Metformin is an unexpensive and safe drug for treating type 2 diabetes (T2D) that may also have benefits for overweight (OW) patients with type 1 diabetes (T1D) .

Objective: To investigate differences between OW adults with T1D that used metformin + insulin vs. those that used only insulin.

Methods: This was an observational study evaluating adults (≥18 years old) with body mass index (BMI) ≥ 25kg/m2. BRAZDIAB was a retrospective, observational study with T1D patients conducted in Brazilian cities. Clinical data were compared between patients who used metformin as adjuvant therapy (group 1 - G1) vs. those who did not use it (group 2- G2) . Mann-Whitney, Chi Square and linear regression tests were used for statistical analysis.

Results: 6patients were included and 130 (21.5%) used metformin (mean dose: 1258 mg/day) for a mean period of 39.68 ± 38.78 months. Both groups had similar age, T1D duration and insulin U/kg/day (p=0.73; 0.649 and 0.5, respectively) . G1 exhibited higher HbA1c, total cholesterol, triglycerides, BMI and diastolic blood pressure (p=0.03, 0.08, <0.01, <0.and 0,018, respectively) than G2. Metformin use predominated in females (p=0.03) , those with relatives with T2D (p=0.019) , hypertension (p=0.06) and acanthosis nigricans (p=0.047) . G1 had higher frequency of previous infarction (3.17% vs. 0.47%;p=0.03) than G2. A multivariate analysis confirmed an independent association between metformin use and HbA1c (9.17±1.9 vs. 8.64±1.72%; p=0.001) as well as BMI (29.8±3.8 vs. 28,1±3.0kg/m2; p=0.001) .

Conclusions: Metformin use was associated to higher BMI, clinical characteristics of T2D and worse glycemic control, but the differences could reflect the cause of prescription rather than the consequences.


M.Rodacki: None. L.Zajdenverg: None. J.R.Dantas: None. M.E.N.Ramos: None. C.Negrato: None. M.B.Gomes: n/a.



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