Intervening on hypertension in Zambia: development of a culturally sensitized lifestyle programme to reduce disease incidence in urban areas

Background/purpose: Hypertension, like other non-communicable diseases, is becoming a major public health problem for Sub-Saharan Africa (SSA). Its increasing prevalence is driven by an epidemiological transition with more people leading unhealthy lifestyles, including poor diet and physical inactivity. This project aimed to explore the use of participatory methods with an urban community in Zambia in co-developing a culturally sensitized hypertension prevention intervention. Methods: The intervention development study was divided into four phases. I scoped and synthesized existing literature on risk factors (non-modifiable and modifiable) for hypertension in SSA in Phase One. The identified risk factors and their drivers informed Phase Two community members focus group discussions and stakeholder interviews to explore the local context in the study site to clarify the problem, identify which hypertension risk factors were malleable (potential factors to target), the mechanism of change, and how to deliver this. The findings informed the development of the causal pathway, the intervention theory of change and the Phase Three co-development of the intervention core components and small-scale evaluation. Five co-development workshops (four with local residents and one with local stakeholders) iteratively informed identification of priority risk factors, the delivery format and setting, and finalization of intervention core components. The pilot intervention was then tested with volunteer participants (N=34) to assess feasibility, acceptability and potential effectiveness in Phase four. Results: The scoping review identified the most common risk factors for hypertension in SSA. Residents FGDs and key stakeholder interviews, informed by the scoping review findings, identified a number of potentially malleable hypertension risk factors at individual and interpersonal levels, including high salt intake and other dietary factors, low physical activity, excess body weight, central obesity, high alcohol intake and smoking. From these, the workshops prioritised intervening on salt intake, other dietary factors, and physical inactivity. Using these suggestions, an 8-week group-based intervention (CHiPI) was codeveloped. Stakeholders proposed evaluation of the CHiPI on a small scale and delivery through churches: “nearly all residents belong to a church”. Stakeholders also identified community health workers and church leaders as delivery facilitators. The intervention core components were agreed and refined in close consultation with residents. These included linguistic and cultural adaptations of SMART goal setting and self-monitoring tools, which were iteratively tested and refined to reflect the local socio-cultural context. The small-scale evaluation of the intervention showed high acceptability, feasibility and potential effectiveness in improving health literacy, adoption of healthier diets (less salt added during cooking [p=0.014], reduction in added salt to the plate at mealtimes [p=0.001], increased fruit intake [p=0.001], reduced fried meals [p = 0.001]), increased physical activity [p=0.01] and reduced sedentary lifestyle [p = 0.001]. Reductions in body weight [p = 0.002], BMI [p = 0.001], WC [p = 0.001], SBP [-3mmHg, p=0.003] and DBP [-4mmHg, p = 0.001] were also observed. Conclusions and implications: Participatory methods succeeded in engaging local residents and stakeholders in the development of a potentially effective culturally sensitized, 8-week, group-based hypertension prevention lifestyle intervention for delivery through churches in Zambia. Having demonstrated high feasibility, acceptability and potential effectiveness, taking this intervention to a larger evaluation to obtain evidence of effectiveness can inform hypertension prevention intervention development in Zambia and other SSA countries