Diabetes DPG Public Library

The prevalence of type 2 diabetes in Mexico is among the highest in the world and a major public health problem with prevalence in Mexico at 18% in 2022. The statistics of 2022 show approximately twice that reported for non-Hispanic white and European populations.

Family history studies are well documented with estimates of the genetic heritability of type 2 diabetes ranging from 30-70%. Genome wide association studies suggest genes account for roughly 20% of disease susceptibility.

This cross sectional study of 134,548 Mexican adults evaluated the association of Indigenous American ancestry (AMR) percentage with type 2 diabetes while providing clarity about the shape and strength of the associations. The purpose of this study was to evaluate data taken from the Mexico City Prospective Study (MCPS) from April 14, 1998 through September 28, 2004 and examine the association between the percentage of Indigenous American genome ancestry and the prevalence of type 2 diabetes and prediabetes.

AMR ancestry was evaluated across tenths ranging from 34% to 94% with a mean of 66.2%.

After adjustment for age and sex, each 20% increase in AMR was associated with increased odds of type 2 diabetes and prediabetes development. Adjustment for socioeconomic status, lifestyle factors and adiposity brought down the odds however they continued to be significantly higher than the non-native population. Odds rates for type 2 diabetes and prediabetes were higher for women than men and for younger than older individuals.

The findings indicate a direct causal role of AMR ancestry percentage on type 2 diabetes and prediabetes and the Indigenous population in Mexico. There is revealed up to a 20% absolute difference in the estimated prevalence of type 2 diabetes across the full AMR ancestry percentage spectrum reflecting the contrast between non-native populations.

While type 2 diabetes is influenced by numerous genetic, environmental, and socioeconomic factors, the AMR ancestry percentage appears to play an important role on top of these factors. This may help explain why the prevalence of type 2 diabetes in Mexico is higher than expected when viewed from a multifactor perspective including population BMI.