"Sleep is modifiable," said Kristen Knutson, research associate (assistant professor) in the department of health studies at the University of Chicago and first author of the paper. "We’ve known for some time that skimping on sleep can impair glucose tolerance even for healthy people. Now we have evidence connecting chronic partial sleep deprivation and reduced blood-sugar control in patients with diabetes."
"Although we can’t be certain whether sleep loss makes diabetes worse or the diabetes interferes with sleep, it only makes sense for everyone, but especially patients with diabetes, to give themselves the opportunity to get enough sleep," Knutson said.
The study focused on 161 African-American patients being treated at the University of Chicago The researchers found that, on average, the 161 diabetes patients got very little sleep and had poor glucose control. Mean sleep duration was six hours a night. Only six percent reported getting eight hours of sleep on weeknights and only 22 percent reported getting at least seven hours. Seventy-one percent had poor sleep quality. The median HbA1c score was 8.3 percent.
Many patients with diabetes have painful complications that can interfere with sleep. Even after the researchers excluded 39 patients who reported such pain, however, two out of three of the remaining 122 patients reported poor quality sleep. The average HbA1c among those patients was almost as high: 8.2 percent.
Insufficient or poor quality sleep was closely associated with higher HbA1c results. For patients with no complications of their diabetes, a three-hour “perceived sleep debt”—the difference between how much sleep they felt they needed and how much they think they got—was associated with a 1.1 percentage-point increase in HbA1c levels, for example from 7.5 percent up to 8.6 percent.
For patients with at least one complication of diabetes—such as nerve pain, kidney damage or coronary artery disease—decreased sleep quality appeared to be more important. An increase of five points (out of 21) on the PSQI was associated with a 1.9 percentage-point increase in HbA1c, for example from 8.7 percent up to 10.6 percent.
MEDICA.de; Source: University of Chicago Hospitals