Type 2 diabetes mellitus in sub-Saharan Africa: challenges and opportunities

• Published in: Nature reviews. Endocrinology 2022-04, Vol.18 (4), p.219-229
• Main Authors: Motala, Ayesha A., Mbanya, Jean Claude, Ramaiya, Kaushik, Pirie, Fraser J., Ekoru, Kenneth
• Format: Article
• Language: English
• Subjects: 692/163/2743/137/773; 692/699; Africa South of the Sahara - epidemiology; Diabetes; Diabetes mellitus (non-insulin dependent); Diabetes Mellitus, Type 2 - epidemiology; Diabetes Mellitus, Type 2 - etiology; Endocrinology; Epidemiology; Humans; Medicine; Medicine & Public Health; Noncommunicable Diseases - epidemiology; Prevalence; Review Article; Rural populations; Urban areas; Urbanization
• ISSN: 1759-5029; 1759-5037
• DOI: 10.1038/s41574-021-00613-y

Type 2 diabetes mellitus (T2DM), which was once thought to be rare in sub-Saharan Africa (SSA), is now well established in this region. The SSA region is undergoing a rapid but variable epidemiological transition fuelled by the pace of urbanization, with disease burden profiles shifting from communicable diseases to non-communicable diseases (NCDs). Information on the epidemiology of T2DM has increased, but wide variations in study methods, diagnostic biomarkers and criteria hamper analytical comparison, and data from high-quality studies are limited. The prevalence of T2DM is still low in some rural populations but moderate or high rates are reported in many countries/regions, with evidence for an increase in some. In addition, the proportion of undiagnosed T2DM is still high. The prevalence of T2DM is highest in African people living in urban areas, and the gradient between African people living in urban areas and people in the African diaspora is rapidly fading. However, data from longitudinal studies are lacking and there is limited information on chronic complications and the genetics of T2DM. The large unmet needs for T2DM care call for greater investment of resources into health systems to manage NCDs in SSA. Proposed health-system paradigms are being developed in some countries/regions. However, national NCD programmes need to be adequately funded and coordinated to stem the tide of T2DM and its complications. This Review outlines the burden of type 2 diabetes mellitus and its complications in sub-Saharan Africa, including the pathogenesis, standards of care for treatment and preventive strategies. Key points Previously considered rare, type 2 diabetes mellitus (T2DM) is now firmly established in sub-Saharan Africa (SSA). Although prevalence is low in some rural populations, moderate or high rates are reported in many countries/regions, with evidence for an increase in prevalence in some areas. Information on the burden of T2DM has increased, but there is a need for high-quality epidemiology studies using harmonized approaches for sampling, data collection and diagnostic methods. The increase in T2DM in SSA is associated with modifiable risk factors, such as urbanization and obesity, and there is a high proportion of undiagnosed T2DM. Data on the genetics of T2DM are emerging and suggests a greater degree of genetic diversity in T2DM susceptibility in African people compared with other populations. There are large unmet needs for T2DM care and nati