Effect of Metformin Therapy on Serum Fetuin Levels in Insulin Resistant Type 1 Diabetics

Insulin resistance may develop with Type 1 diabetes. Insulin resistance is currently recognized by the estimated glucose disposal rate. Serum fetuin has been accused as a risk factor for metabolic syndrome.

To determine the relationship between the serum fetuin and insulin resistance in Type 1 diabetes subjects and the effect of short-term Metformin therapy on this relationship.

40 T1DM male ≥ 18 years of age were screened for insulin resistance (defined using estimated glucose disposal rate). 20 subjects (Group I) were insulin resistant with a mean estimated glucose disposal rate of (7.15±0.37 mg/kg/min) while 20 subjects (Group II) were non-insulin resistant with a mean estimated glucose disposal rate of (9.08±0.42 mg/kg/min). Fasting blood sugar, 2 hours-post prandial blood sugar, HbA1c%, C-peptide, lipid profile, highly sensitive-C reactive protein, and serum fetuin were assessed. Group I were given 1gm Metformin twice daily for 3 months as an add-on to their insulin regimen. All anthropometric and laboratory parameters were reassessed at the end of the 3 months.

Group I had a higher age, BMI and waist/hip ratio, FBS, PPBS, HbA1c%, TC, LDL-C, TG, Hs-CRP and serum fetuin (ρ ≤ 0.001), and a lower C-peptide (ρ=0.001). Fetuin showed a positive correlation with age, FBS, HbA1c%, and Hs-CRP. After Metformin therapy, FBS, PPB and HbA1c%, Hs- CRP and fetuin decreased (ρ≤0.001) while eGDR and insulin dose in units/kg increased (ρ <0.001). Correlation after Metformin therapy within Group I showed that eGDR was inversely related with FBS and PPBS and fetuin showed a positive correlation with Hs-CRP.

Serum fetuin was elevated in insulin resistant T1DM, yet this was not associated with eGDR. Levels of fetuin-A and HsCRP decreased after Metformin therapy.