Triple Therapy for Type 2 Diabetes

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Triple therapy in type 2 diabetes: insulin glargine or rosiglitazone added to combination therapy of sulfonylurea plus metformin in insulin-naïve patients, by J. Rosenstock and colleagues. Diabetes Care 29:554–559, 2006.

What is the problem and what is known about it so far?

Studies have shown that treating diabetes with just one type of diabetes drug is sometimes not successful over a long period of time. A second or third type of drug is often needed to keep blood glucose at a safe level. Because of concerns over bad effects and extra cost, doctors do not always like to prescribe additional medications.

Why did the researchers do this particular study?

Some patients who take one or two diabetes drugs still have problems controlling their diabetes. The researchers wanted to see if taking an additional diabetes drug can safely help these patients.

Who was studied?

A total of 217 patients with type 2 diabetes who were at least 18 years old and were overweight. The patients were taking sulfonylurea (a drug that increases the amount of insulin released by the body) and metformin (a drug that helps the body use glucose) before the study began to treat their diabetes.

How was the study done?

The patients were put into one of two groups. One group took rosiglitazone (a drug that helps insulin work better and lowers glucose levels) in addition to their sulfonylurea and metformin; the other group took insulin in addition to their sulfonylurea and metformin.

The patients who took insulin took insulin glargine, which is a long-acting insulin.

The study lasted 24 weeks.

What did the researchers find?

Both groups were able to improve their blood glucose after they added low doses of insulin or rosiglitazone to their sulfonylurea and metformin.

Rosiglitazone helped the most for those patients who began the study with very high blood glucose levels. However, insulin also helped lower blood glucose levels and resulted in less weight gain and better cholesterol levels (cholesterol is a waxy fat-like substance that builds up in the blood vessels).

What were the limitations of the study?

This study lasted only 24 weeks, and a longer study may have had different results. Also, this study looked at small doses of insulin and rosiglitazone. Larger doses may have had different effects.

What are the implications of the study?

The study showed that a third type of drug therapy may help patients who have trouble controlling their diabetes. Doctors need to take into account the risks and benefits of each drug, beyond just how it affects diabetes, when starting patients on "triple therapy."

FOR MORE INFORMATION

Other Medications for Type 2 Diabetes

101 Medication Tips for People with Diabetes, 1st Edition

Insulin 70/30 mix plus metformin versus triple oral therapy in the treatment of type 2 diabetes after failure of two oral drugs, by S. Schwartz and colleagues. Diabetes Care 26:2238–2243, 2003