Ethnic disparities in glycaemic biomarkers among multi-ethnic populations: A narrative review of evidence from Sub-Saharan Africa and global contexts.

Samukelisiwe Zwane; Nokukhanya Thembane

doi:10.51168/yzyzjt41

Autori

Samukelisiwe Zwane Faculty of Applied and Health Sciences Department of Biomedical Sciences Mangosuthu University of Technology
Nokukhanya Thembane Department of Biomedical Sciences, Faculty of Applied and Health Sciences, Mangosuthu University of Technology, South Africa

DOI:

https://doi.org/10.51168/yzyzjt41

Rezumat

Accurate diagnosis and monitoring of diabetes mellitus rely on biomarkers such as glycated haemoglobin (HbA1c) and fasting plasma glucose (FPG), yet the reliability of these biomarkers may vary across ethnic populations due to genetic, haematological, and lifestyle factors. Despite growing evidence of ethnic disparities, no comprehensive synthesis has focused on Durban's multi-ethnic population within the broader Sub-Saharan African and global context.

This narrative review synthesises evidence from over 50 studies examining ethnic variations in HbA1c and FPG levels, the concordance between these biomarkers, and the contributing genetic, lifestyle, and healthcare factors, with particular emphasis on Durban, Sub-Saharan Africa, and global comparative populations.

The review reveals consistent evidence that Indian/South Asian populations exhibit poorer glycaemic control compared to African and White counterparts. HbA1c frequently overestimates glycaemia in non-White populations, leading to discordance with FPG-based diagnoses. Genetic diversity, dietary patterns, healthcare access, and urbanisation interact to shape these disparities. The pathogenesis of type 2 diabetes in Black Africans appears to diverge from European-derived models, underscoring the need for population-specific research. Quality assessment of the reviewed literature revealed considerable heterogeneity, with 36% of studies rated high quality, 44% medium quality, and 24% low quality, with common limitations including lack of OGTT confirmation, absence of haematological correction, self-reported lifestyle data, and predominance of cross-sectional designs.

Population-specific diagnostic thresholds, contextually tailored interventions, and improved healthcare access are urgently needed to address ethnic inequities in diabetes care. Future research should prioritise comparative studies within multi-ethnic urban settings, longitudinal designs, and investigation of genetic-epigenetic-lifestyle interactions to inform equitable, evidence-based diabetes prevention and management strategies.

Biografii autori

Samukelisiwe Zwane, Faculty of Applied and Health Sciences Department of Biomedical Sciences Mangosuthu University of Technology

is a BHSc: Medical Laboratory Science researcher with interests in diabetes, metabolic health, and health disparities, with a focus on understanding glycaemic biomarkers and their implications across diverse populations.https://orcid.org/0009-0008-9039-2293
Nokukhanya Thembane, Department of Biomedical Sciences, Faculty of Applied and Health Sciences, Mangosuthu University of Technology, South Africa

is a researcher and a senior lecturer in the Department of Biomedical Sciences at Mangosuthu University of Technology. https://orcid.org/0000-0001-9146-3809

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