A newly identified genetic condition may be causing significant delays in type 2 diabetes diagnoses and increasing the risk of severe complications for thousands of Black and South Asian men in the UK, with global implications. A study by the University of Exeter, in collaboration with Queen Mary University of London, reveals that a genetic variant known as G6PD deficiency is prevalent in these populations, potentially affecting millions worldwide.
The research, funded by a Wellcome Discovery Award, highlights that approximately one in seven Black men and one in 63 South Asian men in the UK carry the G6PD deficiency. This genetic variant does not directly cause diabetes but interferes with the accuracy of the HbA1c blood test, a standard diagnostic tool for diabetes. As a result, men with this deficiency are diagnosed with type 2 diabetes an average of four years later than those without the variant, posing a serious health risk.
Understanding G6PD Deficiency
G6PD deficiency affects over 400 million people globally, predominantly among those of African, Asian, Middle Eastern, and Mediterranean descent. Despite its prevalence, it often goes undetected due to a lack of symptoms. The World Health Organization recommends routine screening in high-risk populations, but such measures are not widely implemented in the UK or other countries.
Professor Inês Barroso from the University of Exeter emphasized the urgency of revising testing practices to address health disparities. “Our findings highlight the urgent need for changes to testing practices to tackle health inequalities,” she stated. “Doctors and health policy makers need to be aware that the HbA1c test may not be accurate for people with G6PD deficiency and routine G6PD screening could help identify those at risk.”
The Impact on Diabetes Diagnosis
The HbA1c test is the international standard for diagnosing and managing type 2 diabetes, utilized in 136 countries. However, for individuals with G6PD deficiency, this test may underestimate blood sugar levels, leading to delayed diagnoses and increased risk of complications. The study, published in Diabetes Care, indicates that men with G6PD deficiency are at a 37% higher risk of developing diabetes-related microvascular complications, such as damage to the eyes, kidneys, and nerves.
Dr. Veline L’Esperance, a GP and Senior Clinical Research Fellow at QMUL, expressed concern over these findings. “These findings are deeply concerning because they show how a widely used diagnostic tool may be failing communities that are already disproportionately affected by type 2 diabetes,” she said. “We need greater awareness among healthcare professionals and stronger policies to ensure equitable screening and diagnosis.”
Addressing Health Inequities
The study underscores the broader issue of health inequalities faced by Black and South Asian communities in the UK. Professor Faye Ruddock, Chair of the Caribbean and African Health Network, highlighted the barriers these communities face, including stigma, language, and cultural differences, which contribute to delayed diagnoses.
Anna Morris, Assistant Director of Research at Diabetes UK, noted the disparities in diabetes care among different ethnic groups. “Black and South Asian people in the UK are twice as likely to be living with undiagnosed type 2 diabetes than White people,” she stated. “If our most common test to diagnose and monitor type 2 diabetes isn’t accurate for people of all ethnicities, it could seriously compound these problems.”
Future Steps and Global Implications
The research findings are based on genetic and health data from over half a million individuals in the UK Biobank and Genes & Health studies. The multidisciplinary team of researchers linked genetic data to medical information, revealing the significant impact of G6PD deficiency on diabetes diagnosis and complications.
Dr. Esther Mukuka, Director of Research Inclusion at the NIHR, emphasized the importance of addressing these disparities. “At NIHR, we are committed to ensuring research drives fairer healthcare for all,” she said. “Addressing the impact of G6PD deficiency on diabetes testing is an important step towards reducing inequalities.”
The study calls for further research in more diverse populations to confirm these findings globally. As the paper ‘Undiagnosed G6PD deficiency in Black and Asian individuals is prevalent and contributes to health inequalities in type 2 diabetes diagnosis and complications’ suggests, tackling these disparities is essential for improving health outcomes and ensuring equitable healthcare access for all.
