- Metformin reduces insulin resistance and improves aortic and carotid health in youth with type 1 diabetes (T1D), suggesting a potential benefit for preventing cardiovascular (CV) events.
Why this matters
- Evidence of cardiovascular disease (CVD) is already present in T1D, and CVD is the leading cause of mortality in patients with T1D. Insulin resistance (IR) correlates with coronary artery calcium and cardiovascular events in adults.
- Increasing insulin dose may worsen BMI and IR, as IR correlated with hypoglycemia and not hyperglycemia.
- Adjunctive therapies to reduce insulin and IR using metformin warrant consideration.
- Effects of Metformin on Cardiovascular Function in Adolescents with Type 1 Diabetes (EMERALD) study hypothesized that youth with T1D have impaired vascular function and that metformin decreases IR and improves vascular health.
- 49 youth with T1D ages 12-21 years (40% with BMI ≥90% percentile; 44% male) and 24 control patients of similar age participated.
- Treatment was 2000 mg metformin titrated over 4 weeks plus basal insulin or placebo plus basal bolus insulin for 3 months total treatment.
- Compared with the placebo group, children with T1D in the metformin group had improvement at 3 months in glucose infusion rates (12.2±3.2 vs −2.4±3.6 uIU/mL; P<.01 wall shear stress vs n>2; P<.03 and far wall diastolic carotid intima-media thickness vs mm p=".04).<span" class="">
- Metformin also decreased BMI and whole-body IR.
- No severe adverse events were reported.
- Medication adherence was high in both groups (metformin, 94%; placebo, 91%).
- Small sample size.