- Pre-diabetes is a significant risk factor for the development of type 2 diabetes, as well as macrovascular and microvascular complication. - Previous studies show that 50% or more loss in islet B-cell function even in Pre-diabetes phase. The early insulin therapy in pre-diabetes may be a strategy in preventing metabolic disorders and cardiovascular disease. - The objective of this study is to find if an initial insulin glargine intervention in pre-diabetes (IGT and /or IFG) could be a strategy in preventing type 2 Diabetes. - Pre-diabetes subjects will receive a insulin glargine therapy with a dosage adjusted to get FBG ≤ 5.3mmol / L as the goal. Insulin glargine treatment will be maintained for three months thereafter to find if it can prevent diabetes.