Early Insulin Use in Type 2 Diabetes

What are the cons?

It is generally recognized that type 2 diabetes is one of the major challenges of the 21st century. Its prevalence is growing rapidly worldwide, particularly in developing countries (1). It remains the first cause of blindness, end-stage renal disease, and nontraumatic lower-limb amputation and one of the major causes of cardiovascular disease (2,3). Because of its high morbidity and excess mortality, it has become a tremendous burden on health care cost (4).

In the last decade, a number of interventions have been shown to be effective in the prevention of diabetes in high-risk populations with impaired glucose tolerance and/or impaired fasting glucose (5–7). Yet, few countries have adopted policies for the screening and strategies for treating subjects with pre-diabetes. Furthermore, despite the development of newer therapies for treatment of diabetes, the disease is still associated with a high incidence of microangiopathy and macrovascular complications. Any new strategies that could help to curtail the burden of diabetes would be greatly appreciated.

More recently, it was postulated that early insulin replacement in type 2 diabetes, and perhaps even in pre-diabetes, may reduce cardiovascular risk and may even offer protection for the β-cell (8,9). However, a closer look at the available data does not support the hypothesis. The Outcome Reduction with an Initial Glargine Intervention (ORIGIN) study is still ongoing and therefore does not allow any conclusion in pre-diabetes. In type 2 diabetes, however, the published data support neither a beneficial effect of insulin therapy per se on microvascular complications, nor on cardiovascular events and mortality. In addition, the data suggesting that insulin therapy can improve the β-cell response to a glucose challenge could just as well be interpreted as being due to the improvement in glycemic control, rather than to the insulin therapy. And finally, …