3 mm Hg difference between dual approach vs usual care, and triple vs dual approach, respectively

The proposed trial is expected to have a sustained impact on the following:

1. Address major public health challenge in South Asia: Our research question is of high public health priority for South Asia. Non-communicable diseases (NCD) including cardiovascular diseases (CVD) are responsible for 2/3rd of all deaths globally. Hypertension is the leading attributable risk factor for CVD. National data indicate at least 1 in 4 adults suffers from hypertension in Pakistan. The estimates are equally high in Sri Lanka. However, there are no specified public health programs at the federal, provincial or district level with the expertise in designing and managing programs for prevention and control of hypertension. Thus, opportunities for screening and managing hypertension are missed, and catastrophic expenditures from complications including heart attack, stroke, and heart failure are perpetuating the cycle of poverty.
Our trial aims to evaluate potentially effective and sustainable strategies through the primary care system for treating hypertension in rural Pakistan and Sri Lanka. If successful, scaling up the interventions would be immensely beneficial to the South Asian region and possibly other low-and middle- income countries in terms of reduced mortality and human resources.

2. Health Systems Strengthening and Capacity Building for Hypertension (and NCD) care:Strengthening health systems for delivery of services for hypertension care would be achieved through the development of integrated models of reducing high blood pressure within the existing public health infrastructure of rural South Asian countries currently focused on delivery of communicable diseases care. The integrated delivery of hypertension care will leverage the current financing mechanisms of chronic infectious diseases like malaria & tuberculosis and introduce and build NCD programmes in the disadvantaged regions of the world with a significant double burden.

3. Capacity strengthening for hypertension (and NCD) research in rural South Asia: will be achieved through South-South and North-South collaboration. Our previous experience in urban Pakistan with COBRA, and the well-functioning public sector infrastructure in Sri Lanka are unique strengths of the trial, and would promote intellectual exchange, and learning from shared experiences.

4. Detailed Policy Relevant Economic Evaluation: We plan to conduct detailed cost effectiveness analyses from the societal, government and participants perspectives for rural Pakistan and Sri Lanka. The analysis from the societal perspective would be performed for Pakistan and Sri Lanka together to provide estimates with implications for other South Asian countries and other LMICs. Country specific estimates will also be computed for local applicability. This information is very valuable for the stakeholders and is likely to enhance uptake of findings as sustainable national/provincial public health programs.

5. Knowledge Translation and Policy Impact: The trial will provide an opportunity to establish country- and region-specific institutional mechanisms to translate NCD research into policy & programmes. The trial evaluates delivery of hypertension management strategies using the public health infrastructure. If successful, this will serve as a platform for up-scaling other model programs into public health interventions. Moreover, the engagement of government with investigators would bring hypertension management agenda into national and regional health focus and also facilitate implementation of NCD control programmes in other LMICs. We will further catalyse the process of research to policy translation in Asia Pacific region and supporting organizations and government contacts, and by involving the key stakeholders from national governments and medical research councils, NGOS and international agencies.