Initial Presentation of Type 2 Diabetes in Adolescents Predicts Durability of Successful Treatment with Metformin Monotherapy: Insights from the Pediatric Diabetes Consortium T2D Registry.

BACKGROUND/AIMS: Many adolescents with type 2 diabetes (T2D) have rapid deterioration of glycemic control on metformin monotherapy within 2 years of diagnosis.

METHODS

Enrollment data from the Pediatric Diabetes Consortium T2D Registry were used to categorize 276 youth with a T2D duration ≥2 years into two groups: (1) participants with HbA1c <7.5% on metformin monotherapy (group 1, n = 75) and (2) participants treated with insulin ± metformin (group 2, n = 201). The characteristics of the groups were compared.

RESULTS

At enrollment, groups 1 and 2 did not differ in age (16.2 vs. 16.8 years) or BMI percentile (99 vs. 98%); group 2 had higher HbA1c (9.9% [85 mmol/mol] vs. 5.9% [41 mmol/mol], p < 0.001). Lower HbA1c and metformin monotherapy at diagnosis were associated with a greater likelihood of adequate control with metformin alone (p < 0.001). In multivariable analysis, HbA1c at diagnosis (p = 0.001) and diabetes duration (p = 0.009) were associated with adequate control on metformin. The HbA1c trajectory after diagnosis was worse in group 2.

CONCLUSION

Durable metabolic control of T2D with metformin monotherapy is most likely in youth presenting with lower HbA1c and with shorter diabetes duration, independent of age, race-ethnicity, and BMI. Elevated HbA1c levels in those on insulin therapy highlight the importance of early diagnosis and a better understanding of glycemic control barriers.