Drugs: Insulin (Novolin 30R) monotherapy or combined with one or two oral drugs (metformin 0.5 mg tid and pioglitazone hydrochloride 15 mg qd).

• Insulin (Novolin 30R) was titrated according to the level of blood glucose until reached euglycemia (FPG≤6.1mmol/L and/or P2hBG≤8.0mmol/L and/or HbA1c ≤6.5%). After glucose was well controlled within these targets for 4 weeks, insulin dosage was gradually decreased until discontinued;
• Pioglitazone hydrochloride was discontinued if the glucose was well controlled at the 6th week after the cessation of insulin;
• Metformin was the last drug that to be discontinued if the glucose was still well controlled at the 4th week after the cessation of pioglitazone.

hyperglycemia below diagnostic thresholds for diabetes without active pharmacologic therapy or ongoing procedures of 5 years' duration.

hyperglycemia below diagnostic thresholds for diabetes without active pharmacologic therapy or ongoing procedures of more than 3 months' duration, and less than 5 years.