For people of European ancestry, the risk of developing type 2 diabetes (T2D) increases as the number of first-degree relatives with the condition increases, according to results published in Diabetes & Metabolism.
Despite the high race-specific prevalence of diabetes in patients of African descent, the effect did not extend to this population.
The study included nondiabetic healthy siblings (n=1405) of patients with early-onset coronary artery disease (18-59 years). Participants were followed for incident T2D for a mean of 14 years.
Of the total participants, 861 were of European ancestry and 544 were of African ancestry. T2D occurred in 12.3% of participants with European ancestry compared with 19.1% of participants with African ancestry.
For participants with European ancestry who developed T2D, 32.6% had ≥1 first-degree relative with T2D compared with 53.1% for participants with African ancestry (P <.0001).
The researchers found that any family history of T2D was associated with incident T2D for European ancestry (hazard ratio [HR], 2.53), but not for African ancestry (HR, 1.01). For participants of European ancestry, the risk for T2D increased with the number of afflicted relatives, with HRs of 1.82, 4.83, and 8.46 for 1, 2, and ≥3 affected relatives, respectively. For participants of African ancestry, only ≥3 affected relatives increased the risk (HR, 2.45).
Kral BG, Becker DM, Yanek LR, et al. The relationship of family history and risk of type 2 diabetes differs by ancestry [published online June 5, 2018]. Diabetes Metab. doi: 10.1016/j.diabet.2018.05.004