Type 2 diabetes mellitus (T2DM) has reached epidemic proportions worldwide. Its societal effects are magnified in indigenous peoples, who experience significant health disparities, and a high disease burden and complications. Generally, poor access to healthcare and education translates into under-representation of indigenous people in clinical studies. The aim of this sub-analysis was to describe the clinical characteristics of indigenous Hispanic Native American T2DM patients enrolled in a real-life observational study (EDGE), and to evaluate the effectiveness of vildagliptin vs other oral anti-diabetic drugs (OADs) in this population.
EDGE was a prospective, observational study conducted in 45868 patients with T2DM requiring intensification of their existing OAD regimen. Data relating to patient history, metabolic control and treatments were collected. Change in HbA1c, and proportion of patients reaching composite endpoint of HbA1c <7.0% without hypoglycaemia or ≥3% weight gain, were assessed after 12 months of treatment.
Among all enrolled patients, we identified 369 Hispanic Native American patients (0.8% of study population). In the intent-to-treat group, mean age was 56.7 years, BMI 28.4 kg/m2, HbA1c 8.9% and T2DM duration 6.3 years at baseline. After 12 months, vildagliptin-treated patients (n=229) showed a mean HbA1c change of -2.2%, vs -1.3% for patients treated with other OADs (n=37). A higher proportion of vildagliptin-treated patients reached the predefined composite endpoint (46.8% vs 22.9% with other OAD, p=0.008). The likelihood of reaching HbA1c values without tolerability issues was almost three times higher in the vildagliptin-treated patients (unadjusted OR=2.96, 95% CI 1.29, 6.80; p=0.010).
Inclusion of indigenous peoples in real-life clinical studies of new treatment modalities for T2DM remains rare. In this cohort, the add-on vildagliptin treatment was associated with significant HbA1c changes and a higher proportion of patients achieving HbA1c targets without tolerability issues. However, the high baseline HbA1c values also indicate the existence of additional barriers, beyond access to modern treatment, to effective disease management in indigenous peoples with T2DM.