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

The autonomic nervous system controls organs (like the heart and stomach) and the involuntary actions of the body (like breathing and your heart beating). Sometimes this system stops working the way it should when a person is overweight or does not have a healthy heart. Some studies have shown that problems with this system are connected to diabetes in adults who are otherwise healthy.

Why did the researchers do this particular study?

Researchers wanted to figure out the link between diabetes and the autonomic nervous system. They wanted to see whether the function of this system improved when patients changed their lifestyle or took different diabetes drugs. They also wanted to see if a change in nervous system function led to the development of diabetes.

Who was studied?

Adults who were over 25 years of age and had some of the health problems that make a person likely to get diabetes. They were taking part in the Diabetes Prevention Program study.

How was the study done?

The people in the study were put into one of three groups. One group was given advice for leading a healthier lifestyle and was told to take a placebo (a drug that has no effect) twice a day. Another group was given advice for a healthier lifestyle and was given a drug used to treat diabetes. The third group went through a program to change their entire lifestyle.

What did the researchers find?

The researchers found that measurements that showed how well the body organs functioned and how physically fit the participants were (like heart rate) improved in the group that went through the lifestyle change program. The better their organ function and fitness level, the less chance they had of getting diabetes.

What were the limitations of the study?

One limitation of the study is the possibility of measurement errors. This could be fixed by trying other research methods and using the average of several different measurements to make decisions about patients' health.

What are the implications of the study?

The researchers concluded that when people makes changes in their lifestyles that help them become more physically fit and improve the function of the autonomic nervous system, they often will have a lower risk of getting diabetes.

- American Diabetes Association

The association among autonomic nervous system function, incident diabetes, and intervention arm in the Diabetes Prevention Program. Diabetes Care 29:914–919, 2006.