Adults with type 2 (search) diabetes only use about three-fourths of the prescribed insulin doses recommended by their doctors, according to new research.

The study showed that a large group of older adults prescribed insulin injections (search) to control their type 2 diabetes averaged using only about 77 percent of their prescribed dose.

Researchers say that finding suggests a good intention to follow the prescribed insulin regimen, but it was not enough to keep their disease adequately controlled. The study also showed that the average blood sugar level among the insulin users was higher than recommended.

Although in many people with type 2 diabetes the initial treatment is an oral medication, daily insulin injections may eventually be prescribed for about a third of older men with the condition in order to achieve adequate blood sugar control (search). The number of daily injections may range from one to four or more, which may need to be timed in relation to meals.

Improper Use Leads to Inadequate Control

Researchers say the daily insulin injection burden or fear of injections can make it difficult for many users to manage their insulin prescription. But they say it’s unclear what sort of impact improper use of insulin injections has on blood sugar control.

To answer that question, researchers analyzed insulin use and blood sugar levels among a group of more than 6,000 men who were treated at 12 Veterans Administration medical centers in the U.S. The rate of insulin use during a two-year period was calculated using pharmacy data, and the patients’ average blood sugar levels were tracked during this period.

The study showed that insulin injection use averaged about 77 percent of prescribed amounts among the men. Average three month blood sugar levels as measured by HbA1C (search) were 7.98 percent, which is above the 7 percent threshold recommended by the Veterans Administration guidelines and above the level recommended by the American Diabetes Association.

Researchers say those findings are in line with previous studies that showed most patients prescribed oral diabetes medications took about three-fourths of their drugs as prescribed.

They say these adherence rates reflect good overall diabetes self-management, but the resulting average elevated blood sugar levels suggest that the rate of insulin use, the prescribed insulin dose, or both were inadequate to achieve good disease control in this group of adults with type 2 diabetes.

By Jennifer Warner, reviewed by Brunilda Nazario, MD

SOURCE: Cramer, J. Diabetes Care, January 2005; vol 28: pp 78-83.