A Comparative Study of Metformin alone, in Combination with Insulin or Metformin Plus Insulin in Presence of Simvastatin in Libyan Diabetic Patients

Type 2 of diabetes mellitus (DM) is associated with progressive failure of pancreatic B-cells to secrete insulin, decreased insulin action, due to reduced insulin receptors at the target sites. Dyslipidemia is a common risk of DM and is responsible to a large extent for cardiovascular disease-related morbidity and mortality. This study was planned to compare the effects of metformin alone and a combination of metformin and insulin in presence of simvastatin on glycemic and lipid levels in Libyan diabeticpatients. This retrospective study was conducted at Benghazi Diabetic Center (Libya) on 100 patients with type 2 DM of 40-60 years old. Patients were selected for follow up on basis of inclusion and exclusion criteria, and were divided into three groups. The first group (n=30), received metformin (1-2 gm/day). The second group (n=40) received metformin (1-2 gm/day) and insulin (mixtard 30/70, 30-60 units/day) and third group (n=30) received metformin (1-2 gm/day), insulin (30-60 units/day) plus simvastatin (40 mg/day). Glucose blood levels (FBG, PPBG and HBA1c), lipid profile (TC, TG, HDL-C, LDL-C and AI), hepatic function (ALT, AST, ALP and Bilirubin) and renal function (creatinine and urea) were measured for each patient. All the patients had a good glycemic control with significant decrease in HbAc1 of metformin plus insulin treated group. No significant differences in lipid profile of metformin treated group and metformin plus insulin treated group were observed. Date revealed both significant increase in HDL-C and decrease in TC, LDL-C and atherogenic index levels but without any change in TG in metformin and insulin treated group as compared with metformin, insulin plus simvastatin treated group. All the findings of hepatic and renal functions were within the normal range except for bilirubin which significantly increased in metformin, insulin plus simvastatin treated group compared with other treated groups.In conclusion, the efficacy of metformin in controlling hyperglycemia was enhanced with insulin without negative effects. Simvastatin was effective in controlling dyslipidemia associated with DM and produced a profound reduction in TC and LDL-C of the patients.