Type 2 diabetes is a long-term condition that affects how the body uses sugar, also called glucose. When a person has this condition, their body either does not make enough insulin or cannot use insulin properly.
Insulin is a hormone that helps move sugar from the blood into the body’s cells, where it is used for energy. If blood sugar levels stay too high for a long time, it can lead to serious health problems such as heart disease, kidney damage, and nerve issues.
Because of this, keeping blood sugar levels within a healthy range is very important.
For many people with type 2 diabetes, doctors first prescribe a medicine called metformin. This drug helps lower blood sugar by improving how the body responds to insulin and by reducing the amount of sugar made by the liver.
However, over time, metformin alone is often not enough to keep blood sugar under control. When this happens, doctors add another medication. But there are several choices, and it has not always been clear which one works best.
To answer this question, researchers carried out a large study known as the GRADE Study. The goal was to compare four commonly used diabetes medications and see how well they worked when added to metformin.
The study included 5,047 adults with type 2 diabetes from different racial and ethnic backgrounds, making the results more useful for a wide range of people.
All participants were already taking metformin at the start of the study. The researchers then divided them into four groups. Each group received one additional medication. These medications were sitagliptin, liraglutide, glimepiride, and insulin glargine U-100.
Each of these drugs helps control blood sugar in a different way. Some increase the body’s own insulin production, while insulin glargine provides a steady supply of insulin throughout the day.
The study lasted for about four years. During this time, the researchers closely monitored how well each treatment helped people keep their blood sugar within the recommended range. This range is important because staying within it reduces the risk of long-term complications.
The results showed clear differences between the medications. People who took liraglutide or insulin glargine along with metformin were able to keep their blood sugar under control for the longest time.
On average, their blood sugar stayed within the target range for about six months longer than those who took sitagliptin, which was the least effective option in the study. Glimepiride worked a little better than sitagliptin but still did not perform as well as liraglutide or insulin glargine.
One important finding was that these results were similar for all groups of people. Age, sex, race, and ethnicity did not seem to change how well the medications worked. This means the findings can likely apply to many different patients with type 2 diabetes.
However, the study also showed how difficult it can be to manage diabetes over time. Even with these treatments, nearly 75 percent of participants were not able to keep their blood sugar within the target range for the entire four years. This highlights that current treatments, while helpful, are still not perfect solutions.
The researchers also looked at heart health, which is very important for people with diabetes. Heart disease is one of the most common and serious complications of this condition.
Among the four medications, liraglutide stood out because people taking it were less likely to develop heart problems during the study. This added benefit makes it an especially interesting option for doctors and patients to consider.
Although liraglutide and insulin glargine performed the best overall, the study did not find a single treatment that was clearly better in every way. Each medication has its own strengths and limitations. This means that doctors still need to choose treatments based on each person’s needs, preferences, and medical history.
The findings from this large study provide helpful guidance for both doctors and patients. They offer clearer information about which medications may work best when metformin alone is not enough. At the same time, the results show that more research is needed to find better ways to manage type 2 diabetes over the long term.
The study was published in The New England Journal of Medicine and was led by Dr. Henry Burch and his research team. Staying informed about new research like this can help people with diabetes make better decisions about their care and improve their long-term health.
If you care about diabetes, please read studies about Vitamin D and type 2 diabetes, and what you need to know about avocado and type 2 diabetes.
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