Scientists have found that people with diabetes who sleep poorly have higher insulin resistance, and a harder time controlling the disease.

The result suggests that poor sleep may contribute to worse outcomes in people with diabetes.

"Poor sleep quality in people with diabetes was associated with worse control of their blood glucose levels," said Kristen Knutson, assistant professor of medicine and lead author of the study.

"People who have a hard time controlling their blood glucose levels have a greater risk of complications. They have a reduced quality of life. And, they have a reduced life expectancy," said Knutson.

For the study, the researchers monitored the sleep of 40 people with diabetes for six nights.

The subjects wore activity monitors on their wrists at night, which measure their wrist movements throughout the night.

Poor sleep, or insomnia, was determined by both poor sleep quality based on the activity monitors and the subject telling the researchers that they often had a hard time falling asleep or woke up during the night.

Among the diabetics, poor sleepers had 23% higher blood glucose levels in the morning, and 48% higher blood insulin levels.

Using these numbers to estimate a person's insulin resistance, the researchers found that poor sleepers with diabetes had 82% higher insulin resistance than normal sleepers with diabetes.

The findings were published in the June issue of Diabetes Care.