In a Diabetes Special Issue of The Lancet, researchers have shown that patients with newly diagnosed type 2 diabetes who receive early intensive insulin therapy may be able to improve the function of their insulin-producing β-cells. The therapy regimen has also been associated with the recovering and restoration of blood glucose control.
Type 2 diabetes – commonly known as adult-onset diabetes – is a metabolic disorder characterized by insulin resistance. Several earlier studies have proposed that intensive insulin therapy has the ability to change or slow down the natural progression of the disease, and Professor Jianping Weng (Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China) and colleagues sought to add clarity to these claims.
The researchers conducted a randomized controlled trial at nine centers in China, consisting of 382 patients between the ages of 25 and 70 with type 2 diabetes. There were three groups in the randomization process: 121 patients received the standard oral diabetic drugs, 137 patients received an intensive insulin therapy called continuous subcutaneous insulin infusion (CSII), and 124 patients received the intensive insulin therapy of multiple daily insulin injections (MDI). After regular blood glucose control (normoglycemia) was restored for a period of two weeks, patients stopped receiving treatment and were then followed up on just diet and exercise. Before therapy, after therapy withdrawal, and at 1-year follow-up, researchers performed intravenous glucose tolerance tests and measured blood glucose, insulin, and proinsulin.
The findings of Weng and colleagues support the early intensive insulin therapy. More patients achieved target blood glucose control and achieved it more quickly in both of the insulin groups compared to the group on oral drugs. Of patients in the CSII group, 97% achieved normoglycemia within four days; 95% of patients in MDI group were considered normoglycemic within 5.6 days. Of patients in the oral drug group, only 83.5% were normoglycemic within 9.3 days. Maintenance of blood sugar control (remission rates) were higher after one year in both insulin groups compared to the oral drug group – 51% CSII, 45% MDI, 27% oral drug. In addition, patients in the insulin groups significantly improved the function of β-cells (pancreatic cells that produce insulin).
“Early intensive insulin therapy in patients with newly diagnosed type 2 diabetes has favourable outcomes on recovery and maintenance of β-cell function and prolonged glycaemic remission compared with treatment with oral hypoglycaemic agents,” conclude the authors.
Dr Ravi Retnakaran and Dr Daniel J Drucker (Division of Endocrinology, University of Toronto, Canada) write in an accompanying editorial that, “Although the relevant biological mechanisms and target tissues contributing to preferential improvement in β-cell function remain unclear, these data suggest that use of intensive insulin therapy early in the course of type 2 diabetes warrants further clinical investigation.”
Effect of intensive insulin therapy on β-cell function and glycaemic control in patients with newly diagnosed type 2 diabetes: a multicentre randomised parallel-group trial
J Weng et al.
The Lancet (2008). 371: pp. 1753 – 1760.
Written by: Peter M Crosta