Before oral agents fail: the case for starting insulin early.

The progressive nature of Type 2 diabetes presents a challenge over the choice and course of treatment. Strict metabolic control is recommended to reduce the risk of diabetic morbidity and premature mortality. Treatment usually occurs in a step-wise manner as the insulin secretory capacity of the beta-cells diminishes. There are a variety of oral hypoglycaemic agents (OHAs) to choose from but the efficacy of all is influenced by beta-cell function. Eventual progression to insulin therapy is inevitable after beta-cell failure and it is important that this is not delayed. Insulin in combination with OHAs can significantly improve glycaemic control and provide a 'bridge' from oral-only to insulin-only therapy. Combination therapy requires few injections and there is a reduced tendency for weight gain compared with multiple insulin injection regimens. After starting insulin, metabolic control may significantly improve in OHA-treated patients. It is therefore prudent to initiate insulin at an early stage in the course of Type 2 diabetes. In this context, the use of premixed insulin analogues in combination with OHAs allows effective postprandial glucose control, a twice-daily injection regimen and a short meal-injection interval.