Study: Metformin Improves Cardiovascular Outcomes in Type 1 Diabetes Patients

Results recently published from a clinical trial found a common medication for type 2 diabetes patients may decrease the risk of cardiovascular disease (CVD) in patients with type 1 diabetes. 

For the MERIT study, 23 type 1 diabetes patients without CVD received metformin for eight weeks (treatment group, TG) and were matched with type 1 diabetes patients receiving standard treatment (standard group, SG; n = 9) and controls (control group, CG; n = 23).


At baseline, TG had significantly higher levels of plasma miR-222, miR-195, and miR-21a than the healthy controls (P = 0.009, P < 0.0001, and P = 0.0001, respectively). SG had significantly higher baseline levels of plasma miR-195 and miR-21a than CG (= 0.0012 and P = 0.02, respectively), but miR-222 baseline levels did not greatly differ between the groups. TG and SG plasma miR-222 and miR-21a levels were similar at baseline, but plasma miR-195 levels was much higher in TG than SG at baseline (P = 0.03). 

After eight weeks, TG had significantly reduced levels of plasma miR-222 (P = 0.007), miR-195 (= 0.002), and miR-21a (= 0.0012), while miRs remained unchanged in SG. 

“Anti-angiogenic miRs are increased in T1DM,” the study authors wrote. “Metformin has cardioprotective effects through downregulating miR-222, miR-195 and miR-21a, beyond improving glycemic control.” 

The results were published in the International Journal of Molecular Sciences. 

Lead study author Dr. Jolanta Weaver said of the findings, “This is an exciting development as understanding this underlying mechanism opens up the possibility of new forms of treatment which will lower the chances of patients with type 1 diabetes developing heart disease.” 

Dr. Weaver, a senior lecturer in diabetes medicine at Newcastle University and honorary consultant diabetologist at Queen Elizabeth Hospital, Gateshead, added, “These results confirm that as well as improving a patient’s blood sugar control, metformin is working to protect the heart.” 

Review of Metformin Use for Type 2 Diabetes Prevention 

Metformin Use and Gastric Cancer Risk in Diabetic Patients After Helicobacter pylori Eradication 

Gastric Banding and Metformin Have Similar Effects on β-cell Function in Some Type 2 Diabetes Patients 

Metformin and AMP Kinase Activation Increase Expression of the Sterol Transporters ABCG5/8 (ATP-Binding Cassette Transporter G5/G8) With Potential Antiatherogenic Consequences 

Sources: Newcastle University International Journal of Molecular Sciences