A new discovery could change how type 1 diabetes is diagnosed and managed in individuals of African descent, researchers say.
In type 1 diabetes, the insulin-producing beta cells in the pancreas stop working in childhood or young adulthood. The disease has always been attributed to an autoimmune process in which the immune system produces so-called autoantibodies that mistakenly attack the pancreas.
But studying 894 volunteers in Cameroon, Uganda and South Africa with youth-onset diabetes, researchers found that 65% of them did not have the usual autoantibodies typically seen in people with type 1 diabetes in other parts of the world. Nor did they have the genes that usually predispose to the disease, or features consistent with other known types of diabetes, such as type 2 and malnutrition-related diabetes.
“This suggests that many young people in this region have a different form of type 1 diabetes altogether and is not autoimmune in origin,” study leader Dana Dabelea of the University of Colorado Anschutz Medical Campus said in a statement.
Comparing the data to studies in the U.S., the researchers found that 15% of Black Americans diagnosed with type 1 diabetes had a form of the disease similar to the patients in Sub-Saharan Africa, characterized by negative autoantibodies and a low genetic risk score, according to a report in The Lancet Diabetes and Endocrinology, opens new tab.
White Americans with T1D, however, showed the typical autoimmune pattern, and even if they didn’t have detectable autoantibodies, their genetics still pointed to autoimmune diabetes.
Clinicians in parts of Africa had long suspected that some children diagnosed with type 1 diabetes did not quite fit the standard profile, the researchers said.
Most studies to date have focused on white Western populations, overlooking regional and genetic diversity in disease presentation, they noted.
“These findings are a wake-up call,” study co-leader Professor Moffat Nyirenda of the London School of Hygiene & Tropical Medicine Uganda Research Unit said in a statement.
“They challenge our assumptions about type 1 diabetes and show that the disease may present differently in African children and adolescents. We urgently need to deepen our investigations into the biological and environmental factors driving this form of diabetes and ensure our diagnostic and treatment approaches are fit for purpose in African settings.”
