Hypertension and diabetes in Africa: design and implementation of a large population-based study of burden and risk factors in rural and urban Malawi

Abstract

BackgroundThe emerging burden of cardiovascular disease and diabetes in sub-Saharan Africa threatens the gains made in health by the major international effort to combat infectious diseases. There are few data on distribution of risk factors and outcomes in the region to inform an effective public health response. A comprehensive research programme is being developed aimed at accurately documenting the burden and drivers of NCDs in urban and rural Malawi; to design and test intervention strategies. The programme includes population surveys of all people aged 18 years and above, linking individuals with newly diagnosed hypertension and diabetes to healthcare and supporting clinical services. The successes, challenges and lessons learnt from the programme to date are discussed.ResultsOver 20,000 adults have been recruited in rural Karonga and urban Lilongwe. The urban population is significantly younger and wealthier than the rural population. Employed urban individuals, particularly males, give particular recruitment challenges; male participation rates were 80.3 % in the rural population and 43.6 % in urban, whilst female rates were 93.6 and 75.6 %, respectively. The study is generating high quality data on hypertension, diabetes, lipid abnormalities and risk factors.ConclusionsIt is feasible to develop large scale studies that can reliably inform the public health approach to diabetes, cardiovascular disease and other NCDs in Sub-Saharan Africa. It is essential for studies to capture both rural and urban populations to address disparities in risk factors, including age structure. Innovative approaches are needed to address the specific challenge of recruiting employed urban males.

Prevalence and risk factors for anemia severity and type in Malawian men and women: urban and rural differences

“…Finally, the large number of missing HIV and anemia observations may have introduced bias in to the sampling. The response rates in urban men were poor, which might introduce selection bias as employed men were challenging to recruit [27]. To minimize missing HIV data, we assessed HIV status from different sources – testing from current or prior study and self-report.…”

“…One site was rural – Chilumba, in southern Karonga district, northern Malawi. The rural study was nested within a demographic surveillance site (DSS) established by MEIRU’s forerunner, the Karonga Prevention Study, in 2002 [25–27]. The other site was an enumerated urban population, in Area 25 within Lilongwe city in central Malawi [25, 27].…”

“…Data collection procedures have been previously described [27]. Sociodemographic information were obtained electronic questionnaires and checks were put in place to identify duplicates.…”

“…Laboratory external quality assurance procedures were carried out by Thistles EQA. For internal control, samples were exchanged between study sites and tests repeated to ensure consistency [27]. HIV status was assessed using Determine and Bioline rapid test kits using serial protocols (conducted at the time of the survey, or in the rural DSS in recent linked studies), or was self-reported for those who were aware of their positive status.…”

Private Intergenerational Transfers, Family Structure, and Health in a sub‐Saharan African Context

“…Our study population in Malawi faces a heavy disease burden, characterized by high levels of child and adult mortality, high prevalence of tuberculosis, malaria, and HIV/AIDS, and a growing burden of non‐communicable diseases (Crampin et al. ; Msyamboza, Mvula, and Kathyola ; Msyamboza et al. ).…”