The investigators designed this prospective, randomized control study to compare the efficacy and safety between the basal insulin glargine therapy and metformin-based OADs after correction of the glucose toxicity with a short period of intensive insulin therapy.

Detailed Description:

OBJECTIVE-Type 2 diabetes is associated with defects in insulin secretion and insulin sensitivity. Hyperglycemia may aggravate these defects, a feature known as glucose toxicity. Previous studies have shown that acute correction of hyperglycemia in subjects with long-standing type 2 diabetes gives only short-term improvement in glycemic control after discontinuation of insulin. The current study attempts to identify whether basal insulin glargine or metformin-based OADs for further management would have a long-term benefit in newly diagnosed type 2 diabetes after short-term intensive insulin therapy.

RESEARCH DESIGN AND METHODS-Newly diagnosed type 2 diabetic patients (fasting blood glucose >200 mg/dL or random blood glucose >300 mg/dL) will be hospitalized and treated with intensive insulin injection for 10 to 14 days. HbA1c were measured before intensive insulin injection. After discharge, patients will be randomized to receive basal insulin injection or metformin-based OADs for further management. Patients will be followed in our clinics and adjust their medication according to their blood glucose levels. HbA1c were measured 6 months later.After the six-month intervention, these patients were continually followed up for another six months. Subjects received an oral glucose tolerance test (OGTT) after the intensive insulin therapy and at the end of the 6th and 12th month.

EXPECTED RESULTS-We will expect that basal insulin glargine,compared with metformin-based OAD treatment,could more effectively maintain adequate glycemic control in newly diagnosed type 2 diabetes after short-term intensive insulin therapy.

Inclusion Criteria:

1. Newly diagnosed type 2 diabetic patients.
2. Drug naïve, with severe hyperglycemia (fasting plasma glucose>11.1mmol/L or random plasma glucose >16.7mmol/L)
3. Those who age between 30 and 70 years old and can inject insulin by themselves.

Exclusion Criteria:

1. Established type 1 diabetes or positive anti-glutamic acid decarboxylase antibody;
2. Malignancy, pregnancy or lactating;
3. History of ketoacidosis;
4. Hepatic dysfunction with alanine aminotransferase 2.5 times higher than the upper limit of normal; serum creatinine >2 mg/dl;
5. Poor blood pressure control (SBP>180mmHg or DBP >110mmHg);
6. Definite coronary artery disease, heart failure, left ventricular hypertrophy;
7. Severe anemia; acute or severe chronic diabetes complications;
8. BMI<18 kg/m2 or ≥41kg/m2;
9. History of alcohol abuse or drug abuse;
10. Mental disorder and other endocrine disorders; dysfunction of digestion and absorption;
11. Chronic diseases need long-term glucocorticoid treatment.