Modified insulin most effective for controlling post-meal blood sugar levels

Pre-mixed insulin analogues, a modified form of conventional pre-mixed human insulin, are more effective than long-acting analogues for controlling high blood sugar levels after meals in patients with type 2 diabetes, according to a report funded by the Agency for Healthcare Research and Quality, part of the US Department of Health and Human Services.

Conventional pre-mixed human insulin, however, appears to be equally effective as pre-mixed insulin analogues for lowering blood sugar levels when patients go eight or more hours without eating, according to the report. A version of the analysis is available online in the Annals of Internal Medicine.

Type 2 diabetes accounts for more than 90 percent of diabetes. The number of Americans diagnosed with type 2 diabetes tripled from 5.6 million in 1980 to 15.8 million in 2005. Obesity increases the risks of developing type 2 diabetes. Diabetes can cause serious problems with the heart, kidneys, eyes and nerves. Many patients with type 2 diabetes control their blood sugar through diet and use of oral medications. Recent research suggests that good blood glucose control can reduce loss of sight, kidney failure, and heart disease.

The new report was compiled by the Johns Hopkins University Evidence-based Practice Center in Baltimore, one of 14 such centres that are funded by AHRQ through its Effective Health Care program. The report represents a systematic review of 45 research studies and is intended to provide unbiased, evidence-based information so that patients, clinicians and others can make the best possible treatment decisions.

"While it is clear that pre-mixed insulin analogues offer certain advantages to patients with diabetes, what is good for one patient may not be good for another," said AHRQ Director Carolyn M Clancy, MD. "This report offers an important reminder that patients with diabetes should review their treatment plans carefully with their physician."

Pre-mixed insulin analogues are a modified form of conventional pre-mixed human insulin. AHRQ’s report compared pre-mixed insulin analogues with conventional pre-mixed human insulin, oral diabetes drugs, and two other kinds of insulin analogues – long-acting (or "basal") analogues, and rapid-acting (or "bolus") analogues.

Although non-insulin oral medications are used as a first-line treatment for patients with type 2 diabetes, insulin is frequently required at some stage during the course of the disease. Under such circumstances, some patients are controlled with long-acting insulin alone while others need a combination of long-acting and rapid-acting insulins to control blood sugar levels after meals, especially meals with high sugar content.

About 28 percent use some form of insulin to control blood sugar levels and limit complication risks from type 2 diabetes. Pre-mixed insulin analogues, approved in the US in 2003, are produced by genetically modifying selected proteins of human insulin. Insulin analogues were developed as an alternative to conventional pre-mixed human insulin to provide tighter control of blood sugar levels.

(Source: Annals of Internal Medicine: Agency for Healthcare Research and Quality: September 2008)