BackgroundThis study aims to further clarify whether there are cardiovascular and cerebrovascular bene ts associated with insulin treatment combined with metformin in individuals with type 1 diabetes.
MethodsElectronic databases were searched for randomized controlled trials in which the e cacy and safety of metformin were compared with those of a placebo for the treatment of cardiovascular and cerebrovascular disease among type 1 diabetes patients, and a meta-analysis was conducted.
ResultsThirteen cardiovascular studies were identi ed. In the metformin group, mean carotid intimal media thickness was signi cantly reduced by 0.03 mm, ascending aortic pulse wave velocity by 6.3 m/s, descending aortic wall shear stress by 1.77 dyn/cm 2 , insulin daily dose by 0.05 U/kg/d, body weight by 2.27 kg, fat-free mass by 1.32 kg, body mass index by 0.58 kg/m 2 , hip circumference by 0.29 m, and low-density lipoprotein by 0.16 mmol/L. In the metformin group, ow-mediated dilation was increased by 1.29%, glucose infusion rate/insulin by 18.22 µIU/µL, and waist-to-hip ratio by 0.02. The metformin group showed no differences in blood pressure, reactive hyperemia index, waist circumference, triglyceride, total cholesterol, high-density lipoprotein cholesterol, or body mass index Z score. For cerebrovascular studies were identi ed. But none of them had a risk factor assessment.
ConclusionsThere is strong evidence supporting wider use of metformin to improve cardiovascular and cerebrovascular disease risk among individuals with type 1 diabetes, not just obese or adults.